Is bioelectrical impedance spectroscopy accurate in estimating changes in fat-free mass in judo athletes?
Bioelectrical impedance spectroscopy (BIS) provides an affordable and practical assessment of fat-free mass (FFM). However, little information is available on the assessment of changes in fat-free mass in top-level athletes using BIS. The aim of this study was to examine the accuracy of BIS in tracking changes in fat-free mass of elite male judo athletes from a period of weight stability to just before competition, using the four-compartment model (4C model) as reference method. In total, 27 elite male judo athletes (age 22.2 ± 2.8 years) were evaluated. Measures of body volume assessed by air displacement plethysmography, bone mineral content by dual-energy X-ray absorptiometry, and total-body water assessed with deuterium dilution were used in a 4C model. Fat-free mass was also assessed by BIS (FFM(BIS)). Changes in FFM(BIS) were not significantly different from measured by the reference method (P = 0.000). Furthermore, the r² was 0.62 and the standard error of the estimate was 1.03 kg. The limits of agreement ranged from -3.36 to 2.59 kg with no bias observed. These findings demonstrate the viability of BIS as a valid tool for tracking fat-free mass in elite male judo athletes. However, based on the wide limits of agreement observed, BIS is less valid at an individual level for tracking fat-free mass in these athletes.
Exercise and Health Laboratory, Faculty of Human Kinetics, Technical University of Lisbon, Cruz-Quebrada, Portugal.
Catarina N
CN
Matias
Diana A
DA
Santos
David A
DA
Fields
Luis B
LB
Sardinha
Analiza M
AM
Silva
D000328:Adult; D056352:Athletes; D001823:Body Composition; D001825:Body Fluid Compartments; D058266:Dielectric Spectroscopy / Q000379:methods*; D017097:Electric Impedance; D006801:Humans; D008297:Male; D016139:Martial Arts; D015203:Reproducibility of Results; D055815:Young Adult