THE PREDICTION OF METABOLIC ENERGY-EXPENDITURE DURING GAIT FROM MECHANICAL ENERGY OF THE LIMB - A PRELIMINARY-STUDY

Measurements of metabolic energy-consumption and free-walking velocity were recorded for four persons with trans-femoral amputation with var iations of prosthesis mass and mass distribution. Hot-film anemometers , rate gyroscopes, and a force platform were used to measure prostheti c limb segment velocities and ground reaction forces. Metabolic energy consumption for the nine configurations of mass and mass distribution averaged 1.177 cal/kg/m with a standard deviation of +/-0.052 cal/kg/ m. Two measures of mechanical work of the amputated extremity, one bas ed on power developed across joints (W-1) and the other based on chang es in energy of the body segments (W-2), were computed to be 0.162+/-0 .014 and 0.175+/-0.025 cal/kg/m, respectively. A linear regression mod el led to rejections of both W-1 and W-2 as predictors of metabolic en ergy expenditure of the amputee at a significance level of 0.05.