What is the effect of weight-bearing and resistance exercise on bone density?

• A. Decreases bone density.
• B. No effect on bone density.
• C. Mechanical loading stimulates bone formation and improves balance to reduce falls.
• D. Only improves joint flexibility.

Answer: (C)

Mechanical loading from weight-bearing and resistance exercise signals bones to adapt and strengthen. When bones experience strain from lifting, walking, or resistance work, osteocytes detect the stress and stimulate osteoblasts to form new bone tissue, leading to increased bone density over time in the loaded areas. At the same time, these activities build muscle strength and coordination, which improves balance and reduces the risk of falls—an important factor in preventing fractures. So, weight-bearing and resistance exercise both stimulate bone formation and enhance balance to lessen fall risk.