When people with IBD attend outpatients clinic with their IBD specialist they are weighed and their BMI calculated to indicate if they are poorly nourished. Weight and BMI may not always provide a good assessment of how well nourished a person is because it does not describe the amount of muscle in the body in proportion to fat. A person with a low or decreasing amount of muscle but a normal or high BMI is at risk of nutritional problems. Measuring the amount of muscle someone with IBD has in routine practice poses a challenge to clinicians due to time constraints. One-way of measuring the amount of muscle a person has is to measure their muscle strength. This can be measured by recording the strength of a person's handgrip. Handgrip strength can be measured using a hand-held device called a dynamometer.