I very much prefer the front pocket vest to the backpack reservoir when running, it sloshes around a lot less. I also put about 1/8 tsp salt in each of the 500ml flasks for a little bit of electrolytes to prevent cramping on long runs.
You shouldn't have any sloshing if you suck all the air out. I'm mentioning this because to my surprise, a lot of people, even experienced runners do not realize that iscan option, and were used to running with their water sloshing around as they run. :)
It feels like the front pockets on the vest are securing the two soft flasks pretty well. There doesn't seem to be any swinging at all.
I very much prefer the front pocket vest to the backpack reservoir when running, it sloshes around a lot less. I also put about 1/8 tsp salt in each of the 500ml flasks for a little bit of electrolytes to prevent cramping on long runs.
You shouldn't have any sloshing if you suck all the air out. I'm mentioning this because to my surprise, a lot of people, even experienced runners do not realize that iscan option, and were used to running with their water sloshing around as they run. :)