Amanda Bynes with workout group
Courtesy Miracles Utah Fitness Retreat
01/23/2014 at 06:10 PM EST
For Amanda Bynes
, the road to recovery must be traveled in snowshoes.
Just before starting classes at the Fashion Institute of Design and Merchandising in Orange County, the troubled actress was hard at work getting her body in shape.
Bynes, 27, who left an inpatient mental health treatment facility
in California in early December, arrived at the exclusive Miracles Utah Fitness Retreat
on Jan. 4 for a week of six-hour a day workouts and healthy meals.
"She wanted to focus on her health and getting her body back in shape," owner Austan Torson tells PEOPLE. "Her main goal was to lose 5 lbs. and she did."
Torson said in designing a program the center consulted with Bynes and her family. Bynes has been recovering at her parents' Los Angeles home.
Her mother Lynn remains in indefinite control
over Amanda's well-being after she was forcibly hospitalized
following a period of erratic behavior, including a driveway-burning incident in July.
At the $3,250-a-week Utah center, Bynes joined a group of 15 others for daily cardio and core exercises, healthy meals and lectures on nutrition and health.
"She brought a lot of life to the program," says Torson, adding that the actress got along with the others in her group. "She was really funny, fired up and open to anything."
That included the strenuous day of snowshoeing in the cold. "She led the pack," says Torson. "She was right in the front."