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Indoor sport: develop the right nutritional habitsThere are now very many fans of strip floors, dojo, fitness rooms or gymnastics that regularly do indoor sports. Diet has an active role in sporting success. So if for you "sport" means "indoor", winter as in summer, find out how to optimise your diet when playing your favourite sport.
Just because it takes place indoors, indoor sport sometimes gives some people the illusion that warming up or specific preparation are not required. Don't be so sure, it's important to prepare your body well before a game, fight or exercise. Below you can find out the advice offered by the Isostar nutritionist specifically for indoor sports.
Starchy foods with every meal
Like all sportsmen and women, you must favour a varied and balanced diet including at least 4 meals per day. Plan a snack as necessary either before or after training. More than 50% of you daily energy requirements must come from the "bread, cereals, potatoes and dried vegetables" group (bread, pasta, rice, semolina, cereals, lentils, etc.). Remember to include them in every meal, alternating whole wheat and refined flours to get the benefit of the fibre.To help recovery between matches or fights, give priority to easily-digested foods with a medium or low glycaemic index such as fruit, a cereal bar or a mini-sandwich. The glycaemic index (GI) measures the speed at which carbohydrates (sugars) in a food are absorbed over a period of 2 to 3 hours. Medium or low GI foods release energy progressively and thus avoid a rapid increase in blood sugar level and the drained feeling that often results due to secretion of insulin. Note: the GI of foods fluctuates according to the type of food, cooking and the presence of associated fibre or lipids. A chocolate flavoured bar has a medium GI because the chocolate contains sugar and fats.
Table 1. Glycaemic index of a few foods :
| HIGH GI | >75 | MEDIUM GI | 50-74 | LOW GI | < 50 |
|---|---|---|---|---|---|
| Glucose | 100 | Carott | 71 | Chocolate | 49 |
| French bread | 95 | White sandwich bread | 70 | Cake, pastry | 47 |
| Quick-cook rice | 91 | Chocolate flavoured bar | 68 | Sponge cake | 46 |
| Waffle | 76 | Pineapple | 66 | Whole grain bread | 45 |
| Croissant | 76 | Semolina | 65 | Apple muffin | 44 |
| Chipped potatoes | 75 | Ice cream | 61 | Orange | 43 |
| Honey | 73 | Potato | 62 | Apple juice | 41 |
| Watermelon | 72 | Orange juice | 57 | Spaghetti | 41 |
| Sugar | 65 | Crisps | 54 | Apple | 36 |
| Basmati rice | 59 | Banana | 53 | Yoghourt | 14-33 |
Source: Martin et al. Recommended nutritional intake for the French population. 3rd edition.
Team contact sports: faster, higher, stronger...
Repetitive movements (running, jumping, throwing) and lots of changes of rhythm are specific to team sports played indoors, such as handball, basket ball or volley ball. With each jump or on landing, for example after a smash, the body tolerates a considerable thrust that may be as much as 15 times its weight. These impacts, which are felt by the muscles and feet, can cause muscular micro-lesions that sometimes accompany intercellular haemolysis (damage to red blood cells with the release of haemoglobin into the blood plasma). The micro-lesions cause breakage of cell membranes and can lead to haemoglobinuria (loss of blood in the urine) and lead to iron loss. Remember to eat foods rich in iron regularly (offal, red meat, etc.).Diagram 1 describes urinary losses of iron in sportsmen and women.
Hydration: watch out for heat stroke
Overheated halls, long periods waiting between tournament matches of fights, all these things can influence water intake and contribute to dehydration. Sportsmen and women are recommended to drink about 2 to 3 litres of water per day. Always take water with as well as an appropriate isotonic exercise drink to help recovery between matches. Choose a drink that combines both carbohydrates and proteins in the ratio 6/1, such as Isostar Total Performance. Specially designed to enable sportsmen and women to accelerate recovery and reduce sensations of fatigue, it acts on three levels:- restoration of muscular glycogen reserves,
- preservation of muscle integrity,
- and reduction of muscular micro-lesions resulting from intense exercise.
Fruits and Vegetables: powerful anti-oxidants
Fruits and vegetables must also be eaten at each meal because they are especially rich in water and micro-nutrients important to sportsmen and women: anti-oxidants (vitamins C and E, β-carotene, carotenoids, flavenoids). These are precious allies against free radicals - highly reactive molecules that are formed in the body in contact with the oxygen that we breathe. These molecules promote premature ageing of cells and development of certain diseases. Certain situations contribute particularly to the production of free radicals in the body, such as: stress, fatigue, smoking, alcohol and atmospheric pollution, but also intensive physical exertion that requires a significant amount of oxygen.Tomatoes, carrots, onions, broccoli, leafy green vegetables, apples and red fruits are the most important sources of natural anti-oxidants.
Isostar nutritionist, November 2006.