I am a diabetic, whom are prone to this problem. My podiatrist told me to freeze a two liter bottle of water and place my toes on the bottle and roll the bottle forward and backward, forcing your foot to follow the curvature of the bottle. Doing this morning and night worked wonders. More often initially and for a least five minutes. Wear socks to avoid damage to skin. Good shoes with arch support are imperative. Best of luck.