This work presents the evaluation of a new control system of Functional Electrical Stimulation (FES) for applying strategies for artificial activation of the ankle joint muscles. In particular, we present an investigation of the direct effects of event-driven open loop FES assistance of the ankle muscles during walking on the lower limb kinematics in able-bodied individuals (n = 5) and one incomplete spinal cord injured (iSCI) patient. We analyzed gait kinematics between walking with and without FES assistance. Effects consistent with normal physiological gait were obtained, but some unexpected alterations also occurred. Therefore, further studies are needed to help adjust the FES strategy.