Research

Mixed

Older adults (60-75 years) retain the capacity for significant myofiber hypertrophy in response to resistance training, effectively restoring type II fiber size to levels comparable to young adults, despite exhibiting smaller absolute hypertrophy gains than young men.

If you are over 60, you can still build significant muscle size with resistance training. While you might not grow as fast as a 25-year-old, your muscles will still get bigger, particularly the fast-twitch fibers responsible for power. Stick to a consistent 3-days-per-week schedule, focus on progressive overload (doing more weight or reps over time), and allow for adequate recovery, as your regenerative processes may be slower than younger individuals.

GoodQualifiesHIGH confidence
Of clinical significance, we report that, after only 16 wk of resistance training, older adults were capable of restoring the size of type II myofibers to the pretraining sizes found in adults ≥35 yr younger.
David J. Kosek et al. · Journal of Applied Physiology · 2006

Why this rating

Randomized controlled trial with clear inclusion/exclusion criteria, though sample size is moderate (n=49) and specific to untrained adults.

Source

Efficacy of 3 days/wk resistance training on myofiber hypertrophy and myogenic mechanisms in young vs. older adults

David J. Kosek et al. · Journal of Applied Physiology · 2006

DOI 10.1152/japplphysiol.01474.2005

rct · n=49Cited 504×
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DOI resolved against Crossref · corpus check 2026-06-10

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