Prediction #3: Gymnastics will begin in the nursery, where toys and games will be designed to strengthen the muscles. Exercise will be compulsory in the schools. Every school, college and community will have a complete gymnasium. All cities will have public gymnasiums. A man or woman unable to walk ten miles at a stretch will be regarded as a weakling.
More or less a hit on the prevalence of gyms, total miss on the ramifications!
2. Not only do colleges and universities have complete gymnasiums, many of them have enormous staudiums and fields.
The one miss that I do agree with is "A man or woman unable to walk ten miles at a stretch will be regarded as a weakling."
I expect PE to be uncommon some time soon-ish. Besides, PE is too hard when you're fat.
We often forget that America and Britain were very much in love with Eugenics. Unfortunately that is probably not something included in the high-school history curriculum...
Search for footage of the controversial "Olympia" by Leni Riefenstahl it typifies the mood and the idea...