The Effects of Backpack Load, Load Position, and Shock Absorb on Marching Physiological Cost and Subjective Assessment.

• Main Authors: Cheng chih-wen, 鄭智文
• Other Authors: 石裕川博士
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/30044130910582910601

碩士 === 國防大學管理學院 === 運籌管理學系 === 98 === Nowadays, the technique of national defense is growing very fast, and a soldier needs to carry more equipment on the battlefield. How to accomplish the mission quickly is the most important for an efficient troop. A well-designed backpack with will help soldiers to reach the goal. Backpack is the equipment that is more necessary in our daily life, and we can have more choices on back-pack for different purposes. That is why people care more about the features of the backpacks and pay more attention on ergonomic design. March is still a course in the training mission. During the march training, a soldier must be capable of carrying stuff for 20 kg, but it is a heavy loading for most people. There are some reasons which could affect the result of the march; such as marching speed, carrying methods, load, and the characteristics of backpack. This study intended to the effects of spring-device, load, and loading position on the physiological and subjective evaluation. This study recruited eight male volunteers from the National Defense Uni-versity to participate this experiment. The mean value in age, height, and weight were 28.4 years old, 175.2 cm, and 76.2 kg, respectively. The experimental de-sign of Split-Plot method was employed. The independent variables were the carrying load (10.5 and 21 kg, considered as a whole plot), equipped with the spring device or not, and the carrying position (low and high). The treatment combinations of spring and position were served as a subplot. The dependent variables include heart rate (HR), EMG (RMS and median frequency, MF) of trapezius and gastrocnemius, pressure on the right shoulder, out-side-displacement of the backpack, and the rating of perceived exertion (RPE). A total of eight treatment combinations were conducted by each subject, who was asked to walk on treadmill for 15 minutes with a constant speed of 5 km/hour, and then take a 15-minute rest. The results indicated that HR is lower when load is light, at a high position, or equipped with the spring-device. The MF of trapezius at low position is larger than at high position; the MF of gastrocnemius is smaller while backpack is at high position and without spring-device. As to the displacement, without spring-device at low position, the displacement is less than with spring-device at high position. As to the pressure on shoulder, it is smaller when the load is 10.5kg at the lower position; while loading the 21kg, with the spring-device and at high position has less pressure. On RPE for both shoulder and leg, the back-pack without spring-device is perceived less exerting; on the other hand, at high position with spring-device could make subjects feel less exerting on shoulder.