The measurement of the mechanical properties is a crucial point for new engineered muscle tissues. The final aim is to implant these tissues to substitute or restore the functionality of impaired muscles, so that functional properties as close as possible to the healthy native muscles are required. We developed an engineered skeletal muscle tissue, X-MET, whose strong point is to be created without any endogenous component. This construct is able to contract spontaneously as well as to respond to electrical stimulation. In this work, we developed an experimental system to measure for the first time, the power developed by the X-MET. The power was measured by applying the isovelocity contraction technique. This technique has never been applied on muscle engineered tissues so far, so the aim of this work was to find out the optimal stimulation parameters. Once determined the range of displacement and velocity of shortening for which the X-MET was able to develop power, we proceeded looking at the optimal parameters allowing the production of its maximum power. Preliminary tests showed that the X-MET generates the optimal power when stimulated to shorten 3% of its ideal length at a speed of 0.2 L0/s.