It's a new spin on an exercise you may already be familiar with.

By Rozalynn S. Frazier
April 22, 2015
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Did you happen to see that crimson gown Blake Lively rocked on the red carpet at the Age of Adaline premiere on Sunday? Or perhaps the sheer, leg-baring ensemble she changed into for the movie’s after party? Two words: absolutely stunning. (Adaline is Lively's first flick since 2012’s Savages, and it hits theaters this Friday.)

The Gossip Girl alum gave birth to her first child, daughter James, with husband Ryan Reynolds in January.

We know, you kind of want to hate her right now. But don’t, because the starlet works hard for that body. And, lucky for you, we know a toner that has helped keep this 27-year-old star’s stems sleek, sculpted and ready to show off at a moment's notice, straight from one of her trainers.

Add this move to your current training regimen, doing two sets, four times a week, and you’ll notice a difference in just eight weeks.

  • Get Blake Lively's Gorgeous Gams
  • Trainer: Bobby Strom
  • Go-to move: Hamstring Curl with Resistance Ball and Yoga Block

“It's been done before but my spin on it is working the abductors and adductors while performing the curl,” explains Strom. Pushing outward on the band works your glutes and outer thighs and squeezing the yoga block works the inner thighs.

How to do it: Place a resistance band around your thighs, just above the knees. Lie on your back with your calves resting on a resistance ball, arms by your sides, and palms facing down (a). Lift your hips off the floor; slowly roll the ball toward you, bending your knees, until feet are flat on the ball (b). Roll the ball back out. Do 20 reps, keeping your hips off the floor the entire time.

Slowly lower your hips to the floor, remove the resistance band, and place a yoga block (or a hardcover book) between your knees (c). Repeat the hamstring curl (d) for another 20 reps, then lower your hips to the floor.

Illustrations: Jason Lee