A soft-inflatable exosuit for knee rehabilitation is fabricated in two different beam-like structures (I and O cross-section actuators) and mechanically characterized for their torque performance in knee-extension assistance. The fabrication procedure of both types of actuators is presented as well as their integration into a light-weight, low-cost and body-conforming interface. To detect the activation duration of the device during the gait cycle, a soft-silicone insole with embedded force-sensitive resistors (FSRs) is used. In evaluation studies, the soft inflatable exosuit device is tested for its ability to reduce muscle activity during the swing phase of the knee. Using sEMG (surface electromyography) sensors, the rectus femoris muscle group of a healthy individual is recorded while walking on a treadmill at a constant speed, with and without the soft device.