Adding electrolytes (salt) is very important, and it is recommended that the most important effect liquids have on the body, during and after exercise:
- Lower heart rate
- Lower central part of the body
And water consumed, its temperature should be between 15 to 21°C. The factors affecting water absorption include:
- Sugar concentration
The more the concentration, the slower the absorption
- Liquid volume
The optimum absorption is 600 ml per time
- Water temperature
Colder drinks have higher absorption speed
- Activity severity
When activity severity becomes more than 60%, gastric liquid emptying speed is lower
Total energy consumed by an individual
- Energy received: is given to the body through foodstuffs
- Energy consumed: energy consumed during the day.
Energy consumed a day:
- BRM: fuel must without basal metabolic rate (BMR) of thermic effects of foodstuffs
- BRM: energy consumed when physical activities
Long-term hungers lower BMR time (e.g., body metabolism decreases)
Exercises in older and younger can increase BMR.
During exercise, as well as one or two hours after exercise, BMR increases:
One atrophies 7000 kcal (1 kg).
One battens 7000 kcal (1 kg).
BMR in men is about 5 to 10% less than that in women.
What factors increase BMR?
- As fat-free mass of the body is higher, BMR is higher. Weightlifting (in order that muscles volume increases).
- Length: the more the height, the more BMR.
- Age: the less the age, the more BMR.
- Increased levels of thyroid hormone
- Stress increased BMR level
- Sex: men have higher BMR
- Pregnancy: when pregnancy, BMR increases.
- Caffeine: tobacco increases BMR.
Factors decreasing BMR
- Decreased muscle mass of the body
- Individuals with short stature
- Individuals with more age
- Long-term hungers and fast
Thermic effects of foodstuffs
- When the meal is fatter, it increases body metabolism by 5%.
- When the meal is full of carbohydrates, it increases body metabolism by 10%.
- When the meal is full of proteins, it increases body metabolism by 20%.
And on average, a mixed meal increases body metabolism by 7-10%.
Digestion and food consumption scheduling:
In general, most of the main substances we consume are carbohydrates and water.
Carbohydrate + water
There is a delay in the body, since food enters the body until it is absorbed by the body.
Gastrointestinal problems during exercise
- If one starts exercise with a full stomach, there will be gastrointestinal problems during exercise
- Their exercise status: less exercise increases gastrointestinal problems.
- Mental stresses
- If activity severity is less, the body can achieve absorption and digestion
- With high severe activity, absorption and digestion decrease due to our blood circulation
- Body water absorption level
- Type and concentration are also effective.
Main goal: nutrition before competition
- Liquids are given sufficiently and properly to the athlete
- Provide carbohydrate reserves for liver and muscles
- Prevent hunger from occurring during exercise
- Minimize gastrointestinal problems
- Make the stomach be nearly empty when exercise
Recommendations about nutrition before competition
- The meal should contain carbohydrates, proteins, and fats in order of priority.
- The meal should contain high volume of liquids.
- A meal with carbohydrate is very crucial for long-term resistance exercises.
- Carbohydrates are discharged very quickly from the stomach, and sugar substances are easily provided to muscles (macaroni, lentil, potato and … have a rapid digestion).
… before exercise is water retentive.
Approximate value of carbohydrate before competition
About 2 to 3 hours before exercise, it is recommended that 1 to 2 gr of carbohydrate per 1 kg of body weight, is consumed.
Carbohydrate consumption during exercise
In resistance exercises, about 30 to 60 gr of carbohydrates should be supplied through drinks (honey, sugar water, date syrup)
With a severe exercise, carbohydrate should be supplied by 90% per hour, through drinks.
Before and after exercise, sugars with high Glycemic index should be consumed.
Recommendation immediately after exercise
At the first 1 to 2 hours:
1 gr / 1 kg of body weight, mostly as energy liquids and drinks with high Glycemic index (e.g. a soup with mashed potato and or noodles … in it)
High severe exercise:
Within 24 hours after the end of exercise, 7 to 12 gr of carbohydrates per 1 kg of body weight should be consumed.
The time for food digestion and absorption in the stomach is usually 3 hours enough so that the food exits the body.
And generally, full vacation of stomach: after 3 to 4 hours after eating the meal, the foodstuff should exit the body.
For such exercises as boxing, wrestling, rugby, the stomach must be fully empty before competition.
A competition before which one can not eat the meal by within hours, for example, the competition to be held at 8:00 o’clock
- The last meal is very important, e.g. dinner.
- A light breakfast before exercise. For this purpose, one should consume foodstuffs as liquids and carbohydrates (e.g. natural juice is the best drink)
- The best thing is that one goes to sleep early at night and wakes up early at 4:00 (this should be done for a week so that the body acclimatizes).
Shortage or lack of appetite in athlete (before competition).
The main factor is mental stress. In this case, the individual has not appetite for foodstuffs. This case must be changed as soon as possible. If not, the individual should consume liquids and drinks, or is administered by sugar and salt serum.
The most important causes of food consumption during competition
- Keep blood sugar level
- Keep body’s liquids
- It is very obvious at the end of exercise
In some cases, it is observed that the sugar substance which is consumed keeps blood sugar and stories glycogen in the liver.
- Anorexia due to exercise
Negative point: If it does not compensate the most part, one will have problem with the next day’s competition.
Positive point: those who seek to have weight loss, ….. If the exercise term increases, one’s anorexia becomes more.
Nutrition of Tennis Athletes
Tennis is among anaerobic exercises because, although tennis players make exercises for a long time, during this term, their physical activities are in the form of rapid movements requiring anaerobic systems to supply energy. Therefore, setting food plans for this group of athletes must be in such a way that energy reserves, especially for anaerobic systems (glycogen), when the athlete enters the tennis court, are in a desirable level. Based on the above, food plan for a tennis player, especially during competitions, must contain high energy so that it supplies water reserves and electrolytes needed for the body.
Food Plan before Competition
Tennis players must pay special attention to their food plan during this term, particularly the meal before their competitions, because having a desirable food plan during this term, will supply nutrients, energy and liquids needed for them during competition. In fact, except in special cases, the food plan for the athlete during this term is similar to diet of a normal individual, in which the amount of foodstuffs consumed by the individual is more, and so called, composed of more nutrients. During competition period, the amount of nutrients and energy needed for the individual vary depending on number of hours and his / her severity of exercise. However, in this period, the athlete must observe the principles of correct nutrition such as balanced consumption of salt, fat, simple sugar, and put the consumption of appropriate amounts of vegetables and fruits in the agenda to prevent from chronic diseases.
During the period before competition, the amount of nutrients and energy required for the individual vary depending on his / her number of hours and exercise severity. In addition, because of body building exercises and plans for weight loss or increase during this term, food plan and food combinations will be very different.
Changes in Weight
During rest period, and among competition seasons, due to change in physical activity as well as food combination received by the individual, weight loss or increase of the athletes in many sports fields including tennis are common. Although like sports such as wrestling, tennis is not played in specific weight limits, weight increase in these individuals can decrease their sports-movement strength, and weight loss also can accompany with muscle tissue drop, and thus decreasing the individual strength.
Carbohydrates and fats are the principal sources of energy during exercise. However, carbohydrate and water are the only nutrients needed to be consumed when playing tennis. For some players, salt consumption during playing tennis is recommended to keep liquids balance and prevent cramp associated with high temperature.
Even if the player eats a good meal at night before competition or game, within 60 to 90 min after starting the competition, carbohydrate stored in his / her body decreases considerably. This usually leads to blood level drop, and as a result, the player performance decreases, and he / she feels fatigue sooner. Thus, consumption of carbohydrates during competition is necessary. Most of adult players retrieve by 60 gr of carbohydrates through drinking 1 l of carbohydrate-electrolyte drink.
Carbohydrate-electrolyte drinks can have different advantages compared with water:
1) Supply energy as carbohydrate.
2) Delay starting of fatigue.
3) Encourage the player to drink more
4) Provide electrolytes which help to keep the balance of inorganic materials and liquids.
All of these factors are important in maintaining performance, especially when you play in a warm climate (in warm weather, carbohydrates are consumed sooner, and player body water decreases due to high sweating). Sports drinks produced for being drunk during the competition, which must not be confused with energy drinks, are not suitable for competition at all, and their carbohydrate concentration should be 5 to 7%. This means that for any liter consumed, the player naturally consumes about 50 to 70 gr of carbohydrate. More concentration (higher than 10%) will reduce the stomach empting rate, which in turn, delay carbohydrate and water entering blood circulation.
When the player’s consumption, during a one-hour competition, becomes more than 1 l, it would be advisable that consumption of sports drink and water is shifted alternatively. Drinking sports drink singly (even if the amount of carbohydrate available at it is 5 to 7%), in a high volume (e.g., 1.5 to 2 l / h) may disturb the body, because many carbohydrates enter the body. Entering high fructose (through sports drinks or ordinary meal) to the body can lead to gastrointestinal problems. This is why fructose is absorbed more rapidly than other carbohydrates existing in sports drinks. The athlete can use snacks easily absorbed by the body during competitions and exercises, in order to strengthen his / her energy.
If the player sweats highly (e.g., more than 2 l / h), shortage of liquids may not be prevented. However, adolescents and adults can drink by 1.4 l / h drinks with electrolyte. This amount can solve shortage of liquids in most of individuals. On the other hand, if the player is susceptible to cramp, he / she may add some salt (one forth of teaspoon) to his / her sports drink.
It is better for the athlete to have a suitable weight limit depending on his / her length. This weight must be achieved through a body building process, and weight loss or increase is avoided during competitions, because changes in weight during competitions is made by wrong and hasty ways, so that it damages the individual’s performance irreparably. To achieve a food plan suitable for an athlete, first, based on such factors as weight, length, sex, and age, the energy and nutrients needed for him / her is determined and then, depending on his / her physical activity and willing for weight loss / increase, the energy required by him / her is obtained.
The Meal before Competition
- This meal has an invaluable role in supplying energy reserves and liquids needed for the body of an athlete during competition.
- This meal is consumed 3-4 hours before competition, and includes some easily-digested foods, preferred by the athlete.
- At least 60% of energy in this meal must be supplied by carbohydrates (starch compounds). Overall, this meal needs to contain high carbohydrate, middle protein, and low fat. Accordingly, macaroni, bread, fresh fruits, and drinks with carbohydrates are included in this meal.
- In this meal, it is necessary that there are foods familiar with individual’s taste, and testing new foods in it is avoided as possible.
- Consumption of bulk food, due to their difficult digestion, should be prevented before and during exercise.
- Avoid from eating fatty and fried foods, because they are digested difficultly, and may cause gastrointestinal problems during exercise.
- High-fiber foods should be omitted from this meal, because these compounds cause gastrointestinal problems and bloated stomach.
- If you are nervous, or have gastrointestinal problems, consume your meal before competition, as liquids. For information about the best compound in this meal, consult the team’s nutrition expert or counselor.
Supply and Complete Water Reserves Needed for the Body of An Athlete
- An athlete must drink sufficiently. The simplest criteria for determining whether liquids consumption is enough or not, light color of the individual’s urine.
- At the beginning of competition, any tennis player has to prepare at least 2 liter of sports drink, and have it ready for drinking during competition.
- Avoid from drinks containing caffeine such as various colas and coffee, because these drinks reduce water reserves of the body of the athlete, through increasing urination.
- Within two hours before competition, any person must drink 500-600 cc (2-2.5 glasses) of various liquids.
- During physical exercise, consumption of water and or sports drinks to supply his / her liquid reserves lost, is recommended. Feeling of thirst is not a good sign for taking drink during this term. It would be advisable to drink liquids continuously about 100 cc for every 15 to 20 m.
Nutrition at the end of competition:
During this term, foodstuffs and liquids should be consumed to supplement the individual’s lost reserves as rapidly as possible. In fact, observance of some principles mentioned below, accelerates rehabilitation of the athlete, and makes him / her ready for keeping his / her daily activities and or for the next competition.
The following things must be followed by tennis players:
- Immediately following competition, within 30 m after that, begin to take sports drinks. It is preferable to consume sports drinks as soon as you exit the tennis court.
- During the first two hours after competition, per a kilogram of the weight lost, take 2.5 glasses of water and or sports drinks.
- The first meal to be eaten following the competition, should be selected among from the foods with high carbohydrates to help reconstruction of glycogen reserves of the individual’s muscles.
Special Beliefs on Nutrition
Certain individuals have special beliefs about nutrition, some of which may be wrong and harmful. Such nutrition beliefs are particularly common about dieting, and can cause damages to the individuals’ health. Understanding these beliefs and attempt towards changing them will be an effective step taken in improving nutrition in the society. One of these beliefs is that eating breakfast fattens us, thus we should avoid eating breakfast not to become fat. This belief is not only correct, but also can cause serious damage to our health, because breakfast is not only the most important meal but also one of the most necessary meal for us. Never delete breakfast. Another wrong thing some individuals believe in is that eating pickled fruits together with the meal can eliminate fats and, as a result, causes weight loss and atrophy. Sour materials help fats to be absorbed, and consequently, increase fats in the body.
Why do we use computer for weight loss dieting? Because the diet suitable for any person is provided in proportional to age, weight, length, sex, activity rate and … Food variety as well as change in diet in proportional to weight loss and too much mathematical calculations in weight loss diet, have given rise to use computer in order to decrease errors. However, finally, supervision by the physician on the diet and following his / her instructions by the dieter, and supplying all vital needs for the body will guarantee a diet to be successful.
Note: the diets prescribed, will be provided depending on your full health. In case where you have a special disease (e.g. diabetes, blood pressure, kidney, liver, gastrointestinal and etc …), inform your physician of it so that he / she can prescribe a suitable diet, and your meal is eaten accordingly.
Note: many individuals take diet continuously and return to ordinary diet. These individuals loss dozens kilogram weight and their weight increase again. Dieticians recommend that if you have not enough will for decreasing and keeping your weight, prevent from frequent pick-ups and drop-offs.
Ways for Strengthening Will for Weight Loss Diet
- It is important to consult your physician so that you can remove all uncertainties.
- Take the complications of obesity into account.
- Strengthen your will by religious vows.
- Pay no attention to compassion from those around, about low eating.
- Consider a small spoon for yourself with which you eat.
- Choose a special place for eating.
- Eat slowly.
- Ask those around for noticing your inattentions to diet.
The following is some points about diet:
Note that diets are planned according to your personal particulars. Never prescribe them for others.
Depending on its type, a diet may be difficult at first, but after two weeks, you will find it very easy.
During the first month, try to follow exactly the diet prescribed. Since the second month, when you learned how to substitute the meal, you may make any change in your diet deliberately. For example, if you are to receive 675 cal, for dinner, through eating 4 cutlets and 30 gr of bread, and you went to parties where there is nothing rather than chicken and cooked rice, you can eat cooked rice, a chicken thigh, a drink, instead, to supply the same 675 cal. You will learn this gradually during the diet therapy sessions. Here, you will find that long diets are more successful because both there is enough time for changing diet behaviors and your body has not to tolerate hard diets.
The following foods are free in an ordinary diet, and you may use them to any extent you want: vegetables, lettuce, cucumber, turnip, tomato, cabbage, carrot (not carrot juice), sauce-free salad (lemon juice and verjuice are okay), radish, spinach, water, salt, vitamins, onion, scallion, tea (without sugar), boiled pumpkin, boild green beans, parsley, and all other vegetables such as rhubarb, poached mushrooms, sugar-free drinks.
Use of carrot during the day is much recommended, particularly when you are hungry.
The best oil to be used is olive oil, and vegetable oil is the best in order of priority.
In a diet, bread size (as small as a palm) is equal to 30 gr of bread, depending on the type of bread.
Fruit size: Fruit used in a diet refers to a mean apple, orange, chino, peach, grape fruit, two mean tangerine, two kiwis, two persimmons, half a banana, three figs, four dates, three apple accessories, one glass of strawberry, a glass of prunus, a glass of cherry, a glass of sour cherry, one and a half glass of watermelon or cantaloupe or melon, four apricots, four medlars, half a big pomegranate, half a navel orange. So, where you find fruit in your diet, you can substitute it for one of the above (each of the above has 75 calories). Cucumber and carrot can be used freely.
Meat size: A chicken thigh refers to a thigh of a 1.5-kilogram chicken. Chicken breast refers to a breast of chicken without wings and skin. A piece of fish refers to a fish of 17 × 17 cm. if you have precise scales at your disposal, follow these weights: mutton, 75 gr; chicken, 12 gr; and fish, 230 gr.
Sugar size: Sugar cubes of 2.5 gr, equal to 10 cal.
You may substitute the meal together. For example, lunch for dinner, breakfast for evening meal, and or Saturday for Sunday.
A skimmer of cooked rice refers to 6 tablespoons of cooked rice as paddy rice, or 7 tablespoons of drain rice. However, it would be advisable to cook paddy rice.
Those who do not use sugar cube, can eat the following substitutes:
A sugar cube = 2.5 gr = 10 cal = 6 dried berries = 6 currants = 12 raisins.
Two sugar cubes = 1 date.
Three sugar cubes = 1 chocolate
Substitutes for bread: a palm of bread = 30 gr = 5 mean biscuits = 2 biscuits with cream = 3 digestive biscuits = a potato = a fruit = 3 tablespoons of cooked rice = 2 Danish pastries
Milk: a glass of milk = 200 cc of low-fat milk = 110 cal = a glass of yoghurt
Cutlet, meatball, coco, dish of tomato: each has 200 calories on average, and can be substituted for each other.
Pizza: half a pizza = a sandwich = two skewers of grilled liver and a bread = a skewer of shish kebab and a bread = two eggs and a bread
Never use the substitutes within one month. Since the second month, the principal diet takes priority, and use the substitutes only when you go to parties and on a trip.
If you diet is to be last two weeks, never measure your weight until the end of the diet.
Your diet may last for several months, depending on the conditions. However, you should not have weight loss more than one kilo a week.