Abstract
Hormonal-induced water retention during the menstrual cycle (MC) may affect the estimates of body composition (BC) parameters depending on the MC phase if tissue hydration or volume is part of the BC analysis equations. Given this, MC phase-dependent changes of BC parameters might be expected within females for bioelectrical impedance analysis (BIA) or air-displacement plethysmography (ADP), whereas skin-fold calipometry (CAL) might not be affected. This study aimed to evaluate BC analyses during a regular MC by means of BIA and ADP with CAL serving as a control method in females with or without hormonal contraception with males serving as a control group. In a case-control design with repeated measurements, BC was determined using BIA, ADP, and CAL in 54 participants (age 18-33; BMI 17.0-27.8) divided into females using hormonal contraceptives (HC) (n = 19), females using no-hormonal contraceptives (no-HC) (n = 17), and males (n = 18). BC was assessed on four cycle-related days (menstruation, late follicular, ovulation, and late luteal). There were only small intraindividual BC variations during the MC (CV% 0.5-5.2) and neither significant time effects within any group (p = 0.065-0.939) nor significant time*group interactions (p = 0.151-0.956) for all devices (BIA, ADP, CAL) in any BC parameter. The results indicate that hormonal-induced water retention, if any, during MC had no effect on BC estimates of ADP, BIA, and CAL or were too small to be identified neither in females with HC nor in females with no-HC.