How relevant is the GI for athletes?
The GI can be a useful tool to help athletes select the right type of carbohydrates to consume both before and after exercise. Studies have consistently reported that a low GI pre-exercise meal results in a better maintenance of blood glucose concentrations during exercise and a higher rate of fat oxidation. This is likely to result in reduced muscle glycogen utilisation during prolonged exercise and possibly improve endurance performance. Eating high GI meals before exercise may result in plasma glucose concentrations peaking before the onset of exercise and then hypoglycemia occurring within the first 30 minutes of the exercise period. There is little data available on the effect of the GI of carbohydrates eaten before intermittent, power or strength related sports. During recovery from exercise, muscle glycogen resynthesis is of high metabolic priority. The eating of high GI carbohydrates after exercise increases plasma glucose and insulin concentrations and this facilitates muscle
