四级冲刺练习阅读（37）

　　Three Kinds of Fatigue

　　Fatigue is one of the most common complaints brought to doctors, friends, and relatives. Youd think in this era of labor-saving devices and convenient transportation that few people would have reason to be so tired. But probably more people complain of fatigue today than in the days when hay was baled by hand and laundry scrubbed on a washboard.

　　The causes of modern-day fatigue are diverse and only rarely related to excessive physical exertion. The relatively few people who do heavy labor all day long almost never complain about being tired, perhaps because they expect to be. Today, physicians report, tiredness is more likely a consequence of under-exertion than of wearing yourself down with over-activity. In fact, increased physical activity is often prescribed as a cure for lowering energy.

　　Physical. This is the well-known result of overworking your muscles to the point where metabolic waste products carbon dioxide and lactic acid accumulate in our blood and reduce your strength. Your muscles cant continue to work efficiently in a bath of these chemicals. Physical fatigue is usually a pleasant tiredness, such as that which you might experience after playing a hard set of tennis, chopping wood, or climbing a mountain. The cure is simple and fast: You rest, giving your body a chance to get rid of accumulated wastes and restore muscle fuel.

　　Pathological . Here fatigue is a warning sign or consequence of some underlying physical disorder, perhaps the common cold or flu or something more serious like diabetes or cancer. Usually other symptoms besides fatigue are present that suggest the true cause.

　　Even after an illness has passed, youre likely to feel dragged out for a week or more. Take your fatigue as a signal to go slow while your body has a chance to recover fully even if all you had was a cold. Pushing yourself to resume full activity too soon could lead to a relapse and almost certainly will prolong our period of fatigue.

　　Even though illness is not frequent cause of prolonged fatigue, its very important that it not be overlooked. Therefore, anyone who feels drained of energy for weeks on end should have a thorough physical check-up. But even if nothing shows up as a result of the various medical tests, that doesnt mean theres nothing wrong with you.

　　Psychological. Emotional problems and conflicts, especially depression and anxiety, are by far the most common causes of prolonged fatigue. Fatigue may represent a defence mechanism that prevents you from having to face the true cause of your depression, such as the fact that you hate your job. It is also your bodys safety mechanism for expressing repressed emotional conflicts, such as feeling trapped in an ungrateful role or an unhappy marriage. When such feelings are not expressed openly, they often come out as physical symptoms, with fatigue as one of the most common manifestations. Many people who are extremely fatigued dont even know theyre depressed, Dr. Bulette says. Theyre so busy distracting themselves or just worrying about being tired that they dont recognize their depression.

　　There is a great deal you can do on your own to deal with both severe prolonged fatigue and those periodic washed-out feelings. Vitamins and tranquilizers are almost never the right answer, sleeping pills and alcohol are counterproductive, and caffeine is at best a temporary solution that can backfire with abuse and cause life-disrupting symptoms of anxiety. Instead, you might try: Diet

　　If you eat a small breakfast or none at all, youre likely to experience mid-morning fatigue, the result of a drop in blood sugar, which your body and brain depend on for energy. For peak energy in the morning, be sure to eat a proper breakfast, low in sugar and fairly high in protein, which will provide a steady supply of blood sugar throughout the morning. Coffee and a doughnut are almost worse than nothing, providing a brief boost and then letting you down with a thud. Exercise