Trainer Charlee Atkins, C.S.C.S. , uses surfaces and stances outside of just the normal feet-on-the-ground setup to pack more muscle stimulation into each set. "No twists, no crunches, or plyos here, just a simple way of showing that youre getting an ab exercise in just about every exercise you do," she says of the setup.

The hack can be especially useful when you find yourself out of your traditional gym, or when you want to push yourself to focus on working your core in different ways. An added bonus: You'll also be using your legs, since you'll be firing your quads to stay in position.

To perform this particular series, which also works the shoulders, chest, and arms, you'll need a set of dumbbells along with your wall. Check out this adjustable set from Bowflex if you want to try it out at home.

Perform each exercise for 3 sets of 10 to 12 reps. If you can handle the pain, try stay in the wall-sit position for the entirety of the period, or for one full round through all of the moves.

  • Front Shoulder Raise
  • Lat Pulldown
  • Chest Press

Just be smart about how and when you use the wall. "I would save these for towards the end of your workout, after you've done the meat and potatoes (heavy lifts, etc.)," Atkins says. "Use them as a finisher, or similarly pre-meat and potatoes and use them as a warm-up for heavy sets."

Looking to switch things up even more? Atkins recommends sitting on a Swiss ball if you are focused on strengthening your core stability. Want to learn more moves from Atkins? Check out our series full of her workout tips, Try Her Move .