ZHANG, K., F. X. PI-SUNYER, and C. N. BOOZER. Improving Energy Expenditure Estimation for Physical Activity. Med. Sci. Sports Exerc., Vol. 36, No. 5, pp. 883–889, 2004.
The purpose of this study was to validate the Intelligent Device for Energy Expenditure and Activity (IDEEA) for estimation of energy expenditure during a variety of activities. An additional aim was to improve the accuracy of the estimation of energy expenditure of physical activity based on second-by-second information of type, onset, and duration of activity.
This study included two tests: a mask calorimetry test with 27 subjects [age = 33.7 ± 13.8 (mean ± SD) yr; BMI = 24.8 ± 4.8 kg·m−2] and a respiratory chamber calorimetry test with 10 subjects (age = 32.9 ± 12.4 yr; BMI = 26.1 ± 5.6 kg·m−2). In the mask test, the subjects performed activities (sitting, standing, lying down, level treadmill walking, and running at different speeds) for 50-min durations. For the chamber test, subjects lived in the metabolic chamber for 23 h and performed three exercise sessions to compensate for the confined environment.
The results showed significant correlations (P < 0.0001) between energy expenditure estimated by IDEEA and energy expenditure measured by the calorimeters with an accuracy >95%. After corrections for the decrease in sleeping metabolic rate, the estimation accuracy for the chamber test was increased by 1–96.2%, whereas the estimation accuracy for nighttime activity was significantly improved by 4–99%.
IDEEA provides a suitable method for estimating the energy expenditure of physical activity. It provides both instantaneous and cumulative estimates of energy expenditure over a given period.
NY Obesity Research Center, St. Luke’s-Roosevelt Hospital and Institute of Human Nutrition, Department of Medicine, Columbia University, New York, NY
Address for correspondence: Kuan Zhang, Ph.D., NY Obesity Research Center, St. Luke’s-Roosevelt Hospital Center, 1111 Amsterdam Avenue, New York, NY 10025; E-mail: email@example.com.
Submitted for publication July 2003.
Accepted for publication December 2003.