Yes I bring one bottle per 5 miles so I had a total of two for the 10k run...one with water and one with gatorade. I've suffered the effects of dehydration during the hot Nashville marathon in 2011. I broke my 4 hr goal by 11 minutes still but I had to sit down going up the last hill because I started seeing spots and nearly blacked out 0.2 miles from the finish. But I finished.