Honey, do you mean running outdoors? If your running knee hurts, it is recommended to take a walk outdoors and lengthen the time. This natural way of walking is most suitable for your current knee condition. You can also buy an elliptical machine to exercise at home. This equipment is also a kind of sports equipment that simulates the natural walking of human body. Because the human body usually takes an elliptical trajectory, the name of this equipment is elliptical machine, which is available at various prices and is a good fitness equipment that ordinary families can enjoy! I hope I can help you!