by David McAlpine

It was finals week on The Biggest Loser as the trainers tried to wrap up their weight-loss education, they wanted to each give the contestants one last test in several areas that they've experienced on the ranch.

First was Bob, who gave the final five a test in spinning, both setting up the bike and then proper technique of doing it. Irene was a little clumsy in setting up the bike, and Jay got way too into it for Bob's liking. However, Austin, though nervous, earned high marks, while Hannah and Olivia earned perfect scores for the test.

Brett was next, who asked a lot of book questions about exercise and nutrients. I don't know how some of these contestants knew these, considering I'm a science major and I was clueless on a bunch of them! Everyone walked away with solid scores in the 80s, leaving it a very close race.

Cara was third, engaging the contestants in (what else?) a fighting test. But this time it wasn't boxing, it was headbutting. Techniques in how to headbutt. Luckily, everyone was able to master them fairly quick, earning good marks from the boxer.

Last was JIllian, who wanted to appeal to their emotional side. She's been the motivator this entire time (in her own way), so now she wants to see them motivate her. She turns the tables and sees how much the contestants can try to relate with someone else on a one-to-one level. Because they've been at it for so long, everyone also scored well on this portion.

But there was still one more test: the Biggest Loser Ultimate Workout for the Xbox 360 Kinect test. I mean really, what's a Biggest Loser episode without shameless self-promotion, right? Basically, it was 5 minutes of sumo squats in front of a screen. Hannah came out the winner for endurance and form, but Olivia ended up winning the whole challenge, taking home $10,000.

Jillian's prey of the week was Jay, because she thinks that Jay has been flailing ever since he got back on the ranch. That's not acceptable to her, so she really railed on him this week to get him going.

This week's other challenge was a brutal one: There were 4 giant stairs and 100 sandbags. Each contestant had to get 25 sandbags on each stair, using the pile of sandbags to get on the next stair. Of course, that meant transporting the other sandbags up to the next stair, too.

Even with editing, NBC couldn't make this look close. Austin won by a mile, giving him a one-pound advantage at the weigh-in. Even though everyone eventually finished the challenge, no one felt safe, especially since one of the strongest competitors had yet another edge.

At the weigh-in, Ali offered Olivia to trade her $10,000 for a one-pound advantage and vice versa for Adam. They both considered the deal, but neither took it, much to the dismay of Jillian (for Olivia). The weigh-in results were as follows:

Jay: -9 (-3.53%)
Irene: -5 (-3.29%)
Olivia: -5 (-3.16%)
Hannah: -4 (-2.60%)
Austin: -1 (-0.42%)

Not surprisingly, all the Bob and Jillian regulars voted for Austin to leave, sending the sisters into the final four together.

At home, Austin is down to 230 pounds and he's trying his hand at mixed martial arts. He's also speaking at local schools about weight loss and the importance of health.

The Biggest Loser airs Tuesdays at 8/7c on NBC.

(Photo courtesy of NBC)

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