Why do i not have pain in my knee when swimming but always during other sporting activities?

Nonimpact: Swimming is non-impact, meaning there is very little load or force going through the knee joint and surrounding structures while in the water. Elliptical would be low-impact, walking medium-impact and jogging/running high-impact. If you haven't already, it may be time to see a sports doc to obtain help in overcoming this pain.

Non-weight bearing.: If you have knee problems, you are not weight bearing on your knees when you swim. Other less weight bearing activities include biking, aqua aerobics, etc. Activities to avoid: running, tennis, softbal, etc.