Recently I had beem getting numb toes when I ran. I went to the Running Room where I buy my runners they mentionned the metatarsal in the ball of my foot and to put this gel in my shoe. When this didn't work I visited a foot specialist and he found that I had Morton's Neuroma and fitted me with orthotics and ta da no more problemo
... I get tingling in my upper thighs/butt area when I have had a very good run also some soreness in the hips, but I just chalked it up to a good butt and leg blasting workout,
plus it goes away after a few minutes of cool down, so I'm not too worried about it...