If you’re worried about the catabolic effects of cortisol, make sure to drink carbohydrate during exercise.
Cortisol is known as a stress hormone. Although it has many roles in your body, one of its main functions is to break down muscle and burn it for energy. In short, if you’re trying to build more muscle, a lot of cortisol isn’t a good thing!
Now, Japanese researchers have shown that when blood sugar levels drop during exercise, cortisol levels go UP! However, when blood sugar levels are maintained (which you can achieve by drinking a carbohydrate drink during exercise), cortisol levels remain normal.
However, it’s important that you mix up your carbohydrate drink correctly:
1. A simple rule of thumb is to add one scoop of a carbohydrate drink (such as Viper) to a 500 ml water bottle. This gives you the correct 8% isotonic solution, which is ideal for rehydration and reducing cortisol levels. Only use a stronger solution after training (when you need recovery) after training, otherwise your performance will be impaired and you may cramp up.
2. Don’t use carbohydrate drinks containing only fructose. Current studies show that both glucose and maltodextrin are the best way to maintain blood-sugar levels during exercise. However recent research has indicated that a combination of glucose and fructose can help performance during long duration exercises of aroun d2-3 hours.
Tabata, I., Ogita, F., Miyachi, M., & Shibayama, H. (1991). Effect of low blood glucose on plasma CRF, ACTH, and cortisol during prolonged physical exercise. Journal of Applied Physiology, 71, 1807-1812