Twenty-four-hour energy expenditure and resting metabolic rate in obese, moderately obese, and control subjects

Am J Clin Nutr. 1982 Mar;35(3):566-73. doi: 10.1093/ajcn/35.3.566.

Abstract

Twenty-four-hour energy expenditure (24-EE), resting metabolic rate (RMR) and body composition were determined in 30 subjects from three groups; control (103 +/- 2% ideal body weight, n = 10), moderately obese (129 +/- 1% ideal body weight, n = 6), and obese (170 +/- 5% ideal body weight, n = 14) individuals. Twenty-four EE was measured in a comfortable airtight respiration chamber. When expressed as absolute values, both RMR and 24-EE were significantly increased in obese subjects when compared to normal weight subjects. The RMR was 7592 +/- 351 kJ/day in the obese, 6652 +/- 242 kJ/day in the moderately obese, and 6118 +/- 405 kJ/day in the controls. Mean 24-EE values were 10043 +/- 363, 9599 +/- 277, and 8439 +/- 432 kJ/day in the obese, moderately obese, and controls, respectively. The larger energy expenditure in the obese over 24 h was mainly due to a greater VO2 during the daylight hours. However, 92% of the larger 24-EE in the obese, compared to the control group, was accounted for by the higher RMR and only 8% by other factors such as the increased cost of moving the extra weight of the obese. The higher RMR and 24-EE in the obese was best related to the increased fat free mass.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Basal Metabolism*
  • Body Composition
  • Carbon Dioxide / blood
  • Circadian Rhythm
  • Energy Metabolism*
  • Fatty Acids, Nonesterified / blood
  • Female
  • Humans
  • Male
  • Middle Aged
  • Obesity / blood
  • Obesity / metabolism*
  • Sleep / physiology

Substances

  • Fatty Acids, Nonesterified
  • Carbon Dioxide