Who remembers the cartoon character Popeye and his bulging bicep muscles? He knew that consuming enough spinach per day would help give him size and strength that many of us seek, but why is this? Spinach is high in nitrates which improves your endurance and strength during a workout. A small bag of spinach per day will give you enough nitrates for your body to use when you need it.
How does it work? Well nitrates allow your blood vessels to dilate so that more oxygen and blood flow can pass to the muscles. When this happens it allows your body to last longer during exercise and increases your overall performance. Add in some spinach with your meals to see this difference.