So not "into the outdoors" that you don't go outside? I think the point is find an environment that you are "into". Like being inside? Like being dry and listening to music while you lift weights or use the Stairmonster? Then do that, no shame, no excuses need be made.

But most people, my self included, don't particularly enjoy being in a gym (I'd rather run in a blizzard than on a treadmill, and my wife will tell you that she's witnessed my sincerity with her own eyes). I think the parent's point was, if you're not really "into the indoors", then don't go to the gym. If a gym suits you, then go do that.