If you think you’ve got a strong core because you’ve mastered every type of plank out there, try stepping it up by suspending your feet in the TRX straps.

According to a new study in the Journal of Science and Medicine in Sport, suspension training activates even more muscles than core exercises performed on stable and unstable surfaces. That’s right—it turns out the TRX straps step it up a notch further than the stability ball.

Researchers measured the activity of core muscles during four suspension exercises: hip abduction in side plank, hamstring curl, chest press, and the 45-degree row. All of the exercises activated core muscles, but the side plank with the raised leg produced the highest activation of most abdominal muscles.

Suspension training uses more muscles because it offers no support—in contrast to exercises performed on a flat surface or even an unstable surface like a stability ball or BOSU. As a result, suspension training improves core muscle strength and muscle endurance more than traditional core exercise.

Not convinced? Try it and you will be. Place your feet in the TRX straps and assume a side plank position. Raise your upper leg and hold it for 10 seconds. Repeat for 10 reps and then switch sides.

If you really want to up-level your core training, add suspension several days a week. Get creative—try side plank, side plank with leg raises, full plank, and full plank with knee curls. Your core will burn like never before.

Reference:
Mok NW, Yeung EW, Cho JC, et al: Core muscle activity during suspension exercises. Journal of Science and Medicine in Sport. Published early online February 19, 2014. doi:10.1016/j.jsams.2014.01.002