Aging is accompanied by loss of muscle mass and function.  scle fibers can be replaced with fat, levels of carnosine are reduced in muscle, and there is a reduction in ability to balance (buffer) muscle acidity.  This can result in frailty, impaired balance, slow gait, and risk of falling.  This loss of muscle activity is termed sarcopenia.

Carnosine is a combination of two amino acids, histidine and beta-alanine* (BA).  It is known that supplementation with BA may increase muscle carnosine by 60-80%, with improved ability to exercise.  The reviewed study examined whether BA treatment could alter exercise performance and muscle carnosine content in elderly people.  The subjects were 18 people aged 60-80 who had not had any exercise program for one year and had no limiting diseases.  They were instructed not to exercise during the course of the study.

The participants were given either BA or placebo.  The treated group received 3.2 g BA sustained-release per day.  The subjects were studied at onset and after 12 weeks for muscle carnosine, exercise capacity, muscle function, and quality of life.  They continued to be physically inactive and well nourished.  Muscle carnosine content was evaluated by MRI (magnetic resonance imaging) scanner.

The subjects went to the laboratory twice for physical capacity testing on a motorized treadmill.  The speed of the treadmill was gradually increased to 3.5 mph and each person was verbally encouraged to exercise to exhaustion.  The time-to-exhaustion was recorded.  Muscle function was evaluated by seeing how many times a person could sit and stand up from a 45 cm chair in 30 seconds.  Also, testing evaluated how long each person took to stand, walk 3 meters, turn, return, and sit down (timed-up-and-go testing).  These times were compared to each person’s previous testing.

Quality of life was evaluated for physical functioning, limitations due to health, body pains, general health perceptions, vitality, social functioning, emotional health, and mental health.  Food intake was evaluated by individual recall on 3 separate days.  Food and beverages were listed for 24 hours each time.  Blood and urine were tested for liver, muscle, and kidney functioning and for blood cell evaluations.

Muscle carnosine content showed a significant increase in the BA group at 85.4%.  Time to exhaustion studies showed a 36.5% improvement in the BA group.  The increase in muscle carnosine testing correlated with the time-to-exhaustion studies.  No significant differences were seen between BA and placebo groups on timed-stands and timed-up-and-go testing.  Significant changes were not seen in the quality of life tests.

DISCUSSION:  Aging doesn’t impair uptake of beta-alanine or carnosine synthesis by muscles.  Loss of appetite in the elderly can reduce the intake of histidine-containing chemicals such as carnosine.  The use of sustained-release capsules lowers peak blood levels and prevents urinary loss of the beta-alanine.  Supplementation with beta-alanine may be beneficial in maintaining better carnosine levels with improved exercise capacity.

CONCLUSION:  This study demonstrates that elderly people can increase carnosine in muscle by supplementation with beta-alanine, just as in younger people.  This improves exercise tolerance with no negative effects seen.

NOTE:  *Beta-alanine is an amino acid necessary for the production of muscle carnosine.

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Rainbow Grocery sells the following products:  Carnosine.

PMID: 22143432.

Summary #794.