As one of America's toughest trainers, The Biggest Loser's Bob Harper is hardcore. He's taken 100 pounds off a man in a mere seven weeks (remember Rudy?), breaks contestants down and builds them back up during Last Chance Workouts, and gives us the skinny with his Trainer Tips on NBC. Now he's focused on challenging the country to a 24-hour vegan cleanse.

Bob's latest tweet reads, "Your Challenge today is to go the next 24 hours, starting now eliminating ALL animal products. Good for your heart AND the environment!!"

Go vegan? But how? Well, in the famed words of Bob himself, "Just stop talking and do it!" Or, you know, a vegetarian/vegan starter kit works just as well.

Written by Christine Doré

As an obsessed fan of The Biggest Loser, I just about jumped out off the couch last night when America's toughest trainer Jillian Michaels walked onscreen wearing PETA's ever popular "Fight Breedism" T-shirt.

For the whole first half of the show, while the contestants were filming in Washington D.C., Jillian rocked the compassionate message across her perfect abs—even during the workout! Jillian is one of the most inspirational women on television and knowing that she is fighting against obesity and animal homelessness rocks my world!

My Jillian-mania escalated to even greater higher heights when she took the winners of the challenge to Subway for lunch and told the crowd that she recommends the vegetarian sub because it's her favorite. Fellow trainer Bob Harper is already vegetarian, so I'm beginning to see a pattern here … no wonder they look so good.

Written by Christine Doré