So now that I seem to have found a way to get the SIJ back in place and relatively free of pain, how can I prevent it from slipping out in the first place? I assume that it involves some strengthening exercises? My MT thought I needed to strengthen the gluteus medius and both MT and PT said I should do the clamshell to strengthen as well. Is there any other exercises I should do to help? Is there anything I should avoid when I'm running or riding?