When the study says there’s a 100% chance volume helps, it doesn’t mean it definitely causes gains — it just means the data strongly suggest there’s a link, not that one thing makes the other happen.
Scientific Claim
The use of posterior probability (e.g., 100%) in this meta-regression indicates the likelihood that the true effect of volume or frequency exceeds zero, not proof of a causal relationship, and should be interpreted as probabilistic evidence of association.
Original Statement
“The posterior probability of the marginal slope exceeding zero for the effect of volume on both hypertrophy and strength was 100%, indicating that gains in muscle size and strength increase as volume increases.”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The claim accurately describes the meaning of posterior probability in Bayesian analysis and correctly links it to the need for association-based language. It reflects the study’s methodological transparency.
Evidence from Studies
Supporting (1)
The Resistance Training Dose Response: Meta-Regressions Exploring the Effects of Weekly Volume and Frequency on Muscle Hypertrophy and Strength Gains
The study says higher training volume and frequency are likely linked to bigger muscles and stronger muscles, but it doesn’t say they definitely cause it—just that the data strongly suggest a connection.