Akuperma: Which rishon? What was the name of the book? Just wondering!
I don’t play or watch sports. I see nothing wrong with playing sports, since it is one good way to take care of our health (which may be easier to do consistently for some people because it’s more social and competitive than jogging or working out). Being sedentary takes years off one’s life, and also increases the risk of dementia and memory loss (for older people). So anything to give us regular exercise seems good.
Watching and following sports seems like an utter bitul zman, but I get the impression a lot of frum Jews do it anyway.