After a heavy leg workout, men can't push as hard with their legs for at least two days — even though they're trained, their strength is still a little weaker.
Scientific Claim
Maximal isometric leg extension force is reduced by approximately 40% immediately after heavy resistance exercise and remains 8% below baseline at 48 hours post-exercise in strength-trained men, indicating persistent neuromuscular fatigue.
Original Statement
“Maximal isometric force decreased during the entire course of the exercise session down to 60 ± 12% (from 3,505 ± 568 N to 2,087 ± 389 N, p < 0.05) of pre-exercise level... Maximal isometric force was still 8 ± 10% lowered (p < 0.05) on the second day of recovery after the exercise as compared to the prelevel.”
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 reports precise numerical changes and time points from direct measurements, avoiding causal language. The design supports descriptive and quantitative claims about within-subject changes.
Evidence from Studies
Supporting (1)
After a tough leg workout, the men’s leg strength stayed weaker for two days, which matches the claim that heavy lifting causes long-lasting muscle fatigue.