For fueling exercise, we need macronutrients, protein, carbohydrates, and fats. Protein is the dietary component that helps your muscles repair after a workout while carbohydrates and fat are a major fuel source during exercise. Fuel is one thing, but don’t underestimate the importance that micronutrients play in health and athletic performance. Micronutrients are key players that play a support role for the macronutrients. Plus, exercise places stress on your body and there’s some evidence that this stress increases the need for some vitamins and minerals. Let’s take a closer look at the role micronutrients play in performance and which are of the most concern to an athlete or anyone who trains on a regular basis.
The Role of Micronutrients in Athletic Performance
Why do you need micronutrients anyway? Vitamins and minerals activate enzymes involved in metabolism and energy production, immune function, cellular repair, bone health, and more. There’s also some evidence that certain vitamins and minerals are impacted more by exercise than others. Not only is the requirement for some micronutrients potentially higher, but you lose water-soluble vitamins and minerals when you sweat and urinate, especially when you work out in a hot environment. Which micronutrients, if any, do you need more of when you exercise?
A challenging bout of exercise places oxidative stress on your body. Yet, the stress exercise places on your body lead to cellular adaptations that make your cells better at combatting oxidative stress in the future. So, it’s a health-promoting type of stress. The stress of exercise essentially upregulates your body’s own antioxidant defense system. Some of the key players that fight oxidative stress are vitamin C, vitamin E, beta-carotene, and selenium. If you do intense workouts regularly, the demand for these micronutrients may be higher. Vitamin E is the antioxidant vitamin most active in protecting cell membranes from damage and there’s some evidence that vitamin E requirements may be greater in athletes.
The best way to get these micronutrients is to eat a balanced, whole food diet. Fruits and vegetables, preferably raw, are the best source of vitamin C. You also find beta-carotene in fruits and vegetables, especially red and orange produce, although your body is best able to utilize carotenoids, like beta-carotene, if the vegetable is cooked. Selenium levels in the soil have been declining over the past 50 years, making it harder to get enough of this mineral you need in trace amounts for combatting oxidative stress. One of the best sources is Brazil nuts and you only need one or two per day to meet your body’s requirement for selenium.
As you can see, you can get antioxidants from foods like fruits, vegetables, whole grains, and nuts. Avoid taking antioxidant supplements, especially before a workout. If you have high levels of antioxidants in your blood stream before or immediately after a workout, based on some studies, it can interfere with the beneficial adaptations to exercise and you could miss out on some of the benefits.
B vitamins, of which there are eight, are involved in energy metabolism and tissue repair. In addition, folate and vitamin B12 support the production of healthy red blood cells. That’s important since red blood cells carry oxygen to your tissues during exercise. As you know, oxygen requirements skyrocket during an intense workout. A severe deficiency of folate or vitamin B12 would reduce your endurance.
But, do you need more if you’re not deficient? Studies look at whether you need more B-vitamins if you exercise are limited, but a 2000 study published in the Journal of Clinical Nutrition found that the requirement for thiamine, riboflavin, and vitamin B6 is higher in people who exercise regularly, although you can get enough by simply eating a varied, whole food diet. Where deficiency becomes more of a problem is if you restrict calories or eat a junk food diet. If you eat a vegan diet, you should definitely supplement with vitamin B12 since you only find this vitamin in fish, poultry, meat, and dairy.
Of note, is a study published in the International Journal of Sports, Nutrition, and Exercise Metabolism showing that individuals who are low in B vitamins don’t perform as well during high-intensity exercise and don’t repair and recover as well after a workout. If you do high-intensity exercise, make sure you’re eating foods rich in each of the B vitamins.
Vitamin D is of concern because so many people, including athletes, have less than optimal levels of the “sunshine vitamin.” Vitamin D plays a key role in calcium absorption and in maintaining bone health. Yet, vitamin D also impacts the level of hormones and activity of the immune system, both of which are relevant to athletes. Although there’s no clear evidence that supplementing with vitamin D improves athletic performance, a deficiency of vitamin D can manifest as muscle weakness and fatigue and that’s not favorable no matter what type of training you do. In older people, vitamin D deficiency is linked with balance problems and decreased reaction time.
The best source of vitamin D is sunlight but getting enough sun exposure to optimize levels is sometimes challenging. That’s why it’s best to check your vitamin D level and see whether you need a supplement and how much.
You need adequate iron to form hemoglobin to carry oxygen to tissues. A deficiency of iron, leading to anemia, can greatly impact athletic performance, by reducing oxygen delivery to your muscles. With a severe deficiency, you may experience shortness of breath, extreme fatigue, or lightheadedness. If you engage in endurance exercise, your iron requirements are slightly higher than a sedentary person. Iron deficiency is more common in women before menopause since you lose iron with each menstrual period. Before taking iron as a supplement, check your level. Most women over the age of 50 and men do not need an iron supplement and too much iron can be harmful since your body has no way to eliminate the excess. Rather, it’s stored in tissues and organs, like the liver.
Other minerals that are of importance for athletes include calcium, magnesium, and zinc. Calcium and magnesium both play a role in bone health. Calcium deficiency is also linked with a higher risk of bone fractures. Calcium deficiency is more common in vegans who don’t consume any dairy foods, although you can get enough calcium by consuming calcium-enriched non-dairy foods and calcium-rich, plant foods, like green, leafy vegetables.
The Bottom Line
Optimal nutrition is absolutely essential for exercise performance and recovery – and that includes micronutrients. That’s why it’s important to eat a balanced diet of whole foods and not restrict calories to the point that you compromise your body’s ability to perform.
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