Taking less rest between sets of weightlifting makes your body work harder, raises your heart rate, makes your muscles burn more lactic acid, and feels much more exhausting.
Scientific Claim
Reducing inter-set rest periods from 120 seconds to 60 seconds during a hypertrophic resistance training session increases maximal blood lactate concentration by approximately 0.9–1.1 standardized effect sizes, elevates heart rate during work and rest phases by moderate to large effect sizes (ES = 0.6–1.4), and raises perceived exertion by large effect sizes (ES = 1.2–1.8) in active men, indicating a greater metabolic and perceptual stress response.
Original Statement
“Shorter inter-set rest periods displayed moderate increases in maxLac, HR and RPE responses in all conditions.”
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 is a randomized controlled trial with direct physiological measurements and effect sizes exceeding moderate thresholds, justifying definitive causal language for acute outcomes.
Evidence from Studies
Supporting (1)
The study found that taking only 60 seconds of rest between sets (instead of 120 seconds) made participants’ hearts beat faster, built up more lactic acid in their blood, and felt harder to them — exactly what the claim says.