Eat Your Way to Health and Happiness
Peas, beans, and peanuts are stand-up sources of magnesium, a mineral that plays a core role in your body's energy production. (It's involved in more than 300 biochemical reactions in your system.) "When you exercise, magnesium is redistributed throughout the body to help energy molecules get to where they're needed," explains Forrest H. Nielsen, PhD, a research nutritionist in the USDA's Agricultural Research Service.
A deficiency may cause you to fizzle out more easily. Workout queens need to be extra vigilant (you lose some magnesium through sweat). Legumes will help you fulfill the RDA of 320 milligrams: One cup of white beans has 134 milligrams; even a cup of frozen peas delivers 35 milligrams.