Heart rate and metabolic cost of walking on the level were measured in 6 normal and 6 axillary crutch-users at four different walking speeds, namely. 0-56, 0-84, 112 and l-40m s It was observed that the axillary crutch-users expended a higher energy than the normal subjects during the walking at lower speeds than at higher speeds. Of the 4 speeds tested the minimum energy expenditure of each group occurred at the same one, namely, 112m although at this speed, the mean energy expenditure of the former group was 30 percent greater than the latter. The peak heart rate at the above mentioned speeds in both the groups showed the same response as the metabolic cost. It is thus suggested that peak heart rate might be used as a substitute for both an absolute and a comparative guide to metabolic cost in orthopaedic clinics and hospitals for measuring performance of lower extremity handicapped persons, provided all other factors which may affect it, remained unchanged. © 1980 Taylor & Francis Group, LLC.