This paper proposes a new model for electric energy production, using physical workout that is done daily in spinning bicycles and elliptical trainers in gyms. Two gyms were visited and the kinetic energy generated for the machines was evaluated in order to determine the most efficient machine and the amount of energy the machine can produce. Having the machine design, the next step is to simulate with the defined parameters, getting as a result the generated energy vs. consumed energy curve. Finally, a feasibility analysis is made using the free software Retscreen International V.4.0. This way, a model is proposed for energy generation using a group of those machines, in order to reach a possible implementation on Colombian gyms.