I sized based on my old adidas story but they cause a lot of pain in my feet when they flex at the toe joint. The upper part of my right leg always hurts when I wear them around town. I've tried to fix it by wearing thick wool socks and I may have to completely re-attach both shoes to avoid this pain in my feet. I've never had this problem with mid size black adidas with white soles. I hope that when I disassemble them, the flexibility in them will solve this problem.