I have been having myoglobin in my urine since 9th grade after almost every run. I am 22 now. I haven't stopped running at all, I have had exploratory surgery to check kidnee function and I am doing fine but the doctor never told me what was causing my deteriorating muscle condition. I keep struggling with increasing my mileage and I get burnt out very easily. Long runs are my worst. It takes days to feel normal again, sometimes a week. I just found this disease and I was wondering if any other runners on here have been diagnosed with this gentic disorder that doesn't allow the body to break down glycogen. I am curious if you were able to improve your PR's and what exact symptons you had.