FORT LEWIS — Three of Spc. Jeffrey Sigerson’s fingers are curled, the result of his right hand being crushed in the door of a Humvee during an ambush in Iraq last year while he was on a ­convoy-security mission.

On top of that, his entire torso twitches frequently after an accident in basic training left him with dislocated vertebrae and damaged nerves.

But as Sigerson rowed himself around American Lake on Thursday, the Fort Lewis soldier found peace on the choppy waters.

“I thought it would be a lot harder to do,” the 40-year-old Tacoma resident said after 30 minutes on the lake. “But I found out that it’s something I can do. It was relaxing. It’s freedom on the water.”

Sigerson and 14 others from Fort Lewis’ Warrior Transition Battalion, a unit for soldiers with complex or long-term health concerns, rowed and played sitting volleyball during a camp run by the U.S. Paralympic Team.

Another 15 veterans or active-duty military personnel from other bases also participated in the camp, which began May 5 and concluded May 8.

Sports are growing in popularity as a way to help wounded and injured service members; proponents say they encourage physical activity after a traumatic event and provide a sense of calm. One local nonprofit, the Wounded Warrior Adaptive Golf Project, helps link disabled soldiers and veterans with mentors on the links.

Many of the participants in the rowing session May 7 rode in adaptive double scull boats, in which the rower sits higher in the boat and is buckled into the seat. Several had lost their legs or some use of them, and the modifications allowed them to row using only the power of their upper body. Sculls usually have a sliding seat, putting an emphasis on leg power.

Many soldiers and veterans were rowing for the first time. Cpl. Jorgen Quezadaaros, the son of a Navy sailor, had rowed as a child but was in the water again for the first time in years.

The 30-year-old New York native has spent 10 months in the Warrior Transition Battalion. He is recovering from a back injury and a traumatic brain injury, the result of a roadside bomb strike in November 2007 that threw him from the hatch of a Stryker vehicle during a deployment with the 4th Brigade, 2nd Infantry Division.

“They should do more of this for the soldiers, for all the soldiers,” said Quezadaaros, who normally teaches Arabic at Fort Lewis’ language school on Thursday mornings. “This shows you that you can do this, even if you’re injured.”

Roger Neppl, the director of military programs in the U.S. Olympic Committee’s Paralympic Division, said the camps receive funding from the Department of Defense as part of a larger effort to rehabilitate injured service members.

Paralympics officials will lead or provide support to nine camps at military installations this year, with an average of 40 to 50 participants at each event. The U.S. Olympic Committee plans to have some level of activity in 15 of the Army’s 35 warrior transition units by the end of 2009.

If an athlete excels at one of the camps, there’s an opportunity to train and try out for a national team. But Neppl cautions against seeing the events as a series of on-post farm systems.

“The primary goal is to let them get back in the game of life,” he said. “I’d be perfectly happy if someone becomes well enough to take a Sunday bike ride with their family.”

One of last week’s participants is already training to make the U.S. rowing team at the 2012 London Paralympic games.

Sgt. Robert Brown’s right leg is amputated below his knee, the result of sniper fire during an ambush in September 2006 in Ramadi, Iraq, during a combat patrol with the 1st Armored Division. The 25-year-old is recovering at Walter Reed Army Medical Center in Washington, D.C.

Brown is traveling around the country this year to attend several Paralympics camps, where he helps other soldiers with little or no experience in rowing. He hopes to stay in the Army for a few more years and qualify for the World Class Athlete program, which allows soldiers to train for national and international competitions.

Sports “have really given me something to focus on lately,” Brown said. “It’s definitely been a good experience.”