If Your Core Shakes Like a Leaf During Ab Work, Here's Why — and How to Make It Better

For me, it's usually about 20 seconds into a plank that the telltale shivers start to run through my core. Muscle tremors are something a lot of us learn to embrace as a sign that we're working our abs (or arms, or legs) as hard as we can; when you sign up for an ab-shaking move, you know you can expect a true challenge. But if you've ever wondered why exactly your abs shake during a hard core workout, you're not alone. This phenomenon is common and not anything to worry about, but knowing why it happens can help you make your workouts even more effective.

Why Do My Abs Shake During Core Work?

When your core muscles start to shake, it's usually because they're trying to stabilize your body during an exercise, said Tom Holland, MS, CSCS, exercise physiologist and fitness adviser for Bowflex. "Muscle shaking is common and to be expected, especially when you are performing a new movement or one that is particularly challenging."

It's related to both your muscles and your brain, Tom explained. "The brain is 'learning' how to connect to and recruit the specific muscle fibers involved in the exercise, while the body is building strength and becoming more efficient at the movement itself."

How Can I Get My Abs to Stop Shaking During Core Work?

It's normal for your core (or another muscle) to shake during a workout and not necessarily a sign that you have to stop, although you can definitely take a break if you need. "You can continue with the exercise until your form begins to become compromised," Tom said. "Then it's time to stop."

If the shaking bothers you (or if you're just wondering when it's ever going to stop), Tom assured us that the more you perform the exercise, the less shaking you'll have to deal with. Your muscles will get stronger and you'll get more efficient with practice.

But if you still have 30 seconds to go in that plank and want to minimize shaking, Tom said you can help to stabilize your core "by tightening your abdominal muscles while continuing to breathe." It'll feel like you're pulling in your belly button and preparing for someone to punch you lightly in the stomach.

To build up core strength (and minimize shaking down the line), Tom recommended planks as "a phenomenal exercise to build core strength while making the neuromuscular connections in the core." Try his quick, one-minute plank routine to challenge and strengthen your abdominal area.