During exercise, muscle fatigue usually occurs in the following three different situations. Muscles can't produce enough strength to meet the needs of exercise. The high level of ATP demand prevents the complete oxidation of glucose and leads to the accumulation of lactic acid. The energy reserve in the muscle has been exhausted.
In short-term high-intensity anaerobic exercise, part of the reason for fatigue is the accumulation of lactic acid in the muscles involved in exercise (leading to the decrease of pH value). Continuous high-intensity exercise quickly exhausts glycogen in the muscles involved in exercise. The decrease of intercellular glucose metabolism substrate and the limitation of blood glucose acquisition rate make muscles tired rapidly, and the ability of anaerobic system to maintain ATP biosynthesis is also declining. With the increasing contribution of aerobic energy supply to the ATP required for overall exercise, muscle contraction can continue at a lower intensity.
Exercise fatigue is a common symptom in exercise, which usually leads to decreased excitability, depression, listlessness, muscle weakness and so on. If it is found in time, it can be alleviated as long as it is properly relaxed, but it will bring serious consequences if it is not found in time.
There are two ways to test fatigue, one in the morning and the other in the evening, to find out the difference in values. If it has recovered the next morning, it means that muscle fatigue is normal; First, measure muscle strength several times before exercise and calculate the average. After exercise, measure strength in the same way. If the average muscle strength is lower than the pre-exercise level, or the strength test value drops several times in a row, it can be considered as muscle fatigue. Arm strength test: the subjects hang their arms shoulder-width on the horizontal bar with both hands, then bend their elbows and pull them up, with an interval of about 2-3 seconds, and record the completion times. Test one group before and after exercise. If the number of times after exercise is less than that before exercise, it can be regarded as fatigue.
The most important principle to prevent muscle strain in life is to avoid muscle overuse. If you have to work at your desk for several hours every day, set yourself a small alarm clock, get up for an hour and do the opposite exercise. In addition, doing housework or other labor is the same. Don't do the same thing for long. You can clean different areas every day. Things are done alternately, so that different muscles have a short rest and avoid muscle fatigue.