Eat to compete: Sports Nutrition for Athletes

Paula Hynd BSc SRD ASD
Accredited Sports Dietitian

Why is what you eat important?

• Top level sport places high energy demands on athletes power and endurance
• An unbalanced diet can lead to fatigue and injury which affects training
• Weight may affect performance
• Recovery between sessions helps to maintain level and volume of training
  
  

What is a healthy diet?

One which supplies optimum energy and essential nutrients:      

Energy (calories)
Carbohydrate
Fat
Protein
Vitamins and minerals
Fluid
Amount of energy needed depends on age, sex, weight and exercise:
Intensity                      
Frequency
Duration

Energy Balance

• Energy In=Energy out=Steady body weight
• Most athletes will need up to 3000 calories per day to maintain weight
• Insufficient calories can lead to poor growth, deficiencies, bone deficiency, injury risk and distorted body image
  

What is a healthy diet?

• Enjoy your food
• Eat a wide variety of different foods
• Eat the right amount to maintain a healthy weight
• Eat plenty of foods rich in starch and fibre
• Do not eat too much fat
• Do not eat sugary foods too often
•  Be sure to get enough vitamins and minerals from food
  

How can a healthy diet apply to athletes?

• As physical activity increases a larger quantity of foods can be enjoyed
• Most athletes find they perform well within a narrow range of body weights so should not overeat
• To get in enough carbohydrate some sugary foods will be consumed as starch can be too bulky in large quantities
  
  

Bullseye Fuel: Carbohydrate

• Most important nutrient for sporting performance
• Primary fuel for muscle contraction
• Body can only store limited amounts so daily intake necessary
• Demand for this increases as intensity increases
• Fat or protein cannot supply energy at 65% of maximum
• 30 minutes at greater than 90% maximum can totally deplete the body’s store of glucose called glycogen (stored in muscles and liver)
  
  

Bullseye Fuel: Carbohydrate

After 2 hours at 60-80% max muscle glycogen is depleted and fatigue can set in Glycogen depletion or low body carbohydrate stores can cause:

• chronic fatigue
• reduced recovery
• poor quality training
• Complete restocking of glycogen stores after training can take up to 20 hours and only achieved with a high carbohydrate diet or recovery is poor
  
  

How much carbohydrate do I need daily?

7-10g carbohydrate for every kg body weight

7 stone person (43kg)
43 x 7= 300g per day

10 stone person (64kg)
64 x 7= 450g per day

Athletes doing 4-6+ hours per day need 10-12g carbohydrate/kg/day

Timing of Carbohydrate intake

• Immediately after exercise, glycogen is restored at a 7 % faster rate
• Eating/drinking carbohydrate rich foods at a rate of 1-1.2g per kg within the first two hours consumed in the dressing room/car not waiting till home
• Avoid high fat foods e.g. chocolate as they reduce appetite and can reduce overall carbohydrate intake

Different types of Carbohydrate

• Glycaemic index (GI) is a ranking of foods based on their immediate effect on your blood sugar
• Carbohydrate foods with the highest GI are digested quickly (called high GI) and include sugar and sweet foods these can be consumed during and after exercise
• Low GI foods are slowly digested and include all bran, apples, granary bread
  These are consumed more than 2 hours before exercise as they are slowly digested
  
  

How do I increase my carbohydrate?

Snack attack: Eating little and often rather than 3 large meals per day

Practical ideas: thick bread, more pasta/rice/potatoes than meat/sauce, more bread than filling on sandwich,bread with pasta for tea, potatoes or oven chips, use excess rice/pasta for next day lunch, breakfast cereal at any time of day, add fresh fruit to cereal, add potatoes or pasta or beans to soup or pasta sauce, low fat milkshakes.

How do I increase my carbohydrate?

Snacks: Cereal (sugary types are ok e.g. crunchy nut cornflakes), can of rice pudding, bananas and fruit, crumpets, pancakes, scones, malt loaf, toasted teacake, low fat yoghurt, cereal bar e.g. elevenses or nutrigrain, fig rolls, jaffa cakes, low fat chocolate e.g. crunchie or turkish delight, pretzels or twiglets or lite crisps, plain popcorn, tuna, prawn or chicken salad sandwich, sports drink

How much fat do I need?

• About 25-30% of your total calorie intake should come from fat
• If you need 3000calories per day, this means you should eat 85-100g of fat
• Fat is not a limiting factor in exercise and the body has ample store
• Aim to limit the occasions you eat high fat foods to keep intake low
• On food labels aim for <5g fat/100g food
  
  

How to Keep Fat Intake Low

Choose low fat dairy products
Low fat spread, semi-skimmed or skimmed milk, low fat natural or flavoured yoghurt, low fat cheese e.g. edam/gouda/cottage cheese

Limit consumption of crisps, chocolate, pastries, rich cakes and biscuits.  Low fat alternatives instead.
Grill or bake meats/fish/chicken.  Canned fish in brine.  Dry fry with oil spray.
Oven chips, skin and fat removed from chicken and meat, skim fat off mince with kitchen paper
Low fat sausages, burgers, limit intake of pies, sausage rolls, yorkshire puddings, pasties

How much protein do I need?

• Tendons and muscles get stronger with training.  This uses more protein
• Without this development injury risk is higher
• Protein requirements for endurance athletes are 1.2-1.4gprotein/kg/day
• This is 77-90g per day for 10stone athlete
  
  

Where do I get Protein from?

• Meat, chicken, fish, eggs
• Peas, beans, lentils, nuts
• Low fat cheese, milk and dairy produce e.g. low fat yoghurt
• Bread, pasta, cereals and rice
• Protein supplements are unnecessary
• Some protein in after event snack helps muscle recovery e.g. bowl cereal or milkshake or glass milk or yoghurt
  
  

Bullseye fuel: Vitamins and minerals

• Some athletes at risk of low intake
• A balanced diet of the four food groups will provide most: aim for 5 portions fruit and vegetables per day
• Supplements: Simple multi vitamin and mineral only to avoid mega-dosing 
  
  

Bullseye nutrition: Fluid

• Dehydration can lead to reduced mental function, poor decision making, anticipation and skill delivery and reduced mental and physical performance
• Thirst is a poor indicator of hydration
• Weight before and after training can help identify fluid replacement needed
  
  

How can I ensure I am well hydrated?

• Aim for 3 litres fluid per day baseline
• Aim for 500ml to 1000ml fluid per hour of training and racing
• Ensure urine is plentiful and clear
• Be organised and take fluid with you everywhere: school/work/on route to training and pack extra for journey home.  Ensure you DRINK it!
  
  

Summary

• Healthy diet
• Additional carbohydrate to meet demands of training and racing - know how much you need and how to get it
• Keep fat intake low (LOW but not NO fat)
• Protein as for a healthy diet with extra in recovery snack
• Vitamins and minerals: 5 Portions fruit and vegetables every day
• Fluid is absolutely essential to performance
• Don’t try any new nutrition strategy on race day – ensure it is well tried out in training first!
• Sports supplements do not make up for an unbalanced diet – get the basics right first!