Hydraulic Resistance Device for Force, Power, and Force-Velocity-Power Profile Assessment During Resisted Sprints with Different Overloads

This study aimed to evaluate the ability of a hydraulic resistance device (HRD) to assess the force and power output and force-velocity-power profile of short sprints, while examining the effects of hydraulic overload on these outcomes. Twenty-eight amateur athletes performed 20 m sprints under minimal (MiL), moderate (MoL), and high (HiL) overloads. Sprint velocity was measured with the HRD, while resistance force (F-r) was assessed from the pressure via the HRD and from the reaction force via the force plate (FP). Using velocity and F-r during the sprints, maximal velocity (v(max)), average horizontal force (F-avg), average power (P-avg), and FvP profile variables (F-0, v(0), and P-max) were calculated. A two-way ANOVA analysed the effects of overload and calculation method. In addition, a correlation between the HRD and FP measurements was evaluated. For all variables, very high to excellent correlation between the HRD and FP was observed (r >= 0.96). However, the F-avg, P-avg, F-0, and P-max calculated by the HRD were lower than the FP across all overloads (eta(2) >= 0.51; p < 0.001). Regardless of the method used, F-avg, P-avg, and F-0 were highest at HiL (eta(2) >= 0.38; p < 0.001), and v(0) was highest at MiL (eta(2) = 0.35; p < 0.001), whereas overload had no significant effect on P-max (eta(2) = 0.01; p = 0.770). The HRD is a feasible means for monitoring force and power output during hydraulic resisted sprints but should not be directly compared to other resistance devices. HiL produced the highest F-avg, P-avg, and F-0 and may be optimal for increasing power output and improving acceleration performance.