Better workouts may be as simple as a supplement. According to the Journal of Nutrition, women taking iron are able to exert less energy and maintain a lower heart rate while exercising.
If you're iron-deficient, increased intake of the mineral could help drastically. But, keep in mind that too much can put you at a greater risk for heart disease, diabetes, and even cancer. Still, it's clear we need to get the iron we need if we want to pump iron like a pro. So, spinach or supplement — what'll it be? Click through to find your best iron strategy. (Shape)