 1 Prostate specific antigen 2.5 49yr of age or 3.5 age 50yr of age, 2 baseline hematocrit greater than the upper limit of normal for the laboratory used, 3 EKG with ischemic changes, 4 history of myocardial infarction, unstable angina, stroke, transient ischemic attack, or deep vein thrombosis, 5 history of prostate or breast cancer, 6 screening T level 500ngdL, 7 diabetes requiring treatment, 8 current drugalcohol abuse, 9 disease other than MS causing fatigue, such as obstructive sleep apnea or other sleep disorder, or untreated thyroid dysfunction, 10 RRMS, 11 Beck Depression Inventory-II BDI score over 20, 12 cognitive dysfunction such that subject cannot perform study tests, 13 inability to undergo MRI, 14 current or expected use of amphetamines, or 15 anticipated changes in medical treatments that might affect fatigue scores e.g., expected changes in spasticity, sleep, or depression medications. 