Mixed

Limiting repetition velocity loss to 20% during resistance training yields greater improvements in explosive power (countermovement jump) and preserves fast-twitch muscle fiber types (MHC-IIX) compared to allowing 40% velocity loss, despite producing significantly lower total training volume and less muscle hypertrophy.

If your goal is explosive power (like jumping or sprinting), stop your sets when your bar speed drops by 20% from your fastest rep. Do not push until you are slow or failing. This approach builds power and preserves fast-twitch muscle fibers better than training close to failure, even though you do fewer total reps. If your goal is pure muscle size, you might need to train closer to failure (40% velocity loss).