Life is all about adjusting to situations. As we season, fitness can be adjusted! So you can't run anymore on those aching knees, SO WHAT yes I said it! It has been a mental struggle not to take off on those long runs...but I have come to terms SO WHAT! ADJUST ADAPT KEEP MOVING! I love to work my heart so I spin hard, box, battle ropes, kettlebells etc and yes sometimes I JOG!