>>1435519am distance runner, carry 1 liter of water, base layer top and bottom, headlamp, sometimes crampons and a rain layer. I've used a variety of fanny packs and a running vest. The fanny packs are either too small, flop around, or chafe. The running vest is nice unless I want to be shirtless, I usually do, in which case it will chafe. Got a belt like in pic related, canteen pouch, 2nd pouch has clothes light and crampons. Haven't gone too far in it yet but it feels nice so far. Will probably still rock the vest for higher, colder runs. Could maybe fit a whole weekend between the two if I bought more pouches.