Some people seem to add muscle almost immediately after starting a strength program, while others move more slowly. According to the report, that difference is real: when people follow the same resistance-training plan, the results can vary widely. Experts say genetics play a major role, but training and nutrition still matter a great deal.
Genetics can influence body type, metabolism, recovery speed, and how the body responds to exercise and muscle-repair signals. One of the biggest factors is muscle-fiber makeup. Fast-twitch fibers are better suited to powerful, explosive work and may have more potential for growth, while slow-twitch fibers are more endurance-oriented. That means some people may gain size and strength faster than others, even on similar programs. Still, the report notes that training can modestly affect muscle-fiber profile over time, and there is no simple practical way to know an exact fiber breakdown without a muscle biopsy.
What else affects muscle growth?
Age is another factor. Younger adults, typically those under their mid-30s, often recover more quickly and may build strength and muscle faster because their bodies can handle training stress and repair tissue more efficiently. Older adults can still make strong progress, but they may need more recovery time between sessions. Training experience also matters: beginners often see quicker gains early on because their bodies are adapting to a new stimulus, a phase often called “newbie gains.”
Even with these differences, the report emphasizes that muscle growth is possible for everyone. As one expert put it, genetics help define the range of potential, but training and nutrition determine where someone lands within it. Building muscle is also presented as an important long-term investment, since it supports joint stability, balance, posture, injury protection, and the ability to stay active with age.
Source: womenshealthmag.com
