Trunk muscle activity and kinematics during boxing and battle rope exercise in people with motor-complete spinal cord injury

Context Recovery of seated balance is a rehabilitation priority for people with motor-complete spinal cord injury (mcSCI). Previous research has demonstrated that people with mcSCI can voluntarily engage their trunk muscles during different exercise programs that have the potential to improve seated balance control. Boxing and battle rope exercises could offer another opportunity to improve seated balance for people with mcSCI, but it is unknown if this type of exercise engages trunk musculature and challenges seated balance. Objective To describe the movement patterns of people with mcSCI compared to controls by characterizing the muscle activation patterns and kinematics of the trunk and upper-body during boxing and battle rope exercise. Design Cross-sectional study. Participants 4 males with mcSCI between C7-T9, and 4 able-bodied controls. Methods Participants performed different boxing and battle rope exercises while kinematics and electromyography (EMG) from the trunk and arms were recorded. Outcome Measures Trunk EMG amplitude, trunk and arm joint angles, and trunk curvature. Results Boxing and battle ropes elicited higher relative EMG activity in people with mcSCI compared to controls (P < 0.001). Participants with mcSCI had similar upper-limb kinematics during the exercises to controls, but demonstrated reduced trunk rotation and increased trunk curvature. Conclusions These findings suggest that boxing and battle rope can elicit trunk activity in people with mcSCI, though they may adopt increased trunk curvatures. Future research should explore if such exercise programs may improve seated balance in people with mcSCI.