title: Characteristics of postural muscle activation patterns induced by unexpected surface perturbations in elite ski jumpers.
abstract: [Purpose] This study investigated the characteristics of postural control following postural disturbance in elite athletes. [Subjects] Ten elite ski jumpers and ten control subjects participated in this study. [Methods] Subjects were required to maintain balance without stepping following unexpected horizontal surface perturbation in a forward or backward direction. [Results] A lower and reproducible peak magnitude of the center of mass velocity was shown in the athlete group compared to the control group. Cross-correlation analyses showed longer time lags at the moment of peak correlation coefficient between trunk flexor and extensor muscle activities, and shorter time lags and higher correlations between ankle flexor and extensor muscle activities were shown in the athlete group than in the control group. [Conclusion] The elite ski jumpers showed superior balance performance following surface perturbations, more reciprocal patterns in agonist-antagonist pairs of proximal postural muscles, and more co-contraction patterns in distal postural muscles during automatic postural responses than control individuals. This strategy may be useful in sports requiring effective balance recovery in environments with a dynamically changing surface, as well as in rehabilitation.
authors.affiliation: Graduate School of Health Sciences, Hokkaido University, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Mani
authors.affiliation: Graduate School of Health Sciences, Hokkaido University, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Izumi
authors.affiliation: Graduate School of Health Sciences, Hokkaido University, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Konishi
authors.affiliation: Faculty of Health Sciences, Hokkaido University, Japan.
authors.forename: Mina
authors.initials: M
authors.lastname: Samukawa
authors.affiliation: Department of Sport Education, Hokusho University, Japan.
authors.forename: Keizo
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Center for Collaborative Research and Community Cooperation, Hiroshima University, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: Faculty of Health Sciences, Hokkaido University, Japan.
authors.forename: Tadayoshi
authors.initials: T
authors.lastname: Asaka
keywords: Muscle activation pattern; Postural reactions; Ski jumpers