Socorro High School

Science Project Requirements Manual

Tommy Carranza Louis M. Foix

Angelica G. Villalobos

Table of Contents Pages I. Purpose/Objectives …………………………………………………… 1 II. Letter to Parents …………………………………………………… 2 III. Project Deadlines …………………………………………………… 3 IV. How to Pick a Science Project …………………………………… 4 V. Steps in the Scientific Method …………………………………… 5 VI. Controls and Variables …………………………………………… 6 VII. Format for a Lab Report (Research Plan) …………………………… 7 VIII. Log Book (Journal) Requirements …………………………………… 8 IX. Sample Log Book …………………………………………………… 9 X. Locating Sources for Your Project …………………………………… 10 XI. Documenting the Sources for Your Project …………………………… 11 XII. Writing Note Cards …………………………………………………… 12 XIII. Parts of the Science Project Paper …………………………………… 13 XIV. The Appearance of Your Scientific Paper …………………………… 15 Parts of the Science Project Paper Covered in Detail in the Order that They Will Appear in the Paper (Bold Print): XV. Title Page …………………………………………………………… 16 XVI. Table of Contents …………………………………………………… 17 XVII. Abstract …………………………………………………………… 18 XVIII. Introduction …………………………………………………………… 19 IXX. Use of Note Cards to Write the Introduction …………………………… 20 XX. Adding Quotes to Your Introduction (Citations) …………………… 22 XXI. Editing Your Introduction …………………………………………… 23 XXII. Materials and Method …………………………………………… 24 XXIII. Materials and Method Sample …………………………………… 25 XXIV. Results …………………………………………………………… 26 XXV. Discussion …………………………………………………………… 27 XXVI. Conclusion …………………………………………………………… 28 XXVII. Glossary …………………………………………………………… 29 XXVIII. Appendix …………………………………………………………… 30 XXIX. Works Cited Page (Bibliography) …………………………………… 31 XXX. Items Required for Backboard …………………………………… 34 XXXI. Backboard Requirements …………………………………………… 35 XXXII. Enhancing Your Science Project Paper …………………………… 37 XXXIII Presenting to the Judges …………………………………………… 38 XXXIV. Sample Science Fair Score Sheet ………………………………….... 39

Acknowledgements

We thank the following people for their contributions in creating this manual.

Oscar Troncoso Socorro Independent School District Printing Department

Purpose

The ultimate purpose of the independent research project is to develop a better, more skilled science student that has learned basic research and problem solving skills. This manual is to assist the student with various parts of the project--beginning with the selection of the research topic and ending with its development into a formal presentation.

Objectives

In order to learn these basic skills, students will be expected to perform library and internet research, perform a controlled experiment and collect data, present their findings in written form, and develop a formal presentation.

How to Pick a Science Project One of the most crucial steps in performing an independent research project is that of picking a topic that is interesting, challenging, at an appropriate level, and has plenty of information to aid in its development. Choose something that you are interested in and something you want to learn more about. It will be necessary for you to speak to different people, such as teachers, librarians, and professionals in your area of interest. Also, make good use of the library and internet. For your convenience, a few internet addresses are listed below to give you a start.

www.sciencedaily.com

www.usc.edu/CSSF/History/1998/By_Category.html www.sciencegems.com/

www.umi.com/proquest(password required; see librarian) http://www.ipl.org/youth/projectguide/

www.parkmaitland.org/sciencefair/index.html http://nesen.unl.edu/teacher/

dogpile.com google.com

http://share3.esd205.wednet.edu/mcillend/SSP.html http://www.usc.edu/CSSF/Resources/Getting Started.html

http://www.scifair.com/2002winners.html http:www.scienceproject.com/

http://www.sciserv.org/isef/students/rules/src.asp

STEPS IN THE SCIENTIFIC METHOD

“A common misperception of science is that it defines ‘truth’. Science is not truth, but rather it is a way of thought. It is a process by which experimentations is used to answer questions. This process of experimentation is called the scientific method and involves several steps.” (Carpi, Anthony. Learning Tower Homepage. The Leaning Tower of Pisa, 1998-1999.) Scientific Method: scientific problem solving done in a systematic manner. Step 1: State the Problem (Know the question your are trying to answer/solve.) Step 2: Gather Information on the Problem (Know some background on the problem; research.) Step 3: Make a Hypothesis (Make an educated guess about the question’s answer. It is a good idea to make this a general statement. For example: If a penny is flipped twenty times, then heads will fall most often.) Step 4: Experiment (Test your hypothesis; try it out. Note: You will be asked to have a minimum of 10 trials for your testing. This will give you a significant number of trials to work with when working with the results.) Step 5: Collect/Record and Analyze Data (Write down the observations. This should be done on a chart of some sort. Use graphs to visually represent your data. It will be imperative that you have these on your research paper as well as your science presentation board. Study it to make sense of it. Note: The Results are the written explanation of your Data; these are not the same as the Conclusion!) Step 6: Conclusion. Using some elaboration A. Restate the hypothesis B. Finding support hypothesis C. Explain what results mean, interpret findings D. Final summary of project E. Suggestions for improving project F. Main Conclusion Steps 7: Repeat Your Work

Controls and Variables

It is important that the student learn how to perform a proper experiment--one in which there is a control. This is called a controlled experiment. In order to have a controlled experiment, the student needs to assign variables. However, there can be different types of variables, such as those listed below. Variables: 1) Constants (Controlled Variables): Items which remain the same (unchanged) throughout the experiment; factor(s) that do not vary in an experiment. 2) Independent (Manipulated) Variable: Item being tested; the item which varies; the only item which is different in an experiment; that item in an experiment which affects the outcome; the factor adjusted by the experimenter. 3) Dependent (Responding) Variable: Factor whose value depends upon the value of the independent variable; results. Set-Up: 1) Control: Part of the experiment used as a standard for comparison. It is predictable. 2) Experimental: Part of the experiment containing the item tested. Not predictable.

Structure of a Controlled Experiment

Control Set-Up Experimental Set-Up Does not have the item tested. Otherwise, everything is the same as the experimental set-up. It is predictable. Example: 10 plants without fertilizer.

Does have the item tested. Otherwise, everything is the same as the control set-up. It is not predictable. Example: 50 plants with differing amounts of fertilizer.

Format for a Lab Report (Research Plan)

A lab report communicates to others what you have done. Therefore, it should be detailed enough for someone to follow and repeat your experiment. Never assume that someone knows what you are speaking about if you do not write it down. NOTE: 1. A research plan and a lab report are very similar. When you are in the process of planning your experiment, you will be asked to write a research plan. On the other hand, you will be asked to write a lab report after you have done an experiment. While both follow the same basic pattern at the beginning, they have some differences after the variables. a. A research plan will not include a table for your observations. Nor will it contain a conclusion. Remember, this is done before you experiment. The research plan below reflects what you will be required to turn in for the S.H.S. Science Fair, S.I.S.D. Science Fair, and Sun Country Regional Science Fair. Once you do one for the school fair, you will not need to do another one for the other fairs, so save your plan. b. A lab report will have observations, and it will have a conclusion. This is done after you experiment. Problem: The question you need to answer. Hypothesis: Your educated guess. Materials: Equipment/tools you need to use. Procedures: Steps/directions you need to follow. These should be numbered and in sequence. 1. 2. (etc...) List: Variables: (See Variables section for more details.) 1) Constants (Controlled Variables): 2) Independent (Manipulated) Variable: 3) Dependent (Responding) Variable: Set-Ups: 1) Control: 2) Experimental: Sources: (Bibliography) At least 5 sources needed for district and/or regional science fair. Only 1 internet source and no encyclopedias Examples of sources: proquest, scientific journals, etc.

Log Book (Journal) Requirements

It is imperative that you document all measurements and observations in a separate notebook referred to as log book or journal. Record information on a daily basis and consider the following things that are required: * Make sure that your data is measured using S.I. Units (metrics). * Write all your observations down. Be detailed. Keep lots of notes because it is better to have too much information than not enough. * Always include the dates and times of your observations. * Keep track of the material used, their quantities and cost. * Do take pictures to be included in your display and research paper. Use the following format:

Date: Time: Measurements: Observations:

Note: Your guardian’s signature is required on the front of your journal. You will not receive credit unless it is signed.

Locating Sources The topic you choose for your science paper should interest you. Therefore, you should know some information about the topic. You are the first source of information. Begin by listing the information that you already know about the topic. This will help you decide what you need to focus your research on and show you how much you really know. Once you have a list of the key ideas that you need to research, you may begin. We’ve listed a few of the places where you can find information. Library No other place contains books, magazines, special catalogs, encyclopedias, science-related reference books, and manuals. Make sure to check the non-fiction area, the periodicals area, and the reference area. Make sure that the materials you are using are not outdated. Always look at the copyright date. Internet The internet is useful, fast, and there’s more information than you probably need. Beware of internet sources because they are not always reliable. Always check the source of the article that you’re reading on the internet. Is the writer/organization well-known and reliable? Is the information supported by research, statistics, etc.? Personal Interviews There are many people who can be considered experts. Your job is to find the right person. Consider speaking to science teachers at school or at the university. Find people whose career is related to your topic or people whose hobby is related to your topic. When conducting an interview, make sure to have your questions pre-checked by a teacher, a tutor, etc. Consider taking a recorder to the interview. Dress and act professionally during the interview and don’t forget to send a thank-you card. Brochures and Pamphlets Many companies produce informational brochures that may be of help to you. For example, if your project is related to water, contact the El Paso Water Utilities education division. It may take time to receive the information from them, so don’t procrastinate. Television, Radio, and Printed News Keep your eyes and ears open for programs or articles that relate to your topic. Write notes as you listen to the program or read the news and remember to write all the source information.

Documenting Your Sources Terms to Know: Document – (v.) to write down all the important information about a topic. Source – (n.) any book, document, article, etc. that you are using in your research Cite – (v.) to write down the bibliographic information of your source Summary – (n.) information that is read and re-written in your own words. Quote – (n) information that is copied directly (word for word) out of a source When you are researching information for your science project and your science paper, you will find lots of information. Some sources will be more useful than others. You will be required to write the important information that you find in your sources on notecards. Your notecards may contain two types of notes:

Summary Information Quoted Information

Summary Information Note Cards The front of your note card must contain the topic of information and the information about your topic. You may write between 1 and 5 sentences on the front of your note card. The back of your note card must contain the title of your source and the page number where you found the information. Quoted Information Note Cards It is important that you learn that it is unethical to present the words of others as if they were your own. In other words, you must not copy information from a book and then type it into your paper as if you had created the sentences yourself. It is not wrong to copy information from a book, as long as you state in your note cards and in your science paper that someone other than you wrote those sentences. The front of your quote cards must contain the information from the source. Remember that it is ok to copy the sentence or paragraph exactly as it appears in the source. The back of your quote card must contain the source title, author, page number where the information was found, the name of the publishing company, the city of publication, and the year of publication. This information is found on the page opposite the title page of books.

Writing Note Cards

Step One Brainstorm topics you can research Step Two Locate sources with information on the topics from Step 1 Step Three Get an index card and make a bibliography card (follow the format below) *Complete this step for each new source

1. Write the name of the book 2. Write the name of the author 3. Write the city, state, or country the book was published in 4. Write the name of the publisher 5. Write the copyright year 6. Write the call number of the book 7. Write the page numbers of the book you will be using If it is the whole book, write that

Step Four Summary note cards reduce information and are written in your own words. Get an index card and write information.

- one fact per card - you do not need to write in complete sentences

1. Write a fact in the middle of the card. 2. Write the last name of the author (if there is no author, abbreviate the title

of the book) and the page number on the bottom of the card (bottom right hand side.)

3. At the top of the card, write a title that describes the fact. Example: If the information describes the appearance of copper, write Copper Appearance on top

Quote note cards A quotation consists of the exact words from a source. On your quote card, put a quotation mark (“) at the beginning and the end of the quote (you may later forget it was a quote). If you are writing something someone other than the author said, you must write down the person’s name on the card.

Parts of the Science Paper Title Page I. Abstract (no more than 250 words) A. Importance (relevance to society, who project will help) B. Purpose/Problem (what you are trying to prove) C. Hypothesis (what you think will happen) D. Materials & Method Summary (2 to 3 sentences) E. Main Findings (results after you tested) F. Concluding Sentence (may be similar to first sentence or be a final statement about your project. II. Introduction (approximately 8 to 10 paragraphs) A. Importance/Relevance of Project B. Purpose/Problem C. Hypothesis D. Summary statements over research/topic (Letters A,B,C, & D above make up your first paragraph) E. Background information 1. Look to your note cards to determine your main points. For each of your

note cards, the information under Roman Numerals will be at least one paragraph long.

NOTE: The topics include in background information: history, past and current studies/experiments, detailed description of types, uses relevance to scientific community, future scientific relevance (how it will improve society), and related research topics. III. Materials & Method (separate into sections, include one sentence introduction) (see sample)

A. Materials B. Method C. Design Weakness D. Variables/Control IV. Results (should be computer generated tables and graphs with a title) (must include 3 to 5 items in this section) A. Illustration 1 1. title 2. one sentence explanation B. Illustration 2 1. see above 2. see above

C. Illustration 3 1. see above 2. see above D. Illustration 4 1. see above 2. see above ILLUSTRATIONS ARE PICTURES, LINE GRAPHS, TABLES, DRAWINGS, ETC... V. Discussion A. Explain each result individually. B. Unusual, important observations. C. Errors/design weaknesses affecting project. D. Concluding sentence. VI. Conclusion A. Restate hypothesis. B. Findings support hypothesis? C. Explain what results mean, interpret findings. D. Final summary of project. E. Suggestions for improving project. F. Main conclusion. VII. Glossary A. List of unfamiliar words. 1. Look for introduction for possible words. VIII. Appendix A. Pictures B. Surveys C. Diagrams IX. Works Cited (bibliography) A. List of sources used to write paper. B. Must follow American Psychological Association (APA) format.

The Appearance of Your Scientific Paper

The presentation of your scientific research paper is very important. You must present your best work and present it in an attractive and organized manner. Use the following guidelines.

1. Type your scientific paper using Microsoft Word. This program is available in the Socorro High School computer lab. Use the grammar feature to correct mistakes. Spell check!

2. All the text must be printed in 12-pt. size. All titles must be printed in 16-pt. size. Use

Times New Roman font only. 3. The title page must have your project’s name, your name, classification, and the date of

presentation. 4. Print your paper clearly.

5. Organize your scientific paper in the order specified in the Table of Contents. 6. Present your paper in a clear plastic cover.

7. Avoid folded pages, smudged ink, and anything else that makes your paper unattractive.

Reprint if you have to.

Title Page

Project Title in 24-pt. bold centered in the center of the page. When writing the title:

- Do not write it in the form of a question - Try to keep it short (under 5 words)

- Make sure it describes your project, but don’t be afraid to be creative.

In the lower right hand corner in 14-pt. bold, include:

- Name (First, Middle Initial, Last) - 1st or 2nd year project (If this is a continuation project from a previous year, type 2nd

Year Project)

- Site where the experiment was done (write the complete address of your home, of

SHS, or of whatever location you used for conducting your experiment)

Table of Contents

After your title page, you should have table of contents. Just as it does in a textbook, the scientific project paper table of contents will help readers locate individual sections easily. The table of contents should list all sections of your paper. It is up to you how you want to arrange the table of contents; make sure that all entries in the page are typed in the same format. The following example presents the title of the page, dots, and the page number where the Abstract is found.

Example:

Abstract…………………………….1 Directions: Table of contents title must be in 14-point bold text, centered at the top of the page. Titles and page numbers must be in 12-point size. The entire page must be justified on both the left and the right sides. Your table of contents must list all of the following sections in this order:

Abstract Introduction

Materials and Methods Results

Discussion Conclusion Glossary Appendix

Works Cited

Abstract

This section of your paper is perhaps the shortest and most important section of your paper. It is usually a maximum of 250 words, and written as one paragraph. You may write in first person. The abstract section serves as a table of contents or map to your entire paper. The Abstract contains a bit of information from each section of your paper. The following outline will help you include all of the necessary information. Suggested Outline: Sentence 1: Importance (relevance to society, who this project will help) Sentence 2: Purpose/Problem (what you’re trying to prove) Sentence 3: Hypothesis (what you think will happen) Sentence 4-6: Materials and Method Summary (2 to 3 sentences) Sentences 7-8: Main Findings (results after you tested) Sentences 9-10: Concluding Sentences (may be similar to the first sentence or serve as

your final opinion or as a summary regarding the project) Remember to limit your Abstract to 250 words.

Introduction This section of the paper is the longest. It is similar to papers you write in English class. The introduction contains all the information you gathered from the research process. When writing this section, think of everything that you have learned about good writing skills. Directions: Write this section in third person. The tone is serious and formal. Do not use contractions or slang. Each paragraph should have between five and seven sentences. Some paragraphs will have more than seven sentences. The body paragraphs of your paper should begin with transitions. Choose a verb tense and be consistent. If you write in present tense, use present tense throughout the paper. If you write in past tense, use past tense throughout the paper. Your paper should include one quote from each of your sources. Remember that TCQC works well for these paragraphs.

I Have My Note Cards, Now What?

Writing the Introduction Outline Terms to Know: Main Idea – The most important point of the paragraph. It explains the central idea that the reader needs to understand. The main idea is also called the topic. Topic Sentence – One sentence that tells the reader what the main idea of the paragraph is. Each paragraph should have a topic sentence. Concluding Sentence – The final sentence in the paragraph that restates the main idea of the paragraph. Step One Separate your note cards into groups by topic. For example, all the cards that tell you what copper looks like would be in one group. All the cards that tell you what copper is used for would be in another group. Each of these groups of note cards will eventually become a different paragraph in your introduction. Step Two Organize your groups of cards. Give each group a title (the title should reflect what all the cards have in common. Example: Group one is titled “Appearance of Copper.” Group two is titled “Uses of Copper”). Decide the best order for your paragraphs. You do this by deciding which group of cards should be discussed first in your paper. Remember that each group of cards equals one paragraph. Step Three Write an outline using Roman Numerals, letters, and numbers. Each topic (group of cards) from step 2 will become a Roman Numeral. Each group of cards needs to be divided into smaller sections; these sections become letters in the outline. Write down the facts that describe each letter. These facts are numbers in you outline. Step three will help you realize which areas need more research.

Step Four Begin writing the introduction section (follow the format below)

1st sentence Start with a topic sentence (look at your Roman Numeral.) 2nd-5th sentences Include facts from note cards (describe your Roman

Numeral.) 6th sentence Concluding sentence, restate the main idea from your first

sentence and introduce your next paragraph’s main idea. Notes: *You may use 3rd person pronouns (he, she, it, one) *Try to use all information from the note cards -remember to use direct quotes as well as paraphrases *Do not use 1st person phrases such as “In my science project” “In this paragraph” “Well, I will talk about”

Editing Your Introduction Your science paper must be closely edited before you print the final copy. Editing eliminates spelling errors and ensures the best science paper possible. The following is an editing checklist. Edit your paper on your own, and then have someone else edit it. Write your initials on the blanks below once you have edited your paper and made sure that all of the following points are correct. It is extremely important that your paper have correct grammar, spelling, etc. ____ Are all words spelled correctly? Have you used the spell-check feature? Are names spelled correctly? _____ Do you have 5-7 sentences in each paragraph? _____ Are most of your sentences compound or complex? _____ Is every sentence a complete thought? _____ Is every idea clearly explained? Are the ideas in your paper related to each other? _____ Are your sentences grammatically correct? Did you fix the errors found by the grammar-check feature? _____ Do you have transitions? Are they followed by a comma and used to introduce new paragraphs? _____ Have you avoided first person pronouns? All your writing in the introduction must be in third person. _____ Are all your verbs in the same tense? Write either always in present tense or always in past tense. _____ Do you have one quote from every source? _____ Is the tone of your paper serious and professional? Have you avoided slang and a friendly tone?

Adding Quotes to Your Introduction Most of the sentences in your science paper must be sentences that you created yourself. They may be sentences that you created by summarizing information from your sources. It is a good idea, however, to add some quotes to your science paper. Quotes are sentences that were copied directly from the source. Remember that it is ok to copy sentences directly out of the source and into your paper as long as you state clearly that someone, other than you, wrote those words. Quotes must be about the topic that is being discussed in the paragraph. You must have one quote from every source. Once you have found the information that you want to quote and have found the perfect place for your quote, you are ready to do In-Text Citation. This sounds complicated, but it is actually very easy. You need to know the author of your quote and the page number where you found the quote. You should have this information written on your quote card. Follow these easy steps.

1. Decide how long your quote is. Is it a few words? A sentence? A paragraph? 2. Type your quote into the paper.

If your quote is not a complete sentence, put quotation marks around the information. At the end of the sentence, type the author’s last name and the page number where the quote was found. Surround this information with parenthesis. Place a period after the closing parenthesis; this will serve as the ending punctuation for your sentence. Example (Lopez 45). If your quote is an entire sentence, you do not need quotation marks. Simply add the bibliographical information in parenthesis at the end of your sentence. If your quote is a complete paragraph, add the bibliographical information at the end of the last sentence. Remember that you only need one punctuation mark at the end of the sentence and that it belongs after the last parenthesis. Remember to do this for all quoted information.

Materials and Methods This section of your paper deals with the experiment process, the items and steps that you used in your experiment. It is necessary to write down all the supplies that were used to complete the experiment as well as a step-by-step listing of the process used. Your goal in creating this section of the paper is to make it possible for someone else to replicate your entire procedure without any problems. A sample Materials and Methods page is presented here for you. Directions: At the top of the page, type the words ‘Materials and Methods’ (capitalize the major words) in 14-point bold, centered text. In 12-point bold text, write the word ‘Materials’ next to the left margin. Using 12-point text, make a list of every item that you used in the experiment. You may number this list if you wish. Be sure to include the quantities of each item. Repeat the typing for the ‘Methods’ section Along the left margin, type the words ‘Design Weakness’ in 12-point, bold text. Write a one-sentence explanation of the weakness in the project. Along the left margin, type the word ‘Variables’ in 12-point, bold text. List all of your variables as they appear on your checked research plan.

SEE A SAMPLE ‘MATERIALS AND METHODS’ ON THE NEXT PAGE

This is a sample; please read the instructions on the previous page before continuing.

Materials and Methods

Materials For this experiment, you need:

1. One 1-liter bottle 2. 65 grams of salt 3. 50 liters of water 4. Triple beam balance 5. 10 people from the ages of 14 to 20

Method To complete this experiment, follow these steps:

1. Fill a 1-liter bottle with water. 2. Give the water to your test subject and instruct him/her to swish the water in his/her

mouth. 3. Record whether he/she tasted salt or not. 4. Empty the water and fill again. 5. Add 1.5 grams of salt to the water and shake 6. Give the water to your test subject and instruct him/her to swish the water in his/her

mouth. 7. Record whether he/she tasted salt or not. 8. Repeat steps 4-6 with 2.5 grams, 0.5 grams, and 2.0 grams of salt. 9. Repeat steps 1-6 with the 9 other test subjects. 10. Record results.

Design Weakness If a test subject did not fully rinse out his/her mouth, residue from other foods may have affected the tasting.

Variables All variable are controlled except for the swishing of the water in the mouth.

Results

This section of the paper describes what happened after you tested your problem. It is not written in paragraph form. Instead, you take the data collected and find a visual way to present it. For example, you cold use a table, before-and-after diagram, circle graph, bar graph, line graph, etc... Include a title for each illustration and a one-to-two sentence explanation of what the reader is seeing. Also, if a key is needed, do not forget to include it. Try to use a color printer; otherwise, expect to color your illustration to make them look better.

Discussion

In this section of the paper, describe your findings in paragraph form. Include all results. For instance, if you tested 10 people, you must describe what happened to each of those ten people after testing. Use the results section of your paper to assist you. Directions: Explain each result individually and in great detail. Describe unusual and important observations. State how errors or design weaknesses affected the project. Write a concluding sentence which summarizes your main findings.

Conclusion Using some elaboration, A. Restate hypothesis. B. Findings support hypothesis? C. Explain what results mean, interpret findings. D. Final summary of project. E. Suggestions for improving project. F. Main conclusion.

Glossary

Any scientific terms that may be unfamiliar to the average reader must be defined in a glossary. The glossary will be part of your scientific paper. Use the following guidelines.

1. Type the term in 12-pt. bold text. 2. Add a hyphen after the term. 3. Type the definition in 12-pt. plain text.

The word Glossary should be typed at the top of your list of words, as a title to the page. Use 16-point, bold text.

Appendix The appendix section of your paper includes information that did not fit in your introduction, but is still important to your project. For example, perhaps your project is about the effects of various beverages on teeth. In the appendix section, you may want to include the ingredients found in a Coca-Cola can or maybe a drawing of the teeth in your mouth or even a diagram describing the process of how teeth become stained. Overall, the appendix provides extra information that will help the reader understand your project better. You may choose to include charts, tables, documents, pamphlets, sheets, interview questions, time lines, or the process used to set up your project (ex: arrangement of plants studied.) Copies may be used, but they should be clear and easy to understand. Directions: Provide a title page for this section of the paper. The word Appendix (capitalized) should be typed in 16-point bold text and centered in the middle of the page. Place only one item on each sheet of paper. Write a title and brief explanation describing what the reader is seeing. 1-3 sentences are enough. Tips: Be neat if you are cutting, color to enhance the drawings etc; don’t forget to label all items, and if the item is being copied, enlarge it.

Works Cited Page

Terms to Know: Bibliography – (n.) A list of the sources that you used to find information. The difference between a bibliography and a Works Cited page is that the Works Cited page lists only the sources that provided quotes for your scientific paper. This page contains the publishing information of about every source that you used in creating your research paper. The following information applies to Works Cited pages for all research papers. Use this information for English class, history class, etc. Save this information for college! Before beginning your Works Cited page, you must collect the following information about every source that you used. The information should be on your bibliography cards.

- complete title - full name of author(s) - city of publication - publishing company - year of publication - page numbers that you used (if applicable) - access date for internet information (if applicable)

The title of your page should be Works Cited. This should be underlined and in bold. It should not have quotation marks. In your Works Cited page, every parentheses, period, comma, etc. is very important. Equally important is that you follow the guidelines created by the APA. Please refer to your SHS Student Agenda for examples of APA citations.

Presenting to the Judges

On average, you will have two to three judges whose job it is to find out how knowledgeable you are regarding your topic. Impress the judges with your knowledge, confidence, and speaking skills. Answer questions and ask questions. If you can’t answer the question, consider three things. 1. Is the wording of the question throwing you off? If so, ask the judge to rephrase

the question. 2. Do you think that the question is irrelevant (has no connection) to your project? Again, if this is the case, ask the judge to clarify or restate the question. 3. The one thing you don’t want to do is say, “I don’t know.” When speaking, pay close attention to the following: Introduce yourself. Make the judges feel welcome. Let the judges know that you appreciate their time spent with you. At the end of your presentation, say, “Thank you.” Have good eye contact. -Look directly at the judges, not at your research paper or backboard. Keep hands out of pockets, away from hair or jewelry. Maintain good posture (stand straight and don’t fidget). -Proper posture signals confidence. Speak loudly and clearly. -Refrain from mumbling, speaking too fast, etc... Show your knowledge. -If a judge does not ask about an important aspect of the project, mention it yourself. If the need arises, refer to your paper or backboard to answer a question. -Otherwise, do not depend on them to answer questions. This will show the judges that you know your material. Have a serious tone while speaking or asking questions. (Be professional!) -Don’t laugh or look at others while speaking with the judges. Refrain from saying, “uhms, uhs, likes”, etc... Most importantly, practice, practice, and practice. -Know what you’re going to say well in advance. It’s a good idea to have different people ask you sample questions regarding your project.

Sample Journal Article:

THE EFFECTS OF ARTIFICIAL SOLAR RADIATION ON WIND-STRESSED TUFTED TITMICE (PARUS BICOLOR) AND CAROLINA CHICKADEES (PARUS CAROLINENSIS) AT LOW TEMPERATURES

JAMES T. WOOD and SHELDON I. LUSTICK

THE EFFECTS OF ARTIFICIAL SOLAR RADIATION ON WIND-STRESSED TUFTED TITMICE (PARUS BICOLOR) AND CAROLINA CHICKADEES (PARUS CAROLINENSIS) AT LOW TEMPERATURES

JAMES T. WOOD and SHELDON I. LUSTICK

Department of Zoology, The Ohio State University, Columbus, OH 43210, USA.

Telephone: (614) 292-8088

(Received for publication 29 July 1988)

Abstract-l. Changes in metabolic rates and behavior were observed in tufted titmice (Parus bicolor) and Carolina chickadees (Parus carolinensis) exposed to varying conditions of artificial solar radiation, wind, and temperature in a wind tunnel experiment.

2. During the wind-on condition, both species showed a significant decrease in mean metabolic rates in the high radiation treatments when compared to the low radiation treatments (P < 0.05).

3. Titmouse orientation, posture and level of activity were significantly affected by radiation and wind conditions. 4. Metabolic rates observed in the wind tunnel treatments without wind and at low radiation did not significantly differ

from similar standard metabolic (black box) treatments (P > 0.05). 5. Activity levels did not appear to directly affect metabolic rates observed in the wind tunnel treatments.

INTRODUCTION

Animals that inhabit Ohio throughout the winter are often exposed to harsh environmental conditions. Average temperatures falling below 0°C and wind velocities reaching 50 km/hr can result in high energy costs for organisms during the winter months. These energy costs can be particularly severe for small animals because of their large surface area to volume ratios. However, several species of birds and mammals are seen moving about regularly throughout the Ohio winterland. This investigation dealt with the way in which two winter residents, the tufted titmouse (Parus bicolor),

and the Carolina chickadee (Parus carolinensis), reacted behaviorally and physiologically to laboratory simulations of winter environmental conditions.

Birds living in cold environments have developed several energy conserving mechanisms. They drop their body temperature to reduce heat loss at night or during stressful periods (Omhart and Lasiewski, 1971; Budd, 1972; Mayer et al., 1982; Blem, 1984; Chaplin et al., 1984). Winter birds can behaviorally take advantage of solar radiation (Lustick, 1984, Lustick et a1.,1978,1979; Morton, 1967; Ohmart and Lasiewski, 1971; De Jong, 1976) as well as choose between microhabitats (Kendeigh, 1961; Pitt, 1976; Grubb, 1977, Kelty and Lustick,1977). These are all examples of means by which birds interact with what Porter and Gates (1969) describe as a four-dimensional climate space or microclimate that surrounds the animal. As Porter and Gates suggest, there are four independent physical variables acting simultaneously upon an animal and affecting that animal's energy costs. This investigation dealt with the physiological and behavioural responses to three of these factors: temperature, wind velocity and solar radiation. Humidity, the fourth factor, was controlled at a minimum value.

Moen (1973) demonstrated that convection may effectively remove the radiant heat energy absorbed by the hairs of mammals. Walsberg et al. (1978), working with bird skins, found that thermal resistance and heat gained from simulated solar radiation, were significantly affected by forced convection. Mayer et al. (1979), after their investigation of energy-controlled behavior in Carolina chickadees, speculated that it was highly probable that thermal benefits from solar radiation could negate some of the effects of low air temperatures and wind. Neal (1976), working with eastern chipmunks (Tamias striatus) in wind tunnel experiments, found that artificial solar radiation partially negated wind induced increases in metabolic rate. The objective of this study was to observe and quantify changes in metabolic rates and changes in behavior in response to varying conditions of artificial radiation, wind and low temperatures.

MATERIALS AND METHODS

Eighteen winter-acclimatized tufted titmice and eight Carolina chickadees were collected from November to April 1986-87. The animals were kept at natural photoperiod and temperature. After a 7-day adjustment period, the birds were

exposed to a series of wind (0, 4.7 km/hr), temperature (0, - 7°C), and artificial solar radiation (306.4, 773.8 W Jm2 ) combinations. The artificial environmental conditions were simulated in an open-circuit system wind tunnel/metabolic chamber modified from the design of Neal (1976; Fig. 1). The distance of the light source from the tunnel was adjusted to approximate the incoming solar energy that a bird would experience on either a sunny or a cloudy winter day.

The incoming radiation was aligned perpendicular to the direction of the wind at approximately 25° above the horizon. Each bird was exposed to all eight combi-nations.

In order to minimize holding and handling time, treatments that differed only in wind condition were combined into one test period. This was done by running

the wind-on and wind-off treatments sequentially. The presentation order of the four test periods and the wind order in each test period were randomly assigned.

Each animal was tested every other day between 08:00 and 17:00 hr. Before a test period, each titmouse or chickadee was placed in a holding tunnel in the animal room for a 1.5 hr or 30-min fast, respectively. The animal was then placed in the testing tunnel and exposed to the randomly assigned temperature, wind and radiation conditions. Once the tunnel was sealed the bird was allowed to acclimate to this treatment for 30 min. Following the adjustment period, the bird was then monitored for 20 min. After observing the bird for 20 min, the wind condition was changed, creating a new treatment. For another 20 min the bird was allowed to adjust to this new condition. It was then again monitored for 20 min. Metabolic and behavioral data were collected throughout each 20 min observation period. Oxygen consumption, an index of metabolism, was measured using an open flow Electrochemistry S-3a Oxygen Analyzer (Depocas and Hart, 1957). The OZ consumption was recorded once every minute during the 20-min observation periods. An estimated value of 4.8 kcal /l of OZ was used to calculate metabolic rate for the fasted birds (Bartholomew, 1982). Changes in each bird's orientation, posture, and level of activity was monitored remotely by a video camera that was placed beside the tunnel. During each 20 min observation period, it was recorded once every 15 sec whether the bird's body axis was aligned parallel or perpendicular to the wind sources. The number of perch changes in 10 sec was recorded every half minute. Since an animal could be active without changing perches, it was recorded once every 15 sec whether or not an animal was completely immobile (i.e. no gross body movements), and these values were then used to calculate the percent time active. Panting or any unusual behavior was also noted.

After completing the four test periods, nine of the titmice and all eight of the chickadees were tested for standard metabolism (black box treatments) at 0° and -7°C. Temperature was the only variable. Following a 20 min adjustment period, oxygen consumption readings were recorded for 20 min. The next day, the bird would be exposed to the other black box temperature treatment.

The metabolic data were examined using the Statistical Analysis System (SAS 1985). Tukey's multiple comparison test with repeated measures error term and an experimental wide error rate of P < 0.05 was used to compare treatments and combinations within a species. The behavioral data within a species were analysed using a distribution-free multiple comparison test based on Friedman Rank Sums blocking by test bird (Hollander and Wolfe, 1973). Again the error rate was set at the P < 0.05 level.

RESULTS

Significant differences between radiation, wind and radiation/wind combinations were observed for both titmice and chickadees (Figs 2-4). Titmice also showed a significant effect due to temperature. Chickadees showed no significant differences involving temperature. For titmice at 0°C and low radiation, the mean metabolic rate with the wind on was significantly higher than it was during the other three interaction treatments (Fig. 2). At - 7°C and low radiation, the mean metabolic rate with the wind on was again significantly higher than the mean metabolic rate of the other three combinations (Fig. 3). Also at this temperature, the mean metabolic rate with the wind off and at low radiation was significantly higher than the mean metabolic rate observed at either the wind on or wind off settings at high radiation. No significant difference in mean metabolic rate was found between wind settings at high radiation.

Similar results were found with the chickadees. However, in this case, as there was no significant difference found between the 0 and - 7°C treatments readings taken at 0°C and - 7°C for each particular wind-radiation combination were grouped together for analysis. The results of this chickadee test were the same in pattern as the - 7°C treatments of the titmice (Figs 3 and 4).

In the comparisons of the number of perch changes per minute, titmice showed a significant effect between radiation/wind interaction treatments. The number of perch changes per minute was significantly less in the high radiation, wind-on treatments (38) compared to high radiation, wind-off treatments (46). Chickadees showed no significant

differences in number of perch changes. No significant difference in mean number of perch changes per minute were seen between birds. No significant differences in percent time active were found between treatments for either species. The wind direction was perpendicular to the direction of incoming radiation. The percent of time a bird spent either facing the wind or turning directly away from the wind [maximizing its characteristic dimension (Mugaas and King, 1981) and thus mini-mizing the effect of wind] was compared across the four radiation/wind combinations. Titmice spent a significantly larger percentage of their time in this position (long axis parallel to the wind) with the wind on at high or low radiation compared to the high radiation wind off combination.

The standard metabolic treatments were used to estimate the metabolic rates at 0°C and -7°C without artificial radiation, wind or bird movement (Figs 2-4). A paired t -test was used to compare black box metabolic rates with those observed at each temperature in wind-tunnel treatments with low radiation and wind off. No significant differences were found for the nine titmice (P = 0.93) or eight chickadees (P = 0.90) tested.

DISCUSSION It has been found that eastern chipmunks, exposed to artificial solar radiation, experienced a reduction in some of the

costs of convective heat loss (Nea1,1976). The same can be said about titmice and chickadees. Both titmice and chickadees in the wind-on condition at high radiation showed a significantly lower mean metabolic rate than they did under the same wind conditions with decreased radiation (Figs 2-4). The wind-stressed animals were able to take advantage of the additional available radiation energy to maintain a lower metabolic rate.

The low radiation condition offered little additional energy to the bird. Long-wave radiation from chamber and environmental room walls accounted for approximately 99% of the overall radiation experienced by the bird at the low radiation setting. The level of radiation from the light source at low radiation had little effect beyond allowing the bird to see. No additional radiation (or rather a zero radiation level) was assumed at the low radiation setting. In the high radiation setting at least an additional 467.4 W /M2 were made available to the animal. It is important to remember also that the radiation sources were set at an angle of incidence 25° above the horizon. By changing posture, the bird had the ability to decrease the angle of incidence relative to its body. With the decrease in the angle of incidence, the radiation source became more perpendicular to the bird's body surface. In this position more energy could be absorbed by the bird. The wind velocity was set at either zero or 1.3 m /sec. The effects of high radiation alone and wind alone were added to the results of treatments that had no additional radiation and no wind. This was done by adding the net increase of mean metabolic rates due to wind at the low radiation setting, to the net decrease in mean metabolic rate due to high radiation at the wind-off setting. The results were then added to the mean metabolic rate at low radiation with no wind. These results were then compared to the mean metabolic rates observed at high radiation with the wind on (Table 1). For both titmice and chickadees the measured mean metabolic rate was approximately 80% of the predicted value. Neal (1976) made similar predictions with the eastern chipmunks and found that his measured metabolic rates averaged 94% of the predicted values. This investigation differed from Neal's experiment in that it was designed to allow the animals some behavioral flexibility in dealing with the conditions in each treatment. The flexibility in behavior may help explain the differences between predicted and observed metabolic readings. The observed changes in behavior strongly suggest that the animals' ability to alter its orientation, posture, or level of activity had an effect upon its energy exchange.

Changes in behavior that the animals might use to maintain thermal balance were also quantified. It was expected that an animal would try to minimize energy costs due to wind-induced convection by orienting itself in such a way as to maximize its characteristic dimension. The larger a bird can make its characteristic dimension, the less disruption will occur in its thermal boundary layer. By maintaining a thick thermal boundary layer between the environment and its body surface, a cold-stressed

animal reduces energy loss to the environment. By orienting its long axis to the wind, a bird would maximize its character-istic dimension. Because the radiation source was perpendicular to the wind, a bird in this position would also be maximizing its surface area exposed to incoming radiation. In this position the bird could minimize the effects of the wind and at the same time maximize the effects of the radiation. In the comparison among radiation/wind combinations, titmice were found to spend a significantly higher percent of their time in this position during the wind-on combinations compared to the wind-off combinations at high radiation, thus minimizing the effects of the wind and maximizing the effects of radiation. It appears that this difference in orientation was not totally attributed to wind stress. At the high radiation level with no wind, too much radiation may have had an effect on behavior. For at least part of the time in the high radiation, wind-off and 0°C treatments, each bird was observed panting and/or posturing its body (i.e. wing drooping, lowering the head and adjusting its posture apparently to increase the angle of incidence etc.) in such a way as to reduce radiation effects. Seven of the 26 birds were observed panting in the high radiation, wind off and - 7°C treatments. By orienting its body axis parallel to the radiation source, a bird would minimize body surface area exposed to incoming radiation. The increase in the time spent aligned with the radiation source (perpendicular to the wind source) may have occurred as an animal attempted to deal with heat stress.

Posture is another means by which the birds may behaviorally thermoregulate. Most cold-stressed birds erect their feathers, tuck their beak and sit on their feet (Lustick, 1984). In an attempt to measure posture changes the percent time active was recorded for each treatment. It was expected that when the birds reduced gross body movements they would assume the postures mentioned above. It became evident well into the experiment that the birds were quite variable in the ways that they would posture. Some titmice did become ptilo-erect, tuck their head, and sit on their feet, but others did not seem to change the size or shape of their surface area even when still. Heat-stressed birds were often observed drooping their wings and lowering their head. As the recordings of these types of changes in posture were made anecdotally, it is safe to say only that variations and patterns were observed and that it appears that posture was a behavioral tool used by these birds to help maintain heat balance. As far as percent time active is concerned, no significant difference between treatments was observed for either species.

Heat stress may also help explain differences observed in the number of perch changes per min among radiation/wind combinations. Titmice showed a significantly larger number of perch changes in the high radiation, wind-off treatments compared to the wind-on treatments of the same radiation level. All birds were seen panting in the former treatment, and none were seen panting in the latter. Both treatments were at temperatures well below thermal neutrality. In the high radiation, wind-off treatments, the titmice were panting to dump heat. With the wind on, the birds apparently took advantage of the forced convection to remove the excess heat so that panting was no longer necessary. It is possible that a lowerstressed, energy-balancing orientation and posture were available with the wind on and not with the wind off. It was speculated that the higher titmouse activity level observed with the wind off was due to the animal increasing attempts to escape from this stressful environment.

It is also important to note that the amount of activity in this experiment appeared to have little effect on observed metabolic rates. Standard metabolic treatments were used to demonstrate the possible overall contribution of activity to the observed metabolic rates. Birds are relatively motionless in a blackened chamber. Since no significant differences were seen for both titmice and chickadees between black box metabolic rates and metabolic rates of similar treatments in the wind tunnel (Figs 2-4), it appears that the activity levels seen in the low radiation and no wind treatments had little effect on the observed metabolic rates. Ketterson and King (1977) found locomotor activity to have little effect on 02 consumption in laboratory-fasted and temperature-stressed white-crowned sparrows. They felt that it may be possible for fasting birds to use activity-generated heat to help in thermal regulation. Yet, as Bartholomew (1982) points out, for small animals this additional heat may not be made available or be of any thermoregulatory significance. The large surface area-to-volume ratio in small animals would be greatly affected by disturbances in their boundary layer or increased circulation at the body surface. It is more probable that the increase in activity that Ketterson and King (1977) observed was due to the bird increasing efforts to escape to a better microclimate or possibly increasing foraging behavior. Changes in the level of activity had no significant effect on metabolic rates. For titmice, the increase in the level of activity in the high radiation, no wind conditions, was most likely due to an increased effort to avoid the radiation.

It was interesting to note that no significant differences were found between wind-on or wind-off conditions at high radiation for titmice or chickadees (Figs 2-4). It is possible that at this high radiation level the birds may have dropped to the lowest possible metabolic rate achieved under these experimental conditions. The high radiation appeared also to reduce some of the costs of low temperature. The mean metabolic rates in the high radiation treatments were found to be lower than the black box treatments though the differences were not found to be significant. It is also possible that the metabolic rates at high radiation with no wind were actually increased rather than decreased by the additional energy. It is known that metabolic rate increases with panting. This possible reaction to heat stress would have also affected the predictions made earlier by causing an underestimation of the effect of additional radiation.

Wind-stressed titmice and chickadees at low temperature do have the ability to gain benefit from additional radiation, particularly short-wave radiation. In the natural environment, an understanding of this ability might be useful in explaining observed foraging behavior. Particular wind speeds on a cloudy day or in shade areas may impose restrictions that would be removed with the appearance of the sun. There is a continuum of possible orientations and postures from which a bird can choose. As was shown in this experiment, the birds can behave opportunistically and pick an orientation or posture according to the situation. The increases in activity seen in this experiment were found to have no direct effect on metabolic rates, but it is highly unlikely that these small birds could use locomotor muscle activity to generate heat for the purpose of thermoregulation. If the animal is stressed by environmental conditions, it may first adjust posture and orientation. If these adjustments are not sufficient, then it will try to find a more suitable microenvironment.

REFERENCES

Bartholomew G. A. (1982) Energy metabolism. Animal Physiology: Principles and Adaptations (Edited by Gorden M. S.), 3rd edn, pp. 57-111. Macmillan, New York.

Blem C. R. (1984) Mid-winter lipid reserves of the Goldencrowned kinglet. Condor 86, 491-492. Budd S. M. (1972) Thermoregulation in black-capped chickadees. Am. Zool. 12, 33. Chaplin S. B., Diesel D. A. and Kasparie J. A. (1984) Body temperature regulation in red-tailed hawks and great horned owls:

response to air temperature and food deprivation. Condor 86, 175-181. De Jong A. A. (1976) The influence of simulated solar radiation on the metabolic rate of white-crowned sparrows. Condor 78, 174-

179. Depocas F. and Hart J. S. (1957) Use of the Pauling oxygen analyzer for measurements of oxygen consumption of animals in

open-circuit systems and in short-leg closedcircuit apparatus. J. appl. Physiol. 10, 388-392. Grubb T. C. Jr (1977) Weather-dependent foraging behavior of some birds wintering in a deciduous woodland: horizontal

adjustments. Condor 79, 271-274. Hollander M. and Wolfe D. A. (1973) Nonparametric Statistical Methods. John Wiley & Sons, New York. Kelty M. P, and Lustick S. I. (1977) Energetics of the starling (Sturnus vulgaris) in a pine wood. Ecology 58, 1181-1185. Kendeigh S. C. (1961) Tolerance of cold and Bergmann's rule. Auk 86, 13-25. Ketterson E. D. and King J. R. (1977) Metabolic and behavioral responses to fasting in the white-crowned sparrow (Zonotrichia

leucophrys gambelii ). Physiol. Zool. 50, 115-129. Lustick S. (1984) Thermoregulation in adult sea birds. In Sea Bird Energetics (Edited by Whittow S. and Rahn H.), pp. 183-201.

Plenum Press, New York. Lustick S., Battersby B. and Kelty M. (1978) Behavioral thermoregulation: orientation towards the sun in herring gulls. Science 200,

81-83. Lustick S., Battersby B. and Kelty M. (1979) Effects of insolation on juvenile herring gull energetics and behavior. Ecology 60, 673-

678. Mayer L., Lustick S. and Grubb T. Jr (1979) Energetic control of behavior: foraging in Carolina chickadees. Comp. Biochem. Physiol.

63A, 577-579. Mayer L., Lustick S. and Battersby B. (1982) The importance of cavity roosting and hypothermia to the energy balance of the

winter acclimatized Carolina chickadee. Biometeorology 26, 231-238. Moen A. N. (1973) Wildlife Ecology. W. H. Freeman, San Francisco. Morton M. I. (1967) The effects of insolation on the diurnal feeding pattern of White-crowned sparrows (Zonotrichia leucophrys

gambelii ). Ecology 48, 690-694. Mugaas J. N. and King J. R. (1981) Annual variation of daily energy expenditure by black-billed magpie: a study of thermal and

behavioral energetics. In Studies in Avian Biology, No. 5. Cooper Ornithological Society. Neal C. M. (1976) Energy budget of the Eastern chipmunk (Tamias striatus) convective heat loss. Comp. Biochem. Physiol. 54, 157-

160. Ohmart R. D. and Lasiewski R. C. (1971) Road-runners: energy conservation by hypothermia and absorption of sunlight. Science

172, 67-69. Pitts T. D. (1976) Fall and winter roosting habits of Carolina chickadees. Wilson Bull. 88, 603-610. Porter W. P. and Gates D. M. (1969) Thermodynamic equilibria of animals with environment. Ecol. Monogr. 39, 227-244. SAS Institute Inc. (1985) SAS User's Guide: Statistics, 5th edn. SAS Institute Inc., Cary, North Carolina. 956 pp. Walsberg G. E., Campbell G. S. and King J. R. (1978) Animal coat color and radiative heat gain: a reevaluation. J. comp. Physiol.

126, 211-222.

Sample Journal Article:

Hyperventilation before Resistance Exercise: Cerebral Hemodynamics and

Orthostasis

STEVEN A. ROMERO and WILLIAM H. COOKE Laboratory for Applied Autonomic Neurophysiology, The University of Texas at San Antonio, San

Antonio, TX

Copyright @ 200 by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited.7

Hyperventilation before Resistance Exercise:Cerebral Hemodynamics and Orthostasis

STEVEN A. ROMERO and WILLIAM H. COOKE

Laboratory for Applied Autonomic Neurophysiology, The University of Texas at San Antonio, San Antonio, TX

ABSTRACT

ROMERO, S. A. and W. H. COOKE. Hyperventilation before Resistance Exercise: Cerebral Hemodynamics and Orthostasis. Med. Sci.

Sports Exerc., Vol. 39, No. 8, pp. 1302–1307, 2007. Hyperventilation performed by athletes during preparation for resistance exercise

might contribute to reports of postexercise orthostatic instability. Purpose: To test the hypothesis that post–resistance exercise

orthostatic instability is associated with exaggerated reductions of cerebral blood-flow velocity after hyperventilation. Methods: We

recorded the ECG, end-tidal CO2, beat-by-beat finger arterial pressure, and cerebral blood-flow velocity in 10 healthy subjects. Subjects

performed 10 repetitions of recumbent leg press using resistance equivalent to 80% of their six-repetition maximum during three

separate trials (randomized): 1) no prior hyperventilation (NOHV); 2) after hyperventilation to an end-tidal CO2 of 3% (HV3%); and 3)

after hyperventilation to an end-tidal CO2 of 2% (HV2%). After exercise, subjects stood upright for 10 s and rated symptoms of

lightheadedness on a scale of 1 (none) to 5 (faint). Results: Mean cerebral blood-flow velocity (CBFVMEAN) increased by 12%

during exercise after NOHV and decreased by 14 and 25% during exercise after HV3% and HV2% (all P G 0.0001). During standing,

mean arterial pressure (MAP) decreased by 96 mm Hg and CBFVMEAN decreased by 41 cmIsj1 (pooled across conditions; all P G

0.0001). Absolute reductions of CBFVMEAN during standing were greater after HV2% compared with both NOHV and HV3% (P =

0.003). Ratings of perceived lightheadedness during standing increased with prior hyperventilation (P = 0.02) and correlated to

the magnitude of reductions in MAP (r = 0.51; P = 0.003) and CBFVMEAN (r = 0.37; P = 0.04). Conclusions: Hyperventilation

before lower-body resistance exercise exacerbates CBFVMEAN reductions during standing. Increased symptoms of orthostatic instability

are associated with the magnitude of reductions in both MAP and CBFVMEAN. Key Words: STRENGTH TRAINING, CEREBRAL

BLOOD-FLOW VELOCITY, ORTHOSTATIC TOLERANCE, CEREBRAL AUTOREGULATION

Under quiet, resting conditions, cerebral blood flowis maintained constant through autoregulation andis not dependent on modulation by systemic

arterial pressure (13). During mild cycle ergometry exer-cise, blood pressure increases but remains within thecerebral autoregulatory range, resulting in unchangedcerebral blood flow (6). However, during more intensecycle ergometry exercise, arterial pressure and pulsepressure increase substantially, along with cerebral blood-flow velocity (11). The effects of exercise intensity oncerebral blood-flow velocity during resistance exercise areless clear. When arterial pressures increase moderatelyduring the double leg press, mean cerebral blood-flowvelocity (CBFVMEAN) is unchanged (4). However, arterialpressures on the order of 450/380 mm Hg have beenreported during high-intensity weight lifting (10), and a

direct linear association between the amount of weightlifted and the reduction of cerebral blood-flow velocity hasbeen demonstrated (3).

Changes in cerebral blood-flow velocity during resistanceexercise could be associated with a number of factors,including body position, the potential for Valsalva straining,or changes in arterial CO2 content (4,8). Cerebral blood-flow velocity is unchanged during isometric handgripexercise in subjects who maintain eucapnic ventilation, butit decreases in subjects who hyperventilate during exercise(8). Reductions of cerebral blood-flow velocity duringresistance exercise may put weight lifters at risk forpostexercise lightheadedness and orthostatic instability.Because hypocapnia constricts cerebral vessels (13), symp-toms of dizziness or outright ‘‘weight lifters_ blackout’’could be linked to the degree of hyperventilation performedbefore resistance exercise (1).

Although anecdotal evidence suggests that immediatepostexercise orthostatic instability experienced by someathletes may be related to a preexercise routine that includesvoluntary hyperventilation (1,4), this notion has not beentested experimentally. Therefore, the purpose of this studywas to test the hypothesis that hypocapnia induced withhyperventilation before heavy lower-body resistive exerciseexacerbates reductions of CBFVMEAN and increases acutesymptoms of orthostatic instability.

Address for correspondence: William H. Cooke, Ph.D., Department ofHealth and Kinesiology, The University of Texas at San Antonio, 1 UTSACircle, San Antonio, TX 78249; E-mail: william.cooke@utsa.edu.Submitted for publication December 2006.Accepted for publication March 2007.

0195-9131/07/3908-1302/0MEDICINE & SCIENCE IN SPORTS & EXERCISE�Copyright � 2007 by the American College of Sports Medicine

DOI: 10.1249/mss.0b013e3180653636

1302

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IENCES

Copyright @ 200 by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited.7

METHODS

Subjects. Before the recruitment of subjects, a poweranalysis was run to estimate the minimum number ofsubjects required to test our hypothesis. Recent unpublisheddata have shown that subjects who experience orthostaticinstability when they stand up after a period of sustainedsquatting on their heels (squat–stand test) decrease theirCBFVMEAN about 10 cmIsj1 more so than subjects whodo not experience orthostatic instability (V.A. Convertino,personal communication, 2006). According to this obser-vation, we chose to estimate an appropriate sample size forthe current study on the basis of the magnitude of expectedchange in CBFVMEAN during standing after leg-pressexercise as our continuous variable. For CBFVMEAN, weused a Student_s t-based algorithm to estimate that a samplesize of N = 9 would allow a true least difference of interestof 10 cmIsj1 with an expected standard deviation of5 cmIsj1 to be detected by a two-tailed test P G 0.05 with80% power (15).

Five males and five females (age 26 T 4.4 yr; height170 T 6.7 cm; weight 72 T 8.9 kg; means T SD) volunteeredto participate in the study. Subjects were all experiencedweight trainers and were currently participating in an activeweight-training program. Because of the potential influ-ences on autonomic blood pressure regulation, subjectsabstained from exercise, caffeine, and alcohol at least 12 hbefore experimentation. This research study was approvedby the institutional review board of the University of Texasat San Antonio, and written informed consent was obtainedfrom all subjects before experimentation.

Study protocol. Before testing, subjects first per-formed sets of six repetitions with progressively increasingresistance on a recumbent leg-press machine (Cybex,Medway, MA) to establish their six-repetition maximum(6RM). Eighty-five percent of a subject_s 6RM was takenas the subject_s estimated 10-repetition maximum (10RM).

Subjects were instrumented with an ECG to recordcardiac electric potentials (Harvard Apparatus, Holliston,MA), a finger plethysmography device to record beat-by-beat finger arterial pressure (Finometer, Finapres MedicalSystems, Arnhem, the Netherlands), a facemask connectedto a sampling line to assess end-tidal CO2 (Gambro,Enstrom, Sweden), and a 2-MHz transcranial Dopplerultrasound probe positioned at a constant angle over thetemporal window to record cerebral blood-flow velocityfrom the middle cerebral artery (MultiDop T, DWLElectronics, Sipplingen, Germany).

Subjects rested quietly on the recumbent leg-press devicefor 1 min to establish preexercise (baseline) values; then,they performed three sets of exercise at their calculated10RM on three different occasions (in randomized order):1) no prior hyperventilation (NOHV); 2) after voluntaryhyperventilation to an end-tidal CO2 of 3% (HV3%); and 3)after voluntary hyperventilation to an end-tidal CO2 of 2%(HV2%). Subjects were positioned so that they could not

see the output from the CO2 meter, and they were promptedto begin exercise by one of the investigators when end-tidalCO2 reached the required level. Subjects were instructed toavoid Valsalva straining during exercise, and lack ofValsalva straining was confirmed with breath-by-breathmonitoring of CO2. After each set of exercise, subjectsstood immediately upright for approximately 10 s and ratedtheir symptoms of lightheadedness (if any) using the ratingscale of Convertino et al. (2). The nomogram used bysubjects to rate symptoms was scaled as follows: 1) none,2) mild, 3) moderate, 4) severe, and 5) faint. After ratingany symptoms, subjects returned to the recumbent positionin the leg-press device and rested for 1 min beforeperforming another set.

Data acquisition and analysis. Data were sampled at500 Hz and recorded directly to computer with commercialhardware and software (WINDAQ, Dataq Instruments,Akron, OH). Data were then imported into a commercialanalysis program (WinCPRS, Absolute Aliens, Turku,Finland). R waves generated from the ECG signal weredetected automatically, and then the accuracy of thecomputer detection algorithm was checked manually forerrors and edited as required. Diastolic (DAP) and systolic(SAP) pressures were subsequently marked automaticallyfrom the Finometer and Doppler tracings and edited asnecessary. CBFVMEAN was calculated as a true average ofeach integrated waveform. We calculated a pulsatility indexas an estimate of cerebral vascular resistance by dividingmean arterial pressure by CBFVMEAN. Increases anddecreases in the pulsatility index are associated withcerebral-vessel constriction and dilation (5,18).

Statistical analysis. Data were analyzed withcommercial statistical software (SAS Institute, Cary, NC).We performed a repeated-measures analysis of variance toexplore the magnitude of differences among the means ofour dependent variables of interest. Differences betweentrials were probed further with Duncan_s post hoc meanseparation procedure. Exact P values were calculated toreflect the probability that the observed response rep-resented chance effects, given random sampling variability(9). Data are presented as means T SE unless specifiedotherwise.

RESULTS

Hyperventilation. End-tidal CO2 during baselinebefore exercise was 4.5 T 0.1%. Verbal encouragement forsubjects to breathe more deeply and quickly was asuccessful strategy to ensure close matching of end-tidalCO2 to experimental targets. End-tidal CO2 decreased to2.9 T 0.2% for the HV3% trial and decreased to 1.8 T 0.3%for the HV2% trial.

Responses during exercise. HR increased comparedwith baseline for all conditions, and HR was higher forHV2% compared with NOHV but not compared withHV3%. Arterial pressures increased compared with baseline

HYPERVENTILATION AND RESISTANCE EXERCISE Medicine & Science in Sports & Exercised 1303

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for all conditions. SAP was higher for NOHV but was notdifferent compared with HV3% and HV2%. DAP and MAPwere higher during exercise for NOHV compared with bothHV3% and HV2%. CBFVMEAN increased compared withbaseline during exercise with NOHV, and it decreasedcompared with both baseline and NOHV during HV3% andHV2%. The pulsatility index was unaffected compared withbaseline for NOHV, but it increased during both HV3% andHV2% compared with baseline and NOHV. End-tidal CO2

was reduced during exercise for both HV3% and HV2%compared with baseline and NOHV (Table 1). CBFVMEAN

and MAP responses to exercise are presented graphically inFigure 1.

Responses during standing. The effects of priorhyperventilation on CBFVMEAN and MAP during exerciseand standing are shown for one subject in Figure 2.Oscillations of both pressure and flow velocity are apparentduring each repetition, and the reductions in pressure andflow velocity are pronounced during standing.

HR during standing was 120 T 2.3 (NOHV), 122 T 2.2(HV3%), and 122 T 2.7 (HV2%) (P = 0.47). During recoveryafter exercise and standing, HR was 115 T 3.6 (NOHV),119 T 2.6 (HV3%), and 120 T 3.4 (HV2%) (P = 0.12). Themagnitude of arterial pressure and CBFVMEAN reductionsduring standing were similar between groups. MAP fell by97 T 12 mm Hg (NOHV), 97 T 12 mm Hg (HV3%), and96 T 12 mm Hg (HV2%) (P = 0.92). CBFVMEAN fell by40 T 3 cmIsj1 (NOHV), 41 T 4 cmIsj1 (HV3%), and 41 T5 cmIsj1 (HV2%) (P = 0.94). However, because hyper-ventilation decreased CBFVMEAN and because CBFVMEAN

increased during exercise for NOHV, CBFVMEAN was lowerat the beginning of standing after exercise with prior hyper-ventilation. Because of this, CBFVMEAN was lower whensubjects stood after HV3% and HV2% compared withNOHV. The absolute CBFVMEAN minimal values recordedduring standing are shown with MAP in Figure 3.

Symptoms of orthostatic instability. Feelings oflightheadedness, tunnel vision, or other feelings oforthostatic instability were greater (P = 0.02) for HV2%(2.1 T 0.31) than for HV3% (1.7 T 0.26) and NOHV (1.5 T0.16). Correlation analysis across all three exerciseconditions (N = 30 observations) revealed associationsamong symptoms of orthostatic instability and both the

magnitude of reduction during standing of MAP (r = 0.51;P = 0.003) and CBFVMEAN (r = 0.37; P = 0.039).According to the nomogram developed by Convertinoet al. (2), symptoms across all conditions were mild. Nosubjects reported serious presyncopal symptoms above a3.0 (moderate).

DISCUSSION

We studied the influence of hypocapnia induced withhyperventilation before lower-body resistance exercise oncerebral blood-flow velocity and symptoms of orthostaticinstability. The primary new findings from this study arethat 1) CBFVMEAN increases during leg-press exercisewithout prior hyperventilation but decreases with priorhyperventilation, 2) CBFVMEAN and arterial pressures arereduced more when subjects stand after leg-press exercisewith prior hyperventilation than without, and 3) symptomsof orthostatic instability are associated with the magnitudeof reductions in both MAP and CBFVMEAN during standingafter exercise. We conclude that voluntary hyperventilationbefore lower-body resistance exercise could contribute toorthostatic instability or even frank syncope by decreasingcerebral blood-flow velocity both during exercise and onstanding after exercise.

Responses during exercise. Arterial pressures onthe order of 450/380 mm Hg have been reported during

TABLE 1. Responses to leg-press resistive exercise.

Baseline NOHV HV3% HV2%

HR (bpm) 83 T 3.7 115 T 3.6* 119 T 2.7 121 T 3.4†SAP (mm Hg) 131 T 2.4 180 T 9.0* 177 T 8.2* 166 T 4.6*DAP (mm Hg) 72 T 4.7 100 T 3.9‡ 95 T 2.3* 91 T 4.7†MAP (mm Hg) 95 T 2.6 133 T 5.5‡ 129 T 3.8* 121 T 3.4*PI 1.5 T 0.1 1.8 T 0.2 2.4 T 0.2** 2.5 T 0.1**End-tidal CO2 (%) 4.5 T 0.1 4.4 T 0.2 3.7 T 0.1** 3.4 T 0.1**

Values are means T SE. NOHV, no prior hyperventilation; HV3%, end-tidal CO2 of 3%after hyperventilation; HV2%, end-tidal CO2 of 2% after hyperventilation; HR, heartrate; SAP, systolic arterial pressure; DAP, diastolic arterial pressure; MAP, mean arterialpressure; PI, pulsatility index. *P e 0.05 compared with baseline; ** P e 0.05compared with both baseline and NOHV; † P e 0.05 compared with baseline, NOHV,and HV3%; ‡ P e 0.05 compared with baseline, HV3%, and HV2%.

FIGURE 1—Mean cerebral blood-flow velocity (CBFV) and meanarterial pressure (MAP) are shown for subjects (N = 10) performingleg-press exercise with no prior hyperventilation (NOHV) and withprior hyperventilation to end-tidal CO2 levels of 3% (HV3%) and 2%(HV2%). * P e 0.05 compared with baseline; ** P e 0.05 comparedwith both baseline and NOHV.

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leg-press exercise (10). Such dramatic increases have beenattributed in part to weight lifters performing Valsalvamaneuvers (3). In the present study, we instructed oursubjects to avoid Valsalva straining, and we confirmed thatthey continued to breathe during lifting by monitoringbreath-by-breath end-tidal CO2. Arterial pressures increasedto 180/100 mm Hg with no hyperventilation, and to 177/95mm Hg (HV3%) and 166/91 mm Hg (HV2%) withhyperventilation. Although not as dramatic as pressuresreached during maximal lifting (10), increases of arterialpressure during leg-press exercise in the current study werehigher than the 140/50 mm Hg thought to define normalcerebral autoregulatory ranges (13).

Both arterial pressure and CBFVMEAN oscillated witheach repetition, as shown in Figure 2. Similar results havebeen reported by Pott et al. (14) during rowing and byEdwards et al. (4) during double-leg press. Cerebral vesselsautoregulate effectively with a response time of about 3–5s (16), which is probably slower than our subjectsperformed their repetitions. Figure 2 is representative ofall subjects with respect to the speed at which theycompleted their sets. Although we did not documentrepetition time, it seems from the subject depicted in Figure2 that each repetition averaged about 2 s. In the study byEdwards et al. (4), arterial pressure and flow-velocityoscillations driven by leg-press exercise were effectivelybuffered by autoregulatory mechanisms, such thatCBFVMEAN was unchanged compared with baseline. How-ever, MAP increased by about 17%, from 89 to 105 mm Hg

in the study by Edwards et al. (4); in the current study, itincreased by about 40%, from 95 to 133 mm Hg. Thisobservation may help to explain disparate results; an MAPof 133 mm Hg (and SAP and DAP of 180 and 100 mm Hg)moves the cardiovascular system beyond the cerebralautoregulatory range.

Hypocapnia induced by hyperventilation to either 3 or 2%end-tidal CO2 caused CBFVMEAN to decrease comparedwith both baseline and exercise with no prior hyper-ventilation (Fig. 1). Reduced CBFVMEAN occurred inconjunction with increases in cerebrovascular resistance(Table 1), as estimated from the pulsatility index (18).Arterial pressures were higher than at baseline duringhypocapnic exercise, but CBFVMEAN was lower than atbaseline. This observation supports the concept that reduc-tions in velocity are likely attributable to vasoconstrictionand are not simply reductions in cerebral perfusion pressure.The vasoactive effects of arterial CO2 are well established,with reductions causing cerebral-vessel constriction andreduced flow velocity (7). Cerebral blood-flow velocitydecreases by about 3.5% for every change in end-tidal CO2

of 1 mmHg (7). Although we recorded CO2 as a percentage,conversion to millimeters of mercury reveals that CO2

decreased from about 34 mm Hg (NOHV) to about 26mm Hg (HV2%), which should have resulted in a differencebetween the two conditions of about 30%. CBFVMEAN

decreased from 73 to 52 cmIsj1 (about 39%; data showngraphically in Figure 1), consistent with predictions.Although end-tidal CO2 is an imperfect predictor of arterial

FIGURE 2—Mean arterial pressure (MAP) and mean cerebral blood-flow velocity (CBFV) are shown for one subject during exercise with no priorhyperventilation (NOHV) and with prior hyperventilation to an end-tidal CO2 of 2% (HV2%). Arrows in the upper left panel denote when thesubject stood after exercise and then returned to the recumbent position (applicable to all panels).

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CO2, (17), it is reasonable to propose that reductions ofCBFVMEAN during lower-body resistance exercise afterhyperventilation are associated with reductions of arterialCO2. In conjunction with reduced CBFVMEAN, both SAPand DAP were lower during exercise for HV3% and HV2%compared with NOHV. Reduction of CO2 with hypocapniacauses vasoconstriction in cerebral arteries and vasodilationin systemic arteries (12). The vasodilatory effects of reducedCO2 in systemic arteries likely underlie our observation ofreduced DAP and MAP during exercise after hyperventila-tion compared with NOHV.

Responses during standing. Edwards et al. (4)have observed reductions of cerebral blood-flow velocity atthe conclusion of 10 repetitions of leg-press exercise. Noneof the subjects in their study experienced dizziness or othersymptoms related to presyncope, but they also remainedseated during recovery from exercise. Nevertheless,Edwards et al. (4) propose that the postexercise orthostaticinstability experienced by many weight trainers andcompetitive lifters (1) is probably related to reductions incerebral blood flow, increased cerebral vascular resistance,reductions in MAP, or some combination thereof. Weundertook the current study largely on the basis of the dataof Edwards et al. (4), and we found that when subjectsstood after exercise with prior hyperventilation, theirCBFVMEAN fell to levels below those seen during standingafter exercise without prior hyperventilation (Fig. 3). On the

basis of the representative response to our experimentalprotocol, as shown in Figure 2, it is apparent that standingafter heavy resistance exercise challenges both arterialpressure and cerebrovascular regulatory mechanismsextensively. Such dramatic reductions of pressure and flowvelocity likely do explain postexercise orthostatic instability,and the addition of hyperventilation before exerciseexacerbates the postexercise reduction of CBFVMEAN. Wealso would argue that hypocapnia exacerbates thepostexercise reductions of arterial pressure, becausedifferences between HV2% and NOHV deviated fromchance effects with a P value of 0.052 (Fig. 3).

We were unable to run a blinded experimental design,because subjects were required to hyperventilate volun-tarily. Although we did not reveal to our subjects thatwe expected them to experience a greater degree ofdizziness during standing after hyperventilation, wecannot discount the possibility that this outcome wasanticipated. Therefore, we cannot say with certainty thatsubjects_ knowledge that they were hyperventilatingbefore exercise did not influence their subjective ratingsof dizziness. With this limitation, subjects reportedfeeling more mild lightheadedness after HV2% comparedwith NOHV and HV3%. This observation is consistentwith the CBFVMEAN and arterial pressure reductionsduring standing after hyperventilation. Symptoms corre-lated with both the magnitude of reductions in CBFVMEAN

and MAP.

SUMMARY

At least one study has documented the voluntary hyper-ventilation performed by weight lifters as part of a routineto ‘‘psych up’’ for a maximal weight-lifting effort (1). Someathletes who incorporate preexercise hyperventilation expe-rience orthostatic instability or even frank syncope at theconclusion of exercise. We have shown that hypocapniareduces CBFVMEAN during lower-body resistance exerciseand exacerbates the fall in postexercise blood pressure andCBFVMEAN on standing. The reduced CBFVMEAN duringexercise seems to be independent of arterial pressurechanges, suggesting a direct effect of hypocapnia. Com-bined, our results suggest that the hypocapnia-induced fallsin arterial pressure and CBFVMEAN may lead to symptomsof postexercise syncope on standing after lower-bodyresistance exercise.

This study was supported by funding from the Department ofDefense, Medical Research and Materiel Command (W81XWH-05-P-1070) and by a Faculty Research Award from the University ofTexas at San Antonio, San Antonio, TX.

The authors have no professional relationships with companiesor manufacturers who would benefit from the results of the presentstudy. The results of the present study do not constitute endorse-ment of the product by the authors or by the American College ofSports Medicine.

FIGURE 3—The lowest mean cerebral blood-flow velocity (CBFV)and mean arterial pressure (MAP) recorded during standing afterexercise are shown for subjects (N = 10) after no hyperventilation(NOHV) and after prior hyperventilation to end-tidal levels of CO2 of3% (HV3%) and 2% (HV2%). * P e 0.05 compared with both NOHVand HV3%.

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