What is the relationship between aging and muscle mass loss? Aging is associated with deficits in the concentration of serum testosterone, growth ...

What is the relationship between aging and muscle mass loss?

Aging is associated with deficits in the concentration of serum testosterone, growth hormone, and insulin-like growth factor (IGF-1), which stimulate muscle protein synthesis.
There is a greater production of pro-inflammatory cytokines that have catabolic effects on muscle tissue.
The loss of selective fast-twitch fibers would help explain some of the characteristics of strength evolution with age, such as limitations in contraction speed, the discrepancy between muscle volume reduction and strength itself, and the preservation of muscle endurance capacity despite the decline in the ability to produce tension.
a) Only I is correct.
b) Only II is correct.
c) Only III is correct.
d) I, II, and III are correct.
e) None of the above statements are correct.