WHETHER OR NOT GOD IS HIS GYM BUDDY, Lerner definitely practices what he preaches. He keeps in shape by running or biking, works out in a home gym, and adheres to the Body by God diet. In the time I spent with him, I found Lerner to be disciplined, driven, and focused. I also found him to be motivated by a sincere wish to share his healthy lifestyle with others. If he has a flaw, it may be his all-consuming self-confidence—which at times borders on hubris. Lerner is so convinced of his ability to help fellow Christians that he often passes off his own teachings as God's.

Still, it's safe to say that Dr. Ben will find more followers in 2006 as he rolls out new components of his growing empire. In a move designed to increase his presence in the secular world, Lerner plans to publish a few books that leave words like "God" and "Bible" out of their titles. Generation XL Excel, for example, a kids' self-help book about obesity that Lerner co-wrote with Chicago-based osteopath Joseph Mercola, is due out this spring. Lerner has already been booked as keynote speaker at the 2006 National Parent Teacher Association convention, to be held in Phoenix this June.

Next fall, to serve Lerner's Christian fan base, Thomas Nelson Publishers will release The Maximized Living Bible, an annotated Bible linking various passages to fitness, health, inner peace, and financial well-being. Lerner will continue to build his consulting business and speak at some of the 400 Body by God Extreme Makeover Challenges already on the 2006 calendar, in cities from Colorado Springs to Chicago.

Ultimately, the best measure of Lerner's success may be the long-term fitness of his followers. Two-thirds of the original 300 participants in the Broken Arrow Makeover Challenge stuck with it through the end, Lerner reports. And he believes faith will help them hold on to their healthy habits.

"Body by God was created in a working laboratory of thousands of patients," he says. "I only recommend what people are able to follow. And I teach that motivation alone does not work. Commitment, the mature decision to take care of your body, can only come from inspiration—from something outside of yourself."

Three months after the Arrow Heights contest, I check back with Nigel Allen, the former Mountain Dew addict. Allen proudly reports that he's lost an additional five pounds.

"Without all that weight on my knees, I'm able to jog now, and I can run after my daughters," he says. "In order to be a spiritual leader for my family, I simply have to stay in shape.

"We'll never know if certain things in life work," Allen continues. "If religion is wrong, what are you losing out on—Sundays? It seems to me that chiropractics and religion are investments—and cheap investments at that."

The key, Allen concludes, is believing.