Let it be known that I think running in humans is necessary for a human to be normal.
In science there is nothing wrong with such an assumption as long as the mind is kept open for evidence to verify such a statement or to refute it. The reasons for belief are interesting in themselves as is the science that explores questions and finds answers. There have to be enough evidence to make a position worth exploring. Here then is, in my opinion, why and and the how to determine the validity of the statement, "humans must exercise as much as running provides to be normal." The question arises, are human non-runners either abnormal or subnormal?
What if statistics indicate that runners rarely get Alzheimer's as has been reported and that runners live on an average of two to two and a half years linger than do non-runners as has been reported? And what if problems without published causes such as ALS, MS, Cystic Fibrosis, Parkinson's and other problems are shown to be rarely found in runners, would science be interested in searching for why?
I suggest a crash program of statistical analysis be undertaken immediately to determine if running is the answer to such important tragic maladies of so many humans. A friend of mine who was perhaps the last person Dr. Kovorican helped end her life had Parkinson's and did not want the lingering disease before normal death. The haunting question I personally have over her early death is, "what if she had been a runner?" I have a guilty conscience over believing about the need of running in humans that if known by others would save unbelievable unnecessary suffering not with drugs but with running.