The workout is just seven minutes, but Julia Hayes is pushing hard: 30 seconds on, 10 seconds off.
It s a series of exercises, scientifically researched to go in this order. Ninety pounds later, she's feeling great.
My son weighs 82 pounds. I picked him up, and got on the scale with him, I struggled to hold him. I then put him down, and got on the scale, and that's how much I've lost, she said.
Her secret: strength training and high intensity intervals. All of which are built into this short seven minutes, with only a wall, chair and weight required.
I enjoy the fact that its quick so I can get it over fast, said Hayes.
Jacqui Bliss, a trainer and co-owner of Anytime Fitness, warns some of the exercises aren't for beginners, but she says the workout's scientific foundation is good.
It's going to improve how well your body utilizes oxygen, she said. People get it shape faster doing intervals.
From planks, to high knees, the seven minutes is supposed to be unpleasant. Hayes has to push hard.
It forces you to work hard, then rest; it's all about taking your heart rate up high and then down low. So when you're done with that workout, although you may have not burned as many calories, you're going to burn more throughout the day because your body is trying to catch up to get back to normal, said Bliss.
But like most workouts, it's not a magic bullet. Bliss suggest to mix in cardio some days. And warns, eventually you'll have to change it up.
I think the longer you do this work out the less effective it will become, she said.