I'd be curious about a clarification myself.
I can see where taking the supplement with weight training might have benefit, though a number of studies say otherwise.
Nobel Prize
"Discovering how NO works in our bodies is an exciting, important chapter in the history of cardiovascular medicine. In 1998, the Nobel Prize was awarded to three Americans for their independent discoveries concerning NO as a signaling molecule in the cardiovascular system, one that produces another substance known as a second messenger. Second messengers help in some way to carry a message from the outside of the cell to the inside.
Faulty Extrapolation?
Supplement manufacturers and many bodybuilders have taken that fact to a theoretical level unsupported by medical research. The theory is that supplementation creates and sustains levels of NO in the skeletal muscles—levels that are assumed to enhance oxygen delivery, glucose uptake, muscle velocity, and muscle growth."
All I can say is, I've had good results with the stuff I've been using with weights.
But taking this supplement with cardio is an entirely different ballgame and not recommended. Someone explains why on Yahoo Answers:
"You should not take NO Xplode before a cardio workout. Here is why...NO Xplode was engineered for the purpose of increasing muscular vascularity while you work out anaerobically. In a nutshell, this means that it opens up the blood vessels to increase blood flow to the muscles being worked while lifting weights. The more blood that stays in the muscle being worked, the more endurance that muscle will have. NO Xplode was engineered to create a maximum workout experience when hitting the weights.
That being said, by increasing your muscular vascularity, the blood tends to stay in the muscle. This is good for weight workouts but terrible for aerobic workouts. Aerobic workouts cause your heart rate to increase. Your heart rate increases because your body needs more oxygen to function at a higher stress level. Your heart beats faster to carry more oxygen to the rest of your body. If NO Xplode is in the system, the blood will want to stay in the muscles rather than improve overall circulation. When on NO Xplode, the heart speeds up but pumps less blood. The result can be hypotension or low blood pressure. This can result in blurred vision, fatigue, dizziness, confusion, and loss of consciousness (fainting)."
That makes a lot of sense to me.