Gross Motor Skills Skills that involve the movement of large body parts or the whole body Cardiac...
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Transcript of Gross Motor Skills Skills that involve the movement of large body parts or the whole body Cardiac...
Gross Motor Skills
Skills that involve the movement of large body parts or the whole body
Cardiac output
The volume of blood pumped by the left ventricle in one minute
Stroke Volume
The volume of blood pumped by the left ventricle in one contraction
Thermoregulation
The ability of an organism to keep its body temperature within certain boundaries
Vascular Shunting
The process of directing blood to where it is most needed
Vasoconstriction
Narrowing of the blood vessels
Vasodilatation
Widening of the blood vessels
Hypoxia
A shortage of oxygen in the body
Venous return
The flow of blood back to the right atrium of the heart
Ventilation Rate
The rate at which gas enters or leaves the lung
Sympathetic nervous system
The link between the cardiac acceleratory system and the heart that results in an increase in heart rate
Tachycardia
Abnormally rapid heartbeat (over 100 beats per minute)
Hydrated
Combined chemically with water
Osmolality
A measure of the number of particles in a solution.
Hypothermia
A condition in which the body temperature drops below that required for normal metabolism and bodily functions
Hyperthermia
An acute condition that occurs when the body produces or absorbs more heat than it can dissipate
Why?
• Prepare the body physiologically and psychologically for performance
• Improve performance
• Reduce the risk of injury
Stage 1: Initial Preparation
• Gross Motor Skills and Pulse Raiser
• Introduce stress in a gradual and controlled manner
• Raise core body temperature
• Raise Muscle temperature
• Achieved by some for of cardiovascular exercise
Stage 2: Injury Prevention
• mobility exercises
• Increase localised muscle elasticity
• Stretches
Stage 3: Skill Practise
• Involves skill related component
• Neuromuscular mechanisms for the activity are worked
• Example shooting in netball
Stage 4: Sport-Specific
• Often combined with Skill Practise
• Practise specific skills and exertions similarly to how they will be experienced in match situations
Increase in heart rate which leads to vasodilatation of some blood vessels
Increase in stroke volume which leads to vasoconstriction of some blood vessels
Increase in cardiac output which leads to vascular shunting Increase in venous return which
causes thermoregulation to begin
Increase in localised and core heat generation which causes localised muscular metabolism to speed up
Ventilation rate increases which causes dilation of capillaries
Carbon Dioxide build up
Production of lactic acid, synovial fluid and adrenaline
Increase in the speed of nerve impulses
Increase in muscle elasticity
Used to increase the elasticity of muscle and connective tissue to reduce the risk of injury.
Static Stretching
• lack of movement
• Stretch a muscle and hold position for up to 30 seconds, relax and repeat
• least sports specific
Dynamic Stretching
• Controlled movements taking the joint through its full range of movement
• More sports specific than static
• Muscle joint must be warm
• Controlled leg swings
Passive Stretching
• Assume position and hold it with some other part of your body, with a partner or apparatus
• E.g. partner lifts extended leg and holds it in place
Ballistic Stretching
• Like dynamic but uses bouncing or momentum to help forcibly stretch the muscle
• Bouncing action means increasing the risk of injury & increasing potential for Delayed-onset muscle soreness
• Unlikely to allow muscles to adjust to and relax in the stretch position. Could cause them to tighten up
• Very sports specific
Proprioceptive Neuromuscular facilitation (PNF)
• Advanced form of flexibility training
• Involves passive stretching followed by isometric contractions of muscle group being targeted
Active Stretching
• You actively stretch the muscle yourself
• E.g. sit with legs outstretched and move body towards your legs yourself
Adenosine Phosphate Phosphate Phosphate
ATPaseEnergy
•ADP
• Phosphate
Phospho creatine
CreatineKinase
Phospho creatine Energy
Energy Phosphate ADP ATP
2-3 Seconds
8-10 Seconds
• ATPase breaks up the ATP to form ADP, Phosphate and Energy
• Phosphocreatine is broken down by Creatine Kinase which produces energy. This energy is then used to reform an ATP molecule by binding ADP with a phosphate
ATP= Exothermic reactionPC= Endothermic Reaction
Coupled Reaction
Occurs in the sarcoplasm
of the muscle
Controlling Enzymes
• ATPase
• Phosphocreatine
By Products & effects
• Creatine but has no effects and will eventually rejoin Phosphate to form phosphocreatine again
Recovery Process
• Lactic Acid System
Practical Application
• Shot Putt
• Shooting in netball
• 100m for an elite athlete
ANAEROBIC
One Glucose Molecule
PFK
Two molecules oflactic acid
Two molecules of pyruvic acid
Energy 2ATP
Lactate dehydrogenase
LDH
Can last for 2-3 minutes
Type of Reaction
• Exothermic
•Anaerobic Reaction
Chemical/ Food Fuel
• Glucose
ANAEROBIC
Reaction Site
• Sarcoplasm of the muscle
Controlling Enzymes
• PFK which turns glucose into pyruvic acid
• LDH which turns pyruvic acid into lactic acid
By products and their effects
• Lactic acid which can cause cramps which will then cause the athlete to stop competing
Practical Application
• 800m
• Following or defending a player on the ball in football
Because it is not at full intensity and will last longer than 15 seconds
Medium Intensity
Recovery Process
• Aerobic System
• Active cool down
Aerobic Glycolysis:
Glycogen Glucose Pyruvic AcidPFK
2ATP
Krebs Cycle:
Pyruvic AcidCoenzyme A Oxalocetic
AcidAcetyl CoA
Citric Acid
Various Chemical Reactions = Carbon Dioxide, Hydrogen and2ATP
Electron Transport Chain
FADNADHydrogenWater
34 ATP
Total of 36 ATP
Type of Reaction
• Aerobic Reaction
Chemical/ Food Fuel
• Glucose
Reaction Site
• Sarcoplasm of muscle
• Mitochondria
Controlling Enzymes
• PFK
• CoenzymeA
• NAD
• FAD
By Products and their effects
• Carbon Dioxide which increases the athletes respiration rate
• Water which induces sweating and increases urine output
Practical Application
• Marathon
• Football to last the full duration of the match
Recovery Process
• Active Cool Down
• Stop Exercise
Low Intensity but High to very high duration
After about 3 minutes
Energy Source
Main Functions
Used as energy fuel when:
Carbohydrates
High intensity energy
Intensity of exercise is at a level that cannot be sustained through
metabolism of fats in the aerobic system
Fats Low intensity fuel
Insulation
Intensity of exercise is at a medium to low level and energy requirements can be met through metabolism of fats in the aerobic energy system
Proteins Muscle tissue growth
Muscle tissue repairEnergy
The athlete has eaten very low carbohydrate diet or is experiencing a famine or towards the end of an ultra-
distance event
• Glucose is the basic usable form of carbohydrate in the body.
• Can be used directly by the cell for energy, stored as glycogen in the muscle and liver or converted to fat
• The function of the liver is to convert glycogen into glucose when it is needed for energy production
Monosaccharides Glucose, Fructose and
galactose
Fruit
Disaccharides Sucrose and maltose
Sweets
Polysaccharides Glycogen and starch
Bread
Anaerobic: 55-60%
Aerobic: 60-70%
Fats are present in the body mainly as triglycerides, fatty acids and cholesterol
Saturated Fats
• Has its carbon atoms saturated with hydrogen atoms
• Consumption of large amounts can lead to high blood cholesterol levels and coronary heart disease.
• Obtained from animal fats such as pork, beef and lamb
Unsaturated Fats
• Does not have their carbon atoms saturated with hydrogen atoms
• Liquid state at room temperature
• Found in vegetable oils
Anaerobic: 10-20%
Aerobic: 20-30%
• The basic structural units of proteins are amino acids.
• Used also to create the essential enzymes within the body
• Foods that are richest in essential amino acids are animals proteins and milk
• Proteins in the body are part of either tissue structures or part of the metabolic system such as transport, hormone or enzyme systems
• We Do not have a protein store
• Role of providing energy has become increasingly clear that protein metabolism is increased during endurance exercise
Cereal, Cheese, eggs, fish, lean meat and liver
Anaerobic: 10-15%
Aerobic: 15-20%
Ensure that adequate fuel is consumed to facilitate the intensity and duration of training
Ensure that fuel stores are full before a performance
Ensure that fuel stores are supplemented during the activity as required
Fuel stores are replenished immediately after the end of exercise
Supplementation (with vitamins) is undertaken to ensure the body can utilise the nutrients required
Hydration is maintained both before and during performance
Adequate protein is consumed to enable the necessary growth and repair of muscle tissue
Expenditure must equal intake
Carbohydrate Loading
A legal method of attempting to boost the amount of glycogen in the body before a competition or event
• Aims to super-charge glycogen stores for long duration activity such as a marathon
• Achieved by using an intensive training sessions that deplete muscle glycogen stores 7 days prior to competition
• For the next 3 days that athlete mainly eats fats and proteins to deprive the muscle of carbs. This has the effect of increasing the activity of glycogen synthase. During this period training is tapered
• In the final 3-4 days prior to the event the athlete switches to a carb rich diet and increases fluid intake. Because glycogen synthase has been increased, carb intake now results in increased muscle glycogen storage
The overall effect is for performance times to improve significantly
Disadvantages
• Increase in body weight since more water is needed to store the glycogen
• During depletion, athletes feel week, depressed and irritable
Competition Day
The best time to eat is 2-3 hours prior to the event and meals should be of low volume, contain plenty of carbohydrates and fluids. This is because liver glycogen stores need topping up even in a well nourished athlete
During short events the athlete will need to eat nothing. For long duration events such as the marathon, the athlete will need to eat little but with high carb content for example jelly babies
British Olympic athletes Linford Christie, Sally Gunnell and many of the rowing squad all used creatine in their preparation for the 1992 Olympics
• Creatine is effective in treating many muscular, neuromuscular and neurodegenerative diseases
• Ingesting creating can increase the level of phosphocreatine in the muscles by up to 20%
• Has no significant effect on aerobic endurance though it will increase power in anaerobic exercise
• Often taken by those wanting to gain muscle mass
• Powder or tablets are the most popular methods
• Not considered doping and so is legal
• In France the supplement is banned
Rapid weight gains have been found but the reason for this is unclear. Some argue that it’s due to water retention others that it’s the gain in muscle mass.
With water loss comes the additional problem of electrolyte loss. The most important being sodium.
• Water alone will not be able to rehydrate the performer
Electrolytes
Substances containing free ions. They play a vital role in homeostasis in the body helping to regulate and manage the water and fluid levels
• Essential minerals
• Control osmosis of water between body compartments
• Help to maintain the acid base balance required for normal cellular activities
Hydrated
Combined chemically with water
Body weight lost as
sweat (%)
Physiological effect Performance effect
1 Loss of 5%
2 Impaired performance Loss of 10%
4 Capacity for muscular work declines
Loss of 25%
5 Heat exhaustion Potential failure to compete
7 Hallucinations Potentially fatal
10 Circulatory collapse and heat stroke
Potentially Fatal
Plain Water
•Causes bloating and suppresses thirst.
• Stimulates urine output
• Contains no carbohydrate or electrolytes
Electrolytes in a drink
• reduce urine output
• enable the fluid to empty quickly from the stomach
• promote absorption from the intestine
•Encourage fluid retention
Two main factors affect the speed at which fluid from a drink gets into the body:
• the speed at which it is emptied from the stomach
• the rate at which it is absorbed through the walls of the small intestine
Ensures that you do not lose more than 2% of your pre race weight
How
• Record your body weight immediately before and after a number of training sessions along with details of distance/duration, clothing and weather conditions
• Add the amount of fluid taken during the session to the amount of weight lost 1kg is approx 1l of fluid
• After a few weeks patterns should emerge and you can calculate your sweat rate per hour
• Once you know what your sweat losses are likely to be in a given set of environmental conditions, you can plan your drinking strategy for specific events
• Blood will have a typical osmotic value of 5% glucose concentration.
• A glucose solution greater than this will empty very slowly into the stomach
• A solution lower will enter the blood stream much quicker but this means taking in a lot more liquid
• In order to get carbs into the body quickly a low concentration is required but a lot of volume is necessary because of the low concentration
• Many sports nutrition companies use glucose polymers which are far less osmotically active. Some drinks can be 50% glucose concentration but still be isotonic. This allows more glucose to be consumed in a smaller volume of drink
• Drinks with an osmolality of 270-330mOsm per kg are said to be in balance with the body’s fluid and are called Isotonic
• Hypotonic fluids have fewer particles than the blood.
• Hypertonic fluids have more particles than the blood
Type Content Glucose Content (volume)
Isotonic Fluid, electrolytes and
6-8% carbohydrate
Similar to blood or the body
Hypotonic Fluids, electrolytes and
a low level of carbohydrate
Less than blood or the body
Hypertonic High level of carbohydrate
Greater than blood/body
Humid Heat
• Humidity of the surrounding air prevents the evaporation of perspiration to some extent
• Over heating may result
Dry Heat (Desert Conditions)
• Better able to lose heat through sweating
• the atmosphere absorbs moisture better
• Danger becomes dehydration as the athlete may not realise how much they are sweating as it will evaporate quickly from the skin
14 Days to fully acclimatise
Athletes with a higher VO2 max will acclimatise quicker
Benefits
Improved tolerance of heat which allows athletes to perform as they would in normal conditions without incurring heat related illnesses
Adaptations
• Expanded plasma volume
• Improved control of cardiovascular function
•Reduced resting heart rate
• Onset of sweating earlier and so the body can stay cooler
• Increased Sweat rate
• The body’s ability to reduce the amount of sodium chloride lost during sweating (Losses decrease between day 3 and 9 but revert back once acclimatised)
Adaptations may disappear after only a few
weeks of inactivity18-28 days
Heat cramps
Usually in the muscles of the legs, arms and abdomen after several hours of strenuous activity, in individuals who have lost a large volume of sweat, drunk a large volume of hypotonic fluid and who have excreted a small volume of urine. Sodium depletion probably causes heat cramps
Heat Syncope
• AKA fainting
• Most commonly first 3-5 days of heat exposure
•Due to vascular shunting of blood to skin in order to cool down and the consequent reduction in venous return and drop in cardiac output in turn leading to a drop in blood pressure
Heat Exhaustion
• Most commonly diagnosed
• Symptoms vague but can include headaches, dizziness, hyperventilation, vomiting, syncope, head cramps, tachycardia
• Defined as inability to continue exercise in a hot environment
Effects of Altitude
• Partial Pressure of Oxygen is lower
• Reduction in driving pressure for oxygen transport
• Fall in VO2 max
Training Method
Result
Live High Train High
LHTH
Maximum exposure to altitude but evidence of a positive effect at sea
level is controversial
Live Low Train High
LLTH
Exercise in a low oxygen environment but rest in normal
conditions. Some positive findings but still no real evidence of any
difference to competitive performance at sea level. Training intensity is reduce so some may loose fitness with this method
Live High Train Low
LHTL
Live at altitude for more than 12 hrs per day over 3 weeks whilst
maintaining training intensity at or near sea level. Improvements in sea level performance have been shown
in events lasting 8-20 minutes
Increases in Erythropoietin (EPO) levels. However after prolonged exposure they return to normal levels
Increased VO2 Max
Increased Red blood cell and haemoglobin concentration. (known as polycythaemia) It may take 3 months for the body to have an optimum level of red blood cells.
Hyperventilation (increased pulmonary ventilation)
Increased muscle and tissue capillarisation
Increased myoglobin concentration. This enables tissue to extract more O2 and remove more CO2
Increased mitochondrial density. Enables greater and faster production of ATP