Saturday, February 19, 2011


The use of dietary antioxidant supplements, such as vitamins C, E and others in relation to exercise is controversial. Such antioxidants are suggested because exercise is known to induce a rise in the production of oxygen metabolism byproducts, such as free radicals. Free radicals are unpaired electrons that seek out and combine with paired electrons,which is damaging to cell integrity, particularly cellular membranes. Antioxidants are thought to short-circuit the damaging effects of free radicals on cells. Exercise itself promotes the release of built-in antioxidants in the body. Moreover, more recent research shows that free radicals may not be as bad as originally surmised. In fact, free radicals may be important for exercise recovery. But this only applies to moderate exercise. When the intensity level of exercise rises, the production of free radicals can overwhelm the body’s capacity to deal with them. Excess free radicals are not only asociated with a higher level of muscle damage following exercise, but also are linked to such diseases as cardiovascular disease and cancer.

While dietary antioxidants may help prevent oxidative-related maladies, their use in exercise has shown mixed results. Some studies show beneficial effects, others don’t. Some of the most potent natural antioxidants aren’t commonly used in food supplement form, but can exert potent protective effects. One such natural antioxidant is called sulforaphane (SF). SF is found naturally in cruciferous vegetables, such as broccoli, Brussels sprouts, and others. Various studies show that it provides potent protection against the onset of several types of cancer, includng breast and prostate cancers. It does this through two mechanisms. The first involves an induction of the primary detoxifying enzyme system in the liver, known as phase-2 enzymes. This system renders  ingested carcinogens harmless,and allows the carcinogens to be excreted from the body before causing cellular damage. The other mechanism of SF involves an indirect activation of the body’s built-in antioxidant systems.

This effect of SF on antioxidant activity led to a study in which rats ran on a treadmill to exhaustion. Some of the rats in the study were provided with a high concentration of SF three days prior to exercise. When not provided with SF, the exercising rats showed high levels of muscle damage, as indicated by increased levels of enzymes associated with high level muscle damage. The rats also showed higher levels of indicators of excess oxidative damage, thus showing that the intense exercise exceeded the capacity to deal with excess free radical production that resulted from the exercise. But when provided with SF, both forms of damage decreased significantly. The rats also showed increased phase-2 enzyme activity, which led to increased overall antioxidant activity, thus explaining the protection offered by SF.One problem with this study is that the subjects were rats, not humans. But SF is known to induce the same beneficial effects in humans that it did for the rats in this study. The other problem is that the rats were provided with levels of SF that would be difficult to obtain from food alone.On the other hand, I ingest a concentrated broccoli extract supplement that contains the equivalent of 6 ounces of broccoli (in relation to SF content) in one pill. I take two pills a day, which means I’m getting the same amount of SF that is found in 12 ounces of broccoli. Eating broccoli or some other cruciferous vegetable, such as Brussels sprouts, cabbage, radishes, cauliflower, or others each day should provide enough SF to offer protective effects.

Malguti, M. et al. Sulforaphane treatment protects skeletal muscle against damage induced by exhaustive exercise in rats.J Appl Physiol 2009;107:1028-36.

What are the food supplements and foods that will really aid bodybuilding progress? Find out in my e-book, Natural Anabolics, available at

©,2013 Jerry Brainum. Any reprinting in any type of media, including electronic and foreign is expressly prohibited.

Please consider joining this blog by clicking on the blue "join this site" button to the right of this blog. This will ensure that new blogs continue to be published. It costs nothing, and takes only a few seconds. Thank you.

See Jerry's book at