Kinetics and energetics during uphill and downhill carrying of different weights

During physically heavy work tasks the musculoskeletal tissues are exposed to both mechanical and metabolic loading. The aim of the present study was to test a biomechanical model for prediction of whole-body energy turnover from kinematic and anthropometric data during load carrying. Total loads of 0, 10 and 20 kg were carried symmetrically or asymmetrically in the hands, while walking on a treadmill (4.5 km h(-1)) horizontally, uphill, or downh ill the slopes being 8%. Mean values for the directly measured oxygen uptak e ranged for all trials from 0.5 to 2.11 O-2 min(-1), and analysis of varia nce showed significant differences regarding slope, load carried, and symme try. The calculated values of oxygen uptake based on the biomechanical mode l correlated significantly with the directly measured values, fitting to th e line Y = 0.990 X + 0.144, where Y is the estimated and X is the measured oxygen uptake in 1 min(-1). The close relationship between energy turnover rate measured directly and estimated based on a biomechanical model justifi es the assessment of the metabolic load from kinematic data. (C) 2000 Elsev ier Science Ltd. All rights reserved.