کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10431947 | 910231 | 2014 | 5 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Decay of force transients following active stretch is slower in older than young men: Support for a structural mechanism contributing to residual force enhancement in old age
ترجمه فارسی عنوان
فرسودگی گذرهای نیروی پس از کشش فعال در مردان مسن تر از مردان جوانتر است: حمایت از یک مکانیزم ساختاری کمک به افزایش نیروی باقیمانده در سن
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کلمات کلیدی
سالخورده، عضله، غیر عادی، افزایش نیروی باقی مانده، سفتی، سختی،
موضوعات مرتبط
مهندسی و علوم پایه
سایر رشته های مهندسی
مهندسی پزشکی
چکیده انگلیسی
Following active lengthening of muscle, force reaches an isometric steady state above that which would be achieved for a purely isometric contraction at the same muscle length. This fundamental property of muscle, termed “residual force enhancement (RFE),” cannot be predicted by the force-length relationship, and is unexplained by the cross-bridge theory of muscle contraction. Recently, we showed that older adults experience higher RFE than young for the ankle dorsiflexors primarily owing to a greater reliance on passive force enhancement (PFE) and similar RFE for the knee extensors but a greater contribution of PFE to total RFE. Natural adult aging may prove a useful model in exploring mechanisms of RFE which may reside in the dissipation of force transients following stretch. A post-hoc analysis was conducted on previously described RFE experiments in young (~26 years) and old (~77 years) men for the dorsiflexors and knee extensors to fit the force following stretch with a biexponential decay. In both muscle groups the decay half-life of the first exponential was two times slower in the older compared with young men. There were significant associations between PFE and the decay in force, suggesting a greater “non-active” contribution to total RFE across muscles in older compared with young men. The greater “non-active” component of RFE in older adults could be due to structural age-related changes causing increased muscle stiffness during and following stretch.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Biomechanics - Volume 47, Issue 13, 17 October 2014, Pages 3423-3427
Journal: Journal of Biomechanics - Volume 47, Issue 13, 17 October 2014, Pages 3423-3427
نویسندگان
Geoffrey A. Power, Walter Herzog, Charles L. Rice,