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The actress, author of "The Star Attraction" and host of "The Biggest Loser" says she's in the best shape of her life. Steal her tips for getting a slim, strong, sexy body.

Be up for a challenge
"When Loser went to Washington, D.C., I ran into Bob Harper in our hotel gym. I was psyched, thinking, he's going to see I've already gone for 35 minutes on the treadmill! He tapped me on the shoulder and said, 'You ready to do sprints?' I said, 'Bring it.' He put his hands over my machine and said, 'Run. Don't look. I'll tell you when to stop.' We did five sprints at all different speeds, elevations and lengths, including one 10-second sprint at 10 mph at 10 elevation! I never would have pushed myself that hard."

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Don't let gravity do the work
"The down on every move is just as important as the up. Take a sit-up, for example: If you sit up and then just flop back to the ground, you're wasting half your workout! Take three seconds to come up and three seconds to go back down. Do the whole thing. You'll see results."

There's no reason to have a baked potato, pasta or bread four times a day
"When I'm doing cardio, I can feel the difference in my body when I eat right and when I don't. Everybody talks about carbo-loading, but there's no reason to have carbs at each meal. Keep it light and eat what agrees with you. My prerun go-to: oatmeal with cinnamon and agave, or a banana."

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There is no such thing as can't
"I don't get to work out with the show's trainers that often, because they're busy. (Jillian recommended my current trainer, Steve Lee.) But one day, Jillian had me doing pull-ups. I was supposed to do 10, and by the time I got to 4, I was really struggling. I said, 'I can't!' Then she told me, 'Well, now you have to, and you're not leaving until you do.' I learned a lesson: I can finish what I start, and it's important to get to the other side. The confidence you gain will take you through the rest of your life, never mind the rest of your day."

The trainers from the show are in my head
"Sometimes, when I wake up and I start playing Scramble on my phone rather than getting out of bed, I hear Bob, Jillian and Dolvett [Quince]: 'You're being lazy. This is an excuse. Stop making excuses!' If I find myself going down that path, I say to myself, 'Go do it!' On days when I can't work out, I hear Jillian say, 'Ali, today wasn't your day. Don't beat yourself up.'"

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Skip sugary cocktails
"Margaritas have, like, a million calories. I've discovered you can have a really nice sipping tequila, like Don Julio 1942, with a little bit of lime or lemon juice and a little agave. It's less caloric—and it's delicious."

My go-to snack
"Greek yogurt with blueberries, agave and cinnamon. It feels like a treat!"

I only eat cheese when I can taste it
"Once I asked Bob for some nutrition advice, and he told me to pay attention to how much cheese I was eating. I was like, 'What are you trying to say? I really don't eat that much cheese!' It turns out I was eating more than I'd realized—in things like my eggs and sandwiches and salads, where I couldn't even taste it. Because I wasn't appreciating it, much less noticing it, it was such a waste of calories. That helped me slim down a bit. Now I'll just sprinkle a little on top of dishes where I can actually taste it."

Gear totally matters
"When you start running, you need pants that fit well so you don't chafe. My fave: Moeben. I'm also obsessed with my Newton sneakers, which are made for distance running [if you land on your forefoot]. They're the best running shoes I've ever worn!"

Be practical
"I don't need to have a perfect suntanned body. I just want to be able to run around without clutching a towel because I feel self-conscious about how I look. If my body's good enough for that, it's good enough for me!"

Allison's 7-day fat-burning plan: 

Monday: Fight. "I work out with my trainer for about 90 minutes. Lately we do Eskrima, a type of ancient Filipino fighting that involves lunges, squats and a 2 1/2-foot stick."

Tuesday: Hill Climbs. "When I don't have much free time, I'll take a 45-minute run on a hilly route. The hills are so good for your butt—it's an extra benefit!"

Wednesday: Chill. "If I get home at 9 p.m., I just say, "I worked out yesterday. I'm going to do it again tomorrow." I'm happy to take a free pass."

Thursday: Longer Run. "I'll go for 6-7 miles in the morning if I can get it in."

Friday: Tone at Home. "I do DVDs. One of Bob's has a move where you lie down then stand without using your hands. It's so hard, and I'll think, He's looking at me!"

Saturday: Pedal Power. "I'll do an 18- to 20-mile bike ride. I live in fear of getting doored like Paul Rudd in 'This Is 40.'"

Sunday: Mid-Distance Run. "I'll go 5-6 miles. I also meditate at home for 20 minutes—no music, no thinking about what's next. I'm learning to be still."

This article originally appeared on Self.com.