Effects of resistance training with controlled versus self-selected repetition duration on muscle mass and strength in untrained men

PeerJ. 2020 Mar 6:8:e8697. doi: 10.7717/peerj.8697. eCollection 2020.


The aim of this study was to compare the effect of self-selected repetition duration (SELF), with and without volume load (VL) equalized with controlled repetition duration (CON) on muscle strength and hypertrophy in untrained males. We used a within-subjects design in which 20 volunteers (age: 24.7 ± 2.9 years) had one leg randomly assigned to CON (i.e., 2 s concentric, 2 s eccentric) and the other to SELF or to self-selected repetition duration with equalized volume load (SELF-EV). One repetition maximum (1-RM) and muscle cross-sectional area (CSA) were measured at baseline (Pre) and after (Post) resistance training (RT; 2×/wk for 8 weeks). For the main study variables (1-RM and muscle CSA), a mixed-model analysis was performed, assuming repetition duration (SELF, SELF-EV and CON), and time (Pre and Post) as fixed factors and the subjects as random factor for each dependent variable (1-RM and CSA). All RT protocols showed significant increases in values of 1-RM from Pre (CON: 73.7 ± 17.6 kg; SELF: 75.9 ± 17.7 kg; and SELF-EV: 72.6 ± 16.9 kg) to Post (CON: 83.4 ± 19.9 kg, effect size (ES): 0.47; SELF: 84 ± 19.1 kg, ES: 0.43; and SELF-EV: 83.2 ± 19.9 kg, ES: 0.57, P < 0.0001). Muscle CSA values increased for all protocols from Pre (CON: 12.09 ± 3.14 cm2; SELF: 11.91 ± 3.71 cm2; and SELF-EV: 11.93 ± 2.32 cm2) to Post (CON: 13.03 ± 3.25 cm2, ES: 0.29; SELF: 13.2 ± 4.16 cm2, ES: 0.32; and SELF-EV: 13.2 ± 2.35 cm2, ES: 0.53, P < 0.0001). No significant differences between protocols were found for both 1-RM and CSA (P > 0.05). Performing RT with SELF, regardless of VL, was equally effective in inducing increases in muscle strength and hypertrophy compared to CON in untrained men.

Keywords: Cadence; Muscle hypertrophy; Muscle strength; Repetition velocity; Strength training.

Grants and funding

Talisson Santos Chaves was supported by grants from Coordination for the Improvement of Higher Education Personnel (CAPES) and Cleiton Augusto Libardi was supported by National Council for Scientific and Technological Development (CNPq, 302801/2018-9). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.