When doing leg presses, taking only 1 minute of rest between sets makes you breathe harder overall than taking 3 minutes, but this doesn’t happen when doing chest flys—your body handles short breaks better when using smaller muscles.
Scientific Claim
Shortening rest intervals between sets from 3 to 1 minute increases accumulated oxygen uptake during horizontal leg press exercises in healthy, resistance-trained men, but has no significant effect during chest fly exercises, indicating that fatigue accumulation is more sensitive to rest interval manipulation in large-muscle-group movements.
Original Statement
“The 1-minute RI induced higher accumulated VO2 during LP (p < 0.05) but not during CF.”
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 RCT design with repeated measures and statistical significance (p < 0.05) supports causal language. The claim is limited to the studied population and exercises, avoiding overgeneralization.
Evidence from Studies
Supporting (1)
The effect of Between-Set Rest Intervals on the Oxygen Uptake During and After Resistance Exercise Sessions Performed with Large- and Small-Muscle Mass
When people do leg presses with less rest between sets, their bodies work harder and use more oxygen—but the same doesn’t happen with chest flys. This means shorter breaks help big muscle exercises get more tired (and burn more oxygen), but not small ones.