Originally it was thought that the iron content of spinach made it a power-food. The secret we are finding now is that it’s not the iron, it’s the nitrates which are so effective in this vegetable. Nitric Oxide is an important molecule which opens up blood vessels, lowers blood pressure, and improves circulation. (Many Doctors prescibe nitrates for people that have heart problems, angina, ischemia etc.) So in effect, eating spinach makes your mitochondria (the little engine rooms of every cell) more effecient , thus producing quality energy boosts for your muscles.
Green leafy vegetables of all kinds are rich in nitrates. Pop open a can of your favorite; or better yet, eat’ em fresh and enjoy the natural boost of energy unlike anything coffee or redbull can give you!
Source: The Telegraph