Triathlons and Marathon training don't really go hand in hand.

Let's see, since June I have done a duathlon, 2 triathlons, and have been maintining my mileage for the GR Marathon. It was tough and confusing at times. But I think I am in pretty good shape right now to do just about anything. . .even wear my bikini! However, I will have to say that cross-training is only good to a point. Substituting a triathlon race is NOT a replacement for long runs 10 miles and up. At some point, the body just needs those long runs and a two hour workout of swim, bike, run doesn't cut it for a 13 mile run! I ran 13 miles last weekend after alternating tris and long runs for about a month. It wasn't the best long run I ever had except that it was flat and gorgeous scenery. I felt like my body hadn't done that in a while and it was like, hello---what are you doing??!! So, what I am learning is cross training is good to a point and running is still by far the best overall fitness one can get. It is good to use the others in recovery from an injury or to maintain fitness during off seasons, but it is NOT a replacement in times of tough training, i.e. a marathon. So, although I really, really, really want to do the last triathlon for this season in our area next month, I think I will just need to stick to the plan of an 18 miler that day.