Muscle swelling from a workout can still be seen 3 days later, so measuring size then might not show real growth.
Scientific Claim
Muscle swelling induced by resistance training may persist for up to 72 hours post-exercise, potentially confounding hypertrophy measurements if assessed within this window.
Original Statement
“Muscle size was measured 72 hours after the final training session, and skeptics were unconvinced this was long enough for swelling to have fully subsided.”
Context Details
Domain
exercise
Population
human
Subject
muscle swelling from resistance training
Action
may persist
Target
up to 72 hours post-exercise, potentially confounding hypertrophy measurements
Intervention Details
Evidence from Studies
Supporting (3)
Comparison of the recovery response from high-intensity and high-volume resistance exercise in trained men
After intense weight training, muscles can stay swollen and sore for up to three days, which might make it look like they’re growing when they’re just puffed up — this study shows those effects last that long.
After a tough leg workout, the study found that muscles stayed swollen for at least 3 days, which could make it look like muscles are growing bigger when they’re just puffed up with fluid.
After lifting weights, your muscles swell up like a balloon, and this swelling doesn’t go away right away — it can last for days. This study shows that even 24 hours later, your muscles are still puffy, which could make it look like they’re growing bigger when they’re just swollen.
Technical explanation
This paper directly measures muscle thickness (MT) via ultrasound in elbow flexors after resistance training and shows that muscle swelling persists for at least 24 hours post-exercise, with cold-water immersion reducing this swelling — implying that swelling is present and measurable within the 72-hour window. This directly supports the assertion that muscle swelling may persist long enough to confound hypertrophy measurements.