Does Spreading Your Reps Over More Range Build More Muscle Than Partials at the Top?

Lifters love to argue about partials, and most of them are arguing about the wrong half of the rep. The interesting question isn't whether partials "count." It's whether training a muscle at long muscle lengths — the stretched position under load — beats training it at short, contracted lengths. And the research over the last few years has gotten loud about this.

A 2021 study from Pedrosa and colleagues had trainees do leg extensions either through the lengthened portion of the range or the shortened portion. The lengthened group grew more muscle at the distal portion of the quad, despite the same total work (see [1]). That lines up with a broader pattern: Maeo and colleagues found that training the triceps long head in a stretched, overhead position produced substantially more growth than the same exercise done with the arm at the side (see [2]). And Ottinger and colleagues, in a 2023 review of the training-at-long-muscle-length literature, concluded the stretch-biased position has a real, repeatable hypertrophy edge — not a small one (see [3]).