Supplementation Helps Replenish L-carnitine in Aging Muscles
Lee Swanson Research Update
Supplementation with L-carnitine may restore natural losses of the nutrient in muscles that occur naturally with age, according to researchers at the Universite de Bourgogne in Dijon, France.
In their study, researchers stated: "In mammals, during the aging process, an atrophy of the muscle fibers, an increase in body fat mass and a decrease in skeletal muscle oxidative capacities occur. Compounds and activities that interact with lipid oxidative metabolism may be useful in limiting damages that occur in aging muscle. In this study, we evaluated the effect of L-carnitine and physical exercise on several parameters related to muscle physiology."
They reported that supplementation with L-carnitine led to increases in the levels of L-carnitine in rat muscle cells, as well as improving muscle capabilities in the old animals. 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.
In the study, the L-carnitine levels in the muscles of elderly rats were found to be 34% lower than in young rats. Old rats were fed a control diet and supplemented with L-carnitine (30 mg/kg body weight) for 12 weeks. Researchers report that this led to a restoration of L-carnitine levels in muscle cells. Furthermore, a 55% improvement in the oxidative capacity in the muscles of the old rats was recorded by the researchers. Normal age-related increases in body weight appeared to be limited by L-carnitine supplementation. This was suggested to be a result of the limiting of fat gain by increasing fatty acid oxidation. Researchers also said: "Moderate physical exercise was also effective in limiting fat mass gain and inducing an increase in the capacities of the soleus to oxidize fatty acids."
The Journals of Gerontology Series A 63:1027-1033, 2008