This newsletter highlights the importance of strength training in keeping older adults healthy and fit, explaining how it can forestall declines in strength and muscle mass, along with their attendant negative impact upon other metabolic functions and activities of daily living. Physical inactivity is common throughout the nation. Approximately 11 percent of cases of heart failure in men and 14 percent in women are attributable to obesity alone. More than half of adults over age 45 years are inadequately active. Injuries to seniors are costly to the health care system and often have serious consequences for the seniors themselves. Aging is associated with marked alterations in body composition and joint structure. Research indicates that regular joint loading and motion are necessary to maintain articular cartilage function and synovial joint range of motion. There is growing recognition of the importance of strength training for all adults in light of the loss of muscle mass in midlife due to sedentary lifestyles. There is no age limit to the benefits of exercise, and regular activity can often slow or reverse the decreased mobility that contributes to disease and disability in old age. Research shows that regular physical activity can reduce the risk of subsequent depression in older adults. Overall, regular enjoyable exercise is the most significant route to better health. (SM)