Effect of the preceding day's energy intake on the energy costs of rest, arm and leg exercise.

Relatively little is known about the response of the human body to perturbations in the energy intake. In particular, results of the effect of a perturbation of the preceding day's energy intake on the energy expenditure on the following day are conflicting, ranging from no effect at all to an increase in the resting metabolic rate of 12 per cent following an increase in the preceding day's energy intake of 5 MJ. In the present study, the fasting energy expenditure of rest, light arm work and light leg work was determined on days following an intake of 4, 10 and 16 MJ in seven healthy men. In each subject, the difference in energy expenditure between days following intakes on the preceding day of 10-10 (control), 10-4 and 10-16 MJ was calculated for each of the three tasks. The mean percentage differences between the days following an intake of 10-10, 10-4 and 10-16 MJ were (s.d. in parenthesis) 0.0 (4.0), +1.3 (4.0) and +0.6 (3.2) for the resting metabolic rate, -1.7 (4.0), -2.2 (3.2) and -1.7 (3.7) for arm work and +0.3 (2.0), -1.2 (2.9) and -0.3 (3.2) for leg work. When the differences for the three tasks were averaged, the results were -0.5 (1.4), -0.7 (2.4) and -0.5 (1.3) for the three combinations respectively. None of these differences were found to be statistically different from zero. Changes in plasma adrenaline and noradrenaline concentrations were also measured but found not to be related to the changes in energy expenditure or to the energy intakes.(ABSTRACT TRUNCATED AT 250 WORDS)