Biomechanical analysis of rowing with different movement constraints

While many studies have explored able-bodied rowing biomechanics, only a few focus on the effect of movement constraints. This study analyzes 3D kinematics and joint power during rowing under different movement constraints. Also differences between participants with and without physical impairments are explored. Four setups are used to simulate gradually increasing movement constraints: Setup 1 - standard rowing conditions (mirrors able-bodied rowing and the PR3 para-rowing class); Setup 2 - rowing with a fixed seat, with legs still on the foot-stretcher (mirrors the PR2 para-rowing class for athletes with some residual leg functions); Setup 3 - fixed seat with legs not on the foot-stretcher (PR2 para-rowing class athletes without leg functions); Setup 4 - movement constraints applied to legs and trunk (PR1 para-rowing class). Fourteen participants, including three with physical impairments, performed in ergometer-based sub-maximal rowing bouts in the four setups. Those without physical impairments were grouped, while those with impairments were assessed individually. 3D motion capture data was gathered at 100 Hz and forces from both the handle and the foot-stretcher of the ergometer were recorded respectively at 1500 Hz and 200 Hz. Additionally, oxygen uptake, blood lactate and perceived exertion were collected to ensure a sub-maximal intensity. General variables such as stroke rate and length, power output, and handle force were examined across the setups. Typically, the stroke length decreased with increased constraints, necessitating higher stroke rates. Increased constraints were also associated with decreased power output and a reduced handle force. Participants with impairments typically showed the same behavior as the able-bodied participants. However, participant A exhibited lower stroke rate values and employed a different rowing technique with a shorter drive phase. Transitioning from setup 1 to setup 2 increased the range of motion in the shoulder, trunk, and pelvis. Moreover, in setup 3 and 4, reduced trunk flexion/extension and shoulder range of motion. Although participants with physical impairments often mirrored the able-bodied behavior, they occasionally displayed different range of motion. Particularly, participant B showed higher shoulder adduction and rotation range of motion while participant C demonstrated reduced upper limb range of motion in all planes. Unsurprisingly, the study showed a reduction in power output in joints influenced by the constraints, such as in the trunk and leg’s joints which suggest reduced rowing performance. The relative contribution to overall power in the elbow and shoulder increased across the setups. However, with the exception of the increased shoulder power from setup 1 to setup 2, the power produced by the shoulder and elbow joints remained stable across setups, suggested no compensation occurred in response to the added constraints. This behavior in the elbow joint was also consistent among the participants with impairments, although, in the shoulder joint, from setup 3 to setup 4, they exhibited an increase in power demand. While this research enhances our understanding of how the biomechanics of rowing change under different movement constraints, further studies are recommended. These should encompass classified para-rowers to provide a more comprehensive overview of para-rowing biomechanics.