Why are leg workouts beneficial for health?

The presence of well-developed leg muscles, especially large muscles — quadriceps, glutes, and hamstrings — has a pronounced effect on the secretion of growth hormone (somatotropin).

Muscle Mass and Endocrine Response

The greater the muscle mass involved in work, the higher the metabolic stress:

• blood circulation is enhanced;
• the tissues' demand for oxygen and nutrients increases;
• the levels of lactate and hydrogen ions in the blood rise.

Lactate — is one of the key stimuli for the pituitary gland. Its increase after heavy leg exercises triggers a powerful release of growth hormone.

Therefore, workouts that include squats, deadlifts, lunges, and other compound movements are considered the best stimulators of somatotropin.

Neuroendocrine Connection

Under high load on large muscles, the sympathetic nervous system is activated. This causes the release of catecholamines (adrenaline and noradrenaline). They, in turn, enhance the signal to the pituitary gland for the secretion of growth hormone and stimulate lipolysis (fat breakdown).

Influence on Other Hormones

Heavy leg exercises not only directly stimulate somatotropin but also:

• increase testosterone levels;
• enhance tissue sensitivity to insulin;
• activate the release of IGF-1 (insulin-like growth factor), which mediates the anabolic effects of growth hormone in muscles and bones.

Influence of Large Muscles Outside of Workouts

Even outside of workouts, developed musculature acts as an “endocrine organ”:

• muscles secrete myokines — signaling proteins (such as irisin) that enhance metabolism, affect adipose tissue, and stimulate the pituitary gland;
• a higher overall metabolic rate is maintained, which requires more active hormonal control from the body.

Large leg muscles not only create conditions for increased growth hormone secretion during workouts but also on their own, as they increase the overall metabolic rate, stimulate the production of myokines, and provoke a powerful neuroendocrine response under any load.