[Association of daily physical performance with muscle volume and strength]

Sarcopenia disturbs the daily life of elderly people, and hinders healthy aging. We studied the association of daily physical performance with muscle volume and muscle strength in a randomly selected community-living population.

Grip power and leg muscle strength decreased about 1% per year after age 40 in both men and women. Muscle strength was greater in men than in women at every age by decade, and muscle strength in men in their 80s was similar to that in women in their 40s. Therefore, the effect of a decrease in muscle strength on daily physical performance was greater in women than men. On the other hand, the muscle volume of all limbs decreased with age in men, but there was almost no decrease in muscle volume in women. These results indicate that qualitative change in muscle was more significant than quantitative change in muscle in women. Daily physical performance was influenced by muscle performance and could be assessed based on grip power and walking speed. To prevent frailty, it may be important to determine the high-risk group for frailty using these assessments.