1. Which vitamins are antioxidants?
Vitamins E, C, and A. See Vitamin question # 2.
2. What are antioxidants and is it necessary to take them as supplements?
Antioxidants quench free radicals. Three percent of the oxygen that you breathe
goes into producing free radicals rather than burning your fuel. Thus, when you
exercise you produce more free radicals than when you do not exercise. If you eat all of
your carbohydrates in the form of whole grains, fruits and vegetables, you do not need
to supplement with antioxidants . However, endurance athletes take in a significant
portion of their calories in the form of energy drinks and bars (low in antioxidants). For
such people, antioxidant supplementation can provide a benefit (e.g. vitamin C, E, A,
grape seed extract). A better approach is to eat foods naturally rich in antioxidants: dark
fruits (e.g. blueberries, red grapes, red peppers, tomato, citrus, cantaloupe, etc), dark
vegetables (e.g. broccoli, spinach, wheat grass), red wine, tea, and dark honey. A
slightly more complete list of foods, separated into which contain vitamins C, E, and A is
in question #2 of section 8.
3. What is the “glycemic index” and why should I care?
The scientific measurement of how fast a type of food digests is called its “glycemic
index” (GI). The GI of an entire meal is the calorie-weighted average of the GI of the
foods that make up the meal. Fiber, protein, and fat slow down digestion and therefore
have a low GI. Low GI foods keep blood sugar from rising too fast. Rapidly rising blood
sugar results in a huge spike of insulin released from the pancreas. Insulin shuttles
sugar into all organs, particularly fat cells, if the calories in any meal are excessive.
Adrenalin levels at 80% VO2 max inhibits insulin release by a factor of two. This allows
a greater fraction of blood sugars to go to active muscle rather than inactive tissues (e.
g. fat). The glycemic index itself (a list of numbers relating how rapidly different foods
digest compared to each other) was initially developed for diabetics because it is
particularly important that their blood sugar levels are kept as close to normal as
possible (both during and between meals). The way to do this is eat foods that digest
slowly. While I do not recommend that anyone calculates the glycemic index of their
meals, I do recommend that refined carbohydrates (white bread, white pasta, white rice,
and sugar) be minimized except during and immediately following exercise when
adrenalin is present. High-fiber (i.e. low GI) meals will target your carbohydrate intake
to your muscles, allow you to lose weight without heavy caloric restriction, and will keep
your blood sugar normal, which will keep your energy and mental focus high. The most
important times of the day to eat low GI foods is prior to training (see question #3 in
section 3) and prior to sleeping (so that blood sugar is not low during your most
important recovery period). Eating some refined carbs may be necessary during a day
of carbohydrate loading (see question #4 of pre-exercise nutrition), but the refined
carbs should be split up into many meals so that insulin is still somewhat controlled.
Vitamins E, C, and A. See Vitamin question # 2.
2. What are antioxidants and is it necessary to take them as supplements?
Antioxidants quench free radicals. Three percent of the oxygen that you breathe
goes into producing free radicals rather than burning your fuel. Thus, when you
exercise you produce more free radicals than when you do not exercise. If you eat all of
your carbohydrates in the form of whole grains, fruits and vegetables, you do not need
to supplement with antioxidants . However, endurance athletes take in a significant
portion of their calories in the form of energy drinks and bars (low in antioxidants). For
such people, antioxidant supplementation can provide a benefit (e.g. vitamin C, E, A,
grape seed extract). A better approach is to eat foods naturally rich in antioxidants: dark
fruits (e.g. blueberries, red grapes, red peppers, tomato, citrus, cantaloupe, etc), dark
vegetables (e.g. broccoli, spinach, wheat grass), red wine, tea, and dark honey. A
slightly more complete list of foods, separated into which contain vitamins C, E, and A is
in question #2 of section 8.
3. What is the “glycemic index” and why should I care?
The scientific measurement of how fast a type of food digests is called its “glycemic
index” (GI). The GI of an entire meal is the calorie-weighted average of the GI of the
foods that make up the meal. Fiber, protein, and fat slow down digestion and therefore
have a low GI. Low GI foods keep blood sugar from rising too fast. Rapidly rising blood
sugar results in a huge spike of insulin released from the pancreas. Insulin shuttles
sugar into all organs, particularly fat cells, if the calories in any meal are excessive.
Adrenalin levels at 80% VO2 max inhibits insulin release by a factor of two. This allows
a greater fraction of blood sugars to go to active muscle rather than inactive tissues (e.
g. fat). The glycemic index itself (a list of numbers relating how rapidly different foods
digest compared to each other) was initially developed for diabetics because it is
particularly important that their blood sugar levels are kept as close to normal as
possible (both during and between meals). The way to do this is eat foods that digest
slowly. While I do not recommend that anyone calculates the glycemic index of their
meals, I do recommend that refined carbohydrates (white bread, white pasta, white rice,
and sugar) be minimized except during and immediately following exercise when
adrenalin is present. High-fiber (i.e. low GI) meals will target your carbohydrate intake
to your muscles, allow you to lose weight without heavy caloric restriction, and will keep
your blood sugar normal, which will keep your energy and mental focus high. The most
important times of the day to eat low GI foods is prior to training (see question #3 in
section 3) and prior to sleeping (so that blood sugar is not low during your most
important recovery period). Eating some refined carbs may be necessary during a day
of carbohydrate loading (see question #4 of pre-exercise nutrition), but the refined
carbs should be split up into many meals so that insulin is still somewhat controlled.
Antioxidants and Fiber
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© Clyde F. Wilson