Cross Training for the Marathon

I’m actually also training for two sprint triathlons that will take place before the marathon. I figure some good cross training should help me get in shape and avoid injury. They’re 500 M swim/12 mile bike/3.1 mile run. The first triathlon is June 7, and that’s the iffiest one- I haven’t swum laps in forever (and I'm not a real strong swimmer to begin with), and it’s now less than a month away. I’m going to have to work hard and pray for the best. The biking and the running I should do ok on- I’m training with DD in our bike trailer and our jogging stroller. Come race day, I’ll have a lot less resistance/weight to carry around, and that should help my endurance and speed. The next triathlon is in August (there’s actually one in July, too, but I’ll be out of town then), and I should do a lot better in that one. Then the marathon is the middle of September. After that, there’s some 5K and 10K trail runs and road races I plan on doing. Once winter comes, though, we’ll have to see if I can keep training. I need to: I can’t go November to April without exercising- it’s just not good for me physically or mentally. I may have to get some exercise equipment and workout indoors. I’ve been wanting a Bowflex Treadclimber, but they're on the expensive side. Hopefully when nasty weather comes again I'll find one on craigslist.