Vitamin supplements have gotten some bad press lately, as more studies find that mega-doses of these healthy chemicals may actually do more harm than good. But that doesn't mean you should let your nutrient intake slide. Studies also show that very active people may need higher levels of key energy-producing and muscle-mending nutrients.
"The more you ride the more you eat, so you'll naturally get more vitamins and minerals than someone who eats less," says Leslie Bonci, MPH, RD, CSSD, RDN, owner of Active Eating Advice and co-author Bike Your Butt Off. "But your food choices are key, because some of the ones you need most can be hard to get through diet alone."
Vitamin D: The Sunshine Vitamin"More people have less-than-adequate levels of vitamin D," says Bonci. "And it's virtually impossible to get enough just through food." That's because so few foods found in nature are rich in D. Fatty fish like salmon, tuna, and mackerel are good sources of vitamin D; cheese and egg yolks are okay; and you can get a healthy dose in fortified milk. But for most of us, it doesn't add up to enough.
As the nutrient's nickname implies, you also make vitamin D from exposure to sunlight, but even outdoorsy cyclists can be deficient since most of us spend the majority of our waking hours inside, andslather ourselves with sunblock when we step out. Vitamin D is a key player in building bones, making and maintaining muscle, and revving metabolism. Research shows that increasing vitamin D levels in your blood to 75 to 100 nmol/L can boost your aerobic capacity, muscle growth, muscle force, and power, and shorten your recovery time from hard bouts of exercise, as well as improve bone density. That said, too much (more than 125 nmol/L) can produce negative side effects. Stay on the safe side by supplementing with doses ranging between 1000 and 5000 IU of vitamin D3 (the most effective type for increasing vitamin D plasma levels) per day.
Vitamin C: The Immunity BoosterOnly about 10 to 20 percent of adults get their recommended 9servings of fruits and veggies every day. "That's where the C is," says Bonci. You need vitamin C to keep your immune system strong, fight cardiovascular disease, keep your eyes healthy, and even prevent wrinkles (we cyclists do have our faces in the sun and wind a lot, after all). "Vitamin C is also a bit fragile and levels of the nutrient diminish when cut surfaces are exposed to the air, or when juice is exposed to light," she says. Citrus fruits, tomatoes, strawberries, pineapple, peppers, kale, cantaloupe, broccoli, cauliflower, and red cabbage are rich in C. Eat plenty of those and you're good to go. If you slack in the produce department, you can safely take vitamin C supplements. You don't need mega-doses—500mg a day is plenty.
Vitamin E: The Better BreatherThis antioxidant vitamin protects your cells—especially those in your muscles and lungs, which take a beating during intense cycling efforts—and appears to improve lung health as well as breathing capacity at altitude. If you eat a very low-fat diet (which you shouldn't for many reasons), you could be skimping on this essential nutrient, as it's found mainly in oils like olive oil and nuts. This one is best to get through foods since recent research shows nutritional supplements don't appear to offer the same protection—and in fact may be harmful. Instead eat a handful or two of almonds every day, as just one ounce (about 25 nuts) delivers more than a third of your daily requirement. Drizzle olive oil on your vegetables, salads, and grain dishes and eat nuts, eggs, leafy greens like spinach, and fortified cereals to get the rest. Go easy on corn, canola, and soybean oil, however. Interestingly, a study in Respiratory Research found that while one form of Vitamin E—alpha tocopherol, the kind in olive and sunflower oil—is helpful for lung health, its counterpart (gamma tocopherol, which is found in the three oil varieties mentioned) actually seems to reduce lung function overtime. Adults need about 15mg per day.
Magnesium: The Food ConverterYour body uses this essential mineral to maintain healthy blood pressure, bone development, blood sugar, and even muscle and nerve function. It also plays a key role in processing carbs and fats for fuel. Magnesium is found across the food chain in a variety of plant and animal foods: green leafy vegetables, legumes, nuts, seeds, and whole grains; fish, poultry and beef; and even our favorite, chocolate. It's easy to get through your diet, but unfortunately, it's also easy to lose.
When you ride hard, you pee and sweat out enough magnesium to increase your requirements by up to 20 percent. That means if you don't routinely get the daily recommended 320mg of magnesium (for women) or 420mg (for men), you could easily be deficient. You don't want to let that happen: Research shows that maintaining healthy magnesium levels is especially important for maintaining muscle and bone and preventing loss of both as we age. Eat a diet rich in whole foods and, if you're very active, consider taking a 400mg magnesium supplement to keep your levels in the optimum zone.
Iron: The Oxygenator
Iron is the mineral workhorse your body uses to build the red blood cells that carry fresh oxygen to your muscles via your bloodstream. Run low, and you risk developing iron-deficiency anemia, which can leave you chronically tired and hamper your riding. Women are more likely to become deficient than men because of menstruation. Very active people are, too, because we lose iron through sweat and red blood cell breakdown. Iron is easy to get through food, especially if you eat meat, poultry, or seafood, because they are all good sources of heme iron, which is easier for the body to absorb than non-heme plant sources. To maximize the amount of iron your body absorbs, eat iron-rich foods with vitamin C-rich foods, such as citrus, peppers, leafy greens, and tomatoes. Vitamin C helps increase the absorption of iron from plant foods—particularly important if you're a vegan cyclist. "Even red meat-eaters may be deficient in iron, however," says Bonci, "which can definitely impact cycling." An iron supplement can help you optimize your daily intake—and performance. A meta-analysis of iron supplements and female exercisers found that women athletes (particularly those low in iron) who took iron supplements were able to improve their maximum power as well as their exercise efficiency, meaning they put out more power at lower heart rates. Women ages 19 to 50 need at least 18mg of iron a day. Older women and men need 8mg daily. You can definitely get too much iron, though, and that's not good for your heart—so stick to natural food sources unless you suspect you're low. Then get your levels checked by your doc before supplementing.
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