Kinematic analysis of the European Enhanced Exploration Exercise Device in unpowered mode

Unlike earlier short-duration lunar missions, current exploration-class missions include extended periods of microgravity exposure prior to lunar surface operations. Current exercise systems on the International Space Station are bulky and power-intensive, limiting their applicability for deep space missions. The European Enhanced Exploration Exercise Device (E4D) addresses these constraints by combining aerobic and resistive exercises in a compact, multifunctional device. This study compared kinematics and perceived exertion between exercises performed on E4D's unpowered mode and conventional gym equipment. Fourteen participants performed rowing, seated row, deadlifts, and bench press under both conditions while wearing a sensor-based motion capture system. Differences in joint angles, angular velocities, and perceived exertion were observed, likely influenced by variations in ergonomics, force production mechanics, and load distribution. Whilst differences were significant, full-body aerobic and resistive exercises were possible using a single device without a motor to generate resistance, relevant for missions with volume and power constraints.