For my iron training I'm doing much longer runs (and usually on trails where there aren't any water stops). I've been carrying my camelbak (took just a couple runs to get used to it- and it's actually MUCH more comfortable than my old bottle waist pack). I put water in the camelbak, and then I also wear a fuel belt with bottles of gatorade (which I use more sparingly). It also has a place for my gels/sport beans. I must look silly, but I don't care how I look. I'm well fueled and that's all that matters to me.