Hi lovetoRN, many things to touch on here. The constipation is a classic symptom of a rectocele (refer to the 2nd post on the forum about taking pelvic organ prolapse out of the closet for POP basics). Were you told what degree your prolapse is? If it is grade 1 or 2, there is a good chance you can correct or at least control it but you will need to take some steps. First of all, you should see a urogynecologist, this is the specialist for POP, they are well versed in treatments for POP as well as surgical procedures to correct it. There are many treatment options available including the ones you mentioned-it is common to use more than one treatment at the same time. Did anyone discuss a pessary with you? (This is an internal structural support device similar to a diaphragm.) If your POP is more advanced like a 3 or 4, it will be more difficult to make it bump back to a lower grade, but you can still opt for treatments rather than surgery-it is truly personal choice.
It is extremely important for you to know that the running is making the rectocele worse (and may have even caused it to get to the degree it is), despite feeling that running strengthens these muscles, what it actually does in cause structural damage to support tissues from the repetetive downward pounding to all the internal organs/tissues. I never recommend women stop running, it is so good for many reasons, what I suggest is getting fitted for a pessary so you have internal structural support while you are running as well as utilize other treatment options for strengthening daily. (Kegels must be done properly and consistently to be effective, there is an article I wrote in the Health Discussions section at the top right of this page that you can access.)
A urogynecologist should be able to fit you properly for a pessary as well as advise you about what other treatment options will help.
It would also be a good idea to do a mirror check of your vagina to see if any tissues are bulging out, if they are you also may have a cystocele.
If you have any difficulty finding a urogynecologist, send me a PM or post to the forum and I can try to guide you. If I don't get right back to you hang in there a bit, I'm heading out of the country soon and am not sure how good my net access will be.
Could I ask how ur doing now?