Exercising is a potent drug and we can't replicate it because it's not just one molecule. It's doing so much every single time you pound it, right? You're getting an endorphin raise, you're getting an immediate response to your vascular system. There's a psychological component when you do something that is difficult in the gym or on the track or in the pool or wherever you choose to get your exercise. Everything should be built around movement. They have schools with no P.E. now. And I think for me, the one thing I would probably change is institute a much more rigorous process of physical education and exercise from basically the times kids are born.