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Sweat contains many minerals crucial for any runner’s fueling. All four of these may fall short of the optimal amounts in your daily diet.
WHY YOU NEED IT: This bone builder also plays a role in muscle contraction, muscle and liver glycogen formation and breakdown, and regulating nerve impulse transmission.
WHERE TO GET IT: Occurring naturally in milk, yogurt and cheese, calcium can also be found in fortified non-dairy milks and juices. Green leafy vegetables, such as kale, collards, dandelion greens, broccoli and bok choy, are other sources.
WHY YOU NEED IT: A component of more than 300 enzymes in the body, magnesium is involved in muscle contraction, helps with calcium absorption and has roles in blood-glucose control as well as blood-pressure regulation.
WHERE TO GET IT: Dark leafy greens are a solid source, as are pumpkins seeds, sunflower seeds, almonds, black beans, kidney beans, avocado, whole grains, halibut and chocolate.
WHY YOU NEED IT: It aids in the breakdown and use of carbohydrates and regulates heart function.
WHERE TO GET IT: Sweet potatoes, tomato sauce, beet greens, kidney beans, lentils, split peas, yogurt, milk, bananas, oranges, white potatoes, broccoli, carrots, dried apricots, ﬁsh and squash all are filled with the element.
WHY YOU NEED IT: The element Na enables normal body fluid balance and has a role in nerve impulse transmission and muscle contraction.
WHERE TO GET IT: Sodium found in natural foods is relatively low and contributes only 10 percent to the average American’s diet. Salt added to food and used in cooking contributes 10 to 15 percent. The vast majority comes from processed foods like canned soup, crackers, breads, sauces, pretzels and salad dressings.
Monique Ryan is a Chicago-based nutritionist and author of Sports Nutrition for Endurance Athletes, 3rd Edition.