Download High training loads

Nutrition for
Performance
Objectives
• Identify the components of a healthy, balanced diet
• Recognise the key macronutrients required to lead a healthy lifestyle,
and their important role/s in the body
• Understand the difference between eating for health and performance
• Describe the Glycaemic Index and it’s importance
• Identify the importance of hydration for performance and the
implications for a rider
• Consider the use supplementation and identify possible issues for
athletes
Nutrition
• Why do we need food?
– Provide energy for the body to function
– Provide energy for training
• Fat: 9 cal/gram or 37 Kilojoules/gram
• CHO: 4 cal/gram or 16 Kilojoules/gram
• Protein: 4 cal/gram or 16 Kilojoules/gram
– Help the growth and repair of muscle and body tissue
– Help avoid and fight infection
• Nutrition is recognised as a potential performance factor, together with
speed, power etc.
Dietary Nutrients
Carbohydrate
• Sugar
– Pass into blood stream very quickly
– Food/drink sources include soft drinks, sweets, honey, fruit
juice dairy (i.e. yoghurt/milk) and fruit
• Starch
– Food sources Include pasta, cereals, breads, rice and
potato
• Starchy carbohydrates are broken down into sugar in the body, and
are either stored in the liver or muscle as glycogen.
• The liver can hold much more glycogen than skeletal muscle
• Glycogen is broken down into glucose to be used for energy
• After glycogen stores are full, excess dietary carbohydrate is
converted to fat in the body
• The amount of glycogen that can be stored is limited (approximately
enough for a 1.5-2 hours, zone 3 ride)
Dietary Nutrients
Protein
– Essential for the growth & repair of the bodies tissues
– Proteins are made up of amino acids (20)
• 12 – Non essential (synthesised by the body)
• 8 – Essential (not synthesised by the body)
– Essential Amino Acids must be supplied through diet
– Animal food sources are considered to be of high biological
value as they contain all the essential amino acids to build
muscle tissue
Dietary Nutrients
Fat
– Provides the most concentrated source of energy
– Saturated – raises LDL i.e. Bad cholesterol – food sources include:
–
–
–
–
–
–
Butter
Cheese
Chocolate
Cream
Full fat dairy
Cakes
– Monounsaturated - food sources include:
– Olive oil, avocado, cashew nuts, almonds
– Polyunsaturated - food sources include:
– Oily fish e.g. salmon, fresh tuna (not canned) - important source
of omega 3 which is good for concentration/heart
health/inflammatory processes
Dietary Nutrients
Fat
– Fat is used primarily for low intensity endurance exercise
– Fat fuels are not as efficient as carbohydrates as more O2
is required
– However there are greater fat stores in the body than CHO
Dietary Nutrients
Water
– Key role in sustaining life
– 55-65% adult body is water
– Adequate levels of fluid are essential for;
– Optimum storage of glycogen
– Maintenance of the body’s core temperature
Vitamins and Minerals
– Vitamins assist with growth and maintenance of body functions
– Minerals regulate the body's functions
Dietary Nutrients
Dietary Fibre
– Roughage that is not digested by the body
– 2 types: insoluble and soluble
– Soluble: Helps to keep bowels healthy and prevents constipation. Found in
fruit and vegetables.
– Insoluble: decreases blood cholesterol. Found in oats, pulses and
legumes.
Eating for Health
•
•
•
Riders of all levels should initially focus on a healthy, balanced diet
Avoid short cuts (i.e. supplementation)
Variety
Breakdown of Total Energy for Health
Carbohydrate
55-60%
Fat
20-35%
Protein
15-20%
Eating for Performance
Dietary recommendations for performance similar to health
Higher % CHO, lower Fat and Protein
Increased volume of food
Breakdown of Total Energy for Performance
Carbohydrate
60-70%
Fat
20-25%
Protein
10-15%
Eating for Performance
Standard training loads
– 7g of CHO per kilogram of body weight
– 1.2g of protein per kilogram of body weight
High training loads
– 10g of CHO per kilogram of body weight
– Up to 2.0g of protein per kilogram of body weight
Example: 75kg rider completing standard training load
– 525g of CHO per day
– 90g of protein per day
Eating for Performance:
CHO & Protein
Time
Breakfast
During ride
Post ride
Lunch
Amount of food
4 x wheetabix
300ml skimmed milk
Sprinkled with raisins (1 tbs)
250ml fruit juice
800-1000 mls sports drink
Fruit smoothie (300ml milk, 1 x
banana, 2 tbs honey)
4 slices granary bread
100 grams canned tuna
+ salad
1 x apple
Amount of CHO (g)
Amount of Protein (g)
51.4
15
17.3
25
9
10.2
0.5
Trace
50
70
Trace
10.2
57.6
Nil
22
25
10
Trace
During ride
Post ride
2 x CHO gels
Fruit smoothie (milk, banana/s,
natural yoghurt, honey)
50
70
Trace
10.2
Dinner
200grams cooked pasta (100g
uncooked)
100g of grilled fish + salad/veg
50g of cheese
73
12
Nil
Nil
20.2
12
37.1
5.5
526 g
7g/kg BW
136g
1.8g/kg BW
Snack
1 carton of yoghurt + ½ can
stewed fruit (natural juice)
TOTAL
Glycaemic Index
• The glycaemix Index is a ranking of CHO foods on a scale from 0100 according to how they affect blood glucose levels.
• 3 categories:
• LOW (<55) – e.g. Oats/lentils/fresh fruit/yoghurt/sweet potato.
• MODERATE: (55-69) – wheetabix, wholemeal bread, dried fruit,
new potato.
• HIGH: (>69) – Jasmine rice, sweets, white bread etc.
• One of the critical factors for performance is how readily available
glucose is to a rider
• Glycaemic Index (Gi) provides a measure of how fast and how
much a particular food raises blood glucose levels
• The GI can therefore be used to assist the selection of appropriate
foods at the appropriate times
Glycaemic Index
• Before exercise:
– Low to Moderate GI
– 2-3hrs prior to exercise
– Long and sustained release of glucose into the blood
• During exercise
– High GI
– Provides a rapid release of glucose into the blood
• Post exercise
– When?
• Immediate – High GI (e.g. sports drink)
• Extended – Medium GI (e.g. yoghurt and fruit)
Glycaemic Index
Time
Glycaemic Index
Examples
Before exercise
Low/moderate





Porridge
Fruit (eg pear, apple, orange, plum, peach)
Dried fruit (eg prunes, apricots)
Breakfast cereal (eg All-Bran, muesli)
Skimmed or low-fat milk
During exercise
High


Energy gels (exercise lasting longer than 60 minutes)
Sports drinks (exercise lasting longer than 60 minutes)
After exercise
High (immediately
after exercise)





Sports drinks
Cornflakes
Rice cakes
Bagels
Bananas
Low/moderate
(1-2 hours after
exercise)







Wholemeal bread
Potatoes
Rice
Couscous
Instant oats
Breakfast cereals (eg Special K, Weetabix)
Pasta
Race Feeding Strategy
Road Race
What ?
How much ?
CMC TRAINING SESSION
18
Race Feeding Strategy
• Endurance disciplines (>2hrs) requires careful consideration for
feeding during the race
Why does it help?
• Maintains concentration of blood glucose – provides a constant
supply of glucose
• Helps maintain high rates of carbohydrate oxidation
• A regular intake of CHO ‘saves’ glycogen breakdown in liver and to
a small effect muscles (protects stores)
• Improves performance and delays the onset of fatigue
CMC TRAINING SESSION
19
Race Feeding Strategy
• Different types of CHO
– Separated by ‘rate’ of oxidation
– Slow oxidation – up to 30g / hour
– Fast oxidation – up to 60g / hour
Slow
Fast
Fructose (fruits)
Glucose (breakdown of starch)
Galactose (sugar beets)
Sucrose (table sugar)
Isomaltulose (honey)
Maltose (two glucose molecules)
Amylose (starch breakdown)
Maltodextrins & Amylopectin (starch
breakdown)
CMC TRAINING SESSION
20
Race Feeding Strategy
How much carbohydrate and which type?
•
‘Optimal’ intake is the maximum amount of CHO that results in highest CHO
oxidation
•
Is more better?
– ‘The pack says one scoop, so I’ll give myself two. It must be better!’
– Do you include as much CHO into a drink as possible?
•
Limits of uptake
– Human intestines use specific ‘transporters’ to move CHO from the intestinal
space, through the intestinal wall and into the blood.
– Limited availability of ‘transport’ across the intestinal wall
– At full capacity, glucose has a transport limit of 60g / hour
CMC TRAINING SESSION
21
Race Feeding Strategy
How much carbohydrate and which type?
•
Are there other transporters available?
– Fructose uses a different transporter
– Therefore could a combination of Glucose and Fructose increase the CHO
update?
•
Glucose and Fructose mixes shown to increase CHO oxidation with a 2:1
ratio
– Glucose: 60g / hr
– Fructose: 30g / hr
– Interestingly, if glucose is not at it’s ‘maximum’ (ie. 60g/hr) the increase oxidation
is not seen
CMC TRAINING SESSION
22
Race Feeding Strategy
Race Feeding Strategy
•
Many different combinations of CHO have been research
– Currently the following combinations have been identified as the most beneficial
CHO Type
Amount
Glucose + fructose
60g / hr + 30g / hr
Maltodextrin + fructose
60g / hr + 30g / hr
Glucose + sucrose + fructose
60g / hr + 15g / hr + 15g/ hr
– Maltodextrin is less sweet than both glucose and fructose, therefore it may be
easier to consume
•
Are the above rates affected by body mass?
– No changes seen by variation in athletes mass
CMC TRAINING SESSION
24
Race Feeding Strategy
Solid CHO v Liquid CHO?
•
Energy bars and Gels V drinks?
– Equally as effective at increasing CHO oxidation rates as ingesting a CHO drink
– Therefore providing greater range and ‘comfort’ for athletes to choose a multiple
range of CHO sources
•
Types of solid race food?
– Pastries / cakes are the ‘traditional’ food choice that typically are high in fat
– Look at alternatives – rice cakes, small sandwiches etc, with lower fat
CMC TRAINING SESSION
25
Race Feeding Strategy
Carbohydrate intake during exercise
Event
< 30min
Suggested
intake
CHO
No CHO needed
CHO Type
Glu
Glu +
Fru
-
-
-
-
30 – 75min V small amounts
Small sips /
mouth wash
Most forms of
CHO
Yes
Yes
1hr – 2hr
Small amounts
Up to 30g/hr
Most forms of
CHO
Yes
Yes
2hr – 3hr
Moderate
amounts
Up to 60g/hr
Rapidly oxidised
CHO
Ok
Yes
-
Yes
(glucose, Multodextrins)
2.5hrs +
Large amounts
Adapted from A. Jeukendrup, INSEP Eat to Win conference
Up to 90g/hr
Multi-transport
CHO
CMC TRAINING SESSION
26
Hydration
•
•
Crucial for health and performance
For optimum performance water and electrolyte balance must remain
constant
•
•
•
•
Dehydration by as little as 2% loss of body weight starts to impair
performance
Dehydration in excess of 5% loss of body weight can decrease work
capacity by 30%
Heat illness can occur when 5-6% body weight is lost
MYTH – dehydration cannot be tolerated or trained – any dehydration will
reduce performance
Hydration
How to combine CHO intake whilst maintaining
hydration in different environments?
Hydration
What to Drink, When to Drink
•
Isotonic drinks
– CHO of 5-8%
– Provides source of energy, without impairing fluid absorption
– Use pre, during and post training / competition
•
Hypotonic drinks
– Contains CHO and salt
– Limited CHO, therefore limited contribution to performance
– Useful in hot conditions
•
Hypertonic drinks
– CHO of 10% +
– Could limit hydration purposes
– During and post training competition
•
Some evidence suggests that glucose + fructose combinations aids delivery
of water compared to just glucose.
Hydration
Recommended drinks for varying intensities and durations
Exercise Intensity and Duration
Type of Drink
•
Low/moderate/high – less than 30
minutes
•
Water/diluted squash
•
Low/moderate – less than 60 minutes
•
Water/diluted squash
•
High – less than 60 minutes
•
Isotonic sports drink
•
High - longer than 60 minutes
•
Isotonic sports drink
Hydration
Approximate fluid intake requirements per hour
Temperature
Body Weight
(up to 14ºC)
Kg
(15-24ºC)
(over 25ºC)
Fluid Requirements in ml
40-50
200-300
300-450
450-550
50-60
250-400
400-500
500-600
60-70
300-450
450-500
550-650
70-80
350-500
500-650
650-750
80-90
400-550
550-700
700-850
Pre-Race Meal
• Pre-Race meal tops up stores and keeps the stomach
comfortable during races
• Keep meals familiar and individual
• Track:
– Multiple competitions
– No feeding during races
– Easy access to regular feeding (track centre)
• Road:
– Normal sized meal 4hrs before race (high CHO, low fat)
– Include a small snack 2hrs before
– If a rider suffers from pre-race nerves, try a liquid meal supplement or a fruit
smoothie as a pre-race meal.
– Include fluid throughout
Carbohydrate
Loading
• Strategy involving altering training and diet, to maximise stores of
glycogen (carbohydrate) prior to competition
• Original design required 3-8 days
– 3-4 day Depletion Phase (high training load & low CHO)
– 3-4 day Loading Phase (low training load & high CHO)
– Negative effects of strategy included impact on training, reduced mental capacity
and changes in mood state.
• Amended design requires 3-4 days
– 3-4 day Loading Phase (tapering training load & high CHO)
– Limited effects of strategy on training, mental capacity or mood state.
• Both designs shown increases in muscle glycogen stores:
– 100-120 mmol/kg ww – normal glycogen levels
– 150-200 mmol/kg ww – post loading
Carbohydrate
Loading
• Some research indicates that female riders may be less responsive to
CHO loading than males
• More research is needed
• Common mistakes
– Not combining appropriate dietary intake with training load taper
– Athletes gorging on food to increase their CHO intake
– Fear of weight gain preventing athletes from loading properly
• Body mass can increase by 2kg
– Not reducing intake of dietary fibre, leading to discomfort because
of volume of food required
– Not maintaining appropriate hydration
Carbohydrate Loading:
Example daily diet
Time
Breakfast
Food
3 cups of low fibre cereal & 1.5 cups of low fat milk
1 medium, ripe banana
250ml apple juice
Snack
500ml sports drink
Toasted white bread with jam
Lunch
2 sandwiches (4 slices of bread) with salad and tuna filling
2 x 125g low fat yoghurt
375ml can of soft drink
Snack
Dinner
Snack
Fruit smoothie (low fat milk, 1 banana, 1 tablespoon of honey
Cereal bar
2 cups of pasta
1 cup of tomato sauce
3 slices of bread
2 glasses of squash
Toasted muffin and honey
500ml sports drink
Sample Plan contains approximately: 650g Carbohydrates, 125g Protein, 60g Fat
Post-Race / Training
Meal
•
Focuses on the replenishment of energy and rehydration
•
Immediately:
– Within first hour
– CHO & Protein has been shown to aid replenishment of glycogen
stores
– For every 4g of CHO, 1g of Protein
• E.g. Rice & tuna (CHO, Protein)
• Rice also helps to ‘rehydrate’ given it’s high water content
•
Delayed:
– Within 2hrs
– A CHO rich meal with protein included
– Don’t forget micro-nutrients!
•
Consider post race ‘availability’ of food
– Media, anti-doping, massage etc.
Supplements
•
What are supplements?
– Additional sources of either macro or micro nutrients taken in addition to
standard meals
•
Endurance cycling is one of the most demanding of disciplines: Can a
rider get all nutrients they need from food alone?
– Yes, but it is not always practical
•
What role do supplements play?
– Convenient, support performance
•
Are there any potential issues of taking supplements?
– Possible contamination, dependency, incomplete nutrition
Supplements
•
•
Should be viewed as ‘supplements’ to diet, not replacements
Check evidence claims
– Endorsements by athletes / coaches
•
•
•
•
•
No guarantee
Use based on dietary requirements
Supplements are unregulated and may contain prohibited substances that
are not listed on the label
Claim to be ‘IOC’ or ‘WADA’ approved but the IOC or WADA do not endorse
supplement products
No guarantee can be given about the safety or legality of supplements
Fact or fiction
Skipping breakfast help athletes loose weight
• Fiction – blood glucose levels will already be low as athletes may not
have eaten for 8-12 hours. Skipping breakfast decreases the
metabolic rate which makes it harder to burn calories.
It is important to eat a CHO snack before an event
• Fact – fuelling the body with carbohydrate before training or an event
is beneficial to provide fuel so that muscle glycogen stores last longer
You don’t need to eat after exercising
• Fiction – it is important to fuel the body firstly with a high GI CHO food
source to start replenishing glycogen stores. Ths is especially
important if the next major meal is delayed.
Fact or fiction
You can get all the nutrition you need from energy bars
•
Fiction – Energy bars can contain the same amount of calories as a
small meal (e.g. sandwich & fruit). Therefore, they are unsuitable for
athletes performing very light training schedules. They should only be
used if athletes require more CHO/energy which cannot be met
through eating increased volumes of food. In this situation, energy
bars should compliment not supplement their meals
You need to loads of protein to enhance performance
•
Fiction – CHO is the nutrient that will enhance performance. It is the
body’s preferred fuel. It is still important to follow the recommended
guidance for protein intake, but it is not an effective energy source.
Fact or fiction
It is better to drink sports drinks containing sodium
rather than water when competing in hot climates
• Fact – in hot, humid environments dehydration is a particular concern
for those athletes who sweat heavily, those who perform for long
periods or athletes who are acclimatising to a hotter climate or going
to altitude. Sports drinks containing sodium in these situations are
more suitable than water to replace the electrolytes lost with sweat
You can eat whatever when you want when you train
• Fiction – Athletes can generally consume more total energy. However,
increased energy requirements should come from CHO not fat. Athletes
should not eat too many high fat or treat foods as this could compromise
training and recovery.