Premium
Walk the Walk: Parallels between Gait Parameters and Muscle Force Production in Turkeys
Author(s) -
Vega Karina,
Eng Carolyn,
Roberts Thomas J.
Publication year - 2018
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.2018.32.1_supplement.862.10
Subject(s) - stride , treadmill , kinematics , gait , physical medicine and rehabilitation , ground reaction force , mathematics , contact force , anatomy , physics , medicine , physical therapy , classical mechanics , quantum mechanics
Running and walking involve regular patterns of limb kinematics, which can be characterized by simple parameters such as stride frequency and foot contact time. It is not clear whether these regular patterns of timing are mirrored at the level of muscle function, or whether variable sharing of force among different muscles might result in timing within individual muscles that does not reflect the timing of limb movements. We used direct measurements of force production in the lateral gastrocnemius (LG) muscle of wild turkeys during walking and running to test the hypothesis that stride parameters measured from limb movements would match those measured from muscle force production at all speeds of walking and running. Muscle force was measured via strain gauges attached to the bony tendon of the muscle, and stride parameters were measured with high‐speed video as animals ran on a treadmill at a range of walking and running speeds (1 to 3.5 m/s). Stride frequency and stride time values measured from video matched those determined from the onset of muscle force for all speeds. Time of foot contact measured from video decreased continuously with speed. Time of force development for the LG also decreased with speed, but the time spent in force development in the LG was significantly lower than the time the foot was on the ground for all speeds. The fraction of time the muscle was generating force was relatively constant across speed, with the muscle producing force for approximately 50% of the period of foot ground contact. This observation indicates that there is a temporal sharing of the task of force production between different muscles during the step, and that this sharing may remain relatively fixed across walking and running speeds. Such temporal sharing of force development should be considered in models of locomotor mechanics and energetics, and may be relevant to rehabilitative strategies for gait disorders. Support or Funding Information The Integrative Organismal Systems Physiology (IOSP) Undergraduate Summer Research Fellowship that made this research possible was supported by the American Physiological Society and a grant from the National Science Foundation (NSF) Integrative Organismal Systems (Award No. IOS‐1238831). Support from NIH grant AR‐055295 is also gratefully acknowledged. This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .