Minerals and Supplements in Summer: Tips for Every Sport

Here we go again: summer arrives and everyone talks about the importance of minerals as if we only needed them under a scorching sun. There’s some truth in this idea, because when we exercise, heat can deplete our mineral stores. Anyway, let’s clear things up:

 

What are minerals?

They are inorganic, calorie-free micronutrients that our body cannot synthesize and that we must therefore get through our diet.

The minerals contained in the human body make up over 5% of body weight and underpin various functions: structural support, osmotic balance and catalysis of metabolic processes.

We need an outside supply of minerals because they are eliminated every day through urine, feces and sweat, and so must be constantly replenished through the diet.

 

Where are they found?

They are present in our body in a solid state (crystals), in bones and teeth, and in solution, in intracellular and extracellular body fluids.

 

Which ones are there?

They can be divided into 3 classes:

– Major elements, whose requirement is measured in grams/day; these include the five macrominerals: Sodium, Potassium, Magnesium, Calcium and Chlorine, and six basic structural elements: Hydrogen, Oxygen, Carbon, Nitrogen, Phosphorus and Sulfur.

– Trace elements, whose requirement is measured in mg/day; these include Iron, Zinc and Copper.

Ultra-trace elements: 11 metals are recognized as essential: Chromium, Manganese, Cobalt, Nickel, Silicon, Arsenic, Molybdenum, Boron, Iodine, Fluorine, Selenium.

 

Don’t assume that their order of importance depends on the “quantity” required. Each element has its own function and metabolic role in relation to the amount needed, and each has symptoms of deficiency and symptoms of overdose. Each element is found in different food sources.

That is why the TV nutritionist of the moment always ends their segment by stressing the importance of varying the foods you eat and “coloring” your table with seasonal fruit and vegetables.

The statement “eat a bit of everything” may sound trivial, but it actually hides a complexity of factors that could hardly be unpacked in the rushed pace of television.

Moreover, the amount of minerals often doesn’t match the amount absorbed and used by our body. Bioavailability depends on the composition of the food. The minimum requirement results from a set of factors that depend on the individual, the type of diet and the environment the person lives in.

Do a 50-year-old obese man, a teenage girl, an amateur athlete who runs the marathon and a weightlifter have the same requirements?

The question is rhetorical and the answer is clear: no.

That’s because they start from different physiological conditions, different lifestyles and distinct goals.

An obese person lives in a state of constant dehydration compared with someone of normal weight; a teenage girl has a larger body surface area relative to body weight, higher heat production and a lower ability to regulate temperature in high heat; a marathon runner has a different physiological need and a different goal from a weightlifter.

This is to reiterate the importance of personalizing the meal plan and its supplementation, avoiding “do-it-yourself” approaches that, at best, bring no benefit without a targeted strategy.

Fortunately, for many of these elements we don’t even have to think about how to take them in: we get them constantly through breathing and food.

 

Let’s spend a few words on the need to replenish some of these, known as electrolytes, during sports activity.

The minerals that are essential during physical effort are Sodium and Potassium, which are usually found in a normal diet (fruit and vegetables).

Intense exercise causes a loss of electrolytes, sodium and potassium through sweat; supplementation may be needed only when losses are very high.

In addition, “thirst” is not a reliable indicator of how hydrated our body is. And after the age of 50 we lose the thirst stimulus.

Dehydration raises body temperature, which can result in fatigue and heat stroke.

The recommended amount of fluids for people who don’t exercise regularly is 1 ml of water per calorie; in other words, 1 liter of water for every 1000 calories consumed.

It increases during intense, prolonged exercise: in that case you need to hydrate in advance and keep drinking, starting one or two hours before the activity, especially if it takes place outdoors in the sun.

Drinking 500-700 ml of water and topping up with plain water every 15-20 minutes may be enough for most recreational athletes if, and I stress if, they start from an adequate fluid and electrolyte balance supported by a proper daily diet.

No supplement can make up for repeated nutritional deficiencies.

Individual fluid requirements vary with environmental conditions and the intensity of exercise.

After exercise, you need to replace every 0.5 kg of body weight lost with 500 ml of fluids.

For sports lasting an hour or less, water is the only thing needed to restore fluid balance.

For physical activity lasting longer than an hour and a half, drinking beverages containing salts and maltodextrins can help improve performance.

Salts are usually taken in the form of potassium and magnesium aspartates to prevent cramps, fatigue and muscle weakness.

The Potassium interacts with sodium and chlorine in the conduction of nerve impulses. Top-level long-distance athletes can run into a potassium deficit.

The Magnesium is essential for muscle contraction and nerve function: tics, tremors and muscle weakness point to a deficiency. Here too, though, “do-it-yourself” is not recommended. Taking it is contraindicated in cases of kidney or adrenal insufficiency.

The Sodium, one of the main electrolytes in the human body, is found everywhere in food and is often added during food processing, especially in industrialized countries.

1 g of Sodium is equivalent to 2.5 g of table salt. The WHO, the World Health Organization, suggests not exceeding a daily limit of 5 g of salt. It certainly doesn’t need supplementing.

The Chlorine regulates osmotic pressure and electrolyte balance. Since we take it in as chloride through the widely used table salt (sodium chloride, NaCl), it doesn’t need to be supplemented.

The Calcium is the most abundant mineral in our body: a good part of it is stored in the bones because calcium, combined with phosphorus, forms hydroxyapatite, the salt that builds our skeleton; but that is certainly not its only function: the calcium ion plays a role in nerve impulse transmission and muscle contraction, in enzyme function, in heart rhythm and in blood clotting. It is easy to understand why the amount needed is greater during development (infancy, pregnancy) and also in “old age”, because absorbing and retaining it becomes harder. One g/day is the average daily intake, and a varied diet that includes milk and dairy products doesn’t need supplementation.

I feel I must stress that every single element “works” in synergy with the others, and that a deficiency or surplus of one triggers another as our body searches for homeostasis.

By following the Eathlon® platform you can stay up to date on how diet and training positively affect your health, well-being and performance.

 

Author

PIERLUIGI VAGALI

Nutritionist (biologist), lecturer at the University of Genoa and the Alma Graduate School in Bologna, as well as a speaker at conferences across Europe on “Physical activity, well-being and Healthy Aging”. Strength and conditioning coach, manager and scientific consultant for the best-known fitness chains.