title: Prediction of twenty-four-hour energy expenditure in a respiration chamber in smokers and non-smokers.
abstract: Fourteen subjects (seven smokers, seven non-smokers) underwent at least one measurement of 24-h energy expenditure (EE) in a respiration chamber, smoking or not smoking as normal. Activity levels (AL) were calculated as multiples of basal metabolic rate (BMR) from records of time spent in specified activity categories and their average published energy costs. Predicted 24-h EE was estimated by multiplying AL by BMR measured on exit from the chamber. Smokers smoked an average of 18.6 cigarettes during the 24-h EE measurement (range 9-29). Measured 24-h EE was higher than predicted in the smokers (7.1%, P < 0.001) but not significantly different from predicted in the non-smokers (2.6% lower). We conclude that smoking increases 24-h EE and that factorial prediction of EE using average published energy costs of activities under-estimates 24-h EE in smokers but not in non-smokers.
authors.affiliation: Department of Biochemistry, Microbiology and Nutrition, University of New England, Armidale, NSW, Australia.
authors.forename: P M
authors.initials: PM
authors.lastname: Warwick
authors.forename: R
authors.initials: R
authors.lastname: Busby
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D001481:Basal Metabolism; D001835:Body Weight; D004734:Energy Metabolism; D005069:Evaluation Studies as Topic; D015444:Exercise; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D008433:Mathematics; D011237:Predictive Value of Tests; D012129:Respiratory Function Tests; D012907:Smoking / Q000378:metabolism*