Magnesium and Athletes

Magnesium is the fourth most abundant mineral in your body. It is involved in over 600 cellular reactions, ranging from DNA synthesis to supporting muscle contraction (1).
While it is estimated in the U.S. that up to 68% of American adults do not consume the recommended amount of magnesium (2), the National Nutrition Survey II (3,4) finds no significant magnesium deficiencies in the German population. The recommended daily allowance (RDA) for adults is 420 mg (men) and 320 mg (women), while the D-A-C-H guidelines recommend 350 mg (men) and 300 mg (women).

FUNCTIONS OF MAGNESIUM

Ensures a normal heartbeat

Magnesium is important for maintaining a healthy heartbeat. It naturally competes with calcium, which is essential for generating heart contractions. When calcium enters the heart muscle cells, it stimulates the muscle fibers to contract. Magnesium counteracts this effect and helps the cells relax (5,6).
When magnesium levels are low, calcium can overstimulate heart muscle cells. A common symptom of this is a rapid and/or irregular heartbeat (7). In addition, the sodium-potassium pump—an enzyme that generates electrical impulses—requires magnesium to function properly.

Muscle Contractions

Magnesium also plays a role in regulating muscle contractions. Just as in the heart, magnesium acts as a natural calcium blocker in skeletal muscle, helping to relax the muscles. 
In the muscles, calcium binds to specific proteins (troponin C and myosin). This process changes the shape of these proteins, thereby initiating a contraction (8). Magnesium competes with calcium for the same binding sites, thereby helping to relax the muscles. A magnesium deficiency can cause the muscles to contract too strongly. This results in cramps or spasms. For this reason, magnesium is often recommended for treating muscle cramps (9); however, studies provide only limited evidence that magnesium is effective for relieving cramps, which suggests that there must be other causes of muscle cramps (10).

Sleep

Magnesium has been shown to bind to gamma-aminobutyric acid (GABA) receptors. The neurotransmitter GABA helps calm nervous system activity and thus promotes restful sleep (11). Animal studies also show that magnesium can regulate the production of melatonin, a hormone that plays a key role in controlling the body’s sleep-wake cycle (12).
Given this, it is not surprising that taking magnesium can improve sleep quality by relaxing the mind and body. This relaxation helps people fall asleep faster and improves the quality of their sleep (13). In a study involving 46 older adults, those who took a daily magnesium supplement fell asleep more quickly. They also reported better sleep quality and fewer symptoms of insomnia (14).

Conclusion

Magnesium influences fundamental bodily functions that are particularly important for athletes.

Magnesium and Athletic Performance

Numerous studies have already examined the effects of magnesium supplementation in athletes:

• A study of women on a low-magnesium diet showed that, for a given workload in cycling, peak oxygen uptake, total and cumulative net oxygen utilization, and heart rate increased significantly during the period of magnesium restriction. The extent of the increase correlated directly with the degree of magnesium depletion; that is, magnesium deficiency reduced metabolic efficiency and increased the oxygen consumption and heart rate required for a given exercise load (15).
• A study conducted under submaximal exercise conditions showed that magnesium supplementation reduced heart rate, respiratory rate, oxygen uptake, and carbon dioxide production at a given workload (15).
• A study involving male athletes who consumed 390 mg of magnesium per day for 25 days resulted in increased peak oxygen uptake and total work output during exercise tests (16).
• A study of physically active students showed that supplementation with 8 mg of magnesium per kilogram of body weight per day led to a significant increase in endurance performance and a reduction in oxygen consumption during submaximal exercise (17).
• A study of untrained participants showed that magnesium supplementation positively influences torque, body weight, and lean body mass in conjunction with strength training (18).
• A review article demonstrating that athletic performance can be negatively affected by magnesium deficiency. It also shows that magnesium supplementation can improve performance parameters in both aerobic and anaerobic exercises (19).

Conclusion

A small selection of available studies examining the influence of magnesium on athletic performance highlights its importance for energy metabolism, cardiorespiratory function, and muscle activity.

Do Athletes Need More Magnesium?

There are two aspects to consider here:

1. During strenuous physical activity, magnesium loss through sweat and urine increases by 10 to 20 percent (20). It is therefore not surprising that magnesium deficiencies are regularly or seasonally observed in athletes across many sports (such as track and field, soccer, or swimming) (21–23).
2. Athletes who compete in weight classes or in sports with an aesthetic focus regularly consume diets that fall short of optimal energy and, consequently, nutritional requirements. They are therefore particularly susceptible to insufficient magnesium intake. Studies of athletes show that the prevalence of suboptimal magnesium levels is significantly higher than that observed in the general population. Vitamin D status is also a topic of discussion in this context (24).

Summary

As a mineral, magnesium performs essential functions for health, performance, and recovery. This central role makes it a key factor for athletes. Studies show that magnesium deficiency is directly linked to a decline in performance. For this reason, athletes should make it a priority to ensure an adequate magnesium intake. It can be assumed that the actual requirement for athletes is somewhat higher than the RDA or D-A-C-H guidelines specified for the general population.

Best regards,

TEAM Peak Performance Products

Sources
(1) https://pubmed.ncbi.nlm.nih.gov/25540137/
(2) https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/
(3) https://www.dge.de/wissenschaft/referenzwerte/magnesium/
(4) https://www.mri.bund.de/fileadmin/MRI/Institute/EV/NVSII_Abschlussbericht_Teil_2.pdf
(5) https://pubmed.ncbi.nlm.nih.gov/26069819/
(6) https://pubmed.ncbi.nlm.nih.gov/6375330/
(7) https://pubmed.ncbi.nlm.nih.gov/22087052/
(8) https://pubmed.ncbi.nlm.nih.gov/7286246/
(9) https://pubmed.ncbi.nlm.nih.gov/8754704/
(10) https://pubmed.ncbi.nlm.nih.gov/22972143/
(11) https://pubmed.ncbi.nlm.nih.gov/18799816/
(12) https://pubmed.ncbi.nlm.nih.gov/22826693/
(13) https://pubmed.ncbi.nlm.nih.gov/27933574/
(14) https://pubmed.ncbi.nlm.nih.gov/23853635/
(15) https://pubmed.ncbi.nlm.nih.gov/12615252/
(16) https://pubmed.ncbi.nlm.nih.gov/10919964/
(17) https://pubmed.ncbi.nlm.nih.gov/17063625/
(18) https://www.tandfonline.com/doi/abs/10.1080/07315724.1992.10718233
(19) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5622706/
(20) https://www.jle.com/fr/revues/mrh/e-docs/update_on_the_relationship_between_magnesium_and_exercise_272229/article.phtml
(21) https://pubmed.ncbi.nlm.nih.gov/31829845/
(22) https://pubmed.ncbi.nlm.nih.gov/34533486/
(23) https://www.labmed.org.tw/upfiles/issues/20091221145836.pdf
(24) https://jom.osteopathic.org/abstract/role-of-magnesium-in-vitamin-d-activation-and-function/