Transcript Lecture 11b powerpoint

SPORTS NUTRITION
16 NOVEMBER 2015
Why Are Good Nutritional Practices
Important For Athletes?
Enhances Training and Competitive
Performances
• Provides Adequate Nutrients For
Recovery Between Sessions
• Maintains Good Health
• Sustains Growth & Development
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“A Proper Diet Can’t Make An Average
Athlete Elite, But A Poor Diet Can Make
An Elite Athlete Average”
What Are The Issues?
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Energy – Macro Nutrient Intakes For Various Sports
– Do They Differ?
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Hydration – does it affect performance?
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Timing – When should athletes eat/drink?
Carbohydrates
Why Do Athletes Need Them?
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Primary fuel source for most groups of athletes
• Primary fuel source for endurance athletes is
fat but limiting fuel source is carbohydrate
CARBOHYDRATES
What Are The Foods Sources?
Grain Products
Vegetables and Fruit
Milk Products
Extras
Carbohydrates –How Much Do Athletes Need?
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Endurance Athletes & Athletes Who Train
Exhaustively On Successive Days –60-70 %
of total energy–If consume high energy
diets then need 7-10 g/kg/d
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Recreational Athletes & Most Active People –
55-60 % of total energy
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Strength Athletes - ~ 55–65% of total energy
– Depends on Training Schedule
FAT
Why Do Athletes Need It?
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Provides Fat Soluble Vitamins (A,D, E, K)
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Supplies Essential Fatty Acids
• Taste
• Aids With Satiety
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Primary Fuel Source For Endurance Athletes
FAT
Where Athletes Get It?
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Naturally Present In Many Foods
– Hidden vs Added Fats
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Majority Of Fat In Diet From Fats & Oils
– i.e. Butter, Margarine, Salad Dressings,
Sauces
FAT-too much can slow down the athlete
How To Reduce Intake
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Choose Lower Fat Foods
i.e. Leaner meats, lower fat dairy products,
low fat salad dressings
Trim Fat From Meats, Skin From Poultry
Prepare Food Without Adding Fat
Choose Appropriate Serving Sizes
Avoid Adding Fat When Possible
i.e. butter, margarine, gravy,
mayonnaise, sauces
Protein
Why do athletes need it?
• builds muscle and bone
• make enzymes-required for energy
and building molecules
• to meet all other functions of proteins
Protein
Where do athletes get it?
• Meat and alternatives
• Milk and alternatives
• Grain products
Protein Recommendations
Dietary reference intake-for healthy nonathletes
– 0.80 grams/kg body weight/day
Athletes:
– Strength: 1.4-2.0 grams/kg body
weight/day
– Endurance: 1.2-1.6 grams/kg body
weight/day
Protein Recommendations
How much do athletes need?
Example
• 80 kg Male
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Normally Active: 0.80g/kg BW/day~ 64 grams/day
Strength Athlete: 1.4-2.0g/kg BW/day ~110-160 g/day
Endurance Athlete: 1.2-1.6g/kg BW/day ~ 95-130g/day
Protein Recommendations
Can You Consume Too Much
Protein?
No Adverse effects have been reported
for Healthy Athletes when Protein
intakes are <2.0 g/kg BW/day
Water-Why Do Athletes Need It?
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Water Assists in the Digestive Process & Elimination
of Waste Products
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Major Component of Blood
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Acts as a Coolant for Working Muscles &
Maintains Normal Body Temperature
Water-Where Do Athletes Get It?
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drinks-water, juices, milks, sports drinks, tea, coffee
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semi-solid and solid foods have some water
Water-how much do athletes need?
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replace what lose-assuming normal water balance
to start
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normal water balance means sufficient water where
and when it is needed in the body
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avoid dehydration
Fluid Losses Experienced During Training
Athletes typically only replace 30-70% of
sweat losses during a training session
• Therefore, athletes are moderately
dehydrated post-exercise
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Continued fluid loss in recovery phase:
Sweat
Urine production
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Goal:
• Replace fluid lost during training prior to
next event
Dehydration
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Starts When fluid Loss Exceeds 1% of Body Weight
Symptoms:
– Headache
– Irritability
– Fatigue
Impact of Dehydration
Replacing Fluids During Activity
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Thirst is not a Good Indicator
Water is Best Fluid if Activity is Under 1 Hour
Activities > 1 hour would benefit from a carbohydrate
source (6-10% CHO)
Cool Fluid in Small Volumes
Drink ~ 125 ml every 10-20 minutes
Is Plain Water Enough?
Recommendation:
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Athletes experience >2% loss of body weight from
dehydration
Consume ~150-200% of volume lost
Fluid should contain sodium
Also consume some foods containing sodium
post-exercise
Recommended levels of sodium: 50mmol/Litre
Sports Drinks: 10-25 mmol sodium/L
Remember:
When selecting a fluid for re-hydration, the fluid has to be
palatable to the athlete. This has been shown to increase fluid
consumption
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Vitamins and minerals
Why do athletes require them?- to allow their
functions
Where do athletes get them-in carbohydrate, fat
and protein containing foods
How much do athletes require-amounts found in
sufficient intake of foods containing carbohydrate,
fat and protein
Supplements are a waste of money
PRE-COMPETITION MEALS
• Assume a Sound Training Diet Has Been
Consumed
• Replace Liver Glycogen Stores That Have
Become Depleted Over Night
Pre-Competition Meals
Purpose:
• To Prevent Hunger During the Competition
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To Assist with Adequate Hydration
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To Increase the Physical & Psychological
Comfort of the Athlete
Pre-Competition Meals
Timing
2-4 hours before event to allow adequate
digestion
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Meal Size ~ 500 kcals
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Meal Time ~ 2-4 hours before
• Competition – If < 2hours before
competition, smaller meal is required
Foods Must Be Familiar To The Athlete
Pre-Competition Meals
Composition:
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High Carbohydrate
Plenty of Fluids
Moderate in Protein Content
Low in Simple Sugar Content
Low in Fibre and Fat
Low in Salt & Caffeine
Fueling After Action
Replace:
– Water
– Glycogen Stores
– Electrolytes (and other minerals)
- Plenty of Fluid
-1.5 litres of fluid for every kg weight loss
- Carbohydrate
– Within 2 hours after activity
– Fruit, juice, crackers, bagels,
lower fat yogurt
– Ensure a full meal with adequate
intake
Nutrition Does Impact Performance!