Runner's knee is improper tracking of the knee usually caused by running on crowned roads. It can also be caused by motion contorl shoes that lock the knees so they are not able to rotate with each stride.
The crowned road causes the, usually higher foot, to turn inward, which affects the tracking of the knee. Over time this causes wear, pain, and can severly injure the knees.
Strengthening exercises do not help. Runner's knee is a tracking issue, not an issue of strength. In fact, strengthening exercises will make the injury worse. Avoid cycling for that reason, as it puts pressure on the injury.
You must avoid the causes, stop running on crowned roads, make sure your shoes allow mobility of your knees and do not force your feet in one direction or another.
Soak your knees in cold water and ice cubes for 3 to 5 minutes at a time, several times a day including before and after running, until they are completely healed. Rubbing with ice cubes is not enough. You need to get on your hands and knees and submerge your knees one at a time in a shallow bucket of ice water. It will take a week or two for the inflammation to reduce to where you can run with no pain, provided you have first removed the cause of the injury.