When someone calls Bob Harper's clients "big losers," he usually responds with an enthusiastic "Thank you!" In his line of work, being surrounded by losers means he's got his mission squarely in front of him.

Harper is one of the personal trainers responsible for whipping contestants into shape on NBC's hit reality show The Biggest Loser. Each episode depicts the drama of how overweight, out-of-shape contenders transform their bodies, their health and ultimately their lives with proper diet and exercise. In the end, the biggest loser is the biggest winner ‑- and Harper is with him or her every step of the way.

We caught up with Harper just before he began taping season two of the show to ask him a few questions about his methods and philosophies.

How did you score such a great gig?

I got a call one day out of the blue from a casting director at NBC informing me about the show and asking me to come in to audition. I went, and when I found out what the show was really all about ‑- getting healthy and losing weight the good old-fashioned way, by diet and exercise ‑- I wanted it. It became a big focus and priority to land this job. The audition process lasted approximately six weeks and I finally got the call asking me if I wanted the part. It was a great day.

What's the biggest challenge working with "big losers"?

I think the biggest challenge of the show was getting a group of six people that had basically let themselves go and help them gain control of their lives. I approached my team from the inside out. I told them it wasn't going to be just about what to eat, what not to eat and how to exercise. They had to get down to the why of it all ‑- why we do the things we do when we are in any way triggered by life. It was challenging to get them on board with my way of thinking.