CYCLING PERFORMANCE TIPS
An antioxidant, as the name suggests, can neutralize free radicals before they interact with living tissue, detoxifying them with the formation of water and oxygen. The vitamins (C, E, and beta carotene) are common antioxidants in our diet.
Although the discussion of antioxidants is usually focused on cardiovascular health, it has been suggested that free radicals may contribute to a slow recovery after tough workouts, thus antioxidants may speed up recovery. Many sports drinks tout their antioxidant content.
Studies on free radicals in exercise suggest that although exercise does increase the rate of lipid peroxidation (presumably the result of an increase in the formation of free radicals), there is a parallel increase in the natural antioxidant activity in the blood. And with regular training, our natural antioxidant defense system increases even further. There is little data as to which has the upper hand in this balancing act - the free radicals or the defenses. It has been suggested that "weekend warriors" who do not have a regular training program, might be more susceptible to free radical damage.
ANTIOXIDANTS AND PERFORMANCE
Numerous studies have produced conflicting results.
One suggested that the use of antioxidants in the form of vitamins C, E, and beta carotene decreased muscle damage in a group of runners as compared to a control group. The only controlled studies were with 600 IU of vit E for 2 days before exercise (no effect) and a second with 3 grams of vit C per day for 3 days before and 4 days after an exercise bout (reduced soreness). However, none have suggested a beneficial effect of any of the antioxidant vitamins on actual exercise performance or the rate of post-exercise recovery in athletes maintaining a balanced diet.
There is considerable speculation on the long term benefits of antioxidants in general. A study of nurses and male professionals published in 1993 demonstrated a lower rate of heart disease in those taking Vit E supplements. And a study from China indicated that the use of a multivitamin, containing antioxidants among other things, lowered the cancer death rate by 13%. However a more recent study (1996) indicated the opposite, that patients at risk for lung cancer had a HIGHER cancer rate if they took beta carotene supplements, and the study was terminated early because of those results.
How about antioxidants in cardiovascular disease - an area where there has been considerable interest and research? The most recent study demonstrated no benefit of antioxidants over placebo in blunting the effect of atherosclerosis, and indeed even suggested some harm in that antioxidants appeared to blunt the effectiveness of a proven therapy (simvastatin-niacin). As an aside, there has been interest in the benefits of other vitamins (B vitamins and folate) in the treatment of coronary artery disease - via their effect on homocysteine metabolism. The evidence is strong enough that one of my cardiology partners routinely puts his post angioplasty patients on a multivitamin plus an additional 400 mcg of folic acid and 50 mg of vitamin B6.
The bottom line is that there is little to suggest a short term performance benefit from the use of antioxidants in the competitive athlete. And plenty of controversy as to any additional long term health benefits. Although there is no evidence that they will do you any harm in the usual doses, mega-doses have been reported to have side effects and may actually decrease optimum physical performance.
In 2014, a review of antioxidants suggested that free radicals were important as a cell signalling mechanism, involved in promoting muscle health. And a paper in 2015, investigating the mechanism by which interval training improved performance, concluded "...(these changes) did not occur in muscles exposed to antioxidant, which offers an explanation for why antioxidants blunt effects of endurance training."
And recently the following article suggested that not only do the benefits of reservatol (an antioxidant) NOT translate from an animal model to humans, but it actually appears to have a detrimental effect on aerobic training.
So we have very little evidence to support a health or performance benefit with antioxidant supplements, and a suggestion that they may actually have a negative impact on performance improvement.
My take away? As there is general agreement on the health benefits of fruits and vegetables, which contain not only vitamins and antioxidants, but also other healthful micronutrients, and no proof that antioxidant supplements are of any health benefit, increasing the fruits and vegetables in our diet seems to be the best approach.
Following is a list of a few natural sources of antioxidants:
Physical trauma and micro tears are the likely explanation for post exercise muscle pain. But free radicals (oxidative stress) have been suggested as a contributing factor. If so, it makes sense that antioxidants could be a possible treatment. This is an interesting blog (well referenced although I could only read the abstracts and not the complete articles), that suggests you might be able to speed recovery by modifying your diet to increase natural antioxidants and reducing exercise related oxidative injury.
It sounds logical. But we now have what I feel is a more powerful study, a meta-analysis of 50 studies. Although there was a small benefit (less muscle discomfort) from antioxidants, it didn't seem to be enough to justify the hassles of a dietary change (just for the DOMS effect).
Eating fruits and vegetables is definitely a plus for your overall health, and there may be other performance benefits from a vegetarian leaning diet (beyond the antioxidant content) via our microbiome. But antioxidant supplements? I'd avoid wasting my money.
If you want to increase your natural antioxidant intake "just in case", studies show benefits from