I’ve come across articles and messages posted on message boards suggesting that running with a hydration belt slows you down.
Personally, when I am running for more than 20 km I bring my fuel belt with 4 8oz bottles.This goes for half-marathons and marathons as well. The reason I choose to carry my fuel belt for these races is that most races offer Gatorade at water stations and I find Gatorade to be too sweet.
I am planning on running my next marathon here in Ottawa in May. I will be trying the same approach of carrying my fuel belt as I try to improve on the 3:22 I ran in October.
I guess it probably all comes down to personal preference and what you are used to. What do you think?