I try to work my abs in every single workout that I do, whether it’s a run, a HIIT class, or yoga. It always just feels like the cherry on top of my workout, since I can easily do a five-minute core workout to round out whatever else my sweat sesh might bring.  Working on your abs is a fundamental part of fitness, since a strong core can help with your posture and movement in general. But, according to fitness trainer Erica Ziel—a bonafide abs expert—you can actually overdo the ab work. Say what?

“The reality is while you are crunching your way to strong abs, you can actually be overworking your core and causing back pain and poor posture,” she tells me, reiterating the importance of having a strong core, since it’s the “main support for your spine, organs, pelvic floor, and entire body.”

That said, particular bodily dilemmas can stem from an overworked core, which is pretty much due to not varying the types of abs work that you’re doing. “If you’ve ever experienced back pain, knee pain, or peed your pants a little when you sneeze or jump rope, a weak deep core could be the culprit,” she says. “Many times the stories I see that deal with aches, pains, and imbalances involve people suffering from overdoing crunch-style abdominal exercises. They’ve been taught that crunches are the only way to strengthen your core.” The problem with overdoing just plain crunches is, according to Ziel, that you’re only working the surface muscles of the abs, which leads to an imbalance.

Other than this imbalance, Danielle Weis, PT, DPT, OCS, physical therapist with Spring Forward Physical Therapy, says that doing too many killer ab exercises can lead to delayed onset muscle soreness. “A lot of times people have the mindset of ‘go big or go home,’ or ‘no pain no gain’ and they jump into doing exercises that are too advanced. This can end up causing excessive delayed onset muscle soreness or DOMS,” she says. “Over time, doing exercises that are too hard can cause various muscle strains or overuse injuries, as people often overcompensate and perform exercises improperly.”

Ziel asks her clients the following questions to determine if an overworked core is the culprit:

1. 1.
   Are you experiencing any of the above symptoms?
2. 2.
   Do you find yourself slouching and unable to stand tall in a lengthening position for a long period of time?
3. 3.
   Do you find yourself feeling more stress or tightness in your hip flexors throughout your day, especially during workouts?
4. 4.
   Do you struggle to effectively engage and relax your pelvic floor muscles or engage your glutes to do your kegels?
5. 5.
   Do you often find yourself tucking your butt?
6. 6.
   Are you trying to connect with your deep core without success?

According to Ziel, if you’ve said yes to any of the above, there’s a good chance your core is unbalanced. “If you want to safely and effectively strengthen your deep core, begin incorporating exercises that engage all of it,” she says. “This means from the base of your pelvis up through your torso—this will allow you to strengthen your abs, fascia, and muscles from your pelvic floor through your abdomen, along your back, and around your ribcage.”

Working your deep core—rather than just the top of your abdominal muscles—means targeting your entire midsection. “I prefer plank slides where you are moving slowly and bringing awareness to your breath to help engage your entire core,” says Ziel. “By moving in a plank slide, you’re activating more fascia, which also helps to create length and space in your body. Core exercises involving rotation are wonderful for creating balance throughout the entire body while strengthening and lengthening those fascial layers.” Side planks are also good, notes Ziel, since activating your obliques and the entire side of your body is key. “And don’t forget your back,” she says.

Proper breathing is also key. “Breathing’s essential during core exercises to maintain appropriate blood pressure levels, use the correct muscles to stabilize and strengthen, and maintain proper respiratory processes,” says Weis.

If you’re still going to do some classic crunches in your ab routine, though, there are a few things to note: “Avoid drawing your belly to your spine and jamming your back into the mat,” says Ziel. “Instead, keep your pelvis a bit more neutral while zipping up your belly. Your movement will be smaller but you’ll feel the deeper layers of your core engaging. Keep your range of motion small to minimize the use of your hip flexors.” So, now: Maybe take a breather between your more well-rounded ab workouts for the sake of your bod.

That said, you can try this tempo training abs workout for a slower burn. Or take things up a notch by doing this Megaformer workout that requires zero equipment.