Muscle loss starts at the age of 45 years?

At which age do we start to lose muscle mass?

Aging is associated with the loss of muscle mass. This phenomenon is also known as sarcopenia. Around what age does this start to occur?

This study investigated the influence of age on muscle mass in a large sample of adults. Skeletal muscle mass was measured with a whole-body MRI for 468 adults of 18-88 years old. People that were bedridden, had physical disabilities, and/or had chronic illnesses were excluded.

Skeletal muscle mass is stable until the mid-40s, after which a negative correlation between muscle mass and age was observed. In addition, muscle loss appeared to accelerate with increasing age.

Muscle mass loss was greater in the lower body when compared to the upper body. This may be explained by a reduction in physical activity of primarily the lower body.

A limitation of the study is that it’s cross-sectional. However, cohort or intervention research is not really feasible for this research question.

Study:
Janssen I, Skeletal muscle mass and distribution in 468 men and women aged 18-88 yr. J Appl Physiol, 2000