There are three main reasons for the soreness of the calf muscles after getting up from bed: 1. Before going to bed, there is strenuous exercise in the calf area muscles, which can lead to strain and inflammatory accumulation of local muscle overwork. Because the blood circulation is faster during the activity, the metabolites produced can be effectively metabolized, so there is no soreness. The actual fact is that the actual blood circulation will slow down during sleep, and the local metabolites will accumulate and cause soreness and pain. 2, because the calf muscles are not fully relaxed during sleep at night, it will also cause the muscles to be in a tense state to form fatigue. This will consume more electrolytes and energy, which will also lead to the feeling of soreness. The accumulation of local inflammatory metabolites leads to more obvious pain.3. It is due to the condition of cold in the calf during sleep, because the cold causes the muscle to become tense and local inflammatory metabolites to gradually form. The blood circulation slows down and the venous return decreases after the cold, which also causes the accumulation of local inflammatory metabolites and aggravates the soreness.