The energetic benefits of tendon springs in running: is the reduction of muscle work important?
The energetic benefits of tendon springs in running: is the reduction of muscle work important?
复制标题
DOI：
10.1242/jeb.112813
复制
发表时间：
2014-12-01
影响因子：
2.8
通讯作者：
Askew, Graham N.
中科院分区：
文献类型：
--
作者：
Holt, Natalie C.;Roberts, Thomas J.;Askew, Graham N.
草食动物的远端肌腱单位通常由短肌纤维和长而柔顺的肌腱组成。据推测，这些肌腱在步幅过程中储存和返回机械能的能力，从而避免了活动肌肉对机械能的循环吸收和再生，在跑步过程中提供了一些代谢能量的节省。然而，这一假设尚未得到直接检验。我们使用肌肉测力计和肌热测量来确定肌肉产生力量的成本，如果机械能被肌腱储存和返回，肌肉就可以等长地发挥作用，如果机械能被肌肉吸收和再生，肌肉就可以进行主动拉伸缩短周期。我们发现，与拉伸-缩短循环相比，等长循环中的力产生成本没有可检测到的差异。这一结果表明，用肌腱弹性能量储存和恢复代替肌肉拉伸缩短功并不能降低力产生的成本。这就对肌肉功的减少驱动长远端肌腱进化的假设提出了质疑。我们认为肌腱的能量效益主要来自于它们对肌肉和肢体结构的影响，而不是它们减少肌肉循环工作的能力。
The distal muscle-tendon units of cursorial species are commonly composed of short muscle fibres and long, compliant tendons. It is assumed that the ability of these tendons to store and return mechanical energy over the course of a stride, thus avoiding the cyclic absorption and regeneration of mechanical energy by active muscle, offers some metabolic energy savings during running. However, this assumption has not been tested directly. We used muscle ergometry and myothermic measurements to determine the cost of force production in muscles acting isometrically, as they could if mechanical energy was stored and returned by tendon, and undergoing active stretch-shorten cycles, as they would if mechanical energy was absorbed and regenerated by muscle. We found no detectable difference in the cost of force production in isometric cycles compared with stretch-shorten cycles. This result suggests that replacing muscle stretch-shorten work with tendon elastic energy storage and recovery does not reduce the cost of force production. This calls into question the assumption that reduction of muscle work drove the evolution of long distal tendons. We propose that the energetic benefits of tendons are derived primarily from their effect on muscle and limb architecture rather than their ability to reduce the cyclic work of muscle.