I know what it is and what it does but could it cause old pulled muscle injuries to flair up? For 10+ years I've had calf issues in both legs from either micro tears or compartment syndrome. I went to the doctor and they sent me to physical therapy for knots/scar tissue rehab and it went away but recently showed up again and the only thing I changed was starting taking xgels. These problems are extremely painful and will take you to your knees while you're running. Is the xgels possibly the problem? Thanks