Rehabilitation systems based on inertial measurement units (IMU) and bio-feedbacks are increasingly used in many different settings for patients with neurological disorders such as Parkinson disease or balance impairment, and more recently for functional recover after orthopedic surgical interventions or injuries especially concerning the lower limb. These systems claim to provide a more controlled and correct execution of the motion exercises to be performed within the rehabilitation programs, hopefully resulting in a better outcomes with respect to the traditional direct support of a physical therapists. In particular recruitment of specific muscles during the exercise is expression of its correct and finalized execution. The objective of this study was to compare muscular activation patterns of relevant lower limb muscles during different exercises performed with traditional rehabilitation and with a new validated system based on IMU and biofeedback (Riablo, Corehab, Trento, Italy). Twelve healthy subjects (mean age 28.1 ± 3.9, BMI 21.8± 2.1) were evaluated in a rehabilitation center. Muscular activation pattern of gluteus maximum, gluteus medium, rectus femoris and biceps femoris was recorded through surface EMG (Cometa; Milan) during six different motion tasks: hip abduction in standing position, lunge, hip flexion with extended knee in standing position, lateral lunge, hip abduction with extended knee in lateral decubitus, squat. Subjects performed 10 repetitions of each task for a total of 100 repetitions per motion task, with and without Riablo System as well as during standard rehabilitation. An additional IMU was positioned on the shank in order to detect beginning and end of each repetition. A single threshold algorithm was used to identify muscle activation timing. During hip abduction in standing position, gluteus maximum and rectus femoris showed a better and longer activation pattern while using Riablo compared to traditional rehabilitation. Gluteus medium showed a similar activation pattern whereas biceps femoris showed no activation from 30% to 80% using Riablo. During squat, rectus femoris and biceps femoris had a similar activation pattern with and without Riablo whereas gluteus maximum and gluteus medium showed a better activation pattern while using Riablo. The recent development of innovative rehabilitation systems meets the need of manageable, reliable and efficient instruments able to reduce rehabilitation costs but with the same good clinical outcomes. Muscular activation patterns of relevant lower limb muscles during selected motion tasks reveal their correct execution. The use of this new rehabilitation system based on IMU and biofeedback seems to allow a more selective and effective muscular recruitment, likely due to the more correct and controlled execution of the exercise, particularly for the identification and interdiction of possible compensation mechanisms