Carbohydrates
Glycogen and stress are very tightly correlated.
Since intense endurance exercise invariably leads to glycogen depletion, which in turn leads to elevation of cortisol, the best way to manage stress during exercise is with proper fueling.
In simple terms, that means you have to consume carbohydrates. And the best way to do that during exercise is by using an energy gel or an isotonic sports drink.
Ashwagandha
Adaptogens are well known for their ability to improve VO2 max and reduce stress levels.
If you're looking for a single adaptogen to help you manage stress, look no further than ashwagandha, the most powerful adaptogen.
Zinc
Zinc is a mineral directly correlated to stress. In fact, zinc helps you to sustain the health of your nervous system.
For this reason, supplementing zinc is a great way to manage your cortisol levels.