There is one piece of playground equipment in particular. I think it's called the spinner? It's hard to find any more, as they're clearly death traps. When I was little, the spinner was a large round platform about a foot off the ground with several metal rails on it that you were supposed to hold onto for balance. The less popular kids (I think this is how it was decided?) had to hold the outer legs of the metal rails and run in the inevitable mud around the spinner until it got some good momentum going, and then jump on and enjoy the vertigo-inducing spin, holding on tight or risking being flung right back off, as the outer edge was the riskiest place to be but the momentum made it hard to move inward once the spinner was in motion. If you were already on the spinner as it was being spun faster and faster, your job was to stay on and not vomit, which was easier if you were towards the center of the thing, and had not just drunk your chocolate milk ration too quickly. Ah, childhood.
There's a modern version of the spinner now, a one-person deal, which I find excellent as I do not and never have played well with most others. This version is a pole in the ground, slightly tilted with a one-person platform for standing. It involves just one good kick off the ground to get it started, since you're only pushing for one person. It starts to whirl pretty fast and all you have is the one pole to hang on to. The instinct is to hold on really, really tightly, because it feels like everything about this innocent-looking playground thing wants to hurl you directly off of it.
But here's what's funny: if you almost let go, if you open yourself to the wind whipping at you, if you go so far as to fling out your arm and leg, counting on just one hand to hold you in place ... it slows down. It stops feeling so damn scary. The magic that made the inner circle feel safe on the spinner of your childhood is the same magic physics that makes it such that when you are alone, the best way to stay upright is to spread out, open yourself up, even though it really feels like the safest thing to do is shrink and cling.
Which is not a metaphor for anything.