Electromyography activity across gait and incline: The impact of muscular activity on human morphology
Version of Record online: 7 JUL 2010
Copyright © 2010 Wiley-Liss, Inc.
American Journal of Physical Anthropology
Volume 143, Issue 4, pages 601–611, December 2010
How to Cite
Wall-Scheffler, C. M., Chumanov, E., Steudel-Numbers, K. and Heiderscheit, B. (2010), Electromyography activity across gait and incline: The impact of muscular activity on human morphology. Am. J. Phys. Anthropol., 143: 601–611. doi: 10.1002/ajpa.21356
- Issue online: 18 NOV 2010
- Version of Record online: 7 JUL 2010
- Manuscript Accepted: 15 MAY 2010
- Manuscript Received: 28 OCT 2009
- NIH. Grant Number: RR 25012
- NSF Graduate Fellowship
- human locomotion;
- gluteus maximus
The study of human evolution depends upon a fair assessment of the ability of hominin individuals to gain access to necessary resources. We expect that the morphology of extant and extinct populations represents a successful locomotory system that allowed individuals to move across the environment gaining access to food, water, and mates while still maintaining excess energy to allocate to reproduction. Our assessment of locomotor morphology must then incorporate tests of fitness within realistic environments—environments that themselves vary in terrain and whose negotiation requires a variety of gait and speeds. This study assesses muscular activity (measured as the integrated signal from surface electromyography) of seven thigh and hip muscle groups during walking and running across a wide range of speeds and inclines to systematically assess the role that morphology can play in minimizing muscular activity and thus energy expenditure. Our data suggest that humans are better adapted to walking than running at any slope, as evidenced by small confidence intervals and even trends across speed and incline. We find that while increasing task intensity unsurprisingly increases muscular activity in the lower limb, individuals with longer limbs show significantly reduced activity during both walking and running, especially in the hip adductors, gluteus maximus, and hamstring muscles. People with a broader pelvis show significantly reduced activity in the hip adductor and hamstring muscles while walking. Am J Phys Anthropol, 2010. © 2010 Wiley-Liss, Inc.