International Sports Sciences Association (ISSA) Trainer Practice Exam

The correct choice is based on the specific function and application of each method listed. Hydrostatic weighing, DEXA (Dual-Energy X-ray Absorptiometry), and bioelectrical impedance analysis (BIA) are all recognized techniques used to assess body composition. Hydrostatic weighing determines body density by comparing the weight of a person in water to their weight on land, allowing for the calculation of body fat percentage. DEXA uses low-level X-rays to differentiate between bone mass, lean body mass, and fat mass, making it a highly accurate body composition measurement tool. BIA estimates body composition by sending a low-level electrical current through the body and measuring resistance, which varies according to the body's fat and water content. In contrast, electromyography (EMG) is a technique used to evaluate and record the electrical activity of skeletal muscles. It measures how muscles respond to nervous stimulation rather than assessing body composition. This fundamental difference in purpose categorizes electromyography as unrelated to body composition assessments, thereby making it the correct choice for the question.