PRESERVING MOBILITY IN OLDER ADULTS

Age-related loss of strength contributes to impaired mobility and incr eases the risk of falls. Recent research has focused on 2 approaches t o preventing age-related loss of strength-promoting physical activity and exercise (especially strength training) and using trophic factors to enhance muscle performance. Epidemiologic evidence strongly support s a role of regular physical activity in successful aging by preservin g muscle performance, promoting mobility, and reducing fall risk. Rand omized controlled trials provide convincing evidence that strength and endurance training improve muscle performance in older adults. Eviden ce is rapidly accumulating from randomized trials that endurance, stre ngth, and balance training promote mobility and reduce fall risk, thou gh exercise effects differ according to the type of exercise, details of the exercise program, and the target group of older adults. Because lifetime regular physical activity is recommended for all older adult s, a reasonable strategy (especially for weak adults) is an activity p rogram that includes strength training. In contrast, insufficient evid ence exists to recommend the long-term use of trophic factors to prese rve muscular performance. An intervention that merits additional study is avoiding the use of psychoactive drugs because drugs like benzodia zepines appear to be risk factors for inactivity and may have unrecogn ized direct effects on muscular performance. Because chronic illness i s a risk factor for inactivity and disuse muscle atrophy, randomized t rials comparing strength training with other interventions would be us eful in understanding whether-strength training has advantages in pres erving muscle performance and improving health-related quality of life in a variety of chronic illnesses such as depressive illness.