Internal Shoulder Rotation- 90◦

Muscles Involved

•  Rotator cuff
  • Teres Major
  • Subscapularis
• Pectoralis Major
• Anterior Deltoid
• Latissimus Dorsi

Athlete Positioning

• Facing away rack, slightly offset of vertical support post to ensure testing arm is line up with post
• Staggered or square stance
• Testing Arm is perpendicular to torso, and lower arm at a 90◦ angle with upper arm

Coach Positioning 

• Beside or behind athlete to ensure proper position and maximal effort is produced

Set Up

• Secure gStrength device
  • Attach to vertical support beam on rack or another secured vertical surface
  • Attach handle to gStrength device
• Ensure proper starting position for each athlete
  • Adjust vertical position of gStrength device as need to ensure proper arm position

Prepare to Test

• Select device, select athlete (if athlete is not entered do it now), select test.
• Tare device to ensure proper reading

To Test 

• Athlete has arm in proper starting position, with no slack in chain
• Athlete will grip handle securely, internally rotate shoulder while maintaining proper positioning, producing maximal force through shoulder joint for 3-5 seconds
  • Watch athlete “leaning” forward and using body weight to increase force produced
  • Isolate at shoulder joint
• Relax athlete after 3-5 seconds of maximal effort