EFFECTS OF LOAD CARRIAGE ON CURVATURE OF THE SPINE

  • H. Orloff
  • P. Csonka
  • E. Csonka
  • T. Lee
Keywords: load carriage, backpack, spine curvature, fatigue

Abstract

The purpose of this study was to measure the curvature of the spine during load carriage in a rested and mildly fatigued condition. Twelve female subjects walked around an indoor track wearing a 9 kg backpack, in which fifteen spring loaded rods protruded from the back of the pack. The rods were separated by 1.9 cm and were designed to measure the curvature of the spine. The subjects walked for 21 minutes at a rate of 1.79 m/s. Fifteen samples were recorded over 2.5 s at 3 minutes and again at 18 minutes. The means of the two curves were derived from the data to achieve the mean rested and fatigued curves. With fatigue, the cervical to thoracic cavity was thrust forward, causing a significant increase in lordosis of the thoracic to lumbar region. With load carriage, increased lordosis was present to counter balance the weight of the backpack.