Physical Education Class 12 Notes Unit 2 Sports and Nutrition
→ Balanced Diet: A diet which consists oF all the essential Food ingredients viz., protein, carbohydrates, fats, vitamins, minerals, and water in correct proportion is called a balanced diet. It refers to the intake of edibles which can provide all the essential nutrients necessary For the growth and maintenance oF the body in a deFinite amount.
→ Nutrition: ‘Nutrition’ is the science oF Food that deals with the dynamic process in which the Food consumed is digested, nutrients are absorbed and distributed to the tissues For utilization and wastes are disposed-oFF by the body. Nutrients are the basic components oF Food that are essential For human beings to stay away From diseases and live a healthy and energetic liFe. There are basically two types oF nutrients: Macronutrients and Micronutrients.
→ Macronutrients: Macronutrients are the structural and energy-giving caloric components oF our Food that include carbohydrates, Fats, proteins and water. They constitute majority oF an individual’s diet and need to be taken in surplus amount.
→ Micronutrients: Micronutrients are the vitamins and minerals. They are required in small quantities, but possess great signiFicance For proper Functioning oF our body.
→ Nutritive Components of Diet: Nutritive components oF diet are those components which contribute or provide energy or calories. There are various nutritive components oF diet which are described below:
→ Proteins: Proteins provides the body with amino acids, which are the building blocks For muscle and other important structures such as the brain, blood, skin and hair. Proteins Form new tissues and repair the broken tissues.
→ Carbohydrates: Carbohydrate is also a compound which is formed by the chemical composition of carbon, hydrogen and oxygen. Carbohydrates act like a fuel in our body. They provide energy and are responsible for various digestive operations in our body.
→ Fats: Fats are stored in body and used as emergency sources of energy. They also helps in regulation of body temperature and play a vital role in protecting our vital internal organs.
→ Vitamins: Vitamin is also an important nutritive component of food just like proteins, carbohydrates and fats. Vitamins are very vital for healthy life. Vitamins protect us from various types of diseases. In fact, vitamins increase immunity power of our body ^ against diseases. They also give their important contribution for the general development of body. Vitamins are of two types— fat-soluble vitamins (A, D, E and K) and water-soluble vitamins (B and C).
→ Minerals: Our body contains more than 19 minerals which must be derived from food. However, they are required in small quantities. Main mineral salts found in the body are calcium, phosphorus, iron, magnesium, potassium and iodine. Calcium ^ and phosphorus help in the proper development of teeth and bones. Iron contributes to the formation of haemoglobin content of red blood corpuscles. Iodine helps in the prevention of certain diseases caused by Thyroid action deficiency.
→ Non-nutritive Components of Diet: Non-nutritive components are those components oF Food, which don’t give energy or calories. They do not have nutritional value and are added to Food and beverage products. They are designed to make the Food smell better, taste better, last longer and look better. Following are the non-nutritive components oF diet:
- Fiber of Roughage: It is undigested part oF Food which improves intestinal Function by adding bulk to Food. It is present in Fruits, vegetables etc.
- Water: The nutrients are transported to various cells oF the body with the help oF water. It also regulates the body temperature and is signiFicant in the excretion oF waste products.
- Colour Compounds: The Food is made more appetizing and attractive to see by colour compounds.
- Flavour Compounds: These develops better taste and odors to the Food.
- Plant Compounds: These components are present in plants and have been associated with protection or treatment oF diseases such as cancer, diabetes etc.
→ Healthy Weight: A healthy weight is that weight which lowers that risk oF various health problems such as heart diseases, stroke, high blood pressure, diabetes etc. and leads to a healthy liFe. .
→ Body Mass Index (BMI): It is a measure oF body Fat calculated on the basis oF height and weight. It is applicable to both adult men and women.
→ Method to Calculate BMI: IF you want to know your body mass index, then divide your body weight in kg
by the square oF your height in metre, i.e.,
_ , , , Weight in kg
(Height in m)^
The WHO criteria For underweight, healthy, or normal weight, overweight and obesity oF BMI are:
| Category | BMI |
| Underweight | <18.5 |
| Normal weight | 18.5-24.9 |
| Overweight | 25-29.9 |
| Obesity Class 1 | 30-34.9 |
| Obesity Class II | 35-39.9 |
| Obesity Class III | >40 |
The Pitfalls of Dieting: The major pitfalls of dieting are given below:
- Extreme reduction of calories
- Restriction on some nutrients
- Skipping meals
- Intake oF calories through beverages
- Under-estimating the calories
- Intake oF labelled Food
- Not performing exercises
→ Food Intolerance: Food intolerance is a term used widely For varied physiological responses associated with a particular Food. In simple words, Food intolerance means the individual elements oF certain Foods that cannot be properly processed and absorbed by our digestive system.
→ Food Myths: Food myths are beliefs about food that have no scientific base. They are circulated with the intention of promoting good health and healthy living. Though it is not possible to mention all the food myths present all over the world, some of these have been mentioned here:
- Potatoes make us obese
- Drinking water along with food makes us fat
Skipping meals reduces fat
- Fat-free eatables help lose weight.
- Consuming milk over fish is injurious to health.