CHANGES IN UPPER BODY AND ARM KINEMATICS WHILE CARRYING SYMMETRICAL AND ASSYMETRICAL BACKPACK LOADS

  • Christian Stanford
  • Peter Francis
  • Henry Chambers
Keywords: backpack, kinematics, gait, adolescent

Abstract

The effects of different backpack carrying techniques on posture were investigated in 10 adolescent females. Subjects walked with no load, while carrying 20% bodyweight (BW) in a backpack with both shoulder straps and with 20% BW in a pack secured by one shoulder strap. Positions of skin markers attached to the trunk, pelvis, and upper extremities were recorded by a motion capture system. Mean angular positions and range of motion (ROM) for the trunk, pelvis, and shoulder were calculated. Results indicated that carrying 20% BW on both shoulders caused a significant increase in forward trunk inclination, a decrease in pelvic rotation, and changes in shoulder elevation and swing, relative to unloaded gait. When the backpack was supported by a single shoulder, numerous additional changes in posture were observed.