As with anything physical that gains a fast following, mud runs are attracting people that normally wouldn't race with promises of a great workout and even more fun. The idea is to run for miles through sticky mud, navigating obstacles along the way. While mud runs are a great way to get a workout and bond with friends, for those new to racing, they present unique risks to be aware of.

Mud runs are typically 3K to 5K in length. Runners, sometimes clad in crazy costumes, run the race while encountering obstacles like ropes courses or monkey bars over mud pits. Most participants end the race covered in dirt, laughing and exhausted, but for some, they emerge injured or worse.

Rocks, tree stumps and roots hidden from view by mud can cause twisted and broken ankles and wrists. Slips and falls are commonplace and participants can easily get tripped up or stepped on in the melee. Some runners suffer scraped knees and elbows, and mud and pond water mixed with others' sweat is a breeding ground for bacteria.

Just this past April, a Dallas man drowned during The Original Mud Run. An unregistered runner in another race is suing organizers for a broken neck he suffered diving into a mud pit.

There are risks with any physical activity. Sports are fraught with broken bones and torn muscles, and for some, the risks are what make mud runs fun. You don't have to let the what-ifs scare you; just know what to look for and take some precautions.

Do your homework. Make sure your mud run is hosted by a reputable organization and don't run without fully reading the waiver you're signing.

Check out the terrain ahead of time. Walk through the course before the race so you know what to expect and can plan accordingly.

Be honest with yourself. If you aren't the strongest swimmer, stick to the perimeter to avoid getting caught up in the crowd. If your upper body strength is lacking, consider skipping the monkey bars. You know your own limits, so don't let your pride get you hurt.

Finally, take your time. These races are more about the experience than coming in first. Don't be afraid to drop back with your group of pals and let the others fight it out while you relax a little and have fun.

Risk is often what makes athletes competitive. Without risk, there would be no reward. Just make sure you know all the risks — before you decide to get down and dirty.

Kelly Turner: kellyturnerfitness@gmail.com; Turner is an ACE (American Council on Exercise) certified-personal trainer and fitness writer. www.KellyTurnerFitness.com; on twitter @KellyTurnerFit.