Effect of Velocity-Based Loading on Acceleration Kinetics and Kinematics During Sled Towing

Sled towing (ST) provides an external load in the form of a sled towed using shoulder or waist harness and cord behind athlete. Loading strategies have varied greatly between studies, and despite many investigations, there is little agreement on the optimum loading to develop acceleration phase. The aim this study was investigate kinetics and kinematics velocity-based ST during acceleration phase sprinting. Twelve academy rugby league players performed series 6-m sprints different conditions; uninhibited, 10, 15, 20% velocity decrement (VDec). Sagittal plane kinematics kinetic measures were examined using 1-way repeated-measures analysis variance. Results indicated that affected trunk, knee, ankle AU5 joint (p < 0.05). Peak knee flexion increased as sled loads 0.05), which may enable athletes to lower their center mass increase horizontal force application. Net horizontal propulsive impulse measures greater all conditions 0.05), which significantly because loadings were heavier. In conclusion, highlights effects of differential help coaches understand acute kinetics and kinematic changes improve planning sprint training.