Fluid for Sport

Lucozade Sport Education Programme

Eimear ForbesSports Dietitian

(BSc. Hum Nut & Diet, Pg Cert Sports and Exercise Nutrition, MINDI, ISAK level 1

Anthropometrist),)

Objectives1. Outline effects of dehydration on health &

performance 2. Highlight issues around hydration in

endurance sports 3. Discuss what fluids to use & when (pre,

during and post exercise fluid choices)4. Provide a brief introduction to food for sport5. In workshops we will look at..

• Calculating fluid requirements & replacement• Monitoring hydration status

Running-effects on the body

For a person undertaking regular exercise, any fluid

deficit that is incurred during one exercise session can

potentially compromise the next session if adequate fluid

replacement does not occur.

Shirreffs SM, Armstrong LE, Cheuvront SN. 2005. Food nutrition and sports performance II

Fatigue During Prolonged Exercise

• Substrate (glycogen) depletion

• Temperature regulation/fluid balance

• Water becomes the most important performance-enhancing nutrient when exercise and heat stress are combined.

• In General dehydration is not good for achieving optimal athletic performance while exercising.

• Without fluid intake blood volume will drop, sweat rates will drop and body heat will rise.

• It is very difficult to consume enough fluids to match those lost during exercise

• Most athletes and coaches are aware that a reduction in the body’s water content impairs exercise performance.– What happens?

• Hydration status is determined by the balance of intake versus output• Water accounts for 50-70% of the body mass in most people.

– Females have less than males (they are lighter and have a higher proportion of body fat).

• An important route of water and electrolyte loss is through sweating.

Water/ Fluids

What are the functions of water• Maintain life (we can only survive a few days without it)• Gives structure and form to the body• Red blood cells carry oxygen in the plasma• Transports nutrients (glucose, electrolytes, iron)• Transports metabolic waste products and CO2• Transports hormones to target sites• Lubricates joints• Protects organs• Regulate body temperature by absorbing heat with only small

changes in temperature and dissipating heat• Influences blood pressure and cardiovascular function

Why is water important?• Fluid is essential to maintain hydration on a daily

basis• Body is ~ 55-65% water• Muscles made up ~ 70% water• Each g of Glycogen stores 3g of water• Water has important functions in the body

– Circulation of nutrients – Removal of waste products– Keep your body temperature stable– Protects organs (including brain – note combat sports)

– Influences blood pressure and cardiovascular function

What is Dehydration ?

• Dehydration occurs when water output exceeds water intake producing a deficit in body water

• Fluid loss arises from..– Sweating– Urination– Breathing & faecal losses smaller

• Sweat loss will depend on several factors• Considerable variability exists between

athletes of the same weight & sports

• Most athletes and coaches are aware that a reduction in the body’s water content impairs exercise performance

• Inadequate fluid during training and competition leads to: – ↓blood volume, ↓sweat rates ↑body heat &

underperformace

• It is often difficult to consume enough fluids to match those lost during exercise

• In combat sports dehydration is often used prior to ‘Making Weight’ (>2% not recommended)– Some degree of dehydration may be present at

competition but good post weigh-in recovery plans will minimize this

What do we need to consider?

Sweating

• Heat generated in exercise is transferred from the body core to the skin, where it vaporises the liquid sweat

• Evaporation of sweat usually accounts for 80% of heat loss during exercise

• Sweat rates of up to 1.5L per hour during moderate intensity exercise are not uncommon

Increased core temp sensed by

brain

Brain switches on

sweat mechanisms

Heat transferred

into atmosphere

Hot blood pumped to cooler skin

Sweating is effective in limiting the rise in body temperature during

exercise

Sweat rates of 1.5L/hr in

moderate intensity

exercise are common

What Can Happen Body

temperature

increases

Core temperatur

e rises

Not enough water for sweating

In hot humid conditionsSweat doesn’t

evaporate

If not replacing fluid Dehydration

What Can Go Wrong

Impaired performan

ce Heat stress

Circulatory collapse

Heat stroke/ hyperthermi

a

Body temperature

increases

Adverse Effects of DehydrationPhysiological effect

% bodyweight lost as sweat

Kg (lbs) for a 63.4 kg athlete (10 stone)

Impaired performance

2% 1.3 kg (2.8 lbs)

Capacity for muscular work declines

4% 2.5 kg (5.6 lbs)

Heat exhaustion 5% 3.2 kg (7.0 lbs)

Hallucinations 7% 4.5 kg (9.8 lbs)

Circulatory collapse and heat stroke

10% 6.4 kg (14.0 lbs)

How to Recognise Dehydration• Changes in body weight (pre and post training)

– Allows coaches and medical staff to see what athletes can usually lose in a training session or competition.

– Hydration plans can be individualised based on the results.

• Urine test– Colour is a practical way that athletes can use. – Specific gravity of urine measures the concentration urine. The more concentrated

the more dehydrated an athlete is.• A good field test for athletes to determine if they are prepared for training or

competition.• Results prior to training or competition allows you to make interventions to

improve hydration status before you start.

For every 1 kg (2.2 lbs) body weight lost in a training sesion, 1.5 litres of fluid must be replaced

Fluid requirements

• Athletes must be fully hydrated before they train or compete because the body cannot adapt to dehydration.

• Daily fluid requirements range between 2 – 4 L – Will vary to each individual and depends on..

weight, age, sex, sweat rate, environment, intensity & duration of activity

– 35mls per kg / BW adults + losses– 50mls per kg / BW <18 years + losses

Squash Player example• Training session ~ 1 hour training / match • Weighs 72kg before training & 71kg after training• 500mls drinks bottle before & 200mls remaining = drank 300ml

% Dehydration = weight difference x 100 = 1 x 100 = 1.4% weight before exercise 72

Total fluid loss = weight difference + fluids consumed = 1kg (1000ml) + 300ml = 1300mls

Fluid required = 1300mls x 1.5* = 1950mls – 300mls = 1650mls

*for every 1 kg body weight loss replace with 1.5l of fluids (150% Rule)

Stop for Task !

Task 2 – group work

• Divide into groups: 6x 6• Calculate in the 2 case examples

– TOTALS FLUIDS LOST – Fluid replacement required

Using a Pee Chart• Urine colour is a practical way that

athletes can use to assess adequate hydration

• Your target is to aim for the same colour as 1,2 or 3

• The more concentrated the urine the more dehydrated an athlete is.

• Specific Gravity of urine can be measured using a refractometer for more serious athletes

Monitoring hydration – Urine test

Monitoring Hydration Status

Purpose of Drinking

• Supply substrate (carbohydrate)

• Prevent dehydration

• Post-exercise dehydration

• Electrolyte replacement

• You can easily become dehydrated over successive days of training & competition if you fail to re-hydrate fully between workouts

• Check hydration status using Pee Charts• Watch out for..

– Sluggishness– General sense of fatigue– Headaches– Loss of appetite– Feeling excessively hot– Light headedness– Nausea

How to Recognise Dehydration

Importance of Hydration

• Thirst is not a good indicator• Different athletes will have different

fluid requirements: – For every 1kg lost in weight with exercise,

must replace by 1.5 Litre fluid. Indicates amount fluid needed in activity

• On average 150- 300mls fluid every 15 mins should combat dehydration

• Need to have fluid with electrolytes to avoid hyponatraemia

Avoiding Dehydration General Guidelines

• Accustom your body to increased fluid intake during training and competition

• Practise all new strategies in training or minor events

• Wear appropriate clothing that allows heat transfer

Avoiding Dehydration Pre-Training/Competing

• Begin exercise when fully hydrated• Drink sports drink or water prior to

exercising until your urine is clear• Allow some time to get rid of

excess urine• In sports lasting < 30 mins water is

still the recommended fluid replacement during exercise (ACSM 2007)

Avoiding Dehydration During Training/Competition

• 150ml / 15mins endurance sport, 30-60g CHO per hour

• Therefore if no food taken when exercising use 6-8% CHO drink ( ie isotonic drink) to provide fuel and fluid

• Don’t use thirst as an indicator of need for fluid

Avoiding DehydrationAfter Exercising

• Drink 1.5 L for every 1 kg weight lost• Choose a drink designed to rehydrate most

effectively• The drink should contain:

– Relatively high concentration of electrolytes (especially sodium around 50 mMol/l) to maximize fluid retention

– 6-8% carbohydrate for optimal fluid/energy recovery

– 2-3% carbohydrate for optimal rehydration

General tips for Fluid Replacement

• Drink before you get thirsty• Pre-hydrate – drink before exercise• Non-carbonated drinks – are tolerated better

• Caffeine free – drinks high in caffeine can cause dehydration

• <6-8% carbohydrate solution for fast absorption• Temperature: 8-12

oC – cooler drinks leave stomach sooner

• Palatability. Pick a drink you like• Individual variation-practice prior to competition• In Sports lasting < 30mins water is still a recommended

fluid to use for hydration during & after activity

Sports Drink vs. Water

Sports Drink Water

Fast energy (calories, carbs)

YES NO

Avoid fatigue YES NO

Electrolytes YES NO

Taste YES ??

Fluid YES YES

Restrict isotonic sports drinks if you are:

• On special diets (e.g. carbohydrate restriction)

• Attempting to lose weight• Making weight for a specific sport

Dental Health – remember your teeth!

• Sports drinks are acidic which can breakdown tooth enamel

• They also contain carbohydrate which can increase dental caries

•Brush and floss your teeth regularly•Ensure regular dental check-ups•Chew sugar free gum•Use a squeeze bottle or drink from a straw.•Drinks should be slightly chilled.•Rinse mouth out with water after eating and drinking.

Sports Drink Type En kcal100mls

Cho g100mls

Na mg100mls

Other Nutrients & comments

Lucozade Sport

Isotonic 28 6.4 50 Bvits

Energize Sport Isotonic 27 6.2 10 BVits, Ca, Mg & KSugars & sweetners

Powerade Isotonic 24 5.6 50 Bvits & K

Provon revive – made up 500mls

Recovery 59 11g 40.4 BCAA4g, Ca, Mg, K& Vit CGlutamine….

Hydrate BPM Energy

Hypertonic

64 15.3 0 Bvits, Vit C & ECarbonated

Lucozade original

Hypertonic

70 17.2 trace Caffeine (0.012%)Carbonated

Lucozade Alert

Hypertonic

60 14.7 trace 30mg caffiene/100mls= 75mg/250ml bottle

Lucozade Hydro Active

Hypotonic 10 2 trace Bvits, CaSugars & sweetners

Home Made Sports Drinks

• Using Fruit Juice– 500mls fruit juice– 500mls water (cooled boiled water)– 1g salt

• Using diluted squashed– 200ml fruit squash– 800ml water (cooled boiled water)– 1g salt

• Using glucose / carbohydrate powders– 40-80g sugar/glucose powder– 1000mls water (cooled boiled water)– 1g salt

Practice Makes Perfect……

• Practice hydration and food techniques in training

• Nothing new on day of event• Fluid and carbohydrate pre, during

and post event are vital for optimum performance

If you want to avoid dehydration and

enhance performance…consume plenty of fluids before, during and after

exercise.

Thank YouFor more information, log on to these websites:• Irish Nutrition and Dietetic Institute

(www.indi.ie) – find a dietitian, sports nutrition info

• Coaching Ireland website (http://www.coachingireland.com)

• Lucozade Sport Science and Nutrition centre (http://www.lucozadesport.com/lucozade/wwwroot/index.html)

Summary Table: Nutrition and Hydration Principles in Endurance Sports

Pre Race During Race Post Race

Carbohydrate 200-300g 2-4hrs pre event

30-60g/hr 1g/kg up to 1hrs post exercise with protein source immediately post exercise

Fluid 400 – 600mls up to 2hrs pre exercise

400mls -800mls / hr activity or approx 150ml/hr activity

Per 1kg weight loss post exercise replace 1.5 L

This applies to event of approx 1hr or more, plans must be individualised to each person and sport

What are the key nutritional issues for performance?

• Adequate appropriate fuel or energy (calories)

• Adequate fluid• Timing especially for recovery• Good balance• Habit• Preferences

Adequate Energy• There are four components in food and drinks that

are capable of producing energy– Fat (essential nutrient, little risk of depleting stores)– Alcohol (contributes to increase in fat stores, negative

impact on recovery and hydration strategies)– Protein (growth and repair, significant structural part of

muscle)– Carbohydrates (sugars and starches) (most important

nutrient for exercising muscle, stores last max 70mins in exercise)

• The exercise intensity will determine the type of fuel that is used.

• Vitamins and Minerals essential

Energy Stores: Where Is Fuel Stored?

• In the blood as glucose

• In the liver and muscles as glycogen

• In adipose tissue as fat (just below the skin)

• Muscle will be broken down to access protein if it is used as an energy source (if carbohydrates are not present).

Energy Stores: Where Is Fuel Stored?

If don’t fuel well…Consequences?

• Early Fatigue• Poor Recovery• Lose weight• Difficulty building muscle

• …………….Impaired Performance

Nutritional Requirements in Sport

Carbohydrates

Individual quantities but an intake based on individual weight is best (6-10g /kg/day minimum).

Protein Requirements will be different on different training daysStrength training: HIGHER PROTEIN REQUIREMENTS >2g / kg / dayEndurance or aerobic training: FOCUS ON CARBOHYDRATES AND REDUCED PROTEIN 1.2-1.7g / kg / day

Fats Usually 15-35% of your daily calorie intake (50-90 g/day). Try to chose fats that are good sources (oily fish, nuts, leans cuts of meat, poly or mono unsaturated spreads)

Energy Will depend on the individual but some athletes who need to gain weight may need in excess of 4000 calories per day. Need to work on a day-by-day basis rather than taking an average.

Carbohydrates• Stored in body as glycogen in liver and muscle = limited

stores• Inadequate intake = incomplete glycogen stores• Effects: early fatigue, poor recovery, weight loss, under

performanceLevel of training Recommended

Intake

Low intensity / <60-90mins 5-7g/kg

Exercise 90-120mins 7-10g/kg

V.Heavy / extreme exercise programme 10-12g/kg

Carbohydrate loading for endurance exercise

7-10g/kg

Increasing Carbohydrate Stores

• Carbohydrate at each meal: cereal, bread, pasta, rice, potatoes, fruit

• Fruit to breakfast cereal, thicker slices bread, potato in soups / salads

• Carbohydrate snacks: Fruit, low fat yoghurt, smoothie, cereal bar, dried fruit

• Use sparingly the less nutritious sources of carbs: fizzy drinks, desserts, sweets, biscuits, gels

Carbohydrate Sources

S low re lea se to b loo ds tre am

Com plexS ta ch es , r ice , p a sta , b rea d , ce re a ls

F a st re le ase to b lo od s tre am

Sim pleS u ga rs, ho n ey , g lu co se , fru i ts

What about Protein???• Despite the research available on

carbohydrates athletes often believe that protein is the most important nutrient to achieve athletic success.

• Majority athletes require increased protein intake

• Can be met from the increased food intake as result of overall extra energy and carbohydrate requirement

• Carbohydrate consumed with small amount protein (approx 11g) post exercise will promote recovery and regeneration processes

On the day- pre match

• When to eat:– Do Not skip breakfast– Nerves may slow down digestion– Aim for 2-4 hours pre event meal ( 1-2 hrs pre event snack)

• Low GI, low fat, low protein

• Low or moderate in fibre (high fibre may cause abdominal discomfort)

• Not too spicy

• Enjoyable and familiar foods

Pre-Exercise NutritionExamples of suitable 3-4 hours pre-

event meals include:• Toast with baked beans and

scrambled eggs• Cereal and milk • Baked potatoes with bolognaise

sauce• Pasta or rice and tomato sauce• Sandwiches and soup

– Followed by fruit salad and / or ice cream

Examples of suitable 1-2 hours pre-event foods include:

• Sports drinks**• Fruit smoothies• Milkshakes• Fruit (fresh or tinned)• Cereal bars**• Sweets, sports gels and bars **

** Good teeth cleaning is appropriate as these have large amounts of refined carbohydrates which can cause dental decay.

Pre- Exercise Nutrition

On the day: during the Race / Match

• Guideline for endurance: 30-60g CHO/ hr activity, 150mls / 15 mins

• Fluids: Isotonic drinks are most convenient way of delivering carbohydrate, fluid and electrolytes simultaneously.

• Water can be used if consuming food but may need electrolyte replacement

• Foods: Quick release carbohydrates /convenient foods – sweets, jaffa cakes, cereals bars, oranges, sports gels.

Nutritional recovery strategies between or after exercise

• Protein and carbohydrates together is thought to increase the recovery time.

• Intake of these foods needs to be as soon as possible after training or competition to maximise “the window of opportunity”.

• Personal plans that have been practiced are crucial.

Glycogen Replacement After Exercise

(Costill 1985)

Recovery Ideas

• Skimmed milk with flavouring• Milkshake • Drinkable yoghurts• Smoothie• Recovery sports drinks

The amount needed will depend on your weight and requirements

Refuelling IdeasSuggestions (these foods are also sources of other nutrients):

•1½ cups cornflakes with milk (60g carbs)• 2 slices of toast with jam (50g carbs)•2 medium bananas (50g carbs)•1 Lucozade Carbo Gel (30g carbs)•1 bottle (500mls) sports drink (32g carbs).• 2 pancakes with banana (40g carbs)• Fruit smoothie with yoghurt (varies)

Kit Bag Ideas• High Carbohydrate Snacks:

– Sports Drinks (eg Lucozade, Powerade, Club Energise, or a home made solution)

– Fruit Juice or Fruit Squash– Bread Roll with Jam / Honey– Dried Fruit / Banana– Breakfast Bar / Cereal Bar – Jellies / Pastilles / Marshmallows

• High Carbohydrate and High Protein Snacks– Ham / Tuna / Turkey Sandwich– Flavoured Milk– Yoghurt Drink– Fruit Smoothie: Fruit Juice, milk, yogurt– Protein Enriched Sports Drink: eg Lucozade Recovery– Sports Drink Enriched with Skimmed Milk Powder– Popcorn

Additional Consideration• Overweight / Avoid Excess Weight Gain

– Low Fat milk, yoghurts, cheese, spreads, mayonnaise

– Avoid adding extra butter, oils, cheese (eg to pasta), mayonnaise, milk to foods

– Cut fat off meat, skin off chicken, avoid frying.– Limit treats (chocolate, crisps, takeaways– Diet drinks except when active / training

THE FOOD PYRAMID

6+ servings

5 servings

3 servings

2 servings

Very small amounts

Others

Meat, Fish & Alternatives

Milk, Cheese &

Yogurt

Fruit & Vegetables

Breads, Cereals &

Potatoes

Fluid6-8 cups

Practice Makes Perfect……

• Practice hydration and food techniques in training

• Nothing new on day of event• Fluid and carbohydrate pre, during

and post event are vital for optimum performance