Hmmm, I might skip the workout - you wouldn't want to pinch/irritate things more than they already are.
When it happens to me, I have FH use his thumb and index finger and very firmly slide them up either side of my spine a couple times to loosen things up. Then I'm able to squeeze my shoulder blades together enough to get it to pop. I've used a desk/wall corner before though if he wasn't around - sometimes it works, sometimes not.
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To be yourself in a world that is constantly trying to make you something else is the greatest accomplishment ~ {Ralph Waldo Emerson}
You know what works for me? This is going to sound equally weird:
My DH lays faceup on the floor and lay on top of him faced down. He puts his arms around me and puts his fist along my spine where I need the the crack and he squeezes really quick. It ALWAYS works for me and it feels really good. Maybe it will work for you?