Load Carriage Model Development and Testing with Field Data

Abstract

The results of a field study of the energy cost of downhill walking and load carriage were used to test a modification of the Pandolf equation (PE) for the prediction of downhill load carriage energy costs. PE is a predictive equation for the energy cost of walking and load carriage on level and uphill terrain. The field study objective was to broaden the database to include slower walking speeds. A new dataset was collected in the field with loads of 0 kg and 27.2 kg at speeds of 0.89 m(x)/s and 1.12 m(x)s- on grades of 0%, -4%, -8.6% and -10.2%. Oxygen uptake was collected using portable oxygen monitors. To adjust the PE for downhill movement, a correction factor (CF) was derived using data from a prior laboratory study. The final equation is CF = hx(Gx(W+L)xV)/3.5 - ((W+L)x(G+6)2)/W) + (25-v2). The adjusted values, using the M = PE - CF format, fit well for walking at 1.12 m(dot)/s, but at 0.89 m(dot)/s, values were underestimated. Thus, an adjusted PE derived from a laboratory study for walking, and load carriage was valid at 1.12 m(dot)/s for loads up to 27 kg, but was not acceptable at 0.89 m(dot)/s.