Postexercise energy expenditure and substrate oxidation in young women resulting from exercise bouts of different intensity

• Published in: Journal of the American College of Nutrition 1997-04, Vol.16 (2), p.140-146
• Main Authors: Phelain, J.F. (Colorado State University, Fort Collins, CO.), Reinke, E, Harris, M.A, Melby, C.L
• Format: Article
• Language: English
• Subjects: ACTIVIDAD FISICA; ACTIVITE PHYSIQUE; Adult; Biological and medical sciences; Calorimetry; CARBOHIDRATOS; Carbohydrate Metabolism; CARBOHYDRATES; CONSOMMATION D'OXYGENE; CONSUMO DE OXIGENO; CORPS GRAS; ENERGIA; ENERGIE; ENERGY; Energy Metabolism; Exercise; FATS; Fats - metabolism; Female; Fundamental and applied biological sciences. Psychology; GLUCIDE; GRASAS; HIGH INTENSITY EXERCISE; Humans; Intermediate and energetic metabolism; LOW INTENSITY EXERCISE; Metabolisms and neurohumoral controls; Oxidation-Reduction; Oxygen - metabolism; OXYGEN CONSUMPTION; PHYSICAL ACTIVITY; Vertebrates: anatomy and physiology, studies on body, several organs or systems
• ISSN: 0731-5724; 1541-1087
• DOI: 10.1080/07315724.1997.10718664

Objective: The effects of low and high intensity exercise, of similar energy output, on exercise and post-exercise energy expenditure and substrate oxidation were studied in eight active, eumenorrheic females (aged 22 to 31). Methods: Continuous indirect calorimetry was performed during cycle ergometry exercise and for 3 hours following each of the following three protocols administered in random order: (1) low intensity exercise (LIE: 500 calories 50% VO2 max), (2) high intensity exercise (HIE: 500 calories 75% VO2 max), and (3) control condition (C) of quiet sitting for 1 hour, rather than exercise. Excess postexercise oxygen consumption (EPOC), energy expenditure and total fat and carbohydrate oxidation for the entire exercise/control plus 3-hour recovery period were determined by indirect calorimetry. Results: Mean EPOC for the 3-hour post-exercise period for HIE (9.0 + 1.7 L, 41 kcals) was significantly greater than EPOC for low intensity exercise (4.8 +/- 1.6 L, 22 kcals). Oxygen consumption (VO2) following HIE, but not LIE remained elevated at the end of the 3-hour post-exercise period. Total carbohydrate oxidation (exercise plus postexercise period) was significantly higher for HIE (116 +/- 8.6 g) compared to HIE (85.0 +/- 5.2 g). Total fat oxidation was lower for HIE (27.7 +/- 3.3 g) compared to HIE (36.9 +/- 3.0 g), but this difference did not reach statistical significance (p = 0.07). At the end of the 3-hour recovery period, the rate of fat oxidation was higher following HIE compared to LIE. Conclusion: These data indicate that the recovery period should also be considered when determining the impact of different exercise intensities on total energy expenditure and fat and carbohydrate utilization in women