CBSE Class 12 Physical Education Sports And Nutrition Notes Set B

BALANCED DIET AND NUTRITIVE COMPONENTS

• Nutrition : Nutrition is the science of food which deals with the dynamic process in which the food consumed is digested.
• ​​​​​​​Balanced Diet : A diet that contains right amount of carbohydrates, proteins, fats, minerals, salts, vitamins, roughage and water is called a balanced diet.
• Roughage : The fibre present in the food which helps to eliminate wastes from the body.
• ​​​​​​​Elements of Diet : A diet which contains all the foodstuffs necessary to maintain good health consists of Carbohydrates, Proteins, Fats, Minerals, Vitamins and Water.
• ​​​​​​​Water : Almost two-third of our body is made up of water. Water helps our body to work well and maintain our body temperature. We need to drink at least 10-12 glasses or approx. 6-7 litres of water every day.

EFFECTS OF A DIET ON THE PERFORMANCE AND EATING FOR WEIGHT CONTROL

• Role of diet in performance : A proper diet is essential for good performance. The total energy requirement for a person engaged in physical activity ranges from 3500 to 6000 calories. Diet mainly aims to improve performance. It improves body composition and increases strength and speed. To identify the role of a particular diet, it would be better to be familiar with the role of vital nutrients on performance. The vital nutrients are discussed below :

(i) Carbohydrates : Carbohydrates are the chief fuel for muscular contraction. Studies suggest that carbohydrates helps in increasing the endurance of sports persons. Athletes should not be given carbohydrates in excessive amount, as it may be risky for them. Low level of carbohydrates generally leads or results in exhaustion.

(ii) Fats : For a distance runner, high jumper and a gymnast, a minimum amount of fat is desirable.
These athletes need nominal fat because, if they put on weight, it will hamper their performance.
Distance swimmers need a particular amount of fat distributed close to the skin surface to reduce the heat loss to the water.

(iii) Proteins : Proteins are essential for growth and development of various tissues of the body. If fats and carbohydrates are obtainable, they are preferred over protein, as the supply of energy.
Presently studies suggested that protein helps in the growth of lean tissues but does not have any major effect on performance.

(iv) Vitamins : In the normal diet for good performance in work and sports, vitamins are essential, but there is no prominent evidence that additional quantity of vitamins improves the performance. As a matter of fact, body is not able to store the large amount of vitamins; the majority of the excess
quantity of vitamins is excreted through the urine, giving only extra work to the excretory organs.

(v) Minerals : It is well identified regarding minerals, their quantity can decrease in hot climate. Sweating reduces the amount of sodium and chlorine in the body. Excess quantity of salt consumption can lead to potassium loss and increased water retention.

• Healthy Weight : A healthy body weight is a weight at which the body functions most efficiently and effectively, affording maximum protection against illness and disease.

• Pitfalls of Dieting : 

(i) Extreme reduction in calories : The intake of calories is reduced tremendously for dieting. If intake of calories is reduced, it results in sudden weight loss.

(ii) Restriction in some nutrients : Some nutrients like carbohydrates and fats are restricted in dieting,which can lead to improper functioning of the body. 

(iii) Skipping meals : If meals are skipped, it lowers the metabolism to preserve energy.

(iv) Intake of calories through drinking : To lose weight, most probably more stress is on not to eat more and not on what to drink. As a fact, beverages like coffee with cream and sugar, sweetened juices and sodas really add to weight gain.

(v) Not performing exercise : If an individual does not perform exercise and goes on dieting, it will not work properly. In place of losing weight, possibility is likely to gain weight.

• Food Intolerance : Food Intolerance means the individual elements of particular foods that cannot be correctly processed and absorbed by reasonable amount of the food but if eaten in a large amount or too often, individual gets symptoms of food intolerance because the body cannot tolerate unlimited
quantities.

• ​​​​​​​Food Myths : Numerous food myths exist not only in India but also all over the world as they sound like they could be true. The most common food myths which are still widespread in our modern society are given below :
(i) Potatoes make you fat.
(ii) Eggs increase cholesterol levels, so avoid them.
(iii) Drinking while eating makes you fat.
(iv) Starve yourself if you want to lose weight.