Mark Jansen is still in the running for the $500,000 grand prize on Big Brother's nineteenth season.

Mark is a 26-year-old personal trainer from Grand Island, NY, who has a tough-guy persona yet considers himself a teddy bear.

Mark has managed to dodge bullets so far in the Big Brother game because he has yet to become a target although he continues to turn his back on alliance members and betray them.

Mark ditched Cody Nickson when the U.S. Marine needed him most, and he also voted his pal Dominique Cooper out of the house in order to save himself.

More recently, Mark also got into an argument with Josh Martinez over a silly round of pool. However, Mark is loyal to his showmance partner Elena Davies and seems to be holding strong in his alliance with Paul Abrahamian, Matt Clines and Raven Walton.

Below is a list of 6 facts Reality TV World has compiled about Mark Jansen:

- Mark played Division 1 football for one year at the University of Buffalo, where he graduated from and received his college degree.

- Mark weighed between 330-340 pounds after college, but because he always wanted to be in the fitness industry, he lost over 100 pounds and then got into bodybuilding.

People started asking him how he achieved such weight-loss success, and once he started helping people, he became a personal trainer.

- The Big Brother houseguest predicted the ladies would be his downfall on Season 19, and the fact he's incredibly honest.

- Mark lost his father at a young age and was raised by his single mother, who died when he was only 17-years-old.

If he wins the $500,000 grand prize, he plans to start a foundation to help single moms or children with deceased parents.

- The personal trainer adores his grandparents and enjoys playing chess. While in the Big Brother house, he misses bowling with his grandpa. 

- Mark is a bodybuilder who studied abroad and went to an NFL regional combine.