After 10 weeks of leg curls, it doesn’t matter if your foot is pointed up or down—you’ll get the same muscle growth and strength gains either way.
Scientific Claim
Ten weeks of prone leg curl training with either dorsiflexed or plantarflexed ankle positions produces similar increases in biceps femoris long head muscle thickness and isometric knee flexion torque in trained adults, indicating ankle position does not influence hypertrophy or strength gains.
Original Statement
“Experiment 2 revealed a significant pre‐ to post‐intervention increase in biceps femoris long head (BFLH) muscle thickness (p = 0.026) and isometric torque (p = 0.03), but there were no significant effects of the ankle position (p = 0.596) or interaction between ankle position and timepoint for these variables (p = 0.420).”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
probability
Can suggest probability/likelihood
Assessment Explanation
The study is a within-person RCT with explicit randomization and statistical non-significance for position effects (p = 0.596). The abstract uses neutral language, so 'likely has no effect' is appropriate.
More Accurate Statement
“Ten weeks of prone leg curl training with either dorsiflexed or plantarflexed ankle positions likely produces similar increases in biceps femoris long head muscle thickness and isometric knee flexion torque in trained adults.”
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.
Systematic Review & Meta-AnalysisLevel 1aWhether ankle position consistently has no effect on hamstring hypertrophy and strength across diverse populations and training protocols.
Whether ankle position consistently has no effect on hamstring hypertrophy and strength across diverse populations and training protocols.
What This Would Prove
Whether ankle position consistently has no effect on hamstring hypertrophy and strength across diverse populations and training protocols.
Ideal Study Design
A meta-analysis of all RCTs comparing dorsiflexed vs. plantarflexed ankle positions during hamstring-dominant exercises (e.g., leg curls) over ≥8 weeks, including at least 15 studies with 500+ participants, measuring BFLH thickness via ultrasound and isometric torque via dynamometer as primary outcomes.
Limitation: Cannot determine mechanisms or effects in untrained or clinical populations beyond those included.
Randomized Controlled TrialLevel 1bIn EvidenceCausal effect of ankle position on hamstring hypertrophy and strength over time.
Causal effect of ankle position on hamstring hypertrophy and strength over time.
What This Would Prove
Causal effect of ankle position on hamstring hypertrophy and strength over time.
Ideal Study Design
A double-blind, within-subject RCT with 40+ trained adults (20–45 yrs), randomized to perform 3x/week prone leg curls for 12 weeks with one leg dorsiflexed and the other plantarflexed, measuring BFLH muscle thickness via ultrasound and isometric knee flexion torque pre- and post-intervention.
Limitation: Cannot assess effects beyond trained individuals or longer timeframes.
Prospective CohortLevel 2bLong-term association between habitual ankle position and hamstring adaptations in real-world training.
Long-term association between habitual ankle position and hamstring adaptations in real-world training.
What This Would Prove
Long-term association between habitual ankle position and hamstring adaptations in real-world training.
Ideal Study Design
A 1-year prospective cohort tracking 200 resistance-trained individuals who consistently use either dorsiflexed or plantarflexed ankle positions during leg curls, measuring BFLH thickness and isometric torque every 12 weeks.
Limitation: Cannot control for confounding variables like training volume, nutrition, or recovery.
Evidence from Studies
Supporting (1)
The study had people do leg curls with their feet pointed up or down for 10 weeks and found that both ways made their hamstrings just as strong and big — so it doesn’t matter which foot position you use.