14 Time-Saving Exercises
Image: Beth Bischoff
13. Mountain Climbers on a Stability Ball
Because they combine cardio and core work, mountain climbers are a popular form of punishment doled out by trainers during circuit routines. Increase the intensity of the exercise by doing them on a Stability ball or BOSU (bubble side down). The instability created by the ball puts extra stress on your core, says Ettinger. “You’ll definitely feel your abs working as you bring your knees in and out."
1. Place a stability ball against a wall. Assume a pushup position with your arms straight and your hands resting on the ball. Lift your right foot off the floor and slowly raise your knee as close to your chest as you can.
2. Lower your right foot back towards teh floor, returning to starting position. Repeat with your left leg. Alternate back and forth for at least 30 seconds.