From Bill Hartman:
You'll get hurt if you do not move at all, not move in the wrong position, or move wrongly. And you'll get hurt anyway as you age as you're, um, aging. That's why I laugh when sedentary people (who complain of aches and pains anyway) decide to remain sedentary because they're "afraid to get hurt".
Just get up and moving, hopefully in a correct and safe manner, and just do your best.