title: The effects of elbow joint angle change on the elbow flexor muscle activation in pulley with weight exercise.
abstract: [Purpose] This research investigated the effect of angular variation of flexion of the elbow joint on the muscle activation of elbow flexor muscles. [Subjects] The research subjects were 24 male college students with a dominant right hand who had no surgical or neurological disorders and gave their prior written consent to participation with full knowledge of the method and purpose of this study. [Methods] The subjects' shoulder joints stayed in the resting position, and the elbow joint was positioned at angles of 55°, 70°, and 90°. The angle between the pulley with weights and forearm stayed at 90°. Surface electromyography was used to measure muscle activities. Three measurements were made at each elbow angle, and every time the angle changed, two minutes rest was given. [Result] The muscle activities of the elbow flexors showed significant changes with change in the elbow joint angle, except for the biceps brachii activities between the angles of 55° and 70° of elbow flexion. The muscle activities of the biceps brachii and brachioradialis showed angle-related changes in the order of 55°, which showed the biggest value, followed by 70° and 90°. [Conclusion] In order to improve muscle strength of the elbow flexor using a pulley system, it seems more effective to have a 90° angle between the pulley with weights and the forearm when the muscle is stretched to a length 20% greater than its resting position.
authors.affiliation: Department of Physical Therapy, Graduate School of College of Medical and Life Science, Silla University.
authors.forename: Taewook
authors.initials: T
authors.lastname: Kang
authors.forename: Youngjoon
authors.initials: Y
authors.lastname: Seo
authors.forename: Jaehoon
authors.initials: J
authors.lastname: Park
authors.forename: Eunseok
authors.initials: E
authors.lastname: Dong
authors.forename: Byungdo
authors.initials: B
authors.lastname: Seo
authors.forename: Dongwook
authors.initials: D
authors.lastname: Han
keywords: Joint angle; Muscle activation; Pulley with weight exercise