Your muscles don’t get bigger or smaller right after a single workout, no matter how hard or how many reps you do.

Scientific Claim

High-volume resistance exercise (8 sets of 10 repetitions) does not significantly alter vastus lateralis cross-sectional area (CSA) acutely in trained men, indicating that muscle size changes are not detectable within 72 hours post-exercise.

Original Statement

“Muscle morphological [cross-sectional area (CSA) of vastus lateralis] assessments were performed at baseline (BL), 30-min (P-30 min), 24-h (P-24 h), 48-h (P-48 h), and 72-h (P-72 h) post-exercise... no significant changes in CSA were reported.”

From study:Comparison of the recovery response from high-intensity and high-volume resistance exercise in trained men

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 claim accurately reflects the absence of reported CSA changes, and the study design supports causal inference for acute effects.

Evidence from Studies

Supporting (0)

No supporting evidence found

Contradicting (1)

Comparison of the recovery response from high-intensity and high-volume resistance exercise in trained men

Randomized Controlled Trial

Human

2017 Jul

The study checked if muscles got bigger right after a tough workout and found no noticeable change within 3 days—so yes, you can’t see muscle growth that soon.

Source Study

Comparison of the recovery response from high-intensity and high-volume resistance exercise in trained men

Score: 46

DOI: 10.1007/s00421-017-3598-9

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