Your braids look great! I know what kind of prob you're having because I experience the same thing when I get cornrows and engage in intense physical activity like working out. When you have braids and then sweat profusely, it tends to loosen up the braids faster than normal. I haven't found a real solution to the hairs that seem to seep out the braids, but I have found that tying my hair down with a scarf before engaging in an activity that makes me sweat helps to keep the loose hairs in place.