Theoretical considerations for muscle-energy savings during distance running.

摘要: Abstract We have recently demonstrated that the triceps surae muscles energy cost (ECTS) represents a substantial portion of total metabolic running (Erun). Therefore, it seems relevant to evaluate factors which dictate ECTS, namely amount and velocity shortening, since is likely these will Erun. Erun morphological AT mechanical properties were obtained in 46 trained elite male female distance runners using ultrasonography dynamometry. ECTS (J·stride−1) at speed lactate threshold (sLT) was estimated from force crossbridge mechanics energetics. To estimate relative impact on mean values for speed, body mass, resting fascicle length (Lf), Achilles tendon stiffness moment arm maximum isometric plantarflexion torque obtained. calculated across range (mean ± 1 sd) each independent factor. Average sLT 233 m·min−1. At this 255 J·stride−1. Estimated shortening 0.08 Vmax level muscle activation 84.7% torque. Compared lowest factor, higher associated with 39% reduction 81% 31% activation. Longer arms elevated masses an increase 18% 23%, respectively. These results demonstrate low achieved primarily high exemplified runners.