How long will it take to recover from a radical hysterectomy? I need to start running ASAP after surgery.?

My third biopsy is Tuesday to see if lymph nodes will be taken out as well. I am training for a marathon, and am worried my training will be majorly effected. I know the surgery is most important, but I am hoping to start running as soon as 3 weeks after surgery. I can ask Dr., but can't wait to find out. Anyone have advise for quicker recovery?