The aging of bone and muscle

Area of Science:

• Gerontology and Exercise Physiology
• Skeletal Muscle Biology
• Bone Physiology

Background:

• Aging is associated with significant declines in muscle and bone function.
• Distinguishing between age-related changes and those due to functional disuse is crucial for understanding these processes.

Purpose of the Study:

• To review and summarize the literature on age-associated changes in muscle and bone function.
• To highlight the role of exercise in counteracting these changes.

Main Methods:

• Literature review and synthesis of existing research on aging, muscle function, bone density, and exercise interventions.

Main Results:

• Aging reduces muscle size and strength due to fiber loss and motor unit decline, though metabolic potential remains largely intact.
• Bone loss begins in early adulthood, with distinct patterns for cortical and trabecular bone.
• Exercise training promotes muscle hypertrophy, increases strength, and can attenuate bone loss, potentially increasing bone density.

Conclusions:

• Functional disuse plays a significant role in muscle decline attributed to aging.
• Exercise interventions are effective in improving muscle function and bone health in aging individuals.
• Further research may clarify the selective loss of fast-twitch muscle fibers with aging.