Muscle Function in Locomotion
Muscle is the motor that drives locomotion. Our recent studies in this area have focused on questions
such as: how do the different tasks that muscles perform during walking contribute to the total metabolic
cost, and how does muscle fiber type distribution influence the mechanics and energetics of movement.
Current research is focused on understanding the effects of musculoskeletal design on the energetic
cost of locomotion, and on developing improved models that link muscle structure and mechanics with
metabolic energy consumption. Current work is supported by grants from the UMass Research Office.
Evolution of Bipedalism
Walking upright on two straight legs is one of the key evolutionary adaptations that sets humans apart
from other primates. However, it is difficult to understand the evolutionary events that led to our current
condition based on the fossil record alone. In this research, we are using computer models of modern
humans, chimpanzees, and extinct human ancestors to better understand the energetic consequences
of specific evolutionary adaptations in the structure of the bones and muscles in the legs. This should
lead to a better understanding of the transition to habitual bipedalism in early human ancestors. This
work is being pursued in collaboration with colleagues from Stony Brook University (New York), and is
supported by a grant from the National Science Foundation.
Gait in Special Populations
People who experience difficulty walking, such as individuals who use lower-limb prostheses or children
with cerebral palsy, commonly have a cost of walking two-to-three times higher than able-bodied people.
This may be partly due to poor regulation of the mechanical energy generated by their muscles. We are
currently using 3-D musculoskeletal models to determine how mechanical energy is generated and
controlled to produce walking. These mechanical analyses are combined with measurements of
physiological cost, which together will shed new light on the causes of inefficient gait in clinical
conditions. This work is being pursued in collaboration with colleagues from the UMass Amherst
Mechanical and Industrial Engineering Department and the Shriners Hospital for Children. The research
on gait in lower limb amputees is supported by the National Center for Simulation in Rehabilitation
Research while the work on gait in children is supported by Kosair Charities.
Locomotion Research Group
Locomotion Research Group
Department of Kinesiology
University of Massachusetts
30 Eastman Lane
Amherst, MA 01003-9258