title: Effects of hand grip exercise on shoulder joint internal rotation and external rotation peak torque.
abstract: OBJECTIVE
  The goal of this study is to analyze the effects of hand grip training on shoulder joint internal rotation (IR)/external rotation (ER) peak torque for healthy people.
  
  
  METHODS
  The research was conducted on 23 healthy adults in their 20 s-30 s who volunteered to participate in the experiment. Hand grip power test was performed on both hands of the research subjects before/after the test to study changes in hand grip power. Isokinetic machine was used to measure the concentric IRPT (internal rotation peak torque) and concentric ERPT (external rotation peak torque) at the velocity of 60°/sec, 90°/sec, and 180°/sec before/after the test. Hand grip training was performed daily on the subject's right hand only for four weeks according to exercise program. Finally, hand grip power of both hands and the maximum torque values of shoulder joint IR/ER were measured before/after the test and analyzed.
  
  
  RESULTS
  There was a statistically significant difference in the hand grip power of the right hand, which was subject to hand grip training, after the experiment. Also, statistically significant difference for shoulder ERPT was found at 60°/sec.
  
  
  CONCLUSIONS
  Hand grip training has a positive effect on shoulder joint IRPT/ERPT and therefore can help strengthen muscles around the shoulder without using weight on the shoulder. Consequently, hand grip training would help maintain strengthen the muscles around the shoulder in the early phase of rehabilitation process after shoulder surgery.
authors.forename: Dong-Rour
authors.initials: DR
authors.lastname: Lee
authors.forename: Laurentius
authors.initials: L
authors.lastname: Jong-Soon Kim
mesh_terms: D000328:Adult; D001835:Body Weight; D015444:Exercise / Q000502:physiology; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D064797:Physical Conditioning, Human / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D012399:Rotation; D012785:Shoulder Joint / Q000502:physiology*; D019415:Torque; D055815:Young Adult
keywords: Hand grip training; grip power; shoulder joint external rotation peak torque; shoulder joint internal rotation peak torque