Effect of short-term energy intake level and exercise on oxygen consumption in men

Summary

The influence of short-term energy intake and cycle exercise on oxygen consumption in response to a 1.5 MJ test meal was investigated in ten young, adult men. On the morning after a previous day's “low-energy“ intake (LE regimen) of 4.5 MJ, the mean resting oxygen consumption increased by 0.7 ml · kg⁻¹ · min⁻¹ after the test meal (P<0.025). After a “high-energy“ intake (HE regimen) of 18.1 MJ, the resting measurement was unchanged (+0.4 ml · kg⁻¹ · min⁻¹) after the meal (n.s.). These trends are the reverse of what would be expected if oxygen consumption in response to feeding is a factor in the acute control of body weight. The mean fasting oxygen consumption during cycle exercise at 56% of$\dot V_{O_{2max} }$ (constant work) for both LE and HE prior intakes was not different at 31.1 ml · kg⁻¹ · min⁻¹. Oxygen consumption during exercise increased after feeding by 0.5 ml · kg⁻¹ · min⁻¹ on the LE regimen (n.s.) and decreased by 1.2 ml · kg⁻¹ · min⁻¹ on the HE regimen (n.s.). These results are also the reverse of what would be expected if oxygen consumption in response to exercise is related to short-term energy intake.