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: – 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:

• 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.

SummaryBefore event Training

intensityDuration Diet

7 days 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 NBAffects 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…