This transference of emotions is very powerful, especially knowing that laughter is the best medicine. One time, I recall feeling ill, then after a roll of laughter that lasted for more than 5 minutes, I felt much better. I was literally cured of my illness because of laughter.

This is just my opinion, but from my experience in doing long walks and jogging at least 30 minutes everyday, laughing and prolonged exercise has similar effects. I feel the same goodness inside after laughing for many minutes and after a long exercise. No wonder we hear stories about people with severe diseases who miraculously heal after watching hours of funny videos.