Ashwaganda. You can take it in supplement form. Be conservative with your salt intake. Lifting. Cortisol is a stress hormone, so it's basically what drives you to get up and do shit, and even wake up from sleeping. It tends to spike in the morning. Sunlight stimulates cortisol production. It's important to keep in mind that it's not all bad. Very low cortisol levels will make you apathetic and less responsive to the environment around you. Further, the mechanisms surrounding speech and stuttering are much more complex. Cortisol only plays a part in it.