Balancing benefits and risks of aerobic exercise for aging and musculoskeletal health.

BACKGROUND

Long-term exercise is recognized as one of the most effective means of maintaining health after aging, but the relationship between moderate exercise and health in the older population is often overlooked.

OBJECTIVE

The present study was conducted to investigate the effects of excessive endurance exercise on the old mice musculoskeletal system.

RESULTS

The 8 weeks of normal endurance exercise significantly improved skeletal muscle mitochondrial biogenesis and increased femoral osteogenesis in young and old mice. However, the continued accumulation of total exercise volume as the exercise cycle was prolonged resulted in the younger and older mice exhibiting different exercise effects. After 8-16 weeks of moderate-intensity endurance exercise, young mice showed consistent effects of increased mitochondrial biogenesis in skeletal muscle. However, after 12-16 weeks of moderate-intensity endurance exercise, the original effects of exercise-induced mitochondrial biosynthesis were instead impaired in older mice. After 16 weeks of exercise, the aged mice showed a produces consumptive weight loss, an increase inflammation level in adipose tissue, and a decrease in femoral bone mineral density. Interestingly, with an increase in total exercise, the level of skeletal muscle inflammation in old mice did not increase significantly, while a longer exercise cycle reduced the level of skeletal muscle apoptosis, thereby maintaining the state of skeletal muscle.

CONCLUSIONS

Appropriate moderate-intensity endurance exercise has a significant gain in maintaining musculoskeletal health in aged mice. However, excessive endurance impairs the health of the musculoskeletal system in aged mice.