I switched from regular shoes to these minimal shoes because I wanted to train my calves more to make them effective. The first 3 weeks were brutal, with stiffness, cramps and direct pain in the calf muscles from only about 4 miles a day. received Dr. Schools use insoles (maybe a bit of cheating) and cut them to size. Now I don't even notice I'm wearing shoes. bypassed the first lace holes to properly tie more laces. very breathable, absolutely not waterproof, also avoid wet grass or allow wet feet.