Well, most obvious solution would be something like a drinkers helmet: But jokes aside, what is an effective way to carry water when training for a marathon or just casually running long-distance? ...
I carry a lot of water on my bike, when I cycle. A camelback with a 3liter reservoir and 2 bottles of 0.7liters. When running dehydration is not yet an issue, as I run half an hour maximum at the ...