Research

Hormonal

Possession of the GLI3 rs10263647 T/T genotype prevents resistance training-induced increases in vastus lateralis muscle fiber cross-sectional area (fCSA), whereas T/C and C/C genotypes exhibit significant hypertrophy.

If you are a young man starting resistance training, your genetics (specifically the GLI3 gene) may dictate whether your muscle fibers actually increase in size. Those with the T/T genotype may not see muscle fiber growth despite training, while those with T/C or C/C genotypes will likely see significant growth. This is a biological filter, not a failure of effort.

ModerateQualifiesMEDIUM confidence
Follow-up analyses indicated that mean fCSA increases occurred in the T/C and C/C GLI3 genotypes (P < .001 and P < .001, respectively), whereas no change occurred in the T/T GLI3 genotype (P = .936).
Christopher G. Vann et al. · The FASEB Journal · 2021

Why this rating

Genome-wide association study with a relatively small sample size (n=109) and exploratory P-value thresholds.

Source

An intron variant of the GLI family zinc finger 3 (GLI3) gene differentiates resistance training‐induced muscle fiber hypertrophy in younger men

Christopher G. Vann et al. · The FASEB Journal · 2021

DOI 10.1096/fj.202100113rr

cohort · n=109Cited 6×
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DOI resolved against Crossref · corpus check 2026-06-10

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