M.P.
My first thought is to ask you why you are having this done in light of the importance of competing in the upcoming 1/2 marathon. How much time will elapse between the surgery and the 1/2 marathon.
If the prolapsed uterus is causing pain I do understand wanting the hysterectomy but I strongly recommend that you discuss the possibility of safely running the 1/2 marathon with your doctor.
I've had 3 abdominal surgeries because of abdominal pain. During the first surgery the doctor discovered that I had endometriosis as well as a prolapsed uterus. They removed as much endometrium as possible. This involves removing all of the intestines, cleaning them, and then returning them to the abdomen. This caused massive amounts of scar tissue for me which has resulted in my being unable to run, jog, or jump for longer than a few minutes without having pain. I don't think that they yet have a way of determining endometriosis without exploratory surgery. If you're having surgery because of pain, are you reasonably sure that the surgery will remove the cause of pain? If they discover endometriosis (it's my understanding that endometriosis can only be accurately diagnosed with surgery) will you still be able to run?
After giving birth to 4 children my mother had a prolapsed uterus and bladder and had no pain. She used a pessary to help with urine leakage. She eventually had a vaginal hysterectomy and bladder placement correction and was still incontinent.
Perhaps you have a reason other than pain or incontinence for your hysterectomy. Whatever the reason, I would weigh the possible results of surgery with the importance of running this 1/2 marathon. Perhaps surgery would be better put off until after the 1/2 marathon.
I can tell you from experience that it is important to not lift for the time that they tell you not to lift. I thought it was closer to 4-6 weeks. Lifting more than the 2-3 lbs. (I'm not sure this amt. is accurate) uses your abdominal muscles, the same muscles that keep everything in place in your abdomen. By lifting weights, whether it's a gallon of milk or weights designed for sports, you could be allowing your organs to be pulled out of place, especially those organs that are vulnerable because their connection to your body is still weak. You can undo the surgery to lift your bladder. Running, jogging, jumping also puts strain on those new connections.
After I was in an auto accident several weeks after my first surgery an exam showed that my uterus was once more prolapsed. This could have been caused by the accident or it could have happened naturally. How vulnerable will your bladder be to reversal after the surgery? This is probably the most important question for you to have answered by your doctor.
My body made more internal scars than some people. Although I've had several external causes for scar tissue, including the abdominal surgery scars I have no pervasive external scars as I do internally. Every body is different. Asking this question is shows that you are concerned about long term effects. I'm glad. Please talk with your doctor, too.
I want to add that recovery from surgery with general anesthesia takes time. You will have less energy for several weeks. You will no doubt recover faster than we average people who don't train but you'll want to take into consideration the amount of energy you have along with what activities you have that are not optional.