Presentation on theme: "England Athletics Workshop NUTRITION FOR PERFORMANCE By Mistrelle Baker 23 February 2010."— Presentation transcript:
England Athletics Workshop NUTRITION FOR PERFORMANCE By Mistrelle Baker 23 February 2010
Nutrition for Optimal Health and Performance Are you eating the right foods to be the best?!!
GENERAL NUTRITION Key Points : 1.Healthy food 2.Nutrition for training 3.Recovery and performance
NUTRITION FOR HEALTH
Is Your Diet Healthy and Balanced? Carbohydrate - Is it a large proportion of your intake? Fat - Is it too high? Fat - Are you avoiding animal fat? Fibre - Do you include brown or wholemeal starchy foods? - Do you eat five fruit or vegetable portions a day? Is your diet varied?
BALANCED EATING 1. Bread, cereals, potatoes, rice 55-65% of daily food. 2. Fruit & vegetables Eat 5 portions every day (include variety) 3,4.Meat & fish / dairy products 10-15% of daily food -choose low fat versions 5. Fats and sugars 20-25% of daily food - unsaturated fat rather than saturated fat
1. BREAD, CEREALS, POTATOES, RICE Complex carbohydrates Should form basis for meals Combine different forms for each meal Replace fuel stores Optimise performance
2. FRUIT & VEGETABLES Performance & recovery Vitamins & minerals Iron, potassium, calcium, chromium, niacin, phosphorous, biotin, zinc, vits A, C, E, B1, B2, B6, B12.
3. MEAT, FISH & ALTERNATIVES Meat & meat products, poultry, fish & fish products, offal, eggs, beans & lentils, nuts, textured veg. Performance & recovery Protein Bone, skin, muscles, hormones, enzymes, haemoglobin and platelets Muscle growth, repair and maintenance
4. MILK & DAIRY FOODS Performance & recovery Fat and protein Energy source, bone & teeth strength, muscle & tissue repair
5. FATTY & SUGARY FOODS Use fats sparingly! Sweets may be used to aid recovery!
NUTRITION FOR PERRFORMANCE
How can food and drink affect performance? 1. Provide and replace fuel stores 2. Repair and strengthen damaged muscle tissue 3. Replace fluid losses
Daily Calorie Intake ENERGY BALANCE Food Intake and Energy Used Generally… Male young athletes : 3000kcal Female young athletes : 2500kcal HOW DO YOU KNOW HOW MUCH ENERGY YOU USE? Every day at rest Exercise training and competition
Fuel for Sport 1. High Intensity Exercise: (eg field events, sprints) Fat Carbohydrate Carbohydrate is the only provider of energy for high intensity activities
Fuel for Sport 2. Medium Intensity Exercise (eg middle distance running) Fat Carbohydrate Carbohydrate is the main provider of energy during medium intensity activities
Fuel for Sport 3. Low intensity Exercise: (eg long distance running/cycling) Fat Carbohydrate As duration continues the contribution of fat increases OHT 5
The effect of different amounts of carbohydrates on muscle glycogen levels after exercise (Costill et al. 1981) High CHO diet Muscle Glycogen Levels Insufficient CHO in diet Time 0 24h 48h 72h
Practical Recommendations for Carbohydrate Intake Considerations Type Amount Rate Timing
Daily Requirements g 55-65% total intake Complex () and simple CHO () Limited stores of glycogen ( kcal) Dependent on: Exercise intensity Exercise duration Diet Body size Fitness status
Type 1. Glucose, sucrose, maltodextrins (6-8% solution) 2. Liquid versus solid 3. Low versus high glycaemic index foods
Practical Recommendation (Type) Within first 6h, high glycaemic index foods or simple carbohydrates (glucose, sucrose, maltodextrin) provide the best glycogen replacement Provide a CHO-replacement fluid containing 70-90g of CHO immediately after exercise if the athlete is unable to consume solid food
Amount Before During exercise After exercise
Practical Recommendation (Amount) A. BEFORE Carbohydrate loading / glycogen supercompensation Bergstrom et al. (1967) : Classical 3d : Low-CHO diet (<10%) & glycogen depleting exercise 3d : High-CHO diet (>90%) & low activity Day seven = Competition / race
Adverse effects Injury Irritability Decreased ability to train Dizziness Fluid loss G-I disturbance Weight gain
Practical Recommendation (Amount) B. DURING Replace fluid / sweat losses Temperature Humidity Wind velocity Duration / type / intensity of event Up to 2 litres per hour Sip every 15 minutes
Practical Recommendation (Amount) C. AFTER Dependent upon type of recovery Active Passive rest Muscle damage / soreness Time-course of recovery See Rate for recommendations
Rate Factors determining rate of glycogen synthesis Degree of muscle glycogen depletion Degree of insulin activation of glycogen synthase CHO content of post-exercise diet
Practical Recommendations (Rate) Frequent feedings over first 4-h 0.4g maltodextrin, every 15mins Highest level of glycogen resynthesis
Timing A. Immediately post-exercise B. First 2 hours post-exercise C. Immediate versus Delayed intake D. 4 hours post-exercise
Practical Recommendation (Timing) g carbohydrate within the first hour after exercise, depending on body size. Combine this carbohydrate with some dietary protein if possible. Over 24h, feed 6-8g/kg (f), 8-10g/kg (m)
Inappropriate CHO Intake Excess (simple) Nutritional deficiencies Obesity High cholesterol Dental problems Gastrointestinal irritation Deficiency (complex) Tissue wasting (extreme) Homeostatic imbalance Severe fatigue Lack of alertness
Identify the purpose of fluid intake in the diet Summarise the difference between pre-, during and post-exercise fluid intake Assess problems associated with excess or deficient fluid intake FLUID INTAKE
Water ~60% of total body weight Intracellular and extracellular Functions Transport medium Structural part of body tissues A lubricant Component of chemical reactions
Water and Exercise Optimal fluid balance depends on: Environment Type, intensity, duration of exercise Personal palatability Content of fluid intake Rates of gastric emptying Intestinal absorption
Dehydration Decrease in total body water Rapid fatigue Performance reduction
Hypohydration Aesthetic appearance / weight category sports Athletes voluntarily dehydrate Negative affects upon performance Short-term adverse health effects
Hyponatraemia During exercise Low plasma sodium concentrations Consumption of excess water Sodium intake is low / losses are high Fatigue Nausea
Electrolytes Function Maintain distribution of water within and outside cells Balance of water and electrolytes is maintained by endocrine and neurological mechanisms Losses Sweat Prolonged exercise Hot / humid environment
Practical Recommendations Isotonic drinks contain the same amount of particles as blood do not prevent the absorption of fluid contain small but useful amounts of energy (5- 8% carbohydrate solution) contain a small amount of sodium (salt) to assist the absorption of fluid can be drunk before, during or after exercise without problem.
Hypotonic drinks contain fewer particles than blood do not prevent the absorption of fluid contain very small amount of energy – not sufficient in most cases to be useful can be drunk before, during or after exercise but will not contribute sufficient energy to be useful in most cases
Hypertonic drinks contain more particles than blood prevent the absorption of fluid contain high levels of energy should not be drunk during exercise generally as can result in dehydration.
Practical Recommendations BEFORE 2 h : 500ml fluid Glucose / water solution with salts DURING ml.h. -1 Maintain plasma volume Control electrolyte balance AFTER Replace water and electrolyte losses Solid and fluid intake Continue until urine is pale yellow
Recipes for home-made sports drinks 1. 60g of glucose dissolved in 1 L of water or diluted sugar free squash. Add 1/5 th of tsp of salt g glucose polymer dissolved in 1 L of water or diluted sugar free squash. Add 1/5 th of a tsp of salt. 3. Fruit juice diluted in the ratio 50:50 with water. Add 1/5 th of a tsp of salt to every litre. 4. Fruit squash diluted in the ratio of one part squash to 4 or 5 parts water. Add 1/5 th of a tsp of salt to every litre. Chill drinks before serving. Remember that good dental care is necessary when using sweetened drinks.
Other Athlete Considerations Travel Within the UK Fitting in time to eat uses travel time Pack food, snacks and drinks Do not rely on venue at competitions Remember to drink Travel Abroad Fussy eaters are hard to feed Some foods may need to be taken Check the venue and foods available Check the water is safe Avoid certain foods (shell-fish, ice-cream, curries)
Populations at risk include: females teenagers Vitamin C helps absorption athletes vegetarians Iron and Anaemia Iron is well absorbed from animal sources - less well absorbed from plant sources
Risk of osteoporosis is increased if: Body weight is low Periods are missed or stopped Calcium intake is low due to milk intolerance or low food intake There is an absence of weight bearing exercise. Calcium
Anorexia nervosa Individuals will be thin Body weight is maintained by: - very low food intake Eating Disorders Bulimia nervosa Individuals may not be thin Body weight is maintained by: - use of laxatives - vomiting Food is eaten in very large quantities during binges Anorexia athletica Individuals will be lean Body weight is maintained by: - very low food intake - excessive exercise - use of laxatives - vomiting
SUMMARY Always eat a balanced diet Drink 2 litres of water each day Eat plenty of carbs before, during and after exercise Avoid fried and fatty foods where possible Avoid large gaps between meals – little and often
Compiled by: Mistrelle Baker
For further information / advice…. Mistrelle Baker