Dynamic postural stability for double-leg drop landing.
Dynamic postural stability has been widely studied for single-leg landing, but seldom considered for double-leg landing. This study aimed to evaluate the dynamic postural stability and the influence mechanism of muscle activities during double-leg drop landing. Eight recreationally active males and eight recreationally active females participated in this study and dropped individually from three heights (0.32 m, 0.52 m, and 0.72 m). Ground reaction force was recorded to calculate the time to stabilisation. Electromyographic activities were recorded for selected lower-extremity muscles. A multivariate analysis of variance was carried out and no significant influence was found in time to stabilisation between genders or limb laterals (P > 0.05). With increasing drop height, time to stabilisation decreased significantly in two horizontal directions and the lower-extremity muscle activities were enhanced. Vertical time to stabilisation was not significantly influenced by drop height. Dynamic postural stability improved by neuromuscular change more than that required due to the increase of drop height. Double-leg landing on level ground is a stable movement, and the body would often be injured before dynamic postural stability is impaired. It is understandable to protect tissues from mechanical injuries by the sacrifice of certain dynamic postural stability in the design of protective devices or athlete training.
Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China.
Wenxin
W
Niu
Ming
M
Zhang
Yubo
Y
Fan
Qinping
Q
Zhao
D000328:Adult; D001265:Athletic Injuries / Q000517:prevention & control*; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007866:Leg / Q000502:physiology; D035002:Lower Extremity / Q000502:physiology*; D008297:Male; D009068:Movement / Q000502:physiology*; D015999:Multivariate Analysis; D018482:Muscle, Skeletal / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D013314:Stress, Mechanical; D055815:Young Adult