Age-related differences in peak joint torques during the support phase of single-step recovery from a forward fall.
BACKGROUND
Previous studies have reported that older adults have a reduced ability to recover balance with a single step after a forward-induced fall. To better understand the reasons for this reduced ability, this study investigated any age-related differences in peak joint torques during the support phase of a single-step balance recovery from a forward fall.


METHODS
Ten young (19-23 years old) and 10 older (65-83 years old) men were released from forward-leaning positions and attempted to recover their balance with a single step. Lean was increased until they failed to recover their balance with a single step. Peak extensor torques were calculated for the support phase of balance recovery and were compared across age groups.


RESULTS
A consistent pattern of joint torques emerged during the support phase of balance recovery, suggesting a similar strategy across young and older participants. Despite this similarity, older participants exhibited smaller peak knee extensor torques during the support phase of single-step balance recoveries, and trends toward larger peak extensor torques at the hip and ankle.


CONCLUSIONS
The age-related differences found are believed to be the combined result of an age-related reduction in muscle strength and an age-related neuromuscular adaptation to mitigate the effects of muscle strength loss on physical performance capabilities.
Madigan
Michael L
ML
Department of Engineering Science and Mechanics (0219), Blacksburg, VA, 24061, USA. mlm@vt.edu
Lloyd
Emily M
EM
D000058:Accidental Falls; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D000843:Ankle Joint / Q000502:physiology; D006621:Hip Joint / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D019415:Torque; D016138:Walking / Q000502:physiology*