After squatting thigh muscle soreness first to exclude soft tissue damage, muscle soreness caused by muscle microstructure damage or lactic acid buildup, can be gradually relieved after 1-3 days, soft tissue damage caused by muscle soreness need to be timely treatment. The normal person will have muscle soreness within 12 hours to 2 days after squatting, and most patients have delayed onset muscle soreness, which is caused by anaerobic respiration of the muscles during exercise to produce more lactic acid buildup, or due to damage to the microstructure of the muscles. The accumulated lactic acid will be metabolized gradually through the lactic acid cycle, and the damaged microscopic muscle structure will be repaired gradually, this process usually takes 1-3 days, if the muscle soreness is caused by other factors, further treatment in hospital may be required. You can apply cold compresses to promote the repair of muscle microstructure and metabolism of lactic acid after exercise, and try not to apply hot compresses, otherwise it will aggravate muscle soreness.