Abstract
INTRODUCTION: This study investigated whether velocity-based resistance training provides additional benefits to lower limb performance compared to standard exercise execution. METHODS: Twenty untrained adult women (37-55 years) were randomly assigned to two resistance training groups to perform resistance training with three sets of four lower body exercises per week for 6 weeks. The number of repetitions and lifting velocity differed between the groups. One group performed lower body exercises with maximal intent and a 10% velocity loss threshold termination (VB10%; n = 10), while the other group performed 10 repetitions at a standard 1:2 s concentric:eccentric tempo (STD; n = 10). The number of repetitions was recorded during the sessions. Before and after the intervention, power, muscular endurance and dynamic stability of the lower limbs were assessed using the mean propulsive velocity (MPV) and power (MPP) at 70% one-repetition maximum in the squat and deadlift, the Y-balance test (YBT) and the 30-second sit-to-stand test (STS), respectively. A two-way analysis of variance was used to assess the effects of time, group, and their interaction. RESULTS: The difference between 10 repetitions in the STD and repetitions in the VB10% was assessed using a one-sample t-test. Both groups significantly improved MPP, MPV, YBT and STS [mean difference (MD) ≥5.4%; effect size (ES) ≥0.6]. Although 2.5-2.7 less repetitions were performed in VB10%, the improvements in MPP and MPV were slightly greater (ES ≥ 1.2 vs. ≥ 0.8). Conversely, STS and YBT improved more in STD (ES ≥ 0.4 vs. ≥ 1.0). DISCUSSION: Regardless of the lifting method used, the training intervention improved lower limb power, muscular endurance and dynamic stability, indicating that resistance training is an effective strategy for enhancing these capacities in untrained adult women. Using 10% threshold may be a more time-efficient strategy for improving lower-limb power in this population and could represent a promising approach for mitigating early declines in power over time.