By Madelyn Stone, News Staff

Partial nudity, shopping carts and zombies may not have much in common, but this year each is putting a new spin on adventurous exercise for Bostonians.

The shopping carts come in at the Boston Urban Iditarod, which gave the streets of Cambridge a form of the Alaskan dog-sled competition for its second annual race on March 3. Instead of dogs drawing sleds, teams of four to six people pull grocery carts, each group decked out in their choice of themed costumes.

Inspired by the Urban Iditarod in Chicago, Kevin Doran, who owns a heating and air conditioning company out of Charlestown, and Tim Jones, who operates an internet advertising company from Medford, co-created the Boston version and included a food drive for a local pantry.

“I think for Tim and I, we’ve always been kind of adventurous, if you will,” Doran said. “We had competed in several other events in and around Boston, different types of adventure races or scavenger hunts or 5k road races, triathalons, all those things. We kind of wanted something more, something that had a little bit more craziness to it, or more dynamic of a race.”

The iditarod’s success – the number of teams jumped from 17 in 2011 to 67 this year – reflects a general trend in inventive foot races.

Also exploding in popularity is “Run for Your Lives,” a 5K adventure race that sets up an apocalyptic life or un-death situation for runners. Chased over mud, around nets and through pools of “blood,” the humans in the race dash to escape the clutches of fully costumed zombies. Combining an obstacle course with capture-the-flag style competition – runners must keep at least one of three flags on their belt to “survive” – Run for Your Lives is the creation of Maryland residents Derrick Smith and Ryan Hogan.

“Our first event, in Maryland, was in October of 2011,” Smith said. “We thought it was going to be a small event and it turned into over 12,000 people showed up. So that was enough for us to figure out that we wanted to go ahead and take it on the road.”

Smith said the Run for Your Lives team has 13 races lined up this year, the first of which took place in Atlanta earlier this month. The May 5 zombie run in Amesbury, Mass., has received such an enthusiastic response that the creators extended the festivities to May 6.

“In a little over a year we’ve accumulated over 160,000 Facebook fans,” Smith said. “We definitely got a little lucky and found something that people definitely enjoy.”

Combining elements of drama and fantasy with an active community event, Run for Your Lives has attracted a multifaceted crowd. Smith said they receive plenty of feedback from regular 5K runners, but also draw the interest of the less athletic.

“As we travel across the country and we go to each different location, what we keep finding and what we receive a lot is that a lot of Facebook posts say ‘This is my first 5K,’ or ‘Finally I have an excuse to run,’” he said. “And I think we took those indoor kids – the video game enthusiasts, the comic book readers, that sort of thing – and we tapped into something that they enjoy and we gave them a different outlet to enjoy that hobby of zombies or horror or fantasy.”

Run for Your Lives registration for zombies has already reached capacity, but racer and volunteer sign-ups are open through April 13.

Amy Steele, a freshman health science major, participated in Northeastern’s own underwear run last October. Despite the fact she was on crutches at the time, Steele said she joined in the flesh-happy fun because the unorthodox race was an opportunity her friends and her could not miss.

“It’s just such a fun way to stay active like with everyone else, like acting goofy and stuff,” she said.

Creative races abound in the area, with the December SSRun (formerly the Santa Speedo Run) bringing participants together in little more than their holiday-themed skivvies. Earlier this month, the Pace to a Pint race encouraged runners, many decked out in St. Patrick’s Day attire, to the finish line with the promise of free beer. Worcester’s Big Man Run in June promises similar rewards, offering its racers – who must weigh more than 190 pounds – stops for beer and hot dogs along the four-mile route.

As Jason Shrand, a middler computer science and mathematics major, said of his underwear run experience, the creative races offer a very different outlook on running.

“It was really just a fun way to bond with friends,” Shrand said. “Just a way to be nuts, you know?”