This data set provides that parameters needed to develop a computer model of the human lower limb. It is based on a model developed at the VA Rehabilitation R&D Center in Palo Alto California from 1987-1990. All data may be used and copied for non-commercial use. The data set includes descriptions of bone surfaces, joint kinematics, muscle lines of action, and muscle force-generating parameters. This data allows one to calculate the lengths, moment arms, forces, and joint moments generated by forty three muscles of the lower limb. The data set is presented in several files. The "Muscle_input_file" includes: (1) a dimensionless force-length curve for tendon, (2) dimensionless force-length curves for muscle, (3) a dimensionless force-velocity curve for muscle, (4) definitions of forty-three lower limb muscles. The definition of each muscle contains a list of coordinates that describe its line of action and the parameters (peak isometric force, optimal fiber length, tendon slack length, and pennation angle) needed to compute isometric muscle force. A more readable summary of musculotendon parameters is given in a separate table. The "Joint_kinematic_file" includes kinematic descriptions of the hip, knee, ankle, subtalar, and metatarsophalangeal joints. The "bones directory" includes approximate surface geometry for the bones of the lower limb. The format of these files is described in a file called "bone file format." You can download surface geometry for the pelvis, femur, patella, tibia, fibula, talus, foot, and toes. The patella, tibia, fibula, and bones of the foot were provided by Don Stredney of the Ohio State University.