Effect of resistance training maintaining the joint angle-torque profile using a haptic-based machine on shoulder internal and external rotation

[Purpose] The aim of this study was to present an individualized resistance training method to enable exercise while maintaining an exercise load that is set according to an individual's joint angle-torque using a hapticbased resistance training machine. [Methods] Five participants (machine group. performed individualized shoulder internal and external rotation training with a haptic resistance training machine, while another five participants performed general dumbbell-based shoulder internal and external rotation training for eight weeks. Internal and external rotation powers of subjects were measured using an isokinetic machine before and after training. [Results] The average powers of both shoulder internal and external rotation has been improved after training (25.72%, 13.62%. The improvement in power of external rotation in the machine group was significantly higher than that in the control group. [Conclusion] This study proposes a haptic-based individualized rotator cuff muscle training method. The training protocol maintaining the joint angle-torque profile showed better improvement of shoulder internal/external rotation than dumbbell training.