Report

Dual-energy X-ray absorptiometry (DXA) as a measure of body composition

Recent findings show that DXA is a highly reproducible measure of body composition in wheelchair athletes.

Lead academic:
Professor Vicky Tolfrey
Funder:
The Peter Harrison Foundation

In persons with a physical impairment such as a spinal injury, physiological and metabolic changes occur that both directly and indirectly affect body composition.

Muscle atrophy and a reduction in the cross sectional area of the muscle fibres occur largely as a result of muscle disuse. The assessment of body composition is a useful means of evaluating the effectiveness of nutritional strategies and training interventions designed to impact fat mass and fatfree mass. Determining DXA reproducibility among individuals with disability is necessary due to the vast body composition changes that occur, rendering able-bodied values impractical and without value. The purpose of this study was to determine the reproducibility of body composition measurements by DXA in elite athletes with a physical impairment.

Methods

12 elite male Wheelchair Basketball players (3 complete SCI>T5 / 1 incomplete T9-10 / 4 congenital spinal related injuries / 3 amputees / 1 club foot) participated in this study. Each participant underwent a whole body DXA scan which was repeated on the same day to assess total and regional body composition.

Main findings and applications 

  • Mean percentage body fat was 26.6±6.5%, which is comparable with previously reported data of highly trained athletes in the UK and worldwide.
  • Due to the large range of physical impairments, fat and lean tissue mass varied greatly.
  • There were some difficulties in positioning athletes due to scoliosis, curvature of the spine, inability to extend the knee, absence or abnormal anatomy of the lower limb landmarks.
  • DXA proved to be a highly reproducible measure of total and regional body composition of elite Wheelchair Basketball athletes.
  • DXA can detect individual changes in fat mass of at least 1 kg, lean tissue mass of 1.1 kg and bone mineral content of 0.12 kg.

Reference

Keil, M., Brooke-Wavell, K., Totosy de Zepetnek, J. and Goosey-Tolfrey, V.L. (2016). Measurement precision of body composition variables in elite wheelchair athletes, using dual-energy x-ray absorptiometry. European Journal of Sport Sciences. 16(1): 65-71. DOI: