Muscular force in running turkeys: The economy of minimizing work

Science

Volumn 275, Issue 5303, 1997, Pages 1113-1115

  Roberts, Thomas J ^a,b   Marsh, Richard L ^b   Weyand, Peter G ^a   Taylor, C Richard ^a  

^a HARVARD UNIVERSITY   (United States)

^b NORTHEASTERN UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ANIMAL EXPERIMENT; ANIMAL TISSUE; ARTICLE; BODY MOVEMENT; BODY WEIGHT; CELL ENERGY; CONTROLLED STUDY; GASTROCNEMIUS MUSCLE; LIMB MOVEMENT; MUSCLE FIBER CONTRACTION; MUSCLE FORCE; MUSCLE FUNCTION; NONHUMAN; PRIORITY JOURNAL; RUNNING; TENDON; TURKEY (BIRD);

ANIMALS; BIOMECHANICS; ELECTROMYOGRAPHY; HINDLIMB; ISOMETRIC CONTRACTION; LOCOMOTION; MUSCLE CONTRACTION; MUSCLE, SKELETAL; RUNNING; STRESS, MECHANICAL; TENDONS; TRANSDUCERS; TURKEYS;

ANIMALIA; AVES; MELEAGRIS GALLOPAVO;

EID: 0031016676     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.275.5303.1113     Document Type: Article

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19. Data for the work during shortening are presented because this work is relevant to the energy cost of contraction. The net work done by muscle fibers is equal to the work done by the muscle (during shortening) minus the work done on the muscle (during lengthening). During level running, the muscle also underwent a small amount of active lengthening so that the net work performed by the muscle was not significantly different from zero at all running speeds. Although this result is consistent with the fact that steady-speed running on level ground requires little net work, it is not inevitable; some muscles could perform net positive work while other muscles act as net work absorbers.
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29. The authors thank C. I. Buchanan for technical assistance and A. A. Biewener and R. Kram for comments on the manuscript. Supported by grants from NIH to C.R.T. (AR18140) and R.L.M. (AR39318) and by an NSF graduate fellowship to T.J.R. This paper is dedicated to the memory of C. Richard Taylor.