Radicals Affect Performance!

By Mike Adams CSCS

I hope the title of the article captured you attention. I’m not making light of the current world situation, but sometimes a little humor can help. Let me tell you though, when it comes to free radicals and our body I am very serious. I am involved in the fitness/wellness industry and have had the pleasure and honor to be associated with some of the world’s best strength and conditioning coaches like Ian King (www.kingsports.net ). The subject of athletic performance and nutritional supplementation along with the free-radical/antioxidant debate has been a focal point for research for some time. The following article is based on published studies, scientific research and self-observation. At times the information will become a bit "scientific" so get some NoDoz and a highlighter for that "special" information. With out further ado here we go …

I have paid particularly close attention to research as it relates to athletes and athletic performance. Why? Because during a training session or competitive event, the athlete’s oxygen uptake (VO2) increases, resulting in an increase in free-radical production (2, 3, 8). Due to this increase athletes may have increased their antioxidant requirements in comparison with their sedentary counterparts. In a recent study an increase in free-radical production was exhibited after aerobic and weight training (25, 27, 33-35).


Free Radicals … I thought they were only in foreign countries

Free radicals are produced when the body processes oxygen. As the body processes the oxygen, approximately 2-4% of it results in the generation of oxygen-free radicals (11, 19, 22). Free radicals could be thought of as violent lightning bolts that have the ability to rip through the cells, destroying everything in their path. The body does have its own natural defense to counteract oxidative damage to cells (2, 23, 31), but whether these naturally produced antioxidants are enough for the weekend to elite athlete is debatable (8, 21, 34). One of the crucial ironies for athletes is that their high VO2, which is a necessity for aerobic energy production, also forms substances that can potentially harm human tissue (8, 23). So where does this leave the athlete and what can be done about free radical damage?


Antioxidants are the solution!

The answer lies in antioxidants. An antioxidant is any substance that helps to reduce the severity of oxygen stress by either forming a lesser active radical or by quenching the damaging free-radical chain reaction (13). Generally, the core group of antioxidant vitamins works in tandem to stop the chain reaction by contributing electrons to free-radical molecules (1, 8, 17, 41). Importantly though, dietary antioxidants may be able to detoxify the free radicals produced during exercise, which otherwise could result in lipid peroxidation (8). These antioxidants are not supplied by the body, and need to be constantly replenished through diet and supplementation. When we exercise, our body can process up to 30 times more oxygen because of deep breathing and increased metabolism (1, 3, 7, 11). Although exercise training increases the production of the principle antioxidant enzymes (2, 16, 24, 27, 29, 31, 34, 36, 41), exercise seem to perturb the fine balance of the body’s defense systems, rendering the tissue more susceptible to damage (4, 6, 8, 26, 34, 37). In addition, critical tissues, such as the heart, possess lower levels of the protective antioxidant enzymes than do others, leaving them more susceptible to free-radical damage (8).

Unfortunately, many of us are not receiving enough vitamins and minerals from the food we eat. The food consumed today, in many cases, does not consist of the same quantities of nutrients that existed 30, 40 and 50 years ago (14, 32). Nutrients from food are lost because of many agricultural issues, including soil degradation, ripening, storing, drying, cooking, freezing, blanching, pasteurization, hydrogenation, ultra-filtration, hormone injection and a myriad of other "modern" food processing procedures (14, 32) (but at least we’ll be well preserved when we die). Importantly, many of the vitamins and minerals that are lost during these procedures and processes are required by the body to maintain our antioxidant enzyme levels (19).


The Essential Building Blocks of Antioxidants

Vitamin E: A fat-soluble vitamin, made up of several compounds known as tocopherols, has been called the most important antioxidant because of its association with the cell membrane. Vitamin E is important in energy production as it ensures that glucose is fully oxidized and that adenosine triphosphate (ATP) is generated most efficiently (33). Because vitamin E is fat-soluble, athletes on a low-fat diet may benefit from the use of vitamin E (22). It is important to note that of all the eight natural forms of vitamin E D-alpha tocopherol is shown to have the greatest nutritional and biological value, in large part due to its preferential retention by the body (43, 44)

Endurance training, in addition to increasing the oxidative capacity of muscles, improves the body’s enzymatic antioxidant defense (2, 4, 5, 8, 17, 23, 31). However, muscle and other tissues consume vitamin E during increased physical activity (3,4). Therefore, supplementation of vitamin E may be warranted to prevent free-radical damage induced by exercise (3, 8, 26, 33).



Vitamin C (a.k.a ascorbic acid): Plays two important roles in the body. The first, it is a cofactor for eight enzyme systems involved in the various functions including collagen synthesis, ATP synthesis in mitochondria, and hormone biosynthesis (36). As if that’s not enough vitamin C is also a water-soluble vitamin that plays a role in iron absorption, wound healing and in keeping gums and teeth healthy (20). It is thought to play a role in reducing the risk of certain cancers and heart disease (12). Although performance may not be enhanced by vitamin supplementation in healthy athletes and individuals, it has recently been demonstrated that untrained, or vitamin C-depleted individuals exhibit reduced work efficiency and performance during sub-maximal exercise (20). In addition, vitamin C has been shown to be the most important antioxidant in extra-cellular fluid (8, 30). Various studies have demonstrated the positive effects of vitamin C (1, 20, 30), specifically Peters (30) showed that runners supplementing with 600 mg of vitamin C daily for 3 weeks prior to the South African Comrades Marathon (90-km running race) reduced the incidence of post-race upper-respiratory tract infection by more then 50%. The study concluded that athletes in heavy training and during competitive in exhaustive endurance events have a greater vitamin C requirements than others.

When supplementing with vitamin C it is important to note that the levels of ascorbic acid in the blood reach a peak in about 2 –3 hours after ingestion then decreases as the body, in the form of urine and perspiration, eliminates it. Most of the substance is out of the body in 3 –4 hours. Due to the short duration the body, it is recommend that vitamin C supplements be taken several times throughout the day (45, 46) and that they utilize a documented slower absorption formula.

Beta-carotene: The role of beta-carotene lies in the detoxification of highly energetic free radical, singlet oxygen (O2) (21, 48). Beta-carotene is converted into vitamin A when the body is lacking the fat-soluble vitamin (8). Beta-carotene acts in tandem with vitamin E and vitamin C by boosting their antioxidant properties, and this combination may actually dissuade the development of certain cancers (9, 15, 40). In a study, Sumida et al. (38) investigates the effects of acute exhaustive bicycle exercise on antioxidant status after 30 mg of beta-carotene supplementation on healthy men. Results showed that baseline plasma beta-carotene concentration was 17 times higher after supplementation, suggesting that beta-carotene may contribute to the protection of the increasing oxidative stress during exercise.



I’m So Confused!

Hold on, this will all come together at the end … let’s continue. Although the increased training status of an athlete appears to up regulate his/her body’s endogenous antioxidant defense system (2, 4, 5, 8, 17, 23, 31), significant free-radical damage exists after exercising (5, 8, 10, 18, 19, 21). The good news is that free-radical damage is attenuated following vitamin antioxidant supplementation programs (3, 8, 26, 30, 33, 35). Even though athletes will tend to have an increased caloric intake, depending upon their sport and routine, a great deal of the "recovery" phase utilizes beverage programs that contain refined sugar.

So the main concern for antioxidant supplementation is a supply and demand issue. Is the athlete not obtaining enough antioxidant vitamins through their diet, or does the athlete possess an augmented antioxidant vitamin turnover due to an increase in metabolism? With this as a central issue, athletes that are perhaps most susceptible to free-radical damage are those on restricted diets. Endurance athletes on restricted diets, perhaps wishing to reduce weight prior to an event, may be at the most risk of free-radical/antioxidant imbalance. Long distance runners have another concern for free-radical damage. Not only do runners utilize a large VO2 throughout training and competition, but also the physical pounding during running destroys red blood cells (26). In addition, athletes on high carbohydrate (low fat) diets (such as many runners) may create an antioxidant supply problem, vitamin E being a fat-soluble vitamin (32, 42). Thus long distance runners appear to have the greatest need for vitamin antioxidant supplementation.

Two other concerns that have been discussed recently concerns the ‘weekend athlete" and the "aging" athlete (7, 18). It has been previously speculated that the weekend, or even the recreationally trained, athlete may not have a well-enough developed antioxidant defense system produced through continued training in comparison to the highly trained athlete. Hence the weekend athlete may be more susceptible to oxidative stress during hard exercises (7). It has also been speculated that the delicate balance between free radicals and antioxidant during exercise may be altered with aging (18), suggesting that supplementation of nutritional antioxidants maybe desirable.


What Should I Take?

With so many nutritional companies and supplements on the market, choosing the correct one can be overwhelming. But here is something to keep in mind when selecting a company/brand supplement. Poor manufacturing can destroy great science, so for this reason select a company that manufactures its own product line. A little known fact is that the majority of nutritional and supplement companies outsource their products to just a handful of manufacturers. In essence one manufacturing company can produce numerous "brands" of product. Look for a company that meets Good Manufacturing Practices (GMP). Most manufacturers utilize the FDA guidelines, which by the way are the same for food. GMP produced supplements are pharmaceutical-grade products, which are a much higher quality than what law (FDA) requires, thus, eclipsing the standards followed by most nutritional product manufacturers. To adhere to these exacting GMP standards a company should test the raw ingredients, test the product during manufacturing, and test everything once again before it goes out the door.

In addition to the GMP the vitamin and mineral supplements should be formulated to meet USP standards for potency, uniformity, disintegration, and dissolution. Finally the company should provide100% money back guarantee and provide some sort of technical support. Hey, we’re talking about your body, your health your performance; you wouldn’t want to deal with just any company would you?


In Conclusion….

The sum objective of all antioxidants is to reduce the long-term damage that oxidative exercise might do to exercising muscle (28). With this in mind, antioxidants should be seen as maintaining or improving the health of the athlete as he/she ages. Also, for optimal athletic health, considering the questionable state of our food, water and environment, and the previously stated increased nutritional needs to any athlete, the evidence is overwhelmingly convincing to include a program of nutritional/antioxidant supplementation with a proper balanced diet … and maybe a glass of wine here and there.

If you have any comments or questions, or if you would like to receive a special free report "Your Health is in Danger" send an e-mail to mikeadams69@hotmail.com


Mike Adams CSCS

Physical preparation Consultant

Exercise & Health Consultants

+44 (0) 1732 366711



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