| DO YOU feel tired most of the time? Dr. Frank S. | | | | chemical changes are of critical significance in |
| Caprio, a prominent psychiatrist, writes: "Nervous | | | | normal fatigue, except possibly in very heavy |
| fatigue is so common today that it has been | | | | muscular work. For normal kinds of sedentary |
| referred to as the Great American Disease. Most | | | | work, chemical changes in the muscles play a |
| patients who consult a doctor complain of chronic | | | | minor part." |
| tiredness." | | | | Common experience also runs counter to the |
| So great is the problem of always felling tired that | | | | view that fatigue is due simply to expenditure of |
| some years ago Science Digest observed: "Every | | | | energy and chemical changes in the muscles. |
| year doctors prescribe at least 3500 tons of | | | | Consider, for example, the worker who feels |
| amphetamine stimulants just to help their patients | | | | fatigue after hours of work, but then his fatigue |
| get through the day." | | | | suddenly leaves him. You probably have had that |
| If you are one of those who are "tired all the | | | | experience. |
| time,' do you know the reason? What causes | | | | Perhaps you can remember being tired after |
| fatigue? | | | | hours of work. But then you were invited to do |
| The diffuculty of answering this question may | | | | something that you really enjoyed, such as play a |
| surprise you. The World Book Encyclopedia notes: | | | | game or go for a hike in the woods with friends. |
| "Doctors do not know exactly what causes | | | | Even though this required perhaps more energy |
| fatigue. They do not know why a person feels | | | | than the work you were doing, almost at once |
| tired after muscular exertion or mental effort." | | | | your tiredness vanished! |
| Yet the answer may seem quite obvious to you. | | | | You probably have had similar experiences that |
| It is commonly thought that when a person | | | | make the question of fatigue baffling. For |
| works, he uses up energy, and waste products, | | | | example, you may have discovered that you are |
| such as lactic acid, accumulate in his blood. As a | | | | less tired when doing work lyou enjoy than when |
| result, he becomes tired. Yet the matter is not all | | | | doing even easier work that you do not enjoy. |
| that simple, although there is certain truth in the | | | | Many persons, in fact, get tired while hardly |
| above view. | | | | exerting themselves at all. Even the thought of |
| That waste materials in the blood apparently are | | | | having to do certain things makes some persons |
| a factor in producing fatigue is shown by the fact | | | | tired! Such true-life experiences causes the journal |
| that injections of blood of a fatigued animal into | | | | today's Education to conclude: " There is |
| one that is rested will produce fatigue in the | | | | something wrong with the common assumption |
| rested animal. Yet The Encyclopedia Americana | | | | about what causes fatigue or even about what |
| comments: | | | | fatigue is." |
| "Under norma conditions . . . the muscle is kept | | | | The book Fatigue and Impairment in Man, after |
| supplied with sufficient nutrient material and the | | | | presenting extensive research on the subject, |
| waste products are reconverted to supply new | | | | explained: "Fatigue . . . bears no consistent relation |
| energy so long as the blood supply of the muscle | | | | to expenditure of physical energy. |
| is intact. It is therefore unlikely that these | | | | |