I've had a lot of shoulder issues in about 9 years of weight lifting and fixed almost all of them by finding and working on trigger points, often in...
You don't say where your back hurts, but when I've tweaked my lower back, stretching does make it go away, although it might take a couple of days.
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I've done both; I sometimes don't realize I have pain until after I start squatting. It doesn't hurt enough to stop, but it just causes a flinch as I...