Different Cues Leading to Meaningful Differences in Contact Mat Countermovement Jump Assessment in Collegiate Team Sport Athletes: A Preliminary Study

Abstract

Contact mats estimate countermovement jump (CMJ) height via flight time, assuming consistent body positioning at take-off and landing. However, foot landing technique, specifically soft versus stiff landings, may alter ankle and joint angles, potentially biasing jump height measurements. This study investigated the effect of externally cued ankle-focused landing styles- specifically ball-of-foot (“soft”) versus heel-first (“stiff”) landings on CMJ height measured by a contact mat in collegiate male team sport athletes. One hundred male team sport athletes (age 21.4 years; height 182.3 cm; weight 78.6 kg) performed CMJs under randomized, counterbalanced soft (ball-of-foot, greater plantar flexion) and stiff (heel-first, minimal plantar flexion) landing conditions. Jump height was measured with the Just Jump contact mat using the Bosco protocol. Participants completed three trials per condition; average jump heights obtained under the soft and stiff landing conditions were compared using paired t-tests, while Pearson correlation and Bland-Altman analysis assessed the relationship and agreement between two landing styles. CMJ height was significantly greater during stiff landings (48.50 ± 5.51 cm) compared to soft landings (45.62 ± 5.80 cm), with a mean difference of 2.88 cm (p = 0.001, Cohen’s d = 1.28). A strong positive correlation (r = 0.92) indicated consistent ranking across conditions, but Bland-Altman analysis revealed systematic bias and moderate variability between landing styles. Landing technique substantially influences CMJ height measurements using a contact mat, with stiff landings producing inflated jump heights. However, this preliminary study did not include biomechanical verification of landing mechanics, which should be considered in future research.These findings highlight the need for standardized, explicit ankle landing instructions during CMJ testing to ensure accuracy and comparability of results in sport performance assessment and monitoring.