I have been running for about 8 months now, and for some reason i cant up my miles per outing. My calves are too fatigued after about two miles. My calf muscles have toned up considerabley, and Ive lost about 40 pounds but I cant up the miles. I am trying to lose about 15 more pounds but have stopped loosing weight so I think i need to run more. I should mention Im flat footed, could this be the problem.My breathing is good, and I can run 2 miles faster, just cant run more.