Research

Mixed

Resistance training responsiveness is highly heterogeneous, with non-responder rates ranging from 0% to 84% for muscle size, 0% to 44% for strength, and 37-42% for functional performance, indicating that individual ability to respond varies widely regardless of the intervention.

Do not assume resistance training will yield identical results for everyone. If you are not seeing expected gains in strength or size after 4-12 weeks, you may be a 'non-responder' for that specific protocol. This is common (up to 84% for muscle size in some studies). Consult a professional to adjust volume, intensity, or exercise selection rather than abandoning training entirely.

ModerateQualifiesMEDIUM confidence
Regarding the effectiveness of RT, the prevalence rate for non-responders ranged from 0% to 44% for muscle strength, from 0% to 84% for muscle size, and from 0% to 42% for functional performance, while for muscle power, the only study found showed a responsiveness rate of 37%.
Tomé Edson dos Reis Moda et al. · Sports Medicine and Health Science · 2023

Why this rating

The review includes 13 studies with 921 subjects, but only two had low risk of bias, and the evidence is described as 'incipient' and 'widely heterogeneous'.

Source

Responsiveness of functional performance and muscle strength, power, and size to resistance training: A systematic review

Tomé Edson dos Reis Moda et al. · Sports Medicine and Health Science · 2023

DOI 10.1016/j.smhs.2023.12.003

systematic_review · n=921Cited 1×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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