A small study addressed the question of whether one gets better results from performing resistance training reps at a self-selected pace or at a fixed rep duration (2-second concentric phase, 2-second eccentric phase). Researchers from universities in S├úo Paolo recruited 12 resistance-trained men and evaluated exercise volume, muscle activation and time under tension. Each participant did two high-intensity resistance exercise protocols: three sets of exercises at a self-selected pace and three sets of resistance training exercises at a fixed duration. Muscle activation was assessed with electromyography.
Data analysis showed that both exercise volume and muscle activation were higher when rep pace was self-selected. Time under tension was greater with the fixed-duration protocol.
The study is available in the Journal of Strength & Conditioning Research (2018; doi:10.1519/JSC.0000000000002493).