Cold showers in the morning!! Unsure if it's scientifically proven. But there is abundance of literature if you Google for it. I've seen the results in myself

Cold showers in the morning!! Unsure if it's scientifically proven. But there is abundance of literature if you Google for it. I've seen the results in myself. From being a very passive in meetings, drowsy, and almost ADHD like behavior to being able to hold my focus and concentration till end of business and past. Key is doing it in the morning, evenings didn't work well.