It is best not to run for three days before menstruation, and you can do moderate exercise after three days. Three days before menstruation, just do some simple stretching at home. These light exercises can help blood flow smoothly and relieve stress.

During exercise, you must avoid putting pressure on the abdominal cavity and raising your legs too high. If you feel tired or find a sudden increase or decrease in blood loss, you need to stop exercising immediately.

On the fifth day of menstruation, the body began to recover. At this time, you can start aerobic exercise such as walking and jogging. However, we should avoid some ball games and heavy-duty sports.

Extended data:

Proper exercise during menstruation can regulate the body, but if it is improper, it will bring great harm to the body. Women should avoid strenuous and excessive exercise during menstruation: do not participate in high jump, long jump, 100-meter race, football and other sports during menstruation, and do not do strength exercises such as push-ups and dumbbells to increase abdominal pressure, so as to avoid excessive menstrual bleeding or change the position of the uterus.

References:

Menstruation _ Baidu Encyclopedia