When older women try to push with both legs at once on a leg press or pull with both arms on a lat machine, they’re weaker than when using each side separately—but this doesn’t happen when they extend their knees.
Scientific Claim
The bilateral deficit is present during leg press and lat pull-down exercises but absent during knee extension in post-menopausal women, indicating that the phenomenon is exercise-specific and not universal.
Original Statement
“A BLD was found for leg press and lat pull-down, but not for knee extension.”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
The study directly measured and compared BLD across exercises using controlled testing, allowing definitive statements about its presence or absence per movement.
Evidence from Studies
Supporting (1)
The effect of unilateral and bilateral strength training on the bilateral deficit and lean tissue mass in post-menopausal women
The study found that when women push or pull with both sides at once, they’re weaker than expected in some exercises (like leg press and lat pull-down) but not in others (like knee extension), meaning the weakness doesn’t happen in every movement.