Which of the following techniques can be used for assessing body composition?

Underwater weighing, also known as hydrostatic weighing, is a technique used to assess body composition by determining body density. In this method, an individual is submerged in water, and the weight is measured both in and out of the water. By using the principles of Archimedes’ buoyancy, the volume of water displaced by the body provides information about body density. This data can then be applied to equations that estimate body fat percentage and lean body mass.

This technique is widely regarded as one of the more accurate measures of body composition compared to other methods. It accounts for the water content of the body and differentiates between fat mass, which is less dense, and lean mass, which is denser.

The other options listed do not serve as methods for assessing body composition. Shoulder extension is a measure of flexibility and strength in the shoulder joint, the Thomas test assesses hip flexor tightness, and sprinting is a fitness activity that evaluates cardiovascular fitness and muscular strength but does not provide direct information about body fat percentage or other body composition metrics.