As the indoor cycling trainer industry keeps innovating, a cycling trainer that has a similar longitudinal motion to outdoor cycling does not yet exist. Therefore, this thesis aimed to design a simulator controller that can actively simulate longitudinal cycling motion and assess its performance in translating outdoor longitudinal cycling dynamics to the indoor cycling trainer setup. Since the thesis concerned an indoor cycling setup the amount of allowed longitudinal motion was ± 20 cm. We performed a literature review and motion study on the topic of longitudinal bicycling dynamics, whereafter equations of motion of outdoor cycling were defined to address the difference between inand outdoor cycling. The gathered knowledge was then used to design a simulator controller for an indoor cycling setup that is actuated in the longitudinal direction through a linear actuator. To evaluate the performance of the simulator controller torque data of 4 different test subjects was collected and used as the input signal for the controller to theoretically assess its simulation performance. The simulator controller simulations, of 7 different slope angles for both seated and standing cycling, resulted in minimal longitudinal motion of the simulated trainer setup during low-resistance cycling situations and maximal motion during high-resistance cycling situations. During the simulations, the simulated cycling trainer setup stayed well within the maximal allowable ± 20 cm from its initial position. The intra-pedal stroke range of motion of the simulations was similar to the intra-pedal stroke range of motion measured on a cycling treadmill through a motion capture study. This thesis concludes that it is possible to translate outdoor longitudinal cycling dynamics to an indoor cycling simulator with torque as the only input. The theoretical assessment of the simulator controller shows that the metrics meet the requirements and are similar to real-world cycling.