There is an Xterra I want to do, a month and 4 days from now. I'm not a real good swimmer though. Assuming I am in good enough shape to tackle the biking and running and have pretty good upper body strength... is it possible to train enough in the next month to be able to survive a half mile open water swim? I'm just not real efficient. I've been through lifeguard certification though so I'm not a complete newbie.