Men who started with a longer tendon lever arm and could already activate their thigh muscles better tended to get stronger in eccentric movements after training — their starting point mattered.
Scientific Claim
In previously untrained men, changes in eccentric knee extension strength after 10 weeks of heavy resistance training are associated with pre-training patellar tendon moment arm distance and percent voluntary activation, suggesting baseline anatomy and neural drive influence adaptation potential.
Original Statement
“The change in % VA and pre-training moment arm distance had substantial support for use in eccentric torque prediction models (AICc < 2)”
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 correctly uses 'associated with' and reflects the AICc model support without implying causation. The study design cannot prove these factors cause greater gains, only that they correlate.
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Randomized Controlled TrialLevel 1bThat individuals with higher pre-training moment arm or %VA experience greater eccentric strength gains when exposed to identical training.
That individuals with higher pre-training moment arm or %VA experience greater eccentric strength gains when exposed to identical training.
What This Would Prove
That individuals with higher pre-training moment arm or %VA experience greater eccentric strength gains when exposed to identical training.
Ideal Study Design
A double-blind RCT of 150 untrained men aged 18–40 stratified by pre-training moment arm and %VA, randomized to identical 10-week heavy resistance training, with eccentric torque as primary outcome to test if baseline values predict differential response.
Limitation: Cannot determine if these factors are causal or merely proxies for other unmeasured traits.
Longitudinal Cohort StudyLevel 2bIn EvidenceThe reproducible association between pre-training moment arm/%VA and eccentric strength gains across diverse populations.
The reproducible association between pre-training moment arm/%VA and eccentric strength gains across diverse populations.
What This Would Prove
The reproducible association between pre-training moment arm/%VA and eccentric strength gains across diverse populations.
Ideal Study Design
A prospective cohort of 300+ untrained individuals (men and women) aged 18–50 undergoing standardized 10-week resistance training, with pre-training moment arm (via X-ray) and %VA (via interpolated twitch) measured and correlated with eccentric torque change.
Limitation: Cannot control for training adherence, nutrition, or psychological factors.
Cross-Sectional StudyLevel 3Whether individuals with longer moment arms or higher %VA have greater baseline eccentric strength.
Whether individuals with longer moment arms or higher %VA have greater baseline eccentric strength.
What This Would Prove
Whether individuals with longer moment arms or higher %VA have greater baseline eccentric strength.
Ideal Study Design
A cross-sectional analysis of 400+ healthy adults aged 20–60, measuring patellar tendon moment arm via X-ray and %VA via interpolated twitch, and correlating with maximal eccentric knee extension torque.
Limitation: Cannot determine if these traits cause higher strength or result from prior activity.
Evidence from Studies
Supporting (1)
The study found that guys who started with a longer tendon lever arm and better muscle activation before training ended up getting stronger in knee extensions after 10 weeks — exactly what the claim says.