TY - JOUR AB -

This study investigated the effect of the inertial component of the resistance (INERTIA) at different intensity levels (LOAD) on force (FORCE), velocity (VELOCITY), power (POWER), and the muscle activity of the pectoralis major (PM), anterior deltoid (DA) and triceps brachii (TB) muscles during a chest press exercise. A motor-driven exercise apparatus was programmed to offer resistance with different inertial profiles over the range of movement (ROM): gravitational-type constant inertia (FULL); no-inertia (ZERO); linearly descending inertia along the ROM (VAR). Nine healthy adults performed five, maximal-effort, explosive movements with each inertial profile at 30, 50 and 70% of their 1 repetition maximum. Meanwhile, the PM, TB and DA signals were obtained jointly with the FORCE, VELOCITY and POWER readings returned by the exercise apparatus. One-dimensional statistical non-parametric maps based on 2-way repeated measures ANOVA (SnPM) were employed to evaluate the effect of LOAD and INERTIA on the collected time-series. Paired t-tests were then used as post-hoc tests on the portions of the ROM denoting significant differences in the SnPM. Higher LOAD resulted in elevated outcomes over large portions of the ROM in all the investigated time-series. Compared to FULL, ZERO allowed greater VELOCITY at the cost of lower FORCE throughout the ROM, while VAR, despite the lower VELOCITY han ZERO, resulted in higher FORCE and POWER output. In addition, ZERO and VAR elevated TB at the end of the ROM with respect to FULL. VAR overcame both FULL and ZERO in terms of FORCE and POWER, which indicates that variable inertial profiles might be effectively integrated into resistance exercise programs. Ultimately, this study suggested that INERTIA acts independently to the imposed LOAD on the FORCE, VELOCITY and POWER production. Coaches and therapists are encouraged to account for the type of INERTIA as one of the parameters considered during the exercise selection for their athletes or patients.

TI - The effect of variable inertial resistance on force, velocity, power and muscle activation during a chest press exercise. JO - bioRxiv DO - 10.1101/2023.12.16.572002 DA - 2023-12-17 UR - https://www.deepdyve.com/lp/biorxiv/the-effect-of-variable-inertial-resistance-on-force-velocity-power-and-2gA6Ak10wL SP - 2023.12.16.572002 DP - DeepDyve ER -