Sustainable transportation has been a focus area for over a decade, and the recent pandemic-induced lockdowns have witnessed a substantial increase in the demand for fitness equipment. Several studies have proposed different techniques for harvesting energy from human motion, such as piezoelectric footwear, backpacks, and wearable lightweight systems. This research aims to develop a low-cost and efficient technique for harvesting energy from a custom-built electric bike that can be used as a stationary exercise bike. Integrating electric bicycles as exercise bikes has become a viable solution to promote physical fitness and environmental responsibility. This technical paper explores the mechanical and electrical design of e-bikes as exercise bikes and the technical considerations required to create a functional and efficient hybrid machine. The technical aspects of integrating an electric bicycle with an exercise bike include modifying the frame to allow for a stationary position using high-quality materials to ensure durability, stability and long-term use. Secondly, designing a reliable drive system that allows for adjusting the resistance system, selecting appropriate batteries and control systems to manage energy consumption and recovery, including regenerative braking systems to store energy for later use. Lastly, incorporating a digital display for tracking performance metrics. The paper evaluates the benefits of using an electric bicycle as an exercise bike, including reducing carbon emissions, energy consumption, and economical strain on the user. The paper also evaluates the quantum of energy recovery possible from exercising, which depends on various factors such as the duration and intensity of the exercise and the efficiency of the energy recovery system. The paper analyzes the potential market for such a hybrid machine, including gyms, fitness centers, and personal use. Finally, a detailed cost study is performed to assess the return on investment. The findings presented in this paper suggest that e-bikes have the potential to offer a convenient and effective option for individuals seeking to improve their physical fitness and overall health.