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5 Ab Exercises You Can Do At Work

More Ideas for Your Abs

Both Yeager and Bowling are big fans of the physio balls, the soft, inflatable exercise balls (also known as therapy balls) that you can use to replace your desk chair for a portion of the day.

"When you're sitting on the physio ball, you're constantly having to compensate for the instability of the ball," Bowling said [source: Bowling]. "So all of your core muscles -- your lower back, your obliques, your rectus abdominis, your hip flexors, even up to your rhomboids and your lats -- everything is firing in order to keep you steady on the ball."

Yeager agrees. "You're not burning tons of calories (sitting on an exercise ball)," she said [source: Yeager]. "It's not some magical way to lose weight. But it definitely reminds you to move."

And that is vital, especially for anyone who sits at a desk all day. Need more resources to plan your office ab workout? There's lots more information on the next page.