Carnitine Protects the Body From Intense Exercise

After completing a fourteen-kilometer run, subjects who took carnitine fared much better than those who did not.

Carnitine, a naturally-occurring chemical compound found in the human body, has come under some scrutiny lately. While some dubious claims have been made about it being unhealthy, other research has demonstrated positive effects on health. In a recent study in the Asian Journal of Sports Medicine, researchers may have found yet another benefit.

Carnitine is known to play a major role in the utilization of fat for fuel. As such, supplemental carnitine is sometimes thought to improve performance in sports requiring a large aerobic component. Carnitine might also be beneficial for people who are in the process of losing weight.

Study Design

In the study, 21 active men were divided into two groups. One group supplemented two grams of carnitine every day for two weeks. The other group took a convincing facsimile for the same amount of time. At the end of the two weeks they ran fourteen kilometers (a little over 8.6 miles). Blood was drawn before supplementation, just before the workout, shortly after the workout, and then again a day later.

The researchers were looking for three primary things in the blood test results:

  • Antioxidant status
  • Oxidative stress to lipids by free radicals
  • Muscle tissue damage

Oxidative stress and muscle tissue damage are the results of physical stress. Antioxidant status is one of the body’s indicators that it is dealing with stress. The researchers wanted to know if carnitine consumption affected these factors.


Two weeks of carnitine consumption was an effective protocol. The day after the workout, free radical status and muscle damage were significantly lower in the group taking carnitine than in the placebo group. Antioxidants were also higher in the carnitine group, both before and after exercise and on the day after the workout. These results indicate that carnitine supplementation may assist in recovery from workouts and reduce the chance of overtraining.

Supplements vs. Food Sources

In this study, carnitine was investigated in supplement form. However, it is believed that the body might absorb food-sourced carnitine more easily. Although food sources tend to contain less carnitine than a supplement, the higher absorption may make it a more effective source. If so, then foods high in carnitine, like red meat, might be an even better option.

The body can synthesize carnitine, which means it is not a nutritionally essential nutrient, so you might have heard that supplementing with carnitine is not necessary. However, for people who exercise a lot, the body’s ability to synthesize carnitine may be taxed. This is particularly true for people who do a lot of aerobic exercise or those who are trying to lose weight. As such, consuming L-carnitine, either in supplemental form or in red meat, might assist your goals.

Either way, carnitine has proven to be a valuable nutrient for athletes. One way or another, ensure that you are getting adequate quantities. A dose of two grams per day was used in this study. Although this is well above the amount you would get from your diet, it may be needed due to low absorption. Getting a quarter of that via diet should be more than adequate.


1. Khadijeh Parandak, et. al., “The Effect of Two-Week L-Carnitine Supplementation on Exercise –Induced Oxidative Stress and Muscle Damage,” Asian Journal of Sports Medicine, 5:2, 2014

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