Is carbohydrate loading necessary for endurance athletes?

For the endurance athletes, their performances are heavily dependent on having adequate supply of carbohydrate. Our body has a limited supply of carbohydrate compared to the amount of fat and protein. About 300-500 g of glycogen is stored in the muscles and another 75-100 g is stored in the liver (Bjorkman and Wahren, 1988). However, this amount is sufficient for us to run at moderate intensity for 20 miles (32 km)! An increase in exercise intensity will lead to an exponential increase in this utilization rate with the major contribution from muscle glycogen (Saltin and Karlsson, 1971).

It is not necessary for endurance athletes such as runners to engage in special dietary strategies such as carbohydrate loading during practices and races especially if the intensity is not high and the distance is relatively short.

References

Bjorkman, O., & Wahren, J. (1988). Glucose homeostasis during and after exercise. RL Terjung. New York: Macmillan, 100-115.

Saltin, B., & Karlsson, J. (1971). Muscle glycogen utilization during work of different intensities. In Muscle metabolism during exercise (pp. 289-299). Springer US.