Design of a Soft Wearable Passive Fitness Device for Upper Limb Resistance Exercise

An increase in health awareness has fueled the development of fitness equipment or devices nowadays. Most conventional fitness devices have had some issues in space limitation and the high cost of equipment. With the advance in wearable robotics, we proposed a soft passive fitness wearable device for upper limb resistance exercises such as chest press, frontal raise, and chest fly. Users can customize the exercise intensity by adjusting the length of the elastic bands embedded in the wearable device. Moreover, the exer-tainment (Exercise-entertainment) user display interface was designed to motivate the user. Movements of users were estimated using inertial measurement units (IMUs), and haptic feedback was provided through the vibro-stimulation. Furthermore, the effectiveness of the proposed device was evaluated with the Borg scales representing the rating of perceived exertion (RPE) and measuring the surface electromyography (sEMG) of the three muscles located one on the shoulder and two on the chest. Both the Borg 6-20 and CR 10 scales were increased, and the normalized sEMG activities of the upper limb muscles with the activated device had more than double in magnitude compared to that with a bare condition; therefore, the proposed device has a potential effectiveness as for resistance exercise. Overall, this research devotes preliminary evidence on the benefits of the device in promoting the user to work out and contributing to the exercise effects.