Science builds for the benefits of L-Carnitine on aging muscle

November 04, 2008

Supplementation with L-Carnitine restores the level in muscle that was altered by natural losses that occur naturally with age, according to a new study with rats. The researchers form the University of Dijon report that supplementation with L-Carnitine improved muscle capabilities in the old animals.
According to the published results decreases in abdominal fat were also observed.
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 L-carnitine levels in the muscles were found to be 34 per cent lower in the elderly animals compared to young ones. The old rats were fed a control diet and supplemented with L-Carnitine (30 mg/kg body weight) for 12 weeks. This led to a restoration of L-Carnitine levels in muscle cells. Furthermore, a 55 per cent improvement in the oxidative capacity in the muscles of the old rats was recorded by the Dijon-based researchers.
Normal age-related increases in body weight appeared to be limited by L-Carnitine supplementation. This was possibly due to an inhibition of fat gain by increasing the level of fatty acid oxidation (fat burning). The results of the study arepublished in The Journals of Gerontology Series A: Biological Sciences and Medical Sciences
Volume 63, Pages 1027-1033

Whey protein builds muscle in the elderly

A supplement of whey protein can boost the building of muscle in the elderly, with the effects beyond that of just the amino acid content, says a new study. Fifteen elderly people took part in the trial, which found improvements in the levels of phenylalanine – a measure of muscle protein accumulation. “This finding may have practical implications for the formulation of nutritional supplements to enhance muscle anabolism in older individuals,” wrote lead author Christos Katsanos from Arizona State University.
The participants with an average age 66 received a bolus (large serving) containing whey protein (15 grams or ½ ounce), or the constituent essential amino acids from whey at 6.72 grams, or the non-essential amino acids from whey at 7.57 grams. During the 3.5 hours that followed ingestion of the bolus, the researchers measured the phenylalanine balance in the subjects.
Katsanos and his co-workers report that only subjects in the whey group experienced improvements in the phenylalanine balance. “The most important finding of this study is that WY, at least in the amount ingested in this study, results in greater anabolic effect in elderly persons than its essential amino acids,” wrote the researchers.

“Therefore, this suggests that whey ingestion improves muscle protein accretion in elderly persons through mechanisms that are beyond those associated with its EAA content.” The study is published in the October 2008 issue of the journal Nutrition Research.