Clinical Sciences/Health Conditions
Satoshi Shibata, PhD
Assistant Professor
Ibaraki Prefectural University of Health Sciences
Ami-machi, Ibaraki, Japan
Kakeru Umemoto, BS
Physical Therapist
Tsukuba Medical Center Hospital
Tsukuba-City, Ibaraki, Japan
Return-to-play (RTP) test batteries after ACL injury mainly assess strength, hop performance, and psychological readiness. However, these tasks are predictable and may not adequately reflect the complex demands of team sports. This pilot study aimed to examine the biomechanical effects of a cognitive dual-task during single-leg landing.
Design:
Fourteen male handball players (171.6 ± 5.1 cm, 63.6 ± 6.1 kg, 21.2 ± 1.7 years) performed single-leg landings under three conditions: baseline, congruent Stroop, and incongruent Stroop tasks. Participants jumped forward 50% of body height over a 10-cm obstacle and landed on the non-dominant leg on a force plate while verbally responding to the Stroop task. Kinematics and kinetics were collected using an eight-camera system (250 Hz) and force plate (1000 Hz). Joint angles and moments were analyzed from initial contact (IC) to 100 ms post-IC. Flight time (FT) and jump height (JH) were also compared across conditions using one-way ANOVA.
Results:
In the incongruent Stroop condition, knee flexion angle and vertical ground reaction force were significantly greater than baseline (p < 0.05). FT and JH also increased compared with baseline (p < 0.05). No significant differences were observed in knee valgus angle or joint moments.
Conclusion:
A visual Stroop dual-task altered landing biomechanics by increasing knee flexion and GRF, suggesting potential influence on ACL injury risk. The observed increases in FT and JH may represent compensatory strategies to maintain performance without elevating knee valgus loading. As this pilot protocol constrained jump distance for safety, future studies should incorporate maximal-effort hops with dual-task demands to better simulate RTP testing.
