It's a fact-Pilates is among the fastest-growing activities in the United States, boasting more than 8.6 million practitioners in gyms, community centers, and studios across the nation according to CNBC.

But what exactly is Pilates? How can it help you transform not only your body but also your mind and spirit? And how did Pilates "elders"-the first-generation instructors who trained directly with Joseph Pilates-carry on the pioneering work of this German-born body builder, wrestler, gymnast, and boxer, who developed the Pilates system nearly a century ago?

"Pilates helps build flexibility, muscle strength, and endurance in the legs, abdominals, arms, hips, and back, but it is not just a workout," says Amanda Rhine, owner of the Discover Happy studio on Water Street in Decorah. "It's a system by which to live-a system that changes the way you feel about yourself, your life, and the world that surrounds you."

To help community members better understand this unique physical-fitness system, Rhine is launching a five-week series of documentaries, each focusing on a different Pilates "elder" (Eve Gentry, Carola Trier, Ron Fletcher, Kathy Grant, and Romana Kryanwoska). Provided by pilatesanytime.com, the documentaries will be screened at Discover Happy at 10:30 a.m. on successive Sundays beginning January 12. Attendance is free of charge (though advance registration is required at www.discoverhappydecorah.com) and includes an optional mat class influenced by each elder's technique following the screening.

"No experience with Pilates is necessary," says Rhine. "I'm doing this to help educate the community about the history and evolution of Pilates...what has kept Pilates moving, and why has it thrived as a staple form of exercise and way of life?" The series precedes the planned screening of A Movement of Movement-an acclaimed documentary that explores the world of Pilates-at the 2014 Oneota Film Festival, which begins February 28.

"I hope that everyone who walks through the door to watch this documentary series, whether they have taken a Pilates class before or not, understands that Pilates is intended for and can benefit everyone," says Rhine. "Beyond that, the history of Pilates is pretty fascinating."

It was while working as a social worker in Decorah a few years ago that Rhine was given an opportunity to teach at a local Pilates studio. "I immediately fell in love with how Pilates made me feel more alive while increasing body awareness and confidence," she says. "And I could see how it transformed others as well." Inspired, she went on to complete a yearlong Pilates- instructor certification program through the Physicalmind Institute as well as wellness-coach training through Wellcoaches. In November 2011 she opened the doors to Discover Happy, which promotes a collaborative approach to physical and emotional health.

Today, more than two years later, the studio offers a full range of classes, including mat, demi-bar, stick, adaptive response, prenatal and postnatal, and stretching. (Kids Pilates classes, sponsored, in part, by the Oneota Community Food Co-op, emphasize body awareness and healthy eating habits.)

"It has been an interesting journey," says Rhine. "I see more and more people wanting to put their lives into perspective, and Pilates can definitely help. I really hope people will attend this documentary series to better understand why."