%0 Generic %A Koushyar, Hoda %A Bieryla, Kathleen A. %A A. Nussbaum, Maury %A L. Madigan, Michael %D 2019 %T Age-related strength loss affects non-stepping balance recovery %U https://plos.figshare.com/articles/dataset/Age-related_strength_loss_affects_non-stepping_balance_recovery/7606037 %R 10.1371/journal.pone.0210049 %2 https://plos.figshare.com/ndownloader/files/14121083 %2 https://plos.figshare.com/ndownloader/files/14121086 %K non-stepping balance recovery Aging %K balance recovery capability %K Age-related strength loss %K platform displacement %K non-stepping balance recovery capability %K age-related strength loss %K balance recovery ability %K hip flexion strength %K plantar flexor strength %K age-related reductions %X

Aging is associated with a higher risk of falls, and an impaired ability to recover balance after a postural perturbation is an important contributing factor. In turn, this impaired recovery ability likely stems from age-related decrements in lower limb strength. The purpose of this study was to investigate the effects of age-related strength loss on non-stepping balance recovery capability after a perturbation while standing, without constraining movements to the ankle as in prior reports. Two experiments were conducted. In the first, five young adults (ages 20–30) and six community-dwelling older adults (ages 70–80) recovered their balance, without stepping, from a backward displacement of a support surface. Balance recovery capability was quantified as the maximal backward platform displacement that a subject could withstand without stepping. The maximal platform displacement was 27% smaller among the older group (11.8±2.1 cm) vs. the young group (16.2±2.6 cm). In the second experiment, forward dynamic simulations of a two-segment, rigid-body model were used to investigate the effects of manipulating strength in the hip extensors/flexors and ankle plantar flexors/dorsiflexors. In these, typical age-related reductions in strength were included. The model predicted lower maximal platform displacements with age-related reductions only in plantar flexion and hip flexion strength. These findings support the previously reported age-related loss of balance recovery ability, and an important role for plantar flexor strength in this ability.

%I PLOS ONE