My gym doesn’t have a crunch machine. I have strong abs, and I like to do resisted crunches, but stacking 45-pound plates on my chest can be awkward. Do you have an alternative?
—Mike K., San Luis Obispo, CA

I’m a firm believer in adding resistance to ab exercises to build strength and accelerate muscle growth. Your rectus abdominis (the six-pack muscle) and obliques are like any other muscle group: They need to be trained with a variety of resistances and rep ranges. In fact, a recent study found that subjects performing a body-weight–only ab workout several times per week for 11 weeks experienced no significant increases in abdominal strength.

Holding weight plates, dumbbells, or medicine balls while doing crunches will increase your resistance, but these methods can limit the amount of weight you’re able to use. Your solution? The Smith machine crunch.

How to: Smith Machine Crunch

  • To perform this move, place a bench in the middle of a Smith machine.
  • Lie faceup on the bench with your knees bent and your feet flat on it, with the bar over your upper abs.
  • Keep your back flat on the bench and hold the bar at arm’s length.
  • Use your abs to explosively raise your torso as high as you can, pushing the bar up as your body rises.
  • From the top, slowly lower your upper body back to the bench and repeat for reps.

Quick TipWhen the gym is busy and there’s no flat bench available, you can perform the Smith machine crunch on the floor.

The Workout

Exercise Sets Reps Rest
Hanging Leg Raise 3 To Failure 1-2 min
Smith Machine Crunch 3 8-12 1-2 min
Side Plank 2 per side 60-90 sec 1 min