Investigating the clinical significance of fasting prior to body composition measurements using air displacement plethysmography

Item

Title
Investigating the clinical significance of fasting prior to body composition measurements using air displacement plethysmography
Author(s)
Themistocleous Eva Vathoulla
Abstract
ABSTRACT
Objective - To investigate the clinical significance of fasting prior to body composition measurements using air displacement plethysmography.
Design - Repeated measurements of body volume and derived body composition using the BOD POD measurement system were performed. Measurements of body volume and derived body composition pre and post prandially were also performed. Influence of food composition on body density and hence derived % body fat (BF) was also investigated.
Subjects - A heterogeneous sample of thirty one healthy adults (16 males, 15 females) who ranged in age between 22-56 yrs and in BMI between 17.0-31.9kg/m2.
Method - Subjects were asked to fast for a 12hr period overnight and measurements were conducted using the BOD POD. Prior to the second test the subjects consumed 500grams of food. There was a 15 min gap between measurements. Testing was performed in the morning not long after the subject's awakening.
Results - Repeat measurements showed no significant difference in measurements of volume (P=0.087) density (P=0.503) of %BF (P=0.531). Repeat measurements of raw body volume in human subjects resulted in a technical error equivalent to 1.2% BF. Pre and Post measurements showed a significant difference in mean volume (P<0.001), body weight (P<0.001), % BF (P=0.013). The difference in % mean BF derived pre to post prandially was more significant in males (P<0.001) than in females (P=0.895).Pre to post measurements of mean body volume resulted in a technical error of 1.5% body fat. Increased fat intake in the food consumed correlated significantly (r = 0.362 P=0.05) to an increase in volume change therefore a high fat content in food intake did affect the pre to post measurements.
Conclusion - If there was a tendency to overestimate %BF in the subjects after they had just eaten, this was not governed by the composition of food. The independent effects of food only equated to a relatively small variability. The magnitude of error between pre and post-prandial measurements was only slightly higher than the repeatability error of the BOD POD therefore for practical purposes fasting can be disregarded and double measurements could be performed. Although the BOD POD ADP measurements are a simple procedure to perform, it is important to emphasise the complex interplay of environmental, physiological, and anatomical factors, which lie behind the procedure, attributing to variability of the final outcome.
This study is a showcase for the validation of any methodology and the quantification of variability within the methodology in question.
Ms V Themistocleous. Investigating the clinical significance of fasting prior to body composition
measurements using air displacement plethysmography.
Suggestions for further research:
A larger sample population could be used and also specific gender studies could be conducted with larger subject groups of males and females, to clarify and confirm the bias observed within this research.
Methodological issues could be more controlled and monitored throughout future research: SAA measurement, skin temperature. could be some of variables investigated.
An investigation looking at lean individuals versus obese, to confirm the possible effect on derived %BF measurements.
To complement this study more investigation could be conducted regarding the effect of fat composition consumed on the mean volume measurements.
Fasting may be disregarded for cross sectional studies when measuring one group population but once comparison is made between different group populations or longitudinal measurements in a single individual, consistency is necessary therefore fasting the subjects would be essential.
Ms V Themistocleous. Investigating the clinical significance of fasting prior to body composition measurements using air displacement plethysmography.
presented at
British College of Osteopathic Medicine
Date Accepted
0
Date Submitted
1.1.1970 00:00:00
Type
osteo_thesis
Language
English
Submitted by:
62
Pub-Identifier
13609
Inst-Identifier
1076
Recommended
0
Item sets
Thesis

Themistocleous Eva Vathoulla, “Investigating the clinical significance of fasting prior to body composition measurements using air displacement plethysmography”, Osteopathic Research Web, accessed April 23, 2025, https://library.wso.at/s/orw/item/1148