Magnesium and Its Role in Athletes' Diet

November 18, 2022

Minerals are essential elements, just like vitamins, and must form part of the athlete's daily diet in adequate quantities. They participate in a wide variety of processes, both in general metabolism (mechanism for obtaining energy, synthesis of a multitude of vital substances and structures, etc.) and in more specific functions (forming part of bone tissue, oxygen transport, muscle contraction, etc.) 

Minerals can be classified into macrominerals (calcium, phosphorus, and magnesium), microminerals or trace elements (iron, iodine, fluorine, chromium, copper, selenium, zinc, cobalt, manganese, and molybdenum), and electrolytes (sodium, potassium, and chlorine).

Magnesium is essential because it is involved in more than 300 different enzymatic reactions. It participates in the metabolism of food components, the transformation of complex nutrients into their elementary units, and the synthesis of numerous organic products. It is a basic mineral for athletes because of its role in muscle relaxation and the proper functioning of the heart.

Magnesium deficiency is rare, but when it occurs, it causes severe repercussions such as muscle cramps and pains, irregular heartbeat, reduction of blood pressure, and weakness.



  • Protein and energy metabolism 

  • Bone formation

  • Metabolic regulators

  • Nerve function

  • Muscle function


  • Growth failure

  • Behavioral disturbance (depression)

  • Weakness

  • Muscle spasms


  • Diarrhea

  • Nausea

  • Vomiting

  • Hypotension


  • Whole grains

  • Nuts

  • Green vegetables 

FOODS RICH IN MAGNESIUM Quantity of Mg (mg/100 g of food)  


  • Nuts 250

  • Snails 250

  • Whole grains 212

  • Legumes 150

  • Corn 120

  • Chocolate 100

  • Norway lobster 76

  • Chard 70

  • Pasta 58

  • Dates 58

  • Sardines 50

  • Gruyere cheese 47

  • Banana 40

  • Raisins 40

  • Chestnuts 36

  • Peas 35

  • Potato 27

  • Asparagus 22

  • Melon 18

Strenuous sports practice generates a loss of magnesium, and the lack of magnesium leads to a reduction in the capacity of resistance and adaptation to the effort. 

It is therefore essential to assess the availability of magnesium in the athlete's diet. This mineral is abundant in nuts, legumes, whole grains, and green vegetables (lettuce, endive, chard, spinach.) 

Meats, dairy products, and seafood are somewhat poorer sources. This mineral is also present in the composition of some natural mineral waters.

Magnesium (mg) is mainly found combined with calcium and phosphorus in the complex salts of bones (approximately 70%). 

The rest is distributed in plasma (1.4-2.5 mg/ml), mainly in red blood cells and muscle tissue, acting with calcium in muscle contraction. 

What is the role of magnesium in the different systems of the organism?

Magnesium plays a key role in the different systems of the organism. 

  • Cardiovascular system: magnesium at the cardiac level acts as a calcium-antagonist, decreasing conductivity, and irritability, in addition to presenting cardio protective, anti-hypoxic, and anti-ischemic properties. Magnesium deficiency may cause cardiomyopathy and vascular lesions.

  • Blood system: It acts on platelets (the smallest blood cells in our bodies) as a physiological antithrombotic, and its deficiency causes a reversible platelet hyper aggregation. Its membrane stabilizing action prevents red blood cell deformation, and therefore, its deficiency can cause structural alterations in their membrane. As for white blood cells, magnesium increases their proliferation and phagocytic capacity, enhancing the transformation into destructive cells and decreasing the vascular reaction, stabilizing platelets and red blood cells. 

  • Bone and cartilage system: Magnesium is a necessary element for bone growth and mineralization, as well as for collagen production. It activates ossification (the natural process of bone formation) by acting on both the protein content of the bone and its mineralization. The deficiency of this ion produces aging of the bone and a lower receptivity to vitamin D and parathyroid hormone.

  • Digestive system: Magnesium ion participates in the synthesis of digestive juices enzymes, as well as intestinal polypeptide hormones. It also stimulates the secretion of the pancreatic enzymes and activates various hepatic functions. Magnesium deficiency usually leads to gastric, intestinal, and hepatic disorders. 

  • Immune system: Magnesium acquires special relevance in the defense processes. It exerts multiple functions (anti-stress, anti-hypoxic, anti-allergic, anti-anaphylactic and anti-inflammatory). It stimulates phagocytosis and complements the regulation of acid-base balance, redox (oxidation-reduction) reactions, and thermoregulation mechanisms.

In addition, magnesium also plays a vital role in the reproductive system by intervening in genetic transmission in gametes and activating sperm motility. 

In pregnant women, it decreases the contractility of the uterus. 

An important aspect is the intervention of magnesium in the synthesis of surfactants in the lung, a fundamental substance in the respiratory process since it decreases the surface tension of the lung and facilitates breathing. 

On the other hand, magnesium is a preventive factor against cataracts and is an active ion in sight, hearing, and smell physiology. Our bodies can absorb only 45% of the magnesium ingested through food, while the rest is excreted. Absorption occurs in the small intestine and does not accumulate in the body.

The minimum daily recommendations are about 350 mg/day for adult men, 300 mg/day for women, and 150 mg/day for children. During pregnancy or lactation, the daily requirement increases up to a value of 400 mg/day. 

Final Word

Magnesium is one of the macrominerals playing a vital role in bone formation, cardiovascular health, sight, and immune system, among other functions. 

Nuts, legumes, green veggies, and whole grains are the richest food sources of magnesium that you can include in your diet. 

Magnesium is a vital mineral for the proper functioning of the body, it increases bone strength, thus reducing injury risk in high-performance athletes.