"Hey van #2 I shaved my legs. You're welcome."

That Thursday morning Twitter post from @mkemom exemplifies the intimacy of the Ragnar Relay brought about more and more from anonymity.

Via Twitter, dailymile, Facebook and other social media vehicles, strangers are connecting for one of life's most up-close, partially clothed experiences: the road trip.

Kimberly Laczniak, a 42-year-old working mom from Menomonee Falls, recognized the craziness of the endeavor last year, when she signed on to join a team for the Ragnar Relay Chicago, a 200-mile race from Madison to the Windy City.

With a few clicks of the keyboard, she put herself in a van for more than 30 hours, with five people she had never met.

"I met the first teammate when she picked me up to drive me to Madison on Thursday night. I wasn't nervous in the sense of what if I don't like them. I was more nervous, we're driving to Madison, what are we going to talk about?

"I'm so afraid of the unknown, and with Ragnar, there's a lot of unknown," Laczniak said.

As Laczniak understated, the logistics of a 200-mile relay are a mystery for many runners. With teams now forming via tweets and Facebook posts, the teammates themselves are also unknowns.

Meghan Reynolds, the social media and marketing manager for Ragnar, estimates that roughly 30 percent of the 70,000 relay runners across the country "just jump in with random teams." That's a remarkable and rapid change in less than a decade.

Based off the much-publicized Hood to Coast, now in its 31st year, the Ragnar Relays have teams of six or 12 running roughly 200 miles, creating the overnight road trips that many endured on spring break or family outings, with or without the exertion and the sweat.

While one team member runs, the others drive to the next hand-off point. Twelve-member teams are split into two vehicles.

In the early years, Ragnar teams formed largely through running clubs or groups, longtime training partners joining for a combined effort.

Today, the explosion in relatively anonymous social media has been a force behind the growth of Ragnar, from one race in 2004 to 15 in 2012.

Social media fueled Ragnar by making it easier for people to fill out their team, augmenting the "runners wanted" postings on the relay web site.

"What I hear from people is 'I don't know 11 people,'" Reynolds said. "I suggest they get two or four friends, then jump on a team, so that at 3 or 4 in the morning you have someone to complain or relate to."

Even compared to that approach, Laczniak's team was special.

None of the 11 women who eventually gathered in Madison the Thursday night before the start in Olin Turville Park had ever met in person. They would be stuck together, all the way to the finish line in Chicago's Lincoln Park-Montrose Beach.

Like Laczniak, Ginesa Schleuse signed on in response to a Twitter post from a friend desperately seeking to replace women who had dropped out in the weeks leading up to Ragnar.

With a snap decision, Schleuse threw in with women from Alabama, Missouri, California, Illinois, Ohio and Wisconsin. It was a matter of timing, as much as destiny.

"It was the first time I had used twitter in this manner," said Schleuse, a physical therapist from St. Francis. "My husband was a lot more concerned than myself. There's no way to verify what you say, who you are. You don't have an understanding of what that person is like.

"You have the extra dynamic in there of females all getting along, that type of thing."

Even among long-time friends, the Ragnar experience can be trying. Snippiness borne of physical exhaustion and sleep-deprivation is common in the pre-dawn hours.

It gets quiet in the van. Answers become frustrated mutterings. There may be screaming.

"You put six people in the van together for 30-plus hours, how do you know personalities aren't going to conflict," said Marty Burian, a Milwaukee Web developer, who raced last year with a combination of friends and new acquaintances. "Everybody gets it that you can either have a good time or have a bad time, 'so let's have a good time.'"

Despite a few obstacles and missteps, Laczniak and her teammates fully embraced that philosophy. Strangers became close, and not just physically.

"Ginesa and I met that Thursday night and since then we've been practically inseparable, and the same thing goes for a couple other people on the team," Laczniak said. "I adore everybody in my van.

"We never fought. We had fun. We laughed. I don't know if everybody has that experience, and we may not have always agreed on things, but at the end of the race, we all got along."

Reynolds envisions more growth in the social media connections that bring Ragnar runners together, and muses that the operation should bill itself as an online dating service. Dozens of runners have met on the relays and each race seems to include an engagement.

"It's another way to meet people who have a similar interest," said Schleuse. "I wouldn't have found Kim if not for this team. Our kids don't go to the same school. We don't live in the same town."

Now they commiserate about motherhood, exchange updates on their training and race together. They will run together again, starting early Friday morning, in the 2012 Ragnar Chicago.

Their lasting friendship was forged on the way to the finish line, as a team appropriately named: "Online Relationship."