Heart failure causes a multitude of changes that reduce a persons endurance and ability to exercise enough to perform the tasks of daily living. It can also cause decreased sensitivity to insulin, which can result in insulin resistance or diabetes. Now researchers have discovered that women as well as men with heart failure function better with testosterone therapy. In the Italian study, reported in the Journal of the American College of Cardiology on October 12, 2010, women with stable heart failure were given a six-minute walking test, cardiopulmonary exercise test, tests that evaluated the strength and contractability of their quadriceps (thigh muscles), echocardiogram and blood test for insulin resistance. They were then given testosterone or placebo patches to wear for six months.