Why does my friend build muscle faster on the same workout?
Same gym, same plan, very different gains.
Same gym, same plan, very different gains.
Your friend may build muscle faster because of genes like ACTN3, which favours fast-twitch power fibres, ACE, linked to strength versus endurance, and PPARGC1A, which shapes how muscles respond to training, so identical workouts produce different gains across people.
Muscle growth depends partly on the fibres you were born with. The ACTN3 gene affects fast-twitch muscle fibres used for power and explosive strength; one common variant leaves some people without functional alpha-actinin-3, which is associated with endurance leaning rather than raw power. The ACE gene is linked to whether you tilt towards strength or stamina. PPARGC1A influences how efficiently muscles build new mitochondria and adapt to training. Different combinations mean two people on the same programme respond at different speeds.
These variants are spread across all populations, including South Asians, though large training-genetics studies have historically under-sampled Indian groups, so the exact numbers for our communities are still thin. What is clear is that response to resistance training varies widely between individuals regardless of effort. Some people are high responders who gain quickly; others are slower responders who still progress, just on a longer timeline.
The takeaway: genes set your starting slope, not your ceiling. Consistency, progressive overload, enough protein, and recovery sleep close most of the gap over months. If you are a slower responder, the answer is patience and smart programming, not quitting. Comparing your week to your friend's is the wrong measure; comparing your lifts today to three months ago is the right one.
Genetic tests for ACTN3 and ACE give clues, but tracking your own strength and size over a few months is a more reliable real-world answer.
No. The common ACTN3 variant tilts you toward endurance, but plenty of people with it build real strength with consistent resistance training.
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