Jessica AlbaZuma Press

Jessica Alba isn’t slacking on her regular workout routine just because she’s got a baby on board. Reebok master trainer Yumi Lee told Instyle how she helped the actress—currently pregnant with her second child—modify her regular routine to accommodate the bump. “I have Jessica doing exercises to keep her core strong and work on her balance,” Lee told us. “We do curls using a stability ball, single leg balance movements and compound moves like squat thrusters.” Lee said Alba enjoys a simple plank exercise using a stability ball, which helps maximize muscle tone while improving balance.

While prenatal exercise has benefits for both mom and baby, Lee maintains that there are several things pregnant women must keep in mind.  “Monitor your heart rate and body temperature and be careful when attempting moves that focus on the back, or involve twisting,” the trainer advises. The added bonus of keeping up your gym visits while you’re expecting: Lee says that most women who practice pre-natal exercise bounce back into post-pregnancy shape faster than women who don’t.

Try Jessica Alba’s Pregnancy Plank in 3 Easy Steps!

1. Place your forearms on top of a stability ball. Your shoulders should be positioned directly above your elbows.
2. Extend your legs straight out behind you and balance on your toes, trying to keep your back as neutral as possible.
3. Slowly lift your chest off the ball so that your upper body weight is supported by your forearms. Draw in at your belly button, squeeze your glutes, and hold the position for as long as you can, working up to 1 minute.

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