L-Carnitine may boost exercise recovery and reduce muscle soreness

Daily supplements of L-Carnitine may reduce muscle soreness in middle-aged individuals and accelerate post-exercise recovery, says a new study. Two grams of L-Carnitine per day was found to have beneficial effects on muscle soreness after exercise, as well as positive effects on a range of biochemical markers like free radicals, and muscle tissue disruption, according to findings published in Metabolism. “The major finding and new discovery of the present study were that l-Carnitine supplementation can beneficially affect post-exercise markers of metabolic stress, muscle disruption, and muscle soreness in men and women older than 40 years,” report researchers from the University of Connecticut. “These findings support our previous working hypothesis that L-Carnitine supplementation in younger people can reduce chemical damage to tissues after exercise and optimize the processes of muscle tissue repair and remodelling,” they added.

     L-Carnitine, a vitamin-like nutrient, occurs naturally in the human body and is essential for turning fat into energy. It is frequently used as a dietary supplement by physically active people to help with post-exercise recovery. Extensive scientific research shows the supplement promotes cardiovascular health and that other studies suggest the nutrient may be useful in weight management.

     The new study sought to expand previous findings that L-Carnitine supplements may improve recovery in younger subjects. Led by Professor William Kraemer, the researchers recruited 18 men and women with an average age of 48.7 and normal activity levels to participate in their double-blind, placebo-controlled, crossover study. Participants received either L-Carnitine (2 grams per day) or placebo for 24 days. This was followed by a one-week washout period and then crossing over to the other intervention. After 21 days of each intervention the participants performed resistance exercise (squat/ leg presses).

     Blood samples showed that L-Carnitine supplementation significantly improved a range of biochemical markers, including purine metabolism, free radical formation, and muscle tissue disruption. “The L-Carnitine l-tartrate supplementation therefore reduced both myoglobin and creatine kinase concentrations providing additional evidence that LCLT reduces post-exercise muscle disruption,” wrote the researchers. “Such findings support the additional findings that L-Carnitine l-tartrate significantly reduced muscle soreness immediately after the exercise workout and at 24 and 48 hours post exercise when compared with the placebo condition.” The study is published in the current issue of the journal Metabolism - Clinical and Experimental.