Leucine-Enriched Amino Acid Mixture May Protect Against Muscle Damage
Repeated performance of high-force muscle contractions or unaccustomed exercise can result in tissue damage in the muscles. A new study has found that a leucine-enriched amino acid (LEAA) supplement may help protect against muscle damage and improve muscle recovery.
Participants in the study included 10 untrained men with an average age of 23. They took 3.6 grams of the LEAA supplement or a placebo three times daily for eight days. This was followed by a three-week washout period, after which the participants switched interventions.
The participants repeatedly flexed and extended their elbows for 5 sets, consisting of 10 counts per set, at full power while using a dynamometer. The researchers evaluated changes in serum creatine phosphokinase activity and myoglobin concentration as markers of muscle tissue damage prior to and after exercise and on days 1, 2, 3, 5, and 7. They also evaluated muscle recovery by measurements of maximal muscle strength, blood test and muscle soreness over the 7 days following the exercise.
The researchers found that while serum creatine phosphokinase activity increased in both groups, the increase was significantly lower in the supplement group, which suggests less muscle damage and faster recovery. No significant differences were seen in myoglobin concentration or self-reported muscle soreness between the two groups.
The study was conducted by researchers from Tsukuba University of Technology, the University of Tsukuba, and Hokkaido Nippon-Ham Fighters. It was published on January 10, 2019 in the Journal of Physical Therapy Science.