Your calf twitches at night, training feels harder than it should, recovery drags on. Most of the time we blame the training load or sleep — but quite often the real cause is a mundane lack of magnesium. It’s a mineral of which the body stores only about 25 g, yet it takes part in the work of more than 350 enzymes.
Why magnesium matters for athletes
Magnesium helps supply the body with energy — it is involved in ATP production, muscle contraction and the transmission of nerve impulses. When blood magnesium falls below 0.45 mmol/l, heart and circulatory problems, nervous system disturbances and respiratory issues can appear. Studies carried out in several countries show that people’s daily magnesium intake is often below the recommended level.
An athlete’s need is higher. Intensive training means heavy sweating, and magnesium is lost from the body along with the sweat. Data from recent years suggest that endurance athletes in particular — runners, cyclists, skiers — should keep a close eye on their magnesium levels. If your results drop for no obvious reason or fatigue after workouts lingers, it’s worth considering a mineral deficiency before raising the training load even further.
People trying to lose body weight are also a risk group. Whether you’re a recreational athlete or a bodybuilder, a wrestler or a boxer — cutting calories lowers your mineral intake too. Reaching the desired weight is of little use if the mineral deficiency that comes with it undermines your performance and puts your health at risk.
Magnesium and the signs of deficiency
The most typical sign is calf muscle cramps. The first signal, however, is often a small twitch — a muscle tremor you may not even notice at first. Later, apathy, nervous irritability and heart rhythm disturbances can follow.
Honestly — in an athlete these classic symptoms may not appear at all. Instead, you catch yourself thinking that the workout feels harder, the last reps stay undone, your form slips away. The solution people often reach for is raising the training load, which only makes the problem worse. The only way to be certain is a blood test with a sports physician or family doctor. Once a low level has been found, it’s worth checking it regularly.
Magnesium in food and supplements
The first place to look is your plate. Foods rich in magnesium include green vegetables and salads, whole grain products, apples, bananas, soybeans, nuts and milk. Mineral water should contain at least 100 mg/l of magnesium — this information is on the bottle’s label, so it’s worth checking.
But the body doesn’t absorb everything in the same way. Magnesium absorption is inhibited by foods high in dietary fiber, calcium, phosphates, a lot of fat, protein and alcohol. A deficiency of vitamin B1 and vitamin B6 also interferes with absorption. That’s why a bowl of salad alone isn’t always enough — especially when your training volume is high.
The general recommendation is 300–400 mg of magnesium per day, but for people who exercise regularly, amounts of up to two times higher have recently been discussed. If food isn’t enough, supplements help. Because of slow absorption, magnesium carbonate forms are not recommended — citrate, malate or bisglycinate are better. In sport, it’s worth taking magnesium together with vitamin B6, which supports its uptake. The exact dose is decided by a doctor based on a blood test — the amount on the back of the package is a general recommendation, not your personal requirement.
FAQ: magnesium and training
Should I take magnesium before or after a workout?
The time of day matters less than regularity. Many athletes prefer the evening, because it supports sleep and muscle relaxation. If you use a form that irritates digestion (e.g. oxide), take it with a meal.
How quickly can a deficiency be corrected?
Cramps and twitches can subside within a few days, but fully restoring your stores takes weeks. That’s why you shouldn’t stop the course as soon as the symptoms disappear.
Is there a risk of overdose?
You practically can’t overdose from food — the kidneys excrete the excess. With supplements, too much can cause diarrhea. Keep the dose within a reasonable range and consult a doctor if you take medication.
Author: M.M.
Come and train! ArtGym
