Which factor contributes to loss of muscle and bone strength with age?

• A. Aging process
• B. Regular resistance training
• C. Adequate nutrition
• D. Hydration

Answer: (A)

With aging there is a natural decline in both muscle mass and bone density, driven by sarcopenia and osteoporosis. Hormonal shifts (lower levels of anabolic hormones like estrogen, testosterone, and growth hormone), reduced satellite cell activity, and slower protein synthesis lead to smaller, weaker muscles. At the same time, bone remodeling slows, causing bone density to fall and fracture risk to rise. This aging process is the factor most consistently linked to loss of muscle and bone strength over time.

Regular resistance training counters this decline by stimulating muscle protein synthesis and promoting muscle maintenance or growth, while also applying mechanical load that helps preserve or increase bone density. Adequate nutrition supplies the amino acids, calcium, vitamin D, and other nutrients needed for muscle and bone maintenance. Hydration is essential for overall function but is not the primary driver of age-related muscle and bone loss.