Does lifting slow or fast make your muscles bigger?

Original Title

Equalization of Training Protocols by Time Under Tension Determines the Magnitude of Changes in Strength and Muscular Hypertrophy

Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms

Summary

Two groups lifted weights with the same total time under tension but different speeds — one slow, one fast. Both got equally strong and their muscles grew the same overall size.

Sign up to see full results

Get access to research results, context, and detailed analysis.

Surprising Findings

The distal region of the triceps grew more than the middle and proximal regions, even though training was identical across groups.

Most assume muscle growth is uniform along a muscle’s length; this shows regional differences can occur even with controlled volume, challenging assumptions about how hypertrophy distributes.

Practical Takeaways

If you're short on time, you can do faster reps as long as you keep the total time under tension the same (e.g., 36s/set) and maintain the same number of sets and intensity.

low confidence

Unlock Full Study Analysis

Sign up free to access quality scores, evidence strength analysis, and detailed methodology breakdowns.