Influence of age on neuromuscular control during a dynamic weight-bearing task.
Neuromuscular control strategies might change with age and predispose the elderly to knee-joint injury. The purposes of this study were to determine whether long latency responses (LLRs), muscle-activation patterns, and movement accuracy differ between the young and elderly during a novel single-limb-squat (SLS) task. Ten young and 10 elderly participants performed a series of resistive SLSs (approximately 0-30 degrees) while matching a computer-generated sinusoidal target. The SLS device provided a 16% body-weight resistance to knee movement. Both young and elderly showed significant overshoot error when the knee was perturbed (p < .05). Accuracy ofthe tracking taskwas similar between the young and elderly (p = .34), but the elderly required more muscle activity than the younger participants (p < .05). The elderly group had larger LLRs than the younger group (p < .05). These results support the hypothesis that neuromuscular control of the knee changes with age and might contribute to injury.
Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, IL, USA.
Sangeetha
S
Madhavan
Sarah
S
Burkart
Gail
G
Baggett
Katie
K
Nelson
Trina
T
Teckenburg
Mike
M
Zwanziger
Richard K
RK
Shields
D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D002490:Central Nervous System / Q000502:physiology; D004576:Electromyography; D005080:Exercise Test; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D007866:Leg / Q000502:physiology*; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D011795:Surveys and Questionnaires; D013647:Task Performance and Analysis; D013997:Time Factors; D014891:Weight Lifting / Q000502:physiology; D016474:Weight-Bearing / Q000502:physiology*; D055815:Young Adult