Use it or Lose it! Is Weakening Musculature a Result of Aging or Muscle Disuse?

Nadège Chéry, PhD

If physical appearance owes its beauty to strong, shapely muscles, it is a rather short-lived feature of human charm, as nice biceps, sculpted thighs and other graceful or bulging aspects of our musculature eventually wither as we age. Far more than our attractive physique is altered, unfortunately, since with advancing age the loss of muscle strength and mass also greatly contributes to frailty (resulting in falls and fractures).1 Nevertheless, this undeniable consequence of the aging process is not entirely unavoidable. Indeed, simple, effective strategies that can significantly slow (or perhaps reverse) the age-related decline in muscular performance exist, yet they are often overlooked (or even feared) by the elderly.

In an individual between 30 and 80 years of age, muscle, the largest tissue of the human body,1 undergoes important decreases (up to 40%) in both strength and mass.10 This age-related loss of muscle strength and mass is typically referred to as "sarcopenia".3,9,10 The expression "muscle wasting" is also used in geriatric medicine in reference to unintentional loss of weight, when fat mass and fat-free mass decrease, as occurs following starvation (at any age) or in geriatric failure to thrive.7,8

The extent of the loss of strength is not the same across different types of muscles, and also varies greatly among individuals.