Hi! So when I was in college, I herniated two discs in my back training for field hockey. After six months of rehab, I was finally able to get back to training to the sport I love. To try and keep from having flare ups with my back I moved to doing pilates, cross training and cut out playing indoor season of field hockey. I also try to do ab workouts at least twice a week. I injured my back back in winter 2007. Two yrs ago I started getting into triathlons and charity 5Ks. Now I would like to try my hand at a half marathon. Does anyone have any suggestions on training or extra back strenghtening exercises that I could do? I'm determined to reach my goal but don't want to be put out of physical activities for another 6 months afterward.
Generally the worse thing for someone with a back injury is sitting or bending. The general guidelines for back injury is to start walking as soon as you can. Run and train for your half marathon, be careful what you do have long training runs, avoid sitting in auto, slouching on couch, or beach chairs. Field hockey is a sport which requires a great amount of bending forward like a someone harvesting strawberries. Train for half marathon, stop playing field hockey.
It also sounds like you have already done more than enough to strengthen your core. 5ks and triathlons are more vigorous than a Half, and can require a lot more raw strength from the core, than a marathon if run competitively. Longer endurance runs require as neutral a running posture as you can possibly muster, so all that strength may be unnecessary for these contests of balance and aerobic endurance.
I am particularly concerned that you mention two ab workouts per week. Overtrained abs are a major contributor to back pain because tight abs pull the rib cage forward. I would back off on those leading up to a long endurance event. The training required alone will be sufficient to acheive the balanced running posture you will need to avoid flare-ups during such a race. Remember that endurance running is a key component of core training for many athletes in other sports. I agree with Damien that in this case, you want to begin to model your musculature for the target sport of endurance running. You have nothing to lose but potential pain.