Tam Nicholas, Tucker Ross, Santos-Concejero Jordan, Prins Danielle, Lamberts Robert P
Int J Sports Physiol Perform. 2019 Jan 1;14(1):16-22. doi: 10.1123/ijspp.2018-0151.
It is debated whether running biomechanics make good predictors of running economy, with little known about the neuromuscular and joint-stiffness contributions to economical running gait.
To understand the relationship between certain neuromuscular and spatiotemporal biomechanical factors associated with running economy.
Thirty trained runners performed a 6-min constant-speed running set at 3.3 m·s-1, where oxygen consumption was assessed. Overground running trials were also performed at 3.3 m·s-1 to assess kinematics, kinetics, and muscle activity. Spatiotemporal gait variables, joint stiffness, preactivation, and stance-phase muscle activity (gluteus medius, rectus femoris, biceps femoris, peroneus longus, tibialis anterior, and gastrocnemius lateralis and medius) were variables of specific interest and thus determined. In addition, preactivation and ground contact of agonist-antagonist coactivation were calculated.
More economical runners presented with short ground-contact times (r = .639, P < .001) and greater stride frequencies (r = -.630, P < .001). Lower ankle and greater knee stiffness were associated with lower oxygen consumption (r = .527, P = .007 and r = .384, P = .043, respectively). Only lateral gastrocnemius-tibialis anterior coactivation during stance was associated with lower oxygen cost of transport (r = .672, P < .0001).
Greater muscle preactivation and biarticular muscle activity during stance were associated with more economical runners. Consequently, trained runners who exhibit greater neuromuscular activation prior to and during ground contact, in turn optimizing spatiotemporal variables and joint stiffness, will be the most economical runners.
跑步生物力学是否能很好地预测跑步经济性仍存在争议，对于神经肌肉和关节僵硬度对经济跑步步态的贡献知之甚少。
了解与跑步经济性相关的特定神经肌肉和时空生物力学因素之间的关系。
30名训练有素的跑步者以3.3米/秒的速度进行6分钟的匀速跑步，在此期间评估耗氧量。还以3.3米/秒的速度进行地面跑步试验，以评估运动学、动力学和肌肉活动。时空步态变量、关节僵硬度、预激活和支撑相肌肉活动（臀中肌、股直肌、股二头肌、腓骨长肌、胫骨前肌以及腓肠肌外侧头和内侧头）是特别感兴趣的变量，因此对其进行了测定。此外，还计算了激动剂-拮抗剂共激活的预激活和地面接触情况。
经济性更好的跑步者地面接触时间较短（r = 0.639，P < 0.001），步频较高（r = -0.630，P < 0.001）。较低的踝关节僵硬度和较高的膝关节僵硬度与较低的耗氧量相关（分别为r = 0.527，P = 0.007和r = 0.384，P = 0.043）。仅支撑期外侧腓肠肌-胫骨前肌的共激活与较低的运输氧耗相关（r = 0.672，P < 0.0001）。
支撑期更大的肌肉预激活和双关节肌肉活动与经济性更好的跑步者相关。因此，在地面接触之前和期间表现出更大神经肌肉激活，进而优化时空变量和关节僵硬度的训练有素的跑步者，将是最经济高效的跑步者。
