Quantitative assessment of lower-limb biomechanics during a standardized jive kick: Within-session reliability, measurement error, and repetition strategy

This study characterized within-session measurement performance of lower-limb biomechanical outcomes during a standardized Jive kick across repetition numbers, assessed sensitivity to repetition selection, and examined changes across consecutive repetitions. Fifteen highly trained female Latin dancers performed six repetitions with synchronized three-dimensional kinematics and ground-reaction forces. Sagittal-plane hip, knee, and ankle range of motion (ROM) and maximum net joint power were evaluated using absolute-agreement intraclass correlation coefficients, 95% confidence intervals, SEM, SEM%, and MDC95. Single-repetition ICCs ranged from 0.544 to 0.900; hip and knee ROM showed lower relative measurement error, whereas maximum net joint power showed greater error. Averaging generally improved measurement stability, but small power subsets were sensitive to repetition selection. No outcome showed a significant linear trend across six consecutive repetitions after multiplicity adjustment; an isolated non-monotonic effect occurred for right-knee maximum net joint power. For knee ROM, six-repetition MDC95 was 8.9°–9.9° bilaterally versus 21.8°–24.2° for a single repetition. For hip and knee ROM, three repetitions may be considered to reduce testing burden. Five offer a pragmatic option for ankle ROM. Six provide the most conservative strategy for maximum net joint power. These are data-informed configurations rather than universal minima or optima.