Supervision during resistance training positively influences muscular adaptations in resistance-trained individuals

ABSTRACT

This study compared the effects of supervised versus unsupervised resistance training (RT) on measures of muscle strength and hypertrophy in resistance-trained individuals. Thirty-six young men and women were randomly assigned to one of two experimental, parallel groups to complete an 8-week RT programme: One group received direct supervision for their RT sessions (SUP); the other group performed the same RT programme in an unsupervised manner (UNSUP). Programme variables were kept constant between groups. We obtained pre- and post-study assessments of body composition via multi-frequency bioelectrical impedance analysis (MF-BIA), muscle thickness of the upper and lower limbs via ultrasound, 1 repetition maximum (RM) in the back squat and bench press, isometric knee extension strength, and countermovement jump (CMJ) height. Results showed the SUP group generally achieved larger increases in muscle thickness for the triceps brachii, all sites of the rectus femoris, and the proximal region of the vastus lateralis. MF-BIA indicated increases in lean mass favoured SUP. Squat 1RM was greater for SUP; bench press 1RM and isometric knee extension were similar between conditions. CMJ increases modestly favoured UNSUP. In conclusion, our findings suggest that supervised RT promotes greater muscular adaptations and enhances exercise adherence in young, resistance-trained individuals.

KEYWORDS:

• intensity of effort, adherence, resistance exercise
• hypertrophy
• strength

Acknowledgments

We would like to acknowledge the following research assistants for assisting with data collection: Max Sapuppo, Max Weisenthal, Konstantinos Tolos, Kae Kuratomo, Yi Jing Cheng, Kurt Roderick, Alisha Alston.

Disclosure statement

BJS serves on the scientific advisory board for Tonal Corporation, a manufacturer of fitness equipment. All other authors report no conflicts of interest in regard to this manuscript.

Author contributions

Conceptualisation: BJS, ADV; Formal analysis: ADV; Investigation: MC, RB, CB, AP, FA, JM; Methodology: BJS, ADV, MC, JPF; Writing, interpretation, review and editing: MC, RB, CB, AP, FA, JM, JPF, DO, ADV, BJS. All authors have read and agreed to the published version of the manuscript.

Data availability statement

The data are available at: https://osf.io/96zxw

Supplementary material

Supplemental data for this article can be accessed online https://doi.org/10.1080/02640414.2023.2261090

Additional information

Funding

This study was supported by a PSC-CUNY grant (#65333-00 53) and a FPU pre-doctoral grant (FPU18/00686).