ONE Exercise for a Killer Core

If you've been planking, crunching and tucking 'til you can't inhale without pain but still don't havethe core gains you want, it's time to try a different tact. While all those exercises are great for your core, they focus a lot on your anterior core muscles: your recti abdominis and hip flexors, specifically. They do draw on other anterior and side core muscles, but they don't hit them the way that this exercise can. We're talking about the Hip Thrust & Twist!

This killer core move targets combines pushing, twisting and squeezing to give you an insanely well-rounded core workout that will tighten and tone your waistline. Since it really targets your glutes, you'll enjoy the fat burning benefits of buildinglean muscle mass in your body's biggest muscle, and since it really hones in on your transverse abdominus (the muscle that sits like a girdle around either side of your waist), you're tightening up your midsection  — which incidentally makes this move amazing for people who havediastasis recti.

Other muscles worked with this move include your hamstrings, obliques and  — since we're loading up witha sandbag  — your arms and shoulders.

Try it out and feel the burn for yourself. Remember: that sweet, sweet heat means it's working!

Tips on form:

• Keep your glutes engaged.
• Keep hips in a straight line.
• Keep weight in your heels.
• Twist over as far as you can while keeping hips parallel with the floor.
• Keep the sandbag (or whatever weight you're using) at your lower chest: this will keep the majority of work in your core!

Ready to gear up and go? Awesome! Grab your Core Shred Bundle! This powerhouse of core training includes a weighted vest of choice, sandbag, stability ball, yoga mat, foam roller, The Pink Thing and all FIVE workouts in our newFive Day Fit Core Shred series. Your best abs ever are in the making, so get started!