In that the content of meals consumed after exercise can impact metabolic responses for hours and even days after the exercise session, Jeffrey F. Horowitz, from the University of Michigan (USA), and colleagues compared the effect of low dietary carbohydrate versus low energy intake in meals after exercise on insulin sensitivity and lipid metabolism the next day.  Enrolling nine healthy sedentary men, ages 28-30 years, each spent four separate sessions in the study, prior to which they  fasted overnight before attending each session,.  The four visits each involved varied combinations of exercise and post-exercise meals.  In the three sessions involving exercise, the researchers found a trend for an increase in insulin sensitivity. However, when participants ate less carbohydrate after exercise, this enhanced insulin sensitivity significantly more.  The team concludes that: “Carbohydrate deficit after exercise, but not energy deficit, contributed to the insulin sensitizing effects of acute aerobic exercise. Whereas maintaining an energy deficit after exercise augmented lipid mobilization.”