Step away from the holiday cookie tray and test what you're made of at one of Chicago's ninja gyms.
Hot Ground Gym
Hot Ground Gym

How hard is it actually to leap, swing and climb through the obstacle courses on American Ninja Warrior? Twenty bucks lets you find out when you drop into a two-hour adult ninja warrior training class in Chicago Ninja Academy, owned by four-time contestant Nate Aye (aka Coach Nate).

You'll start with safety instructions, followed by warm-ups and a skill evaluation. Then you'll hop across the angled quintuple steps and do some basic hanging and climbing. Crushing it so far? Instructors will up the pace and difficulty.

You might even spot an American Ninja Warrior contestant practicing on the Jumping Spider wall (spring off a trampoline and perch between two walls) or climbing the Double Salmon Ladder. Last year, 10 people from the gym made it onto the show.

Hot Ground Gym
Hot Ground Gym. Photo courtesy of Hot Ground Gym.

Kids get their shot at ninja-dom at Hot Ground Gym in Northbrook, where the owners-military veterans and parents-teach boot-camp-style classes on kid-size equipment, emphasizing teamwork and character. High fives fly after each obstacle.

"The hard part isn't doing the stunts-it's doing them one after the other," says 11-year-old J.J., chugging water after a 45-minute class. "I'm tired, but it was awesome."

Different levels of membership are available, and five-class passes are $150.