Abstract
Objective: The contribution of basal metabolic rate (BMR) to weight gain susceptibility has long been debated. We wanted to examine whether BMR changes in a linear fashion with overfeeding. Our hypothesis was that BMR does not increase linearly with 1000-kcal/d overfeeding in lean healthy subjects over 8 weeks. The null hypothesis states that BMR increases linearly with 1000-kcal/d overfeeding in lean healthy subjects. Research Methods and Procedures: Initially, 16 lean healthy sedentary subjects completed 2 weeks of weight maintenance feeding at the General Clinical Research Center. The subjects were then overfed by 1000 kcal/d over 8 weeks. BMR was measured under standard conditions each week using indirect calorimetry. Results: Baseline BMR was 1693 ±154.5 kcal/d. BMR increased from 1711 ±201.3 kcal/d at week 1 of overfeeding to 1781 ±171.65 kcal/d at the second week of overfeeding (p = 0.05). BMR fell during the third week of overfeeding to 1729 ±179.5 kcal/d (p = 0.05). After 5 weeks of overfeeding, BMR reached a plateau. Thereafter, there was no further change. Comparison of BMR with weeks of overfeeding was significantly different compared with the linear model (p < 0.05). Discussion: Increases in BMR in lean sedentary healthy subjects with 1000-kcal/d overfeeding are not linear over 8 weeks. There seems to be a short-term increase in BMR in the first 2 weeks of overfeeding that is not representative of longer-term changes.
Original language | English (US) |
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Pages (from-to) | 690-695 |
Number of pages | 6 |
Journal | Obesity |
Volume | 14 |
Issue number | 4 |
DOIs | |
State | Published - Apr 2006 |
Externally published | Yes |
Keywords
- Basal metabolic rate
- Energy metabolism
- Indirect calorimetry
- Overfeeding
ASJC Scopus subject areas
- Medicine (miscellaneous)
- Endocrinology, Diabetes and Metabolism
- Endocrinology
- Nutrition and Dietetics