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Do Antioxidants Help or Hinder Your Workouts
By Paul Rogers
Antioxidants have been big news in the health supplement industry for over 30 years. Antioxidants like vitamins C and E and beta carotene (which converts to vitamin A) help mop up chemical fragments called "free radicals" that damage the DNA of cells and that also cause systemic inflammation, which is thought to be a factor in many diseases. This propensity to cause damage to the body is called "oxidative stress."
Free Radicals Essential to Metabolism
However, the production of these reactive particles, the free radicals, is an essential part of metabolism and energy production when food is digested and turned into energy through reactive mechanisms with glucose and fat and oxygen -- processes called oxidative metabolism and beta oxidation. The question arises as to whether there might not be a danger of upsetting this energy system with excessive antioxidant intake from supplements, in which individual vitamins, extracted from the complex compounds in whole foods, act differently and negatively.
A fulsome intake of antioxidants is likely to be useful in squelching excessive free radicals produced as a result of our exposure to environmental pollutants like pesticides in food or water or toxic air emissions. But, eating a healthy diet, especially fruit and vegetables and whole grains, nuts and seeds, provides plenty of dietary antioxidants. The question that arises is whether extraordinary intakes, in the form of supplements, is necessarily better, or whether they could even have adverse effects.
Vitamin Intake From Healthy Diets Is Likely Sufficient
Considering that the highest recommended intake for vitamin C per day is 120 milligrams (during breastfeeding), and less in other category recommendations, common supplement doses of 1000 milligrams and above are beyond that which would ensure compliance in the event of dietary deficiencies. An orange has about 70 milligrams. Vitamin C is an example, and this principle could well apply to other vitamin antioxidant supplements like vitamin E.
Weight Training, Exercise and Antioxidants
What's this got to do with weight training and other vigorous exercise regimens? In sports medicine studies, it's been shown that vigorous exercise produces free radicals because energy systems and metabolism are ramped up during exercise, eating to fuel exercise, and even after exercise to some degree. Antioxidant supplements were once considered useful to stem the possible damage that exercise-induced free radicals might do to muscle and other tissues -- perhaps even to prevent sore muscles in the days following exercise. In addition, benefits to immunity and general dietary compliance have been postulated.
However, other studies showed that the body adapted to the onslaught of exercise-related free radicals by increasing the body's internal, natural antioxidant defense systems -- certain enzymes -- perhaps even to a level greater than in non-exercisers. In other words, the body was adjusting to the oxidative stress of exercise and probably needed no assistance. And this adaptive response might even be a cornerstone of the health effects of exercise.
Supplementary Antioxidants, Pro-oxidants and Performance
The question of whether too high a level of antioxidant activity, as supplements, might be harmful or at least negatively affect athletic performance, and even health, is yet to be answered conclusively.
Even so, at least some studies have shown that, paradoxically, high levels of antioxidants like vitamin C might have a "pro-oxidant" effect under certain conditions.
Also, a study published in the journal Proceedings of the National Academy of Sciences in 2009, showed that even moderate supplement doses of antioxidants blocked the adaptive response of the body's natural defense systems in exercisers. The researchers found that in the group taking the vitamins there was no improvement in insulin sensitivity -- which usually occurs with exercise -- and almost no stimulation of the body’s natural defense mechanism against oxidative damage.
Summary of Antioxidants in Weight Training
Further research is required to pin down exactly how and when antioxidant supplements might be useful, if at all. If you eat poorly, with low antioxidant intake, a multivitamin supplement might bring you up to requirements. But it's worth remembering that if you exercise hard and long, and eat extra food to fuel that activity, a healthy diet is likely to supply the extra antioxidants required for such activity. Some research has suggested that the complex antioxidant effects of foods cannot be replicated by supplements in any case.
Eat healthy and eat sufficient to fuel your weight training and other exercise regimens and you shouldn't need antioxidant supplements. They may even be limiting.
Sources
Ristow M, Zarse K, Oberbach A, et al. Antioxidants prevent health-promoting effects of physical exercise in humans. Proc Natl Acad Sci USA. 2009 May 26;106(21):8665-70.
Carr A, Frei B. Does vitamin C act as a pro-oxidant under physiological conditions? The FASEB Journal. 1999;13:1007-1024.
Gomez-Cabrera MC, Domenech E, Romagnoli M, et al. Oral administration of vitamin C decreases muscle mitochondrial biogenesis and hampers training-induced adaptations in endurance performance. Am J Clin Nutr. 2008 Jan;87(1):142-9.
By Paul Rogers
Antioxidants have been big news in the health supplement industry for over 30 years. Antioxidants like vitamins C and E and beta carotene (which converts to vitamin A) help mop up chemical fragments called "free radicals" that damage the DNA of cells and that also cause systemic inflammation, which is thought to be a factor in many diseases. This propensity to cause damage to the body is called "oxidative stress."
Free Radicals Essential to Metabolism
However, the production of these reactive particles, the free radicals, is an essential part of metabolism and energy production when food is digested and turned into energy through reactive mechanisms with glucose and fat and oxygen -- processes called oxidative metabolism and beta oxidation. The question arises as to whether there might not be a danger of upsetting this energy system with excessive antioxidant intake from supplements, in which individual vitamins, extracted from the complex compounds in whole foods, act differently and negatively.
A fulsome intake of antioxidants is likely to be useful in squelching excessive free radicals produced as a result of our exposure to environmental pollutants like pesticides in food or water or toxic air emissions. But, eating a healthy diet, especially fruit and vegetables and whole grains, nuts and seeds, provides plenty of dietary antioxidants. The question that arises is whether extraordinary intakes, in the form of supplements, is necessarily better, or whether they could even have adverse effects.
Vitamin Intake From Healthy Diets Is Likely Sufficient
Considering that the highest recommended intake for vitamin C per day is 120 milligrams (during breastfeeding), and less in other category recommendations, common supplement doses of 1000 milligrams and above are beyond that which would ensure compliance in the event of dietary deficiencies. An orange has about 70 milligrams. Vitamin C is an example, and this principle could well apply to other vitamin antioxidant supplements like vitamin E.
Weight Training, Exercise and Antioxidants
What's this got to do with weight training and other vigorous exercise regimens? In sports medicine studies, it's been shown that vigorous exercise produces free radicals because energy systems and metabolism are ramped up during exercise, eating to fuel exercise, and even after exercise to some degree. Antioxidant supplements were once considered useful to stem the possible damage that exercise-induced free radicals might do to muscle and other tissues -- perhaps even to prevent sore muscles in the days following exercise. In addition, benefits to immunity and general dietary compliance have been postulated.
However, other studies showed that the body adapted to the onslaught of exercise-related free radicals by increasing the body's internal, natural antioxidant defense systems -- certain enzymes -- perhaps even to a level greater than in non-exercisers. In other words, the body was adjusting to the oxidative stress of exercise and probably needed no assistance. And this adaptive response might even be a cornerstone of the health effects of exercise.
Supplementary Antioxidants, Pro-oxidants and Performance
The question of whether too high a level of antioxidant activity, as supplements, might be harmful or at least negatively affect athletic performance, and even health, is yet to be answered conclusively.
Even so, at least some studies have shown that, paradoxically, high levels of antioxidants like vitamin C might have a "pro-oxidant" effect under certain conditions.
Also, a study published in the journal Proceedings of the National Academy of Sciences in 2009, showed that even moderate supplement doses of antioxidants blocked the adaptive response of the body's natural defense systems in exercisers. The researchers found that in the group taking the vitamins there was no improvement in insulin sensitivity -- which usually occurs with exercise -- and almost no stimulation of the body’s natural defense mechanism against oxidative damage.
Summary of Antioxidants in Weight Training
Further research is required to pin down exactly how and when antioxidant supplements might be useful, if at all. If you eat poorly, with low antioxidant intake, a multivitamin supplement might bring you up to requirements. But it's worth remembering that if you exercise hard and long, and eat extra food to fuel that activity, a healthy diet is likely to supply the extra antioxidants required for such activity. Some research has suggested that the complex antioxidant effects of foods cannot be replicated by supplements in any case.
Eat healthy and eat sufficient to fuel your weight training and other exercise regimens and you shouldn't need antioxidant supplements. They may even be limiting.
Sources
Ristow M, Zarse K, Oberbach A, et al. Antioxidants prevent health-promoting effects of physical exercise in humans. Proc Natl Acad Sci USA. 2009 May 26;106(21):8665-70.
Carr A, Frei B. Does vitamin C act as a pro-oxidant under physiological conditions? The FASEB Journal. 1999;13:1007-1024.
Gomez-Cabrera MC, Domenech E, Romagnoli M, et al. Oral administration of vitamin C decreases muscle mitochondrial biogenesis and hampers training-induced adaptations in endurance performance. Am J Clin Nutr. 2008 Jan;87(1):142-9.
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