Magnesium has long lived in the shadow of calcium. Yet the importance of magnesium can’t be overstated. You need magnesium as a co-factor to keep your body running. In fact, it’s involved in over 300 chemical reactions inside your body. These include reactions that control nervous system function, muscle contraction, blood sugar control, protein synthesis, and energy production. Plus, it’s becoming increasingly apparent that magnesium is vital for a healthy heart, strong bones, and for blood glucose control. Whew! That’s a long list of responsibilities that magnesium has.
We know you need a certain amount of dietary magnesium to sustain life, but why might more be better if you work out? If you look at the many roles magnesium plays, especially in muscle contraction and energy production, it’s not a stretch to say that low levels of magnesium could impact exercise performance. More than half of the magnesium in your body resides in your bones, hence, it’s important for bone health. About 1% is in your bloodstream and the remainder lies in the tissues of your body.
Magnesium and Energy Production
As you know, exercise greatly increases the energy demands on your body. To meet your body’s energy needs, tiny “factories” inside your cells called mitochondria produce ATP. Without ATP, no muscle contractions could take place. Here’s the kicker – without magnesium, your mitochondria couldn’t even make ATP! So, without magnesium, you can’t contact your muscles.
One of the adaptations your body makes to endurance exercise is the production of new mitochondria. By making more mitochondria, in response to aerobic training, your muscles gain more ATP. Makes sense, doesn’t it? More ATP factories mean more ATP. Magnesium is a requirement for your cells to make new mitochondria. You also need magnesium to repair damaged mitochondria. Now you can see why magnesium is an essential mineral.
In addition, some research suggests that magnesium reduces oxidative stress related to exercise and helps with recovery from a tough workout. Magnesium may aid in exercise recovery in another way. Because of its impact on the central nervous system, it helps with sleep. So compelling are magnesium’s benefits for sleep and stress relief, that it’s sometimes called the “relaxation mineral.” It’s not surprising since magnesium can change the electrical activity in your brain.
Why You Might Need More Dietary Magnesium than You’re Getting
Now that we know that magnesium plays an integral role in fueling exercise, why might you need more of it? For one, there are concerns that even sedentary people don’t enough of this mineral. The reason you need more magnesium if you exercise is that you lose magnesium through urine and when you sweat. According to one scientific article, strenuous exercise increases magnesium requirements by 10 to 20%. When you consider that even sedentary people don’t get enough magnesium, it’s not hard to see how active people could have a magnesium deficit.
Strength, Power, Endurance, and Magnesium
What does research show? In a study published in the Medicine and Science in Sports and Exercise, researchers tested electrolyte levels, including magnesium, in men who had just completed a marathon. Potassium was the mineral most depleted by the race but magnesium came in a close second. The runners also showed abnormal heart rhythm activity on electrocardiogram after the race. Low magnesium may be the culprit here too since it helps regulate the rhythm of your heart.
In another study focusing on power athletes, researchers found a correlation between dietary magnesium intake and vertical jump height. In fact, athletes who supplemented with 350 milligrams of magnesium for a month improved their jump height by an average of 3 centimeters. Still another study showed a relationship between body magnesium stores and measures of strength and jumping.
What’s less clear is whether getting more magnesium through diet or supplements improves exercise performance if you aren’t deficient or marginally deficient in magnesium.
Best Sources of Magnesium
Fortunately, you find magnesium in a variety of healthy foods. When you’re most likely to develop a deficiency is if you restrict calories too much through dieting. There’s also evidence that aging, illness, stress, and alcohol lower your body’s magnesium stores. In addition, some medications, especially diuretics, heart medications, and chemotherapy drugs can deplete your body of magnesium.
If you eat a processed food diet, you’re at risk of magnesium deficiency. Processing removes many of the nutrients from food and, in the case of magnesium, it’s not added back in. So, your best bet for giving your body the magnesium it needs is to eat whole foods with dietary magnesium. Both plant and animal foods can be good sources of magnesium. Some of the best are green, leafy vegetables, legumes, nuts, seeds, and soy-based foods.
One potential problem with getting most of your magnesium from whole grains and legumes is these foods contain compounds called phytates. Phytates have the ability to bind to magnesium so that your body can’t absorb it as efficiently. That’s why you need magnesium in your diet from a variety of sources.
The Bottom Line
Magnesium deficiency is believed to be fairly common, affecting up to half of all people. Magnesium plays a number of vital roles in your body as discussed above. Plus, you lose it when you sweat and through urine loss as well as when you eat a calorie-restricted diet. In terms of exercise performance, low levels of magnesium may affect strength and power capabilities as well as interfere with recovery from exercise.
So why not add more magnesium to your diet? What you want to avoid, to preserve your tissue levels of magnesium, is processed food and empty calories. When you work out, your nutritional requirements are higher in many regards, so make sure you’re choosing nutrient-dense foods and consuming enough of them, including ones rich in magnesium.
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