Not just any barn, but a barn with a weight room he built at his home in Michigan. Instead of living in Northern Virginia and fighting traffic every day to get to the Washington Redskins' training facility, the veteran right tackle simply walked out the door and did what he had to do to stay in shape.
"I was home the whole time, and I feel great, too," Jansen said. "If I'm here, it's four or five hours. If I'm home, it's an hour and a half, and I'm done. Then the rest of the time I'm with my daughters and my wife. It's what the offseason should be."
In January, after his worst season as a head coach, Joe Gibbs yielded to veterans who were complaining about burnout from year- round football and put the "voluntary" back into the team's voluntary offseason training program. When players assembled Tuesday for the first practice of the spring, it was the first time that nearly the entire team had been together since saying their goodbyes at the end of the 5-11 season.
"It's good to get away," receiver Santana Moss said. "I go home and I not try to see nothing about football."
The team's three University of Miami stars - Moss, running back Clinton Portis and safety Sean Taylor - went home to Florida. Receiver Brandon Lloyd and cornerback Shawn Springs worked out in Arizona. Defensive end Renaldo Wynn was in Las Vegas. Phillip Daniels, perhaps the biggest proponent of the change, went down to Georgia.
Springs and Taylor must have really enjoyed themselves because they were the two most noteworthy absentees at Tuesday's practice, officially called an organized team activity. Springs has been the subject of trade rumors, and Taylor has repeatedly been dismissive of any offseason work that's not deemed mandatory by the league.
Washington's only mandatory event this offseason will be next month's three-day minicamp.
Portis also has never been thrilled about the idea of spending offseason time in Virginia when he could be in Miami, but he was on hand Tuesday. Portis continues to recuperate following shoulder surgery and said he is being cautious with his rehabilitation.
"I actually think I'm doing more this offseason than I ever did, with my strength and getting back in shape and conditioning and my body," Portis said. "I looked at myself in the mirror the other night and I feel pretty good about how my body looks, so I'm on pace for South Beach. I can walk around with swim trunks on."
Gibbs said he was willing to try anything after finishing 5-11, even changing a routine that had made him so proud in the past. When the Redskins made the playoffs two years ago, the coach attributed it in part to the "best attended offseason in all of sports" - a 97 percent attendance rate starting with workouts in mid-March.
Last year, the attendance rate was about the same, but by November the wear and tear was starting to show. Daniels was the most vocal. He said the offseason program sapped him and made him more injury prone because it was so different from the power-lifting program he always pursued in Atlanta.
Daniels, not wanting to criticize the Redskins any further, tried to take back some of those remarks when he met with reporters Tuesday. Nevertheless, he said he felt good after his offseason at home as he attempts to return from three operations: two ankles and one wrist.
"I feel like I'm getting back to that form, working out every day and doing the things I can to try to help this team win a Super Bowl," Daniels said.
While the players who decided to go away grabbed the headlines, they were actually in the minority. Running back Ladell Betts estimated that 60-75 percent of the roster stayed in the area and worked out at Redskins Park over the past two months.
It's also an open question whether Gibbs' new approach will lead to more victories. The sturdiness of the defensive line and the performance of quarterback Jason Campbell figure to mean more in September than whether Jansen was lifting weights in a barn or at Redskins Park. But on this day, at least, Jansen had the type of smile that could only come with recharged batteries. "I've always been excited to come back in and get ready for football," Jansen said, "but you feel so much more refreshed, a little more excited because I haven't seen the guys and haven't done the football thing in a while. I feel fresh."