For "Biggest Loser" trainer Bob Harper, a healthy body and a healthy world go hand in hand. "I am a firm believer in buying animal proteins that are organic and grass-fed and shopping at farmers markets is totally the way to go. I also have a little garden in my back yard that I love using," says Harper. "I really do believe in taking care of this Earth we live in any way we can. When you put in positive energy to your world, positivity will definitely come back to you. A healthy lifestyle is all about taking care of yourself and the planet."

Harper describes the 12th season of the NBC weight loss competition, which is nominated for an Environmental Media Award this year, as a "Battle of the Ages, Old vs. Young vs. the people in the middle. We are about to put every generation to the test this season and it is not to be missed. Of course there are gonna be tears, drama and confrontation but there will also be weight loss and inspiration for every viewer watching." Being part of that transformation is his biggest reward. "I love that I get to be a part of our contestants' overall transformation. I love what I do because I believe in the power of change. I believe that we are all capable of living the best life we can with the need and want to make it happen. I see this every day that I go to work and it inspires me to be a better person."

He pushes himself to exercise just as hard as he pushes the contestants with CrossFit workouts at the gym, "because it clears my head and makes me feel strong. I believe that we should always try to find a way to push outside your comfort zone," says Harper, who used to be a vegan but has incorporated animal protein like eggs, fish and some dairy into his diet of late, but it always includes "tons of veggies, and at night I always cut out the carbs." His best advice? Find something that you love to do and you will be more likely to stick to it. "The bottom line is that for many people, fitness can be a chore, but focus on how great you feel afterwards and know that you are doing something positive for yourself that has huge benefits."

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