Or even the "high" of being in such great physical shape that you know you can run all day long...even in 90 degree heat and 90% humidity. I'm wondering if the "ultimate" high can actually be achieved without the use on any drugs or stimulants. I think proper diet goes a long way towards creating a "natural" high also. It's very tuff to break bad habits, so small gains and steady progress is the way I try to approach things. :-)