Fig. 1

Overview of the experimental set-up (top) and the cross-over practice protocol for synchronous (Syn) and asynchronous (Asyn) handcycling (bottom). Top: The participants, equipped with a mask and heart rate monitor for cardiopulmonary exercise testing (CPET), rode in the attach-unit experimental handcycle with kinematic markers on the motor driven treadmill at 1.94 m/s. During the practice sessions, a pulley system was attached to the back of the handcycle to impose resistance [32]. Bottom: The experimental protocol consisted of a pre-test, three practice sessions, and a post-test, all structured in three blocks of 4 min of exercise with 2 min rest in between. After completion the protocol was repeated for the other crank mode (Syn/Asyn). In between sessions was a two-day break (~). The fourth and very last minute of exercise in each crank mode were analyzed to compare the effects of crank mode and motor learning