If you could do only one exercise activity for the rest of your life, what would it be? Emilie Moore, NOBLESVILLE, IND.
Mixed martial arts. It's a great way to stay fit, stay toned, stay lean. I love yoga, but the namaste thing only takes you so far. Every now and again, you just gotta hit something. Not someone something.
You push people to their fullest potential. Who pushed you? Janessa Hurtig, Froid, Mont.
My martial-arts instructor, who worked with me until I was about 21. He changed my life. He demanded that I live up to my potential, and if I didn't, he was like, "I'm not wasting my time. Either meet me halfway or don't bother."
Is obesity about emotional trauma, bad genes or poor habits? Gwen Brandenburg, Reno, Nev.
You can be predisposed genetically, but it's not a sentence. I'm genetically predisposed, but I manage my weight. The root of obesity, though, is usually emotional. The poor habits are a symptom of a deeper emotional issue.
There are numerous video clips of The Biggest Loser in which you smile or laugh when "breaking" a contestant. What are you thinking when you do that? Andrew Williams, Ottawa
I enjoy watching them struggle with something that seems insane. They're just like, "You can't be serious. You must have lost your mind." But I know that they're going to achieve [their goal]. I wouldn't think it was funny if they couldn't do it.
You revealed that you'd had a weight problem as a kid. What are your thoughts on the obesity epidemic among kids today? Michael Charles, Austin, Texas
Obesity in children is growing out of control. A big part of this is economic. Fake foods are more affordable. It's enticing people to eat more because they think they're saving money when they're really just buying heart disease.
I've heard people say they think their body is most comfortable at a certain weight. Is this just an excuse to be lazy? Lauren Keplinger, Colorado Springs
I don't believe in lazy. I think lazy is a symptom of something else that's wrong. Five or 10 lb. over your ideal aesthetic weight is normal. But when you're looking at 20-plus lb. over a healthy weight, that's not your body's metabolic set point, nor is it a question of laziness. You need to look a little deeper.
What advice can you give people to build confidence after weight loss despite the flaws excess skin and other body-image issues that come with it? Janette Kirton, Cottonwood Heights, Utah
Take credit for your accomplishments. When it comes to things like baggy skin or stretch marks, we're all going to grow old, get ugly and die anyway. At some point, it becomes about health and not aesthetics. Give yourself some credit instead of tearing yourself down.
Why did you become a personal trainer? Russell Wolff, San Diego
I fell into it. I was 17, training for my black belt. I would be in the gym hanging upside down from a gravity boot doing inverted sit-ups, and people would be like, "Oh, you must be a trainer." And I was like, "Of course I am."
You've said there are no magic weight-loss pills, but I see your name endorsing supplements. Why? Dawn Riley, Watkinsville, Ga.
It's not an endorsement deal. It's a licensing deal. What that means is I've worked with a lab, and doctors of course, to create supplements that I believe help enhance your metabolism. This isn't a magic pill, nor is it meant to be.
You spend a lot of time trying to eliminate junk food from other people's diets. Do you have any guilty pleasures? Ian Ingersoll, Minneapolis
There's a Turtle Mountain chocolate peanut butter coconut ice cream. And the occasional glass of red wine, but it has to be really good because I rarely drink. I'll definitely do a glass of wine and ice cream for dinner. It's been known to happen. Rarely! Rarely!