Validity Of B-mode Ultrasound For Body Composition Assessment In The Field

Abstract

Shane Draper, Nate Jensen, Conner Dearden, Brett Holmes, Andrew Creer Utah Valley University; Orem, UT Air displacement plethysmography (ADP) is a common way to assess athlete body composition in many laboratories. While this method provides accurate values for body composition, it is not a feasible option for field work. Identifying an accurate, user friendly alternative to skinfold calipers may allow for accurate assessment of body composition in more applied settings, such as various training and competition venues. PURPOSE: To determine the validity of B-mode ultrasound (BMUS) for body composition assessment by comparing this method to values obtained using ADP. METHODS: Twenty actively training runners (≥ 4 hours/week for 12 months) have participated in this study. Participants (37.5 ± 10.2 yrs; 173.2 ± 9.8 cm; 69.4 ± 12.5 kg) included males (n = 12) and females (n = 8) that have undergone two forms of body composition assessment during a single lab visit; ADP and BMUS. ADP body density was estimated using an air displacement chamber (BodPod, COSMED USA Inc.) in combination with measured lung volume. BMUS body density was estimated from measuring the Jackson-Pollock 7 site skinfolds with a portable, app-based ultrasound device (Lumify, Philips) to determine subcutaneous fat thickness. Images were then analyzed using proprietary software (MuscleSound, Glendale, CO). Body density values for both methods were converted to body fat percentage using the Siri equation. A paired samples t-test was used to compare values obtained from ADP and BMUS. RESULTS: There was no difference between ADP (18.7 ± 7.1%) and BMUS (17.7 ± 7.8%; p = 0.2) for percent body fat. In addition, data analysis revealed a strong positive correlation (R = 0.91) for percent body fat obtained from ADP and BMUA methods. CONCLUSION: These data suggest BMUS is a valid method for assessing body composition when compared to ADP, and therefore provide a portable, accurate method for assessing body composition in applied settings.