PURPOSE: The purpose of this investigation was to quantify the effects of different attire on the accuracy and reliability of estimating percent body fat (%fat) by using air displacement plethysmography (ADP). METHODS: Fifteen adults were tested four times on four separate occasions. Each session consisted of estimating %fat with ADP wearing a swimsuit (ADP(SS)), a hospital gown (ADP(HG)), and in the nude (ADP(N)), plus assessment by hydrostatic weighing (HW). RESULTS: An ANOVA revealed no significant differences within any of the four methods over the 4 days. Intraclass correlation coefficients revealed a strong relationship for repeated measures in ADP(SS) (r = 0.981), ADP(HG) (r = 0.993), ADP(N) (r = 0.989), and HW (r = 0.976). Mean data for each condition indicated a significant underestimation (P < 0.05) of %fat while wearing a hospital gown (13.8 +/- 7.7%) compared with ADP(SS) (22.0 +/- 7.8%), ADP(N) (23.5 +/- 7.5%), and HW (22.6 +/- 6.8%). CONCLUSION: Reliability of ADP does not appear to be compromised by clothing; however, wearing a hospital gown significantly affects accuracy, reducing %fat estimations by approximately 9% compared with the recommended swimsuit. Measurement in the nude does not provide more reliable or accurate measures than wearing a swimsuit.
PURPOSE: The purpose of this investigation was to quantify the effects of different attire on the accuracy and reliability of estimating percent body fat (%fat) by using air displacement plethysmography (ADP). METHODS: Fifteen adults were tested four times on four separate occasions. Each session consisted of estimating %fat with ADP wearing a swimsuit (ADP(SS)), a hospital gown (ADP(HG)), and in the nude (ADP(N)), plus assessment by hydrostatic weighing (HW). RESULTS: An ANOVA revealed no significant differences within any of the four methods over the 4 days. Intraclass correlation coefficients revealed a strong relationship for repeated measures in ADP(SS) (r = 0.981), ADP(HG) (r = 0.993), ADP(N) (r = 0.989), and HW (r = 0.976). Mean data for each condition indicated a significant underestimation (P < 0.05) of %fat while wearing a hospital gown (13.8 +/- 7.7%) compared with ADP(SS) (22.0 +/- 7.8%), ADP(N) (23.5 +/- 7.5%), and HW (22.6 +/- 6.8%). CONCLUSION: Reliability of ADP does not appear to be compromised by clothing; however, wearing a hospital gown significantly affects accuracy, reducing %fat estimations by approximately 9% compared with the recommended swimsuit. Measurement in the nude does not provide more reliable or accurate measures than wearing a swimsuit.