Mid-South Mud Run, Millington

Most people would be intimidated to run an obstacle course against US Navy sailors. Luckily, the Mid-South Mud Run is (mostly) for fun, a 5K event that raises funds for the Navy-Marines Corps Relief Society. The course leads soldiers and civilians alike across horse pastures and down the lakefront trails surrounding Navy Lake. As they're running, participants will encounter 13 distinct and messy obstacles—mud pits, tunnel crawls, a slip 'n' slide—each designed to challenge competitors but not hinder them.

But don't worry if you're not quite in Navy shape—those who can't complete an obstacle or suddenly remember they have a meeting with the president are welcome to move on, and there are staffers out on the course to help you complete the obstacles. There are awards for the fastest times, but the event is more in the spirit of having a good, muddy time and raising money for a good cause.