Ask a handful of athletes about supplements; they’ll probably wax poetic over caffeine and protein powder. Perhaps some will even acknowledge the benefits of creatine and fish oil. Alternatively, bring up the benefits of magnesium, and all you hear is crickets.
Magnesium is a dietary mineral often neglected in the standard American diet. According to Examine.com, “Magnesium deficiencies are common in developed countries and are often caused by diabetes and other conditions. A lack of magnesium will raise blood pressure and reduce insulin sensitivity.” For the modern athlete–and the general population-meeting a standard daily dose of 200-400 mg is a considerable barrier.
Magnesium is essential to over 300 biological reactions in the human body. Relevant to athletic performance include muscular contraction and relaxation, cardiac function, and bone metabolism. Magnesium further supports the metabolism of adenosine triphosphate (ATP). ATP is the ‘energy’ that fuels both cardio and weight training.
Magnesium deficiencies in athletes may go largely unreported. They are at a significantly higher deficiency risk due to sweat loss during physical training. Symptoms include increased blood pressure and neural excitation yet are frequently misconstrued as stress.
Magnesium Deficiency Symptoms
- Leg Cramps
- Digestive Problems
- Low Mood
One way to discern the two involves your nutritional practices. The grain-rich, western diet is remarkably devoid of magnesium. By comparison, prominent sources like nuts and leafy greens have less consumption. When interpreting your eating habits refer to the fact sheet below to see where you stack up.
What Does the Evidence Say?
Despite the claims of well-intentioned practitioners, magnesium isn’t some magic mineral that will springboard your athletic performance. However, there are real benefits to supplementation for those attenuating a deficiency.
Let’s look at the evidence to guide us through a few performance markers.
Blood Pressure – Magnesium has exhibited a notable effect in reducing blood pressure. If a subject meets one of two criteria, either the individual has low magnesium levels in the body or elevated blood pressure (140/90 or above).
Aerobic Exercise – One study that assessed aerobic exercise capacity noted a significant improvement during extreme physical stress. In this case, triathletes were the subjects. Albeit notable, it needs to replicate with more studies.
Muscle Oxygenation – The same study on aerobic capacity also accounted for muscle oxygenation levels. Healthy athletes showed a noteworthy improvement in oxygenation levels when supplementing with 17mmol of Magnesium Orotate daily for four weeks.
Mood – Magnesium affects the body hormonally. Low levels are associated with low testosterone, and low testosterone is associated with low mood. Also, early evidence suggests that magnesium modulates the activity of NMDA receptors in the nerves, which causes excitement and stimulation. Low magnesium delivers a more passive stimulation to the NMDA receptors, thus, leading to symptoms of anxiety.
Strength – Testosterone is the best-known androgen (male hormone). Athletes low in magnesium may also be at risk for low testosterone. Specifically, low testosterone can reduce libido and cause fat gain, muscle loss, and bone loss. Chronically low levels will be detrimental to performance improvements.
Magnesium Rich Foods
The most common and abundant sources of magnesium come from leafy green vegetables, nuts, legumes, and animal tissue. Typically 30-40% of the dietary magnesium consumed is absorbed by the body. Check out this magnesium fact sheet which presents the amplest food sources to include in your diet.
- Dark Leafy Greens (e.g., Spinach, Kale)
- Nuts/Seeds (e.g., pumpkin seeds, almonds, cashews)
- Beans (e.g., black, kidney)
- Chicken Breast
The standard dose for magnesium supplementation is 200-400mg. Any form of magnesium can help assess a deficiency except for Magnesium L-threonate since it contains less elemental magnesium per dosage. Magnesium chloride and magnesium oxide are associated with cases of bloating and diarrhea due to lower absorption rates. Therefore I suggest supplementing with Magnesium citrate. Magnesium should be taken daily, with food.
Magnesium is the second most prevalent electrolyte in the human body. It assists in regular performance variables like muscle contraction, cardiac output, bone metabolism, and energy production. Athletes are at a higher deficiency risk because of the physical demands of exercise (e.g., sweat loss). Improving magnesium consumption starts and stops with nutrition. If you’re a parent, serve your kids a variety of foods to meet their needs. If you’re a coach, educate your athletes and refer them to a sports dietitian or nutritionist. They may not listen to you, but it’s your responsibility to deliver the necessary information for them to make an informed decision about their health.