Limb-Specific Associations Between Isokinetic Knee and Hip Variables and Contact Time Across Sprint Phases in Elite Sprinters

This study examined exploratory associations between isokinetic knee and hip variables and video-derived contact time across sprint acceleration. Nineteen male sprinters completed 60 m sprints; photocell timing gates recorded sprint times, and eight high-speed cameras operating at 240 frames/s provided contact and flight times. Bilateral concentric knee and hip flexion–extension were assessed at 60°/s and 240°/s for peak torque, relative peak torque, peak power, relative peak power, time to peak torque, and joint angle at peak torque. No statistically significant inter-limb differences were detected in the four torque/power outcomes or mean contact time. Two exploratory knee-extension comparisons at 240°/s yielded nominal raw p values below 0.05 for joint angle and time to peak torque, but neither remained statistically significant after Benjamini–Hochberg correction across 16 temporal/angular comparisons. After correction within four complete correlation families, 4 of 26 sprint-time–contact-time correlations remained statistically significant, all involving non-dominant-limb contact time. None of the 832 torque–contact-time, 832 power–contact-time, or 832 time-to-peak-torque/joint-angle-at-peak-torque–contact-time correlations remained significant. The isokinetic correlation patterns are therefore exploratory and require confirmation in larger samples using contact-time methods with established reliability and adequate temporal precision.