Estimation of Energy Expenditure among Malaysian Young Adults: A Pilot Study Comparing Heart Rate Monitoring (HRM) Method and Activity Diary (AD) Method

Introduction: Accurate yet inexpensive methods for measuring free-living energy expenditure (EE) are much needed. The aim of this study was to determine the feasibility of heart-rate monitoring method (HRM) in measuring EE as compared to the established activity diary (AD) method. Methodology: Minute-by-minute HRM and an activity diary (AD) were used simultaneously in 34 young adults (18 females, 16 males; mean age 21.5 ± 1.5 years). Estimates of the EE from HRM were based on individual calibration using the Flex-HR procedure while EE from AD were calculated using both individually measured and published energy cost of various activities. Total daily energy expenditure (TDEE) and its components (EE during sleep, during rest and during physical activity) were compared using Student paired-t tests. Results: TDEE from HRM method averaged 8.17 ± 2.00 MJ/day compared to 8.50 ± 1.28 MJ/day from AD method. Although large intra-individual differences were found (ranging from -36.9% to 47.4%), there was no significant difference between the two methods (mean difference -3.6 ± 19.4%). The limits of agreement (mean ± 2SD) were -3.77 and 3.11 MJ/day. There were no significant differences for any of the TDEE components between the two methods, except for EE during sleep (p 0.05). Conclusion: HRM method was found to be a feasible method for assessment of EE, and was comparable to AD for group assessment of TDEE and its components.