It could be a simple lifestyle that makes you "fit" (lots of walking, working a not-too-demanding physical job, a physical hobby, biking around...).
The parent post is saying that technological advance has removed the need for physical activity to survive, but all of the gym rats have come out of the woodwork to complain how we are all going to die if we don't hit the gym, pronto.
It could be a simple lifestyle that makes you "fit" (lots of walking, working a not-too-demanding physical job, a physical hobby, biking around...).
The parent post is saying that technological advance has removed the need for physical activity to survive, but all of the gym rats have come out of the woodwork to complain how we are all going to die if we don't hit the gym, pronto.