I've had both acl's replaced so my knees kill whenever i try any sort of cardio. the swelling drains into my ankles and hurts for days. help!?

See orthopedist: Fluid build up after acl knee surgery could be due to many reasons such as: 1) scar tissue rubbing the knee 2) new tear in meniscus 3) new or worsening cartilage wear/damage (early arthritis ?) 4) reaction to cadaver graft if used for acl reconstruction. 5) lack of rehab. 6) activity/impact loading mismatch: your acl knees and associated injuries cannot handle your activity expectations.