Sarcopenia

Abstract

Sarcopenia refers to the process of age-related skeletal muscle loss.Although all humans lose muscle mass as they age, the term sarcopenia isoften used to refer to older persons with skeletal muscle values in anunhealthy range. This has traditionally been defined as aheight-adjusted muscle mass of two standard deviations or more below themean of a young and healthy population.Several cross-sectional studies published in the past decade report thatsarcopenia is strongly associated with functional impairment andphysical disability. Newer findings based on longitudinal analyses oflarge cohort studies have reported much weaker effects of sarcopenia onphysical disability risk, implying that the effects of sarcopenia onfunction and disability inferred from earlier cross-sectional studieswere overestimated.An initial strategy that may retard the normal progression of sarcopeniain older persons is to ensure that they consume adequate protein intheir diet. The average protein intake is lower in older adults eventhough they may have increased protein needs. Long-term protein-feedingstudies are required to demonstrate whether the acute benefits ofprotein supplementation on muscle protein synthesis can translate intolong-term improvements in muscle mass and strength in older persons.Physical activity, particularly resistance exercise, is the mostpromising approach for preventing and treating sarcopenia. To maximizestrength development, a resistance should be used that allows 10-15repetitions for each exercise. Older adults should perform at least oneset of repetitions for 8-10 exercises that train the major musclegroups, and exercises for each of the major muscle groups should occuron two or three non-consecutive days of the week.