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Are you getting enough vitamins and minerals to keep training hard?
Why You Need It: Calcium is essential to bone integrity, hormone secretion, proper nervous system function, muscle contraction, and blood vessel function.
When You’re Running Low: While regular exercise has been found to boost bone mineralization, consistently training hard can lead to a decrease in circulating levels of sex steroids (i.e., estrogen). Low levels of sex steroids can lead to an imbalance in calcium absorption. And when your blood calcium levels dip, the risk for low bone mineral density (i.e., osteopenia and osteoporosis) and stress fractures increases.
Top Up: Aim for 1,000–1,200 milligrams of calcium per day — half in the morning, half at night, to maximize absorption. Check the label for the amount of elemental calcium; the amount of elemental calcium is the figure you should use to calculate your true daily intake.
Best Food Sources: Collard greens, spinach, turnip greens, plain yogurt, sardines, salmon, and fortified orange juice.
Why You Need It: This vitamin plays a crucial role in bone mineralization through the regulation of calcium and phosphorus. It promotes the absorption of calcium, integrates calcium into bone tissue, and helps maintain bone density and strength. It also regulates immune and neuromuscular function.
When You’re Running Low: A deficiency in this vitamin can result in bone loss, muscle weakness, and compromised immune function.
Top Up: Aim for 400–800 IU per day.
Best Food Sources: Dairy products, fortified cereals, wild salmon, white fish, and mackerel.
Why You Need It: This tireless multitasker is involved in more than 300 biochemical reactions, including muscle contraction, nerve function, hormonal interactions, immune function, and bone health. It’s also vital for metabolizing carbohydrates, fats, and adenosine triphosphate (ATP), the energy system used during hard training.
When You’re Running Low: A shortfall in this mighty mineral can limit your body’s ability to generate energy, leading to fatigue, reduced strength, and muscle cramps. Because magnesium is also lost through sweat, training hard in hot and humid environments further leeches your body of this mighty mineral.
Top Up: 400–800 milligrams daily; look for one with magnesium citrate, which is more readily absorbed.
Best Food Sources: Swiss chard, spinach, bran cereal, black-eyed peas, pumpkin seeds, almonds, wild salmon, and halibut.
See AlsoThe Power of Magnesium
Why You Need It: This antioxidant not only fights damaging free radicals, it also has strong cortisol-lowering effects. Cortisol, a hormone produced by the adrenal glands, begins to spike toward the end of your workout.
When You’re Running Low: The daily jolts of cortisol spur the catabolism of proteins, resulting in poor recovery and the break down, or loss, of muscle tissue.
Top Up: 500–1,000 milligrams daily with food, preferably post-workout.
Best Food Sources: Brussels sprouts, bell peppers (red, yellow, and green), papaya, pineapple, citrus fruit, and fortified orange juice.
Why You Need It: This mineral is critical in growth, building, and repair of muscle tissue, energy production and immune status. It’s also essential for thyroid hormone and insulin function.
When You’re Running Low: Inadequate intake of this mineral can lead to impaired immune function. Your metabolic rate also slows, making it harder to burn off unwanted body fat.
Top Up: 30–50 milligrams daily, on an empty stomach.
Best Food Sources: Seafood, liver, beef, wheat germ, bran cereal, pumpkin seeds, and lentils.
Why You Need It: Potassium is an essential mineral and electrolyte that is promotes proper cell, nerve, brain, heart, kidney, and muscle function.
When You’re Running Low: The body, particularly the kidneys, tightly regulates blood levels of potassium. But when these levels take a nosedive, a condition known as hypokalemia, the result can be fatigue, decreased muscle strength, muscle cramps, mood changes, irregular heartbeat, and gastrointestinal disturbances, such as bloating and constipation.
Top Up: The adequate intake (AI) is 4,700 milligrams per day. Because over-supplementation can easily catapult you in the opposite direction and interfere with kidney function, try to get your potassium from food sources and maintaining proper hydration.
Best Food Sources: Bananas, avocados, sweet potatoes, white beans, soybeans, almonds, and prunes.