Transcript Nutritional Supplementationx

Nutritional Supplementation
Dietary Supplements
• Products intended to supplement the diet that
contain at least one dietary ingredient to include:
– Vitamins
– Minerals
– Herbs or other botanicals
– Amino acids
– substances such as enzymes,
organ tissues & metabolites
Dietary Supplements
• These products are taken by mouth.
• These products are found in many forms to include:
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Tablets
Capsules
Softgels
Gelcaps
Liquids
Powders
Bars
Protein
• Background:
– Proteins are linked amino acids that occur
naturally in foods
– Protein supplementation can include: powders,
shakes and bars
Protein
• Claims include:
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Improved muscle growth and function
Increased weight gain
Increased lean muscle mass
Increased strength/power
Protein
• Potential side effects:
– High protein intake can displace carbohydrate in
the diet  affects performance
– Increased urinary calcium loss
– Contribute to dehydration
– Stress on the kidneys  individuals with kidney
disease should avoid high protein diets
Protein
• Research findings:
– Protein requirement in athletes is higher than
non-athletes.
– Most research studies do not support
supplementation as having a positive effect on
muscle size & function.
– But: research may be affected by the fact that
most athletes consume levels of protein that
exceed recommended amounts.
Sports Drink Consumption
• Evidence supports enhanced endurance
performance vs water in events >60 min
• No benefit from added protein
Carbohydrate
Loading
• Can increase muscle glycogen levels 13% 100%
• Prolongs time to exhaustion 2-3% in
endurance events >90 minutes
• Higher effect in untrained persons
Carbohydrate loading and sports
• Carbo-loading is effective only
in endurance activities that
exceed 90 minutes.
• Sports include: marathon
running, long distance
swimming, cycling, cross
country skiing.
• Doesn’t work well in team
sports & sprinting.
What is carbohydrate loading?
Carbo-loading (Supercompensation):
• Legal method of boosting the amount of
glycogen in the body prior to a competition.
• Strategy involving changes to training and diet that can
maximize muscle glycogen (carbohydrate) stores prior to
endurance competition.
• Is meant to increase muscle glycogen stores above normal
levels so it delays the onset of fatigue during a major
competition.
Carbohydrate Loading
 Combining a specific dietary regimen with
exercise produces significant “packing” of
muscle glycogen.
 Normally, each 100 g of muscle contains about
1.7 g of glycogen.
 Carbohydrate loading packs up to 5 g of
glycogen per 100 g of skeletal muscle.
Methods of Carbo Loading
• Classic 6-day regimen
– 3 days intense glycogen-depleting exercise
– 3 days high carb diet, no exercise
• Modified 6-day regimen
– 3-day exercise taper, normal diet
– High carb (70%) & light exercise 3days prior
• Single-day regimen
– 10 gm/kg/day carb 1-day prior
– Normal exercise regimen
How to carbo-load:
Start time is about a week before a major competition.
It involves 2 stages:
1. Depletion stage:
• For the first 3-4 days - eat a minimal amount of carbohydrates
(about 60–100 g/day) to deplete your body’s glycogen storage.
• The body will think that there is a problem with the glycogen
storage within the body = store more glycogen.
• Maintain a moderate training intensity but reduce the duration as
the days go on.
How to carbo-load:
2.
Consumption stage:
• Last 3 days before event- consume high amounts of primarily complex
carbohydrates (400–700 g/day) and reduce the training load of activity.
• Reduce intensity and duration of training sessions to half or a quarter =
body will replenish glycogen stores.
• Diet should consist of 70% carbohydrates for this process to work properly.
NOTE:
 It is especially important that you allow one day of rest to allow your
muscles to store the carbohydrates.
 Supercompensation occurs only in the specific muscles depleted by
exercise.
Summary
Before event
Duration
Diet
7 days
Training
intensity
Moderate
90 minutes
Low carbs/
high protein
6 days
Moderate
60 minutes
Low carbs/
high protein
5 days
Moderate
40 minutes
Low carbs/
high protein
4 days
Moderate
30 minutes
High carbs
3 days
Easy
20 minutes
High carbs
2 days
Easy
20 minutes
High carbs
1 day
Rest
High carbs
Pros and Cons
Pros
• Improve endurance performance
• Improve performance over a set
distance by 2-3%.
• Gives a mental advantage/
improved psychological set
Cons
• Weight gain  store extra water
in the muscles
• Feel tired during the depletion
stage  don’t take in enough
glucose
• Increased blood cholesterol
• Does not increase endurance
with non-athletes
• Symptoms of depletion include
nausea, dizziness & irritability
Modified Loading Procedure
 Reduces some of the negative effects associated with the
classic procedure
 6-day protocol
 Does not require prior exercise to exhaustion
 The athlete exercises at about 75% of VO2max for 1.5 hours
and then, gradually reduces or tapers exercise duration
 During the first 3 days, carbohydrates supply about 50% of
total calories.
 Three days before competition, the diet’s carbohydrate
content then increases to 70% of total energy intake.
Gender Differences
 Women get a smaller proportion of total
energy from carbohydrate break down than
men
 At the same relative workload after training,
women show an exaggerated shift toward fat
break down, whereas men do not.
Important Considerations
• Rate that the stomach empties is NB
Affects absorption of fluids & nutrients
by small intestine
• High fluid volume in stomach = faster gastric emptying
• Consume 400-600ml fluid before exercise  speeds up
nutrient passage to small intestine
• Regularly drink 150-250ml fluid at 15min intervals to
replenish fluid passed into intestine
No substitute for hard work…