I haven't warmed up for two or three kilometers, so I can run every day. Of course, it depends on your running speed and the purpose of training. If 2-3 kilometers is too little for your exercise, the correct amount is about 10 kilometers each time, 2-3 times a week, and the speed should be just right. Don't use force (slow down as soon as you gasp). Physical endurance is far more than 2-3 kilometers per day, and it is no problem to run 5- 10 kilometers per day. According to my own experience and the opinions of some runners (all amateurs), it is generally believed that 10 km is the best distance for exercise. If it exceeds 15 km, it will do harm to the body, and it is easy to get injured in legs and feet, fatigue or catch a cold.