Written by Ioannis Nikitidis, Medical Doctor, Dietitian and Nutritionist
Magnesium (Mg) is one of the most abundant minerals, specifically the second after potassium and serves as a co-factor in hundreds of enzymatic reactions, including energy production. (1) Magnesium is an essential element that regulates membrane stability and neuromuscular, immune, cardiovascular and hormonal functions and is an important cofactor in many metabolic reactions. Therefore, magnesium is a factor playing a key role not only pre- and during exercise but at the recovery period as well. The Dietary Reference Intake (RDI) for magnesium for adults is 310(females) to 420(males) mg/day. (2) Some of the most common food sources of magnesium are: Pumpkin seeds, wholegrains breads and cereals, green leafy vegetables, lean meat, legumes, nuts, milk, yoghurt and tofu. (3)
Clinical signs of hypomagnesaemia
Early signs of magnesium deficiency include nausea, fatigue, loss of appetite, vomiting and weakness. As magnesium deficiency worsens muscle contractions, cramps, seizures, sudden changes in behavior caused by excessive electrical activity in the brain personality changes, abnormal heart beat and coronary spasms might occur. (4)
The relation between magnesium and relaxation after exercise
Magnesium reduces the release of acetylcholine at the neuromuscular junction. Additionally, it causes reduced excitability of nerves and acts as an anticonvulsant. (5)
According to a 2012 study, magnesium deficiency may cause aggressive behavior, depression or suicide. Magnesium calms the brain and people do not need to become severely deficient in magnesium for the brain to become hyperactive. It is considered as an important mineral for relieving stress. The more stressed you are, the more magnesium is lost, and when the magnesium level gets lower, the stress level gets higher.
There are researchers supporting that magnesium is the most effective natural antidepressant. Furthermore, magnesium eases anxiety, improves sleep and stabilizes mood. There are studies reporting that individuals with anxiety have been found to have lower levels of magnesium. This may be linked to the fact that a magnesium deficiency causes the release of adrenalin. (6)
Magnesium and the Heart
There are studies showing that magnesium supplementation prevents and manages hypertension and cardiovascular disease. Specifically, after magnesium supplementation symptoms of palpitation, low energy, anxiety, chest pain, faintness and breathing difficulties were considerably reduced. Another study has shown that magnesium intake resulted to significantly improved systolic and diastolic blood pressure. (6) According to a 2013 study, magnesium supplementation resulted to lower resting and recovery systolic blood pressure after aerobic and resistance exercise. (7)
Magnesium is involved in terminating contraction and initiating relaxation in skeletal muscles. Magnesium critically stabilizes enzymes, including many ATP-generating reactions. ATP is required universally for glucose utilization, synthesis of fat, proteins, nucleic acids and coenzymes, muscle contraction and others. (4) Therefore, excessive plasma concentrations can cause muscle weakness. (6) In a recently published article (2016) researchers concluded that magnesium is effective in relaxing airway smooth muscle contractions. (8) Moreover, strenuous exercise usually causes pain. Magnesium supplementation possesses analgesic properties, helping the body relax after exercise. Thus, doctors use magnesium to decrease the need of rescue analgesics after spinal anesthesia. (9) The potentiating effects of magnesium on perioperative analgesia and muscle relaxation have drawn much of attention during the last years and anesthesiologists use it to reduce the use of anesthetics during and after surgery. (10)
Magnesium is involved in numerous body’s functions. Exercise increases temporary the blood pressure, heart rate and might cause some pain due to the muscle damage. Magnesium is essential to help you relax, lower your blood pressure and provide a sense of relief after your training session.
The importance of magnesium in post workout relaxation
~ Written by Ioannis Nikitidis, Medical Doctor, Dietitian and Nutritionist
3) Dr Louise Burke & Greg Cox. The complete guide to food for sports performance - Peak nutrition for your sport. 3rd Edition, Allen& Unwin, 2010