I recently purchased one of these for a friend (in pink) and one for me as well (in blue) because we wanted to have a convenient method of bringing water with us as we ran trails in preparation for a few summer 5K and 10K trail races. These packs have worked perfectly, and now we never leave home without them. They carry just enough water so you don't have to stop at water stations along the race routes. Plus, the strap across the chest keeps the pack in place while you are running so it's not flopping all over the place, which was my main concern when purchasing a CamelBak for running. The women's fit is also quite nice as the shoulder straps are very comfortable and fit just right. I would definitely recommend these packs for running, and they would also be useful for outdoorsy adventurers who enjoy mountain biking, road biking, kayaking, and hiking. With this summer being so extremely hot, it's nice to have a convenient method of carrying a bunch of icy cold water! The pockets are perfect for holding keys, cell phones (even the larger phones), a camera. I would buy another one of these hydration packs in a heartbeat!