Training: Antioxidants: What are they? Why are they important?

Excerpt from Chris Carmichael’s Food for Fitness: Eat Right to Train Right.

Written by: Chris Carmichael, Jim Rutberg, Kathy Zawadzki, CTS Certified Coach

Understanding Free Radicals

Free radicals are not a new terrorist group, but they are just as dangerous as one. Under normal conditions, most of the oxygen used by the aerobic system is reduced to form water along with energy. However, about 2-5% of available oxygen becomes converted to “free radicals” that can move freely about the cellular structures and cause damage to cell membranes, enzymes, and protein structures. They are dangerous in that their presence can create a chain reaction to produce even more of themselves. Since free radicals have been implicated in most diseases associated with aging, they should be of particular importance to the more “mature” or aging athlete.

Just as an apple slice turns brown in the presence of oxygen, certain body tissues become oxidized as well. Several conditions may contribute to increased oxidative stress, including consuming diets low in antioxidant nutrients, smoking cigarettes, living in areas with significant air pollution, or having certain diseases associated with elevated oxidative stress status, such as diabetes. Antioxidants are critically important to athletes, not necessarily because they improve performance, but because they counteract a potentially harmful side-effect of high activity levels. Although regular exercise produces many positive benefits, your high activity level as an athlete may also put you at greater risk than your sedentary counterparts for producing higher levels of cell-damaging free radicals.

Interestingly, the part of your cells that are responsible for producing energy, the mitochondria, are among the most susceptible structures to damage from free radicals, and the damage can actually impair the cell’s ability to produce new, more effective mitochondria for itself. This has been suggested as one of the primary causes of the diminished ability to produce energy associated with aging.

Antioxidants

Given that free radicals are produced during normal metabolism, it is not surprising that our bodies are equipped to manage them. Antioxidants are nutrients that may inactivate these dangerous by-products and help repair the cellular damage. They may be able to keep the damage from getting out of control in your body by (1) neutralizing free radicals, (2) minimizing the formation of new free radicals and (3) repairing the damage from oxidation.

Think of antioxidants as “traffic lights” for your cells. Traffic lights work to keep order and prevent destruction and mayhem in a maze of cars and traffic. The more “traffic” (free radicals) there is, the more traffic lights (antioxidants) you need. Several studies have shown that training enhances an athlete’s antioxidant enzyme defense system. However, you can’t take advantage of this increased capacity unless you consume more foods that contain antioxidants. The most important vitamins and minerals that may function as antioxidants in the body are Vitamin E, Vitamin C, Beta-carotene and Vitamin A, Selenium, and Zinc. By relying on a well-balanced diet with a variety of fresh fruits and vegetables, you may be able to ensure that you will be getting a good balance of these antioxidants. Take care when consuming multiple supplements than contain Vitamins A and E, as these are fat-soluble and can accumulate to toxic levels in the body.

The increased potential athletes may have for cellular damage caused by oxidative stress and free radicals should be considered a minor consequence of being a highly active individual. The benefits of training have a much greater positive impact on your health than the possible detriments caused by free radicals. All the same, consuming antioxidants may further reduce the negative effects of free radicals, and may thereby protect your long-term health. They’re just one more benefit to a diet rich in fresh fruits and vegetables.