Step 1: Mild fatigue In this initial stage, we may only feel “mild fatigue”, when the amount of inhaled oxygen is reduced, oxygen concentration and blood glucose levels in the blood drop, so the body will send signals, such as frequent yawning to increase the amount of oxygen intake and so on. Step 2: Feeling sluggish At the second stage, the body will feel a heavy burden, muscle weakness, oxygen concentration and blood sugar levels in the blood continue to drop, resulting in muscle or local tissues of internal organs into the dilemma of oxygen and nutrient deficiency, there will be weakness, muddled feeling. Step 3: Emotionally affected At the third stage, the body’s physical sensations will continue to have an impact on the psyche, and the whole body will feel exhausted, and the condition of reduced oxygen and nutrient deficiencies in muscles or internal organs will become more serious, and it will have entered a stage where even light exercise cannot restore physical strength. Emotions may seem agitated and irritable; skin color is dull, and even a small rash grows on the face; stiffness in the neck, shoulders, back and waist becomes more and more serious; it is difficult to sleep, easy to fall off the pillow, and back pain when lying in bed; snoring loudly in bed, or teeth grinding phenomenon. Step 4: Internal variation At the fourth step, the body begins to produce obvious internal variation, and the body is already sick at this stage. The changes in the body include pain in the shoulders, back and waist, accompanied by symptoms such as acne, mouth ulcers, periodontal disease, gastritis, constipation and loss of appetite, and a variety of other ailments continue to appear. These are still common in the physical, and in the psychological, even mild depression will appear. Step 5: Cancer Formation If the first four stages of fatigue are not taken seriously and allowed to develop, major diseases will haunt you from time to time in middle age, such as cervical spondylosis, stomach disease, coronary heart disease, etc., and even cancer will quietly invade you. Once you step into this stage, it will take a few months for the lighter ones and a few years of recuperation for the heavier ones to recover. Rest and exercise are the keys to eliminate fatigue. For example, people who mostly stand when working should sit or lie down when resting; people who always work at a desk should stand up when resting and raise their arms to loosen their shoulder muscles. In addition, in addition to adhere to the daily exercise, but also targeted exercise, where to feel stiff, cold, focus on exercise where.