Yogasanas are the physical practices which tone up the internal organs of the body. The body that is visible from outside is only a skeleton covered by muscle cells which gives it a shape. We also have provided structure of the human body and some other information about its internal functioning. Until and unless our internal organs are healthy, we cannot be healthy. We see that the heart works for all the 24 hours and does not take rest even for a single moment. The heart can get rest only when the nerves carrying the blood to and from the heart are clean. Even a small obstruction in them can cause a major disorder. Our lungs should also function properly and take maximum air full of oxygen for purifying the blood. Similarly our stomach, liver and other glands should secrete their full quantity of juices for the proper digestion of food. The intestines should also extract the maximum food elements from the food. The formation of juices, blood, muscles, fats, bones, semen should take place according to the needs of the body. Our nervous system should get strength so that all body movements can be performed in a proper way. The impurities should not get accumulated in the body and we should be able to enhance our muscle power.

Our body tells us everything. For instance, it tells us when it is hungry or thirsty or tired. Accordingly, we eat food, drink water and take rest. When the body does not require food, it vomits it out. It cannot keep any impurity inside it. What is needed is to give proper attention to it, to hear its call so that it remains active all the time.

But we generally do not pay attention to all this. When the impurity in the body takes the shape of a disease, we run for medicines. What does the medicine do? It usually numbs the nerve tissues which give information about the disease and we become satisfied that we have been cured, although the medicine has only suppressed the disease and not cured it.

It is said by medical experts that in the absence of regular exercise, a chalk-like impurity gets accumulated in the muscles and other body parts. It contains chemical substances like lime-phosphate and magnesia. For the human body, this impurity is like poison. As the age of a person increases, the amount of this poison also increases in such proportions that it is able to damage several parts of our body. By the accumulation of this impurity, the veins and arteries contract, the circulation of blood in the brain becomes slower, the memory is affected and doubts, worries, bad temper take hold of us. But, on the other hand, if we exercise regularly, we can get rid of this impurity thereby enhancing our physical and mental health and increasing our-life span.