Even though muscles grow bigger after weight training, the protein parts of the protein-making machines don’t increase — it’s the RNA parts that go up, meaning the cell makes more RNA, not more...
Claim Context
Resistance training does not increase ribosomal protein levels in older adults, despite inducing hypertrophy and ribosomal RNA increases, suggesting rRNA production may be the rate-limiting step in muscle growth.
“We did not find that levels of any of the ribosomal proteins increased following 4 wk of RT in any of the clusters. In fact, levels of rpS6 and rpL7a actually decreased from week 0 to week 4 (−22 and −27%, respectively, P < 0.05 for both).”
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
That supplementing ribosomal proteins does not enhance hypertrophy if rRNA synthesis is blocked.
A double-blind RCT of 100 older adults undergoing 8 weeks of resistance training, randomized to ribosomal protein supplementation (oral amino acid cocktail targeting rp synthesis) or placebo, with and without CX-5461, measuring rRNA and CSA.
Whether baseline ribosomal protein levels predict hypertrophy response.
A prospective cohort of 150 older adults measuring baseline levels of 20 ribosomal proteins via proteomics, then tracking hypertrophy over 16 weeks of resistance training.
Whether nonresponders have lower ribosomal protein levels than responders.
A case-control study comparing baseline levels of 8 ribosomal proteins in 25 extreme responders and 25 nonresponders matched for age and diet.
Whether ribosomal protein levels correlate with muscle size in older adults.
A cross-sectional analysis of 120 older adults measuring 10 ribosomal proteins and type II fiber CSA via biopsy and mass spectrometry.
Anecdotal evidence of high ribosomal protein levels in individuals with exceptional hypertrophy.
A case series of 5 older adults with >80% hypertrophy documenting ribosomal protein abundance via proteomics.