Comparison between the Camry and the Jamar Dynamometers in measuring hand grip strength in people with Inclusion Body Myositis

All participants will undergo testing of grip strength using two measurement methods, Jamar (existing 'gold standard' device) and Camry. Camry dynamometer: A commonly used alternative to the Jamar is the Camry dynamometer. The Camry which is a spring type dynamometer has been validated against the Jamar for use in a number of other populations. On a single testing occasion, participants will be asked to sit upright in a supported chair with their hips and knees at 90 degrees. Their feet should be flat on the ground. The shoulder of the side being tested is to be adducted against the side of the body, their unsupported elbow extended at neutral (0 degrees) and their wrist in a neutral position. Participants will then be instructed to grip the device as strongly as they can for 3 seconds. An average score from 3 attempts is recorded. Participants will be randomised to order of testing (Jamar or Camry first). Participants will be asked to use their dominant hand first. All attempts are supervised to ensure adherence to protocol. After a first attempt, there is a 30 second rest period before the second test, and another 30 second rest before the third attempt. This protocol will then be repeated on their non-dominant hand. An average score from the three attempts will be recorded for each side. Following 15 minutes rest time, the participant will be asked to activate the other device and perform three attempts using their dominant hand (with 30 second rest period between attempts). This protocol will then be repeated on the non-dominant side. As before, an average score will be recorded.