Force, velocity and power relationship of ankle plantar flexors and ankle dorsiflexors in the elderly

本研究旨在探讨老年人踝跖屈肌和踝背屈肌的力、速度和功率关系的特点。用特制的装置测量了15名老年男性（G-岁）和15名男大学生（G-青年）的跖屈肌和背屈肌输出的力、速度和合成功率，并根据Hill公式计算了力-速度关系：（F+a）（V+B）=（Fmax+a）B。下肢的前后横截面积（CSA-ante，CSA-poste）由超声仪测量的肌肉厚度的平方估计。两年龄组之间CSA后测值无显著性差异，但G-年龄组CSA前测值显著低于G-青年组。最大功率值在Pmax、Fmax和Vmax上存在显著性差异（G-aged < G-young）。与G-年轻相比，G-老年显示出Pmax（69.1%）比Fmax（69.5%）更大的降低 ...更多信息 跖屈肌的Pmax（69.4%）较背屈肌的Fmax（81.8%）和Vmax（78.9%）降低更明显。跖屈肌群的Fmax/CSA-poste、Pmax/CSA-poste和Vmax/下肢长的比值G-老年组显著低于G-青年组。而背屈肌群Famx/CSA-poste和Pmax/Csa-poste Vmax/下肢长的比值，老年组与青年组相比无显著性差异。力-速度曲线的G-老化倾向于低于G-年轻。背屈肌Vmax、V_1、V_2、V_3、<10>V_4<20>、<30>V_5<45>、V_6<60>在不同%Fmax负荷下，老年组与青年组间差异显著，而跖屈肌Vmax、V_4、V_6、V_6在不同%Fmax负荷下差异不显著。G年龄组和G年轻组的跖屈肌和背屈肌激动剂和拮抗剂的iEMG和%iEMG均无显著差异，这些结果表明，随着年龄的增长，肌肉力量发展能力可能比神经因素在功能上下降得更多。少

The present study aimed to investigate the characteristics of force, velocity and power relations of ankle plantar flexors and ankle dorsiflexors in elderly. The subjects were 15 elderly men (G-aged) and 15 college male students (G-young) Using specially designed apparatus, the force, velocity and resultant power output by the plantar-and dorsi-flexors muscles were measured, and the force-velocity relations were calculated according to Hill's equation: (F+a)(V+b)=(Fmax+a)b. Ante and post cross-sectional area (CSA-ante, CSA-poste) of the lower limb was estimated from the square of the muscle thickness measured by an ultrasonic apparatus. In CSA-poste, no significant difference was observed between the two age groups, however, the CSA-ante was significantly lower in G-aged than in G-young. The maximal power values were significant differences (G-aged < G-young) in Pmax as well as in Fmax and Vmax. Compared with G-young, G-aged showed a greater reduction in Pmax (69.1%) than Fmax (69.5%) … More and Vmax (82.8%) of the plantar-flexors, and also showed a greater reduction in Pmax (69.4%) than Fmax (81.8%) and Vmax (78.9%) of the dorsi-flexors. The ratios of Fmax/CSA-poste, Pmax/CSA-poste and Vmax/lower limb length of the plantar-flexors were significantly lower in G-aged than in G-young. However the ratios of Famx/CSA-poste and Pmax/Csa-poste Vmax/lower limb length of the dorsi-flexors were no significant in G-aged than in G-young. The force-velocity curves of G-aged tended to be lower than that of the G-young. There were significant differences among G-aged and G-young for Vmax, V_<10>, V_<20>, V_<30>, V_<45> and V_<60> in the dorsi-flexors, however, not for under various %Fmax load in the plantar-flexors. The iEMG and %iEMG of agonist and antagonist for the plantar-and dorsi-flexors were no significant between G-aged and G-young.From these results, it was suggested that the ability to develop muscular power may be reduced more functionally than neural factor with increasing age. Less