This is the study of how living organisms move, grow, etc. in relation to mechanical principles.
Alternately, the study of the body in terms of its mechanical structure and properties. Locomotion of the body is one of the more important things to which the mechanical laws are applied for study.
From the BioTech Dictionary at http://biotech.icmb.utexas.edu/. For further information see the BioTech homenode.