I am 23, 6'0", 180 lbs., have no health problems, no heart problems, and am extremely physically active. I was considering taking supplements for lifting weights and cardio exercising, but I don't like all of the caffeine and other stimulants that are in most workout supplements along with the high caloric content of most. My friend in grad school recommended that I try vasodilators to increase the blood flow to my muscles. Is there anything I should be concerned about if I took these for working out? And is there a certain type of vasodilator that would be better suited for this than others?