It's called "runners high", and true maybe not in the beginning, because we're all different, but we're also all the same, and over the course of a lifetime, the odds are in favor of you eventually experiencing it. Realistically, I only get it about 20% of the time I go out and the other 80% of the time, am relying on the knowledge that I'm doing good for my body.
replyIf in five years of strenuous exercise, four days a week, for ~30 weeks a year, along with significant exercise for 20 of the other 22 weeks a year, I never once experienced anything like it, I'd say that the odds are as close to zero as they could meaningfully be.
replyNot to mention riding a bicycle as my only mode of transportation other than foot for ten years before I had a driver's license.
I enjoyed tackling people. I did not enjoy the exercise itself and would not have done it if I could have skipped right to the games without having done all that other stuff.