The assessment can estimate body-fat mass, lean body mass and bone mineral density. This provides more detailed information than body weight or body mass index alone.

DEXA uses specialised dual-energy X-ray equipment to assess the composition of the body.

Weight loss alone does not show whether the weight came from fat mass or lean tissue. During an overly restrictive diet, an individual may lose valuable lean mass as well as fat.

Conversely, someone completing strength and cardiovascular training may gain muscle while losing fat. Their total weight could remain stable or even increase despite a positive change in body composition.

For example, an increase of five kilograms of lean mass combined with a five-kilogram reduction in fat mass would produce no net change on the scales, even though the individual's composition had changed substantially.

Understanding how body fat is distributed can provide additional context when reviewing health, nutrition and body-composition goals.

Repeated scans can also help track whether a training or dietary intervention is changing overall and regional body composition over time.

Identifying lower bone mineral density can help inform conversations about appropriate training, nutrition and further medical assessment.

This may be especially relevant for athletes involved in non-weight-bearing sports such as cycling. Suitable weight-bearing exercise, strength training and appropriate nutrition can support bone health.

A body-composition assessment does not replace diagnosis or personalised medical advice from a qualified healthcare professional.

It may be particularly useful for people aiming to reduce body fat, build or preserve lean mass, establish a baseline, monitor changes across a training block or better understand their general health profile.

Repeat assessments are most valuable when testing conditions are kept reasonably consistent, allowing changes to be compared more meaningfully.