The relationship between body fat percentage and difference in caloric expenditure as measured by indirect calorimetry and estimated by an elliptical trainer


A. Page Glave, Jennifer J. Didier, Gary L. Oden, Matthew C. Wagner, Stevyn M. Rivera

Objective: This study examined the effects of increased body fat percentage on the difference between estimated and measured caloric expenditure. Materials and Methods: In total, 34 adults participated in the study. The exercise was completed on an elliptical machine for 30 min: 5 min warm-up, 20 min exercise at 64-76% of maximum estimated heart rate, and 5 min cool-down. Indirect calorimetry was measured and recorded every 5 min along with ratings of perceived exertion. Heart rate was monitored throughout the exercise session. Body composition was measured using BodPod. Analysis was completed using SAS 9.4 to calculate the correlation between the difference at each time point and body fat. Results: No significant relationships between body fat and the difference in caloric estimate overall or at any time point (P = 0.06-0.10) were found. There was a consistent negative correlation between body fat and caloric estimate difference (−0.31 overall, −0.24 to −0.36 for the intermediate time points). No significant differences in caloric estimates based on obesity classification were found. Conclusions: Individuals with lower body fat percentage need to be cautious when relying on caloric estimates from exercise equipment, and those who near their weight goal will be less able to rely on the caloric estimates from exercise equipment. It is important to enter as much information as possible for increased accuracy when using an exercise machine.