England Athletics Workshop

1. NUTRITION FOR PERFORMANCEBy Mistrelle Baker 23 February 2010 England Athletics Workshop

2. Nutrition for Optimal Health and Performance • Are you eating the right foods to be the best?!!

3. GENERAL NUTRITIONKey Points : 1. Healthy food 2. Nutrition for training 3. Recovery and performance

4. NUTRITION FOR HEALTH

5. 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?

6. BALANCED EATING 2. 1. • Bread, cereals, potatoes, rice • 55-65% of daily food. • Fruit & vegetables • Eat 5 portions every day (include variety) 3,4. Meat & fish / dairy products • 10-15% of daily food -choose low fat versions • Fats and sugars • 20-25% of daily food - unsaturated fat rather than saturated fat 4. 3. 5.

7. 1. BREAD, CEREALS, POTATOES, RICE • Complex carbohydrates • Should form basis for meals • Combine different forms for each meal • Replace fuel stores • Optimise performance

8. 2. FRUIT & VEGETABLES • Performance & recovery • Vitamins & minerals • Iron, potassium, calcium, chromium, niacin, phosphorous, biotin, zinc, vits A, C, E, B1, B2, B6, B12.

9. 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

10. 4. MILK & DAIRY FOODS • Performance & recovery • Fat and protein • Energy source, bone & teeth strength, muscle & tissue repair

11. 5. FATTY & SUGARY FOODS • Use fats sparingly! • Sweets may be used to aid recovery!

12. NUTRITION FOR PERRFORMANCE

13. How can food and drink affect performance? • Provide and replace fuel stores • Repair and strengthen damaged muscle tissue • Replace fluid losses

14. 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

15. Fuel for Sport • High Intensity Exercise: (eg field events, sprints) Fat Carbohydrate Carbohydrate is the only provider of energy for high intensity activities

16. Fuel for Sport • Medium Intensity Exercise (eg middle distance running) Fat Carbohydrate Carbohydrate is the main provider of energy during medium intensity activities

17. OHT 5 Fuel for Sport • Low intensity Exercise: (eg long distance running/cycling) Fat Carbohydrate As duration continues the contribution of fat increases

18. 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

19. Practical Recommendations for Carbohydrate Intake Considerations • Type • Amount • Rate • Timing

20. Daily Requirements • 125 - 175g • 55-65% total intake • Complex (⅔) and simple CHO (⅓) • Limited stores of glycogen (800-2000kcal) • Dependent on: • Exercise intensity • Exercise duration • Diet • Body size • Fitness status

21. Type • Glucose, sucrose, maltodextrins (6-8% solution) 2. Liquid versus solid 3. Low versus high glycaemic index foods

22. 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

23. Amount • Before • During exercise • After exercise

24. 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

25. Adverse effects • Injury • Irritability • Decreased ability to train • Dizziness • Fluid loss • G-I disturbance • Weight gain

26. 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

27. Practical Recommendation(Amount) C. AFTER • Dependent upon type of recovery • Active • Passive rest • Muscle damage / soreness • Time-course of recovery • See ‘Rate’ for recommendations

28. 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

29. Practical Recommendations(Rate) • Frequent feedings over first 4-h • 0.4g maltodextrin, every 15mins • Highest level of glycogen resynthesis

30. Timing A. Immediately post-exercise B. First 2 hours post-exercise C. Immediate versus Delayed intake D. 4 hours post-exercise

31. Practical Recommendation(Timing) • 100-150g 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)

32. Excess (simple) Nutritional deficiencies Obesity High cholesterol Dental problems Gastrointestinal irritation Deficiency (complex) Tissue wasting (extreme) Homeostatic imbalance Severe fatigue Lack of alertness Inappropriate CHO Intake

33. FLUID INTAKE • 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

34. Water • ~60% of total body weight • Intracellular and extracellular • Functions • Transport medium • Structural part of body tissues • A lubricant • Component of chemical reactions

35. 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

36. Dehydration • Decrease in total body water • Rapid fatigue • Performance reduction

37. Hypohydration • Aesthetic appearance / weight category sports • Athletes voluntarily dehydrate • Negative affects upon performance • Short-term adverse health effects

38. Hyponatraemia • During exercise • Low plasma sodium concentrations • Consumption of excess water • Sodium intake is low / losses are high • Fatigue • Nausea

39. 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

40. 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.

41. 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

42. 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.

43. Practical Recommendations • BEFORE • 2 h : 500ml fluid • Glucose / water solution with salts • DURING • 600-1200ml.h.-1 • Maintain plasma volume • Control electrolyte balance • AFTER • Replace water and electrolyte losses • Solid and fluid intake • Continue until urine is pale yellow

44. Recipes for home-made sports drinks • 60g of glucose dissolved in 1 L of water or diluted sugar free squash. Add 1/5th of tsp of salt. • 60-100g glucose polymer dissolved in 1 L of water or diluted sugar free squash. Add 1/5th of a tsp of salt. • Fruit juice diluted in the ratio 50:50 with water. Add 1/5th of a tsp of salt to every litre. • Fruit squash diluted in the ratio of one part squash to 4 or 5 parts water. Add 1/5th of a tsp of salt to every litre. Chill drinks before serving. Remember that good dental care is necessary when using sweetened drinks.

45. 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)

46. Iron and Anaemia Populations at risk include: • females • teenagers Vitamin C helps absorption • athletes • vegetarians Iron is well absorbed from animal sources - less well absorbed from plant sources

47. Calcium 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.

48. Eating Disorders Anorexia nervosa Individuals will be thin Body weight is maintained by: - very low food intake 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

49. 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’

50. THAT’S ALL FOLKS!! Compiled by: Mistrelle Baker Any Questions?