Total Energy Expenditure Estimated using a Foot-Contact Pedometer

摘要

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). Subjects were shipboard sailors (7 men, ages 23.0 +/- 3.9 years, height 180.2 +/- 6.5 cm, and weight 83.8 +/- 11.8 kg) and 10 women (ages 24.7 +/- 4.4 years, height 165.2 +/- 8.0 cm, and weight 63.5 +/- 14.0 kg) (Mean + SD ), who were studied for 8 days. The energy cost of activity was estimated using the following: (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. TEEpedo was calculated as TEEpedo (MJ) = (1440 x %Run Time x ((0.0761 x Total Body Weight/TcRun) - 7.598) + % Walk Time x (0.056 x Total Body Weight/TcWalk) - 2.938) + (%NEAT Time x 0.1 x RMR/Minute) + RMR)/239. This method explained 79% of the variance of TEEpedo with a 95% confidence 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). The authors conclude that at TEEs greater than 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. (2 tables, 3 figures, 21 refs.).