Sumit was a tireless bundle of energy. He was always up to some mischief or the other. As he grew, to his mother’s relief he became a more relaxed child, and over the years his energy level seems to have come down considerably. However, now he feels tired and fatigued. At times he wonders why he gets so tired so soon when there is so much that he wants to do?

What is it in our body that causes fatigue? Why do we feel listless and sapped of strength at times? Fatigue is caused by a kind of poisoning produced by our organs. When a muscle in our body works, it produces lactic acid. If we remove the lactic acid from a tired muscle, it is able to start working at once.

Why do we get tired?
Why do we get tired?

There are other substances the body produces in the course of muscular activity. These are known as fatigue toxins. Blood carries these toxins through the body, so that not only the muscle itself but the entire body and especially the brain, also feels tired.

Scientists have conducted interesting experiments on fatigue. If a dog is made to work until it is exhausted and falls asleep, and its blood is then transfused into another dog, the second dog will instantly become tired and also feel sleepy. Similarly if the blood of a wide-awake dog is transfused into a tired, sleeping dog, the latter will wake up at once and no longer feel tired.

But fatigue is not just a chemical process; it is also a biological process. We cannot just ‘remove’ fatigue; we must also allow the cells of the body to rest. Damages must be repaired, nerve cells of the brain must be ‘recharged’, and the muscles need to relax and unwind.

Very often, the best way to make a tired body part feel fresh again is to make other parts of the body active. We can actually rest by means of activity. Activity increases the respiration. The blood circulates faster, the glands are more active, and the waste products are eliminated from the tired parts of the body.

But, if you are totally exhausted the best thing to do is sleep. Sleep is a great vitaliser and relaxes the muscles and stops the production of the lactic acid. Sleep is thus very important and can thus, restore our body’s energy after a period of hard work. The best way to energise and refresh our tired muscles and body is to make it a point to sleep for at least eight hours every day.

431 words | 4 minutes
Readability: Grade 7 (12-13 year old children)
Based on Flesch–Kincaid readability scores

Filed under: 5ws and h
Tags: #muscles, #brains, #sleep

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