Power Correction Model for Inclusive Handcycling on the Zwift Platform

Virtual cycling platforms such as Zwift have become widely used for indoor training and competition but remain primarily optimized for traditional leg-powered bicycles. As a result, handcyclists face a significant disadvantage, since upper-body power output is inherently lower than that generated by the legs—leading to an unbalanced, often discouraging experience. This study presents the development and validation of a power correction model designed to bridge this performance gap and promote inclusivity in virtual cycling environments. A custom-designed handbike was created to produce a digital twin and was physically modified for improved comfort and stability. The setup included a crankset-driven handcycle connected to a CompuTrainer, with an Arduino Due-based interface programmed to acquire and adjust power signals in real time before transmitting them to Zwift. Twenty-eight university students participated in the study. After an initial laboratory phase, the system was moved to a university gym, allowing for broader volunteer recruitment. Participants completed an Functional Threshold Power ramp test and a structured block protocol on both the handbike and a standard bicycle. Data collected included power output, cadence, heart rate, and perceived exertion (via the Borg scale). Results consistently showed that, for equivalent physiological effort, handbike power output was lower than that of the standard bicycle. This enabled the determination of individual correction factors, which were implemented directly in the Arduino system to adjust the power signal in real time. The results confirmed the technical feasibility of the correction model and its potential to enhance perceived fairness during virtual training. Several participants reported increased motivation and satisfaction when the correction model was active. This research represents a step toward more inclusive virtual training platforms, offering equitable participation for athletes using handcycles.