Vitamins and minerals
Minerals such as iron, zinc and chromium are associated with energy production mechanisms.
Iron plays an important role in transporting oxygen from the lungs to the tissues. The first symptom of anaemia (iron deficiency) is general tiredness, with a drop or plateau in performance.
Intense practice of a sport can result in sportsmen and women having an unbalanced diet (by favouring certain food groups more than others) and thus developing a mineral deficiency. It is also important to meet requirements for vitamins B1, B2, B6 and niacin adequately, as these are needed to enable the cells to use carbohydrates properly.
- those bound by restricted diets (< 1500 kcal/day) associated with intense training: dancers, gymnasts, stable boys/jockeys,
- those worried about staying thin,
- those subject to weight categories: combat sports (boxing, Graeco-Roman wrestling, judo), etc
- oxygen transport
- part of energy metabolism (co-factor for more than 300 enzymes),
- neuromuscular function,
- transmission of nervous influx
Intense training can reduce the magnesium level of the blood. A magnesium deficiency in the blood (hypomagnesaemia) is manifested as great physical and mental tiredness, possibly with cramps (extensor muscles) and pins-and-needles.
- ambient temperature,
- inadequate magnesium intake (emphasis on foods with low nutritional density)
- excessive consumption of simple sugars,
- excessive protein intake.
Recommended nutritional intake is at least 400 mg of magnesium per day.
- formation of red corpuscles,
- chronic fatigue,
- increased production of lactic acid by the body.
Chronic deficiency is evident in nearly all endurance sportsmen and women (athletes), less frequently in team sports (except in women).
- inadequate intake: food dislikes, Ramadan ...
- low daily energy consumption,
- reduced intestinal absorption (for endurance sports),
- increase in iron losses (intestinal haemorrhages, perspiration, urine) through:
- use of inappropriate shoes or soles,
- exercise when fasting,
- taking Steroidal or Non-Steroidal anti-Inflammatories, or aspirin.
Recommended nutritional intake for men and women: identical to that for the non-sporting general population (10 mg per day for men, 18mg per day for women).
Note : all contact sports increase the iron requirement (physical impacts). Pregnant sportswomen must monitor their intake before and after pregnancy, as should those wearing an IUD coil.
- regulation of cell membrane activity,
- muscular contraction,
- neuromuscular excitation,
- formation and maintenance of teeth and bones,
- blood clotting,
- co-enzyme for numerous biochemical reactions.
- reduced bone density, osteoporosis,
- tetanic convulsions,
- tiredness, insomnia,
- amenorrhoea (loss of bone mass between 8 to 20% is then observed),
- inadequate intake of energy and proteins,
- vitamin D deficiency,
- hormonal dysregulation,
- inadequate calcium intake (eg. if allergic to lactose),
- calcium absorption or fixation problems,
- excessive urinary loss of calcium
Some dietary elements of factors inhibit the absorption of calcium (phytic and oxalic acids, excesses of coffee and alcohol, tobacco), others promote it (citrates, lactose, phosphorus, vitamin D, proteins).
Note: be careful of calcic mineral waters rich in sulphates, which seem to lead to increased calcium in the urine.
Recommended nutritional intake: identical to the general population, namely 1000 mg of calcium per day in males, and 800 mg per day in women.
Intake should be greater (1,200 mg per day) for post-menopausal women, women with amenorrhoea and teenagers.
VitaminsStudies are unanimous: vitamin requirements increase when practicing sport.
- co-factors for numerous enzyme reactions associated with energy production and protein metabolism,
- anti-oxidant vitamins (A, C, E) contribute to preserving tissue integrity in the face of free radical production (produced in large quantities during endurance exercises and in hypoxic situations).
|Activities||vitamin requirements||Additional vitamin intake|
|Leisurely||Varied and balanced diet
|Intense||Higher||Depending on the discipline and energy expenditure: exercise drinks, enriched in several water-soluble vitamins or supplements without overdosing.|
|Endurance||Increase in vitamins B1, B2, niacin, B6, C, E, beta-carotene|
|Strength||Increase in vitamins B6 and anti-oxidants|