CHANGES OF TRUNK POSITION AND BREATHING PATTERN IN CHILDREN WALKING UNDER CONDITIONS OF LOAD CARRIAGE

Abstract

Twenty-five boys aged 10.31 ± 0.26 years were selected from a primary school. Each subject participated in four walking trials on a treadmill: one without a bag (0% of body weight) and three carrying school bags, weighing 10%, 15%, and 20% of the child’s body weight. Subjects walked at 1.1 m s-1 for 20 minutes on a treadmill. Walk movement was 2-D video filmed and analyzed. Tidal volume, respiratory frequency, and ventilation were measured with a cardiopulmonary function system before, during, and up until 3 minutes after the walk. The results show that there is a positive linear relationship between load weight, trunk forward lean, and breathing frequency. A 20-minute walk with a 20% load induced significant trunk forward lean and decreased trunk movement range, as well as increased respiratory frequency.