Dynamics of leg muscle function in tammar wallabies (M. eugenii)during level versus incline hopping

摘要: The goal of our study was to examine whether the in vivo force-length behavior, work and elastic energy savings distal muscle-tendon units legs tammar wallabies (Macropus eugenii) change during level versus incline hopping. To address this question, we obtained measurements muscle activation (via electromyography), fascicle strain sonomicrometry) force tendon buckles) from lateral gastrocnemius (LG) plantaris (PL) muscles trained hop on a an inclined (10°, 17.4% grade) treadmill at two speeds (3.3 m s^(-1) 4.2 s^(-1)). Similar patterns activation, were observed under both conditions. This also corresponded similar limb timing movement (duty factor, contact time hopping frequency). During hopping, LG PL exhibited stretch shortening that yielded low levels net [LG: level, -1.0±4.6% (mean ± s.e.m.) vs incline, 0.6±4.5%; PL: 0.1±1.0% 0.4±1.6%] (LG: -8.4±8.4 J kg^(-1) -6.8±7.5 muscle; -2.0±0.6 -1.4±0.7 muscle). Consequently, neither significantly altered its contractile dynamics do more Whereas electromyographic (EMG) phase, duration intensity did not differ for LG, shorter but intense periods together with reduced EMG phase (P<0.01), Our results indicate design spring-like economical generation is key these wallaby, need accommodate changes associated locomotion achieved by proximal limb.