When it comes to mineral supplements, magnesium gets a lot of buzz. This essential mineral is often touted as offering benefits for sleep quality, workout performance, and much more—but is all the talk true?

Magnesium is an essential dietary mineral and one of the most prevalent minerals in the body that help us maintain homeostasis. In fact, magnesium is a cofactor for over 600 enzymes.

Our bodies need magnesium when working out and exercising. It plays important roles in protein synthesis, energy production, carbohydrate metabolism, and nervous system health, so it’s no surprise magnesium is often recommended for boosting athletic performance. 

In this article, we’ll discuss the potential benefits of magnesium for exercise and whether supplementing magnesium makes sense for your lifestyle, health, and training goals.

What Does Magnesium Do?

Magnesium plays so many important roles in the body, we’d be hard-pressed to describe them all in one article. As stated above, magnesium is a cofactor for over 600 enzymes, which means magnesium is involved in countless body functions.1 

Most notably, magnesium plays a large role in energy metabolism, antioxidant level maintenance, immune function, RNA and DNA synthesis, protein synthesis, and normal cellular functions that we need for daily life.1 In essence, our bodies cannot function optimally without an adequate level of magnesium.

For those of us who are physically active, magnesium’s roles in protein synthesis, muscle function, energy metabolism, stress mitigation, and nervous system health are particularly interesting. 

Can Magnesium Impact Exercise Performance? 

Magnesium is often recommended for enhanced physical fitness. While it is essential to many bodily processes, research on whether magnesium supplementation benefits athletic performance is fairly limited. Let’s take a look at what some recent studies say so you can decide if supplementation may be right for you.

Improved Endurance Exercise Performance 

One older study looked at the effect of magnesium supplementation on measures of endurance-focused physical stress in competitive triathletes.2 Participants took magnesium orotate or a placebo for four weeks leading up to an endurance event. 

Researchers collected blood samples before and after the physical test and between each event. They evaluated the athletes’ energy and hormone metabolism as measured by glucose concentration, insulin levels, and venous oxygen partial pressure, as well as swimming, cycling, and running times.  

Participants who supplemented with magnesium had altered glucose utilization, reduced stress response, and improved athletic performance compared to those in the placebo group. 

This suggests supplementing with magnesium may help the body be more resilient to physical stress and could lead to stronger performance in endurance exercise. 

Preserve Muscle Mass and Power

Another large study of women between 18 to 79 years of age found that higher dietary intake of magnesium was associated with less age-related muscle loss and greater leg explosive power.3 This suggests getting enough magnesium may help you maintain muscle mass and power as you age. 

Aerobic Exercise, Muscle Strength, and Speed 

A 2017 review of studies looked at the impact of magnesium supplementation on exercise performance.4 It concluded that magnesium supplementation may improve aspects of both aerobic and anaerobic exercise, including decreased accumulation of lactate, increased muscle strength, and improved walking speed in older adults.

However, studies on magnesium for exercise performance are limited and results are mixed. Also, while magnesium may improve performance in those who have insufficient levels of magnesium in their bodies, it’s unclear whether it will help those who do get enough magnesium. 

Consider Supplementing Magnesium

More well-designed studies are needed to know for sure whether magnesium can improve exercise performance in people with insufficient and sufficient levels of magnesium. However, if you are highly active, experience high levels of physical or mental stress, or aren’t getting enough magnesium in your diet, it may be a good idea to supplement with magnesium.

How Can I Tell if I’m Magnesium Deficient?

Knowing whether you’re deficient in magnesium can be challenging because most magnesium in your body is stored within your cells and bones. While symptomatic magnesium deficiency is rare, almost half of Americans do not consume adequate magnesium from food.5 People with type 2 diabetes, gastrointestinal diseases, celiac disease, and alcohol dependence, as well as older adults, are at higher risk for magnesium deficiency. 

Some of the symptoms of magnesium deficiency can mimic our bodies’ reactions to stress, including fatigue, poor sleep quality, and dampened workout performance. Other symptoms of magnesium deficiency include:

  • Loss of appetite
  • Nausea
  • Vomiting
  • Fatigue
  • Weakness
  • Numbness
  • Tingling
  • Muscle contractions and cramps
  • Personality changes
  • Seizures
  • Abnormal heart rhythms

If you’re an active individual who may not be consuming adequate magnesium through the foods you eat or you are at higher risk due to your health condition or lifestyle, you may need a magnesium supplement. However, if you are healthy and consume adequate magnesium, taking a supplement may not offer any additional benefit for you.4

Foods High in Magnesium

If you’re wondering whether you’re getting enough magnesium from the foods you eat, check out some popular foods that are high in magnesium: 

  • Legumes (Black Beans): 1 cup cooked = 120mg of magnesium (28% of the daily value)
  • Nuts and Seeds (Almonds): 1 ounce = 80mg of magnesium (19% of the daily value)
  • Whole Grains (Quinoa): 1 cup cooked = 118mg of magnesium (28% of the daily value)
  • Leafy Greens (Spinach, cooked): ½ cup boiled = 78mg of magnesium (19% of the daily value)
  • Chocolate (Dark Chocolate 70-85% cacao): 1 ounce = 64 mg of magnesium (15% of the daily value)
  • Low-Fat Dairy Products (yogurt, plain): 8 ounces = 42mg of magnesium (10% of the daily value)

These examples give you an idea of the magnesium contents of different categories of foods. If you’re not a fan of black beans, you can substitute another legume, like lentils. While the exact amount of magnesium will vary, you’ll still be increasing your magnesium intake. 

For a better grasp of how much magnesium you consume on an average day, consider using a nutrition tracking tool. If you notice your intake is on the lower end, a magnesium supplement may be a good option for you. 

How Much Magnesium Is Enough?

The recommended dietary allowance for magnesium is between 310 to 420 milligrams for adults.5 Since many of us do not consume adequate magnesium through the foods we eat, many of us may benefit from supplementing between 250 to 450 milligrams of magnesium daily. 

However, while supplementing with magnesium is safe, taking too much can result in digestive discomfort, including diarrhea, nausea, and abdominal cramping. 350 milligrams may be the sweet spot for magnesium supplementation without the side effects. 

It’s worth noting that not all magnesium supplements are created equal. Magnesium oxide is among the types most likely to cause side effects and is not well-absorbed by the body. Magnesium citrate or magnesium lactate have higher absorption rates and are less likely to cause side effects. 


Magnesium may be an important supplement for active individuals looking to optimize their nutritional intake. Since magnesium plays an integral role in so many bodily processes—especially those related to exercise—it’s important to ensure you’re getting enough daily.

Supplementing with magnesium is generally safe—your body will use what it needs and your kidneys will eliminate any excess. However, taking too much can result in digestive discomfort. 

If you plan to supplement magnesium, choose a type that is well-absorbed and unlikely to cause side effects, like magnesium citrate or lactate. Always consult your physician, registered dietitian, or other qualified healthcare professional before starting a new supplement to be sure it is right for you and your health needs. 


  1. Razzaque, M. (2018). Magnesium: Are We Consuming Enough?. Nutrients, 10(12), 1863.
  2. Golf SW, Bender S, Grüttner J. On the significance of magnesium in extreme physical stress. Cardiovasc Drugs Ther. 1998;12 Suppl 2:197-202. doi:10.1023/a:1007708918683
  3. Welch AA, Kelaiditi E, Jennings A, Steves CJ, Spector TD, MacGregor A. Dietary Magnesium Is Positively Associated With Skeletal Muscle Power and Indices of Muscle Mass and May Attenuate the Association Between Circulating C-Reactive Protein and Muscle Mass in Women. J Bone Miner Res. 2016;31(2):317-325. doi:10.1002/jbmr.2692
  4. Wang, R., Chen, C., Liu, W., Zhou, T., Xun, P., He, K., & Chen, P. (2017). The effect of magnesium supplementation on muscle fitness: a meta-analysis and systematic review. Magnesium Research, 30(4), 120-132.
  5. Magnesium - Health Professional Fact Sheet. Accessed May 10, 2022. https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/