William J. Tharion, Miyo Yokota, Mark J. Buller, James P. DeLany, Reed W. Hoyt
Med Sci Monit 2004; 10(9): CR504-509
Available online: 2004-09-01
Background: Total energy expenditure (TEE) assessment using pedometers provide an easy and less expensive method than doubly labeled water (DLW). This study assessed TEE by a new pedometry method (TEEpedo) compared to the doubly labeled water method (TEEdlw).
Material/Methods: Shipboard sailors (7 men, age: 23.0±3.9 yrs; ht: 180.2±6.5 cm; wt: 83.8±11.8 kg, and 10 women, age: 24.7±4.4 yrs; ht: 165.2±8.0 cm; wt: 63.5±14.0 kg) (Mean ±SD) were studied for 8 days. The energy cost of activity was estimated using (a) total body weight, (b) foot-ground contact times [Tc] during running, walking, and non-exercise activity [NEAT], and (c) the known proportion of time spent in each activity category. Resting metabolic rate (RMR) was estimated from lean body mass.
Results: TEEpedo was calculated as: TEEpedo (MJ) = (1440 × [%Run Time × ((0.0761 × [Total Body Weight/TcRun]) – 7.598) +%Walk Time × ((0.056 × [Total Body Weight/TcWalk]) – 2.938) + (%NEAT Time × 0.1 × [RMR/Minute])] + RMR)/239. This method, explained 79% of the variance of TEEpedo with a 95% confi dence interval of ±0.81 MJ/day, relative to TEEdlw (12.55±3.3MJ/day). Mean TEEpedo (12.65±3.1 MJ/day) did not differ from mean TEEdlw (p=0.95).
Conclusions: At TEEs >14 MJ/day, the TEEpedo method underestimated actual TEE, possibly due to unaccounted for upper body exercise. At more moderate TEEs of 9 to 14 MJ/day, the Tc pedometry method provided accurate estimates of TEE.
Keywords: Deuterium - metabolism, Energy Metabolism, Ergometry - instrumentation, Exercise, Exercise, Foot, Human Experimentation, Military Personnel, Oxygen Isotopes - metabolism, Regression Analysis, Deuterium - metabolism, Energy Metabolism, Ergometry - instrumentation, Exercise, Foot, Human Experimentation, Military Personnel, Oxygen Isotopes - metabolism, Regression Analysis