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Are your ab muscles really doing the work?

Abs, Abs, Abs...The gym is full of people focusing on flattening their ab muscles. At least they think they're working towards flat abs.

Abs, Abs, Abs...The gym is full of people focusing on flattening their ab muscles. At least they think they're working towards flat abs. But, by my observation on the gym floor at least 90 per cent of people are choosing the wrong exercises and targeting the wrong muscles. Instead of flat abs; most people's abdominal workouts are more likely to result in an unstable core and muscle imbalances.
Let's start with the biggest problem out there; ignoring the transversus abdominis (TVA) muscle; the MOST IMPORTANT abdominal muscle you have. These muscles, the deepest of the 4 layers of abdominal muscles in the body, run horizontally, encircling the abdominal cavity. Think of them as your built-in girdle. They are extremely important in providing stability to the spine. Weak TVA muscles will result in low back pain and an unstable core.
So, how do you activate these muscles? The two common methods are bracing and hollowing. Bracing refers to an isometric contraction of the TVA by contracting the muscles of the abdomen and holding them tight without movement. When bracing, imagine that you are getting ready to take a kick to the stomach. The goal is to tighten the muscles without sucking in. Hollowing refers to a technique to activate the TVA that occurs as you suck in and compress the abdomen. To perform this technique, exhale and contract your TVA to pull the area below your belly button gently back toward your spine.
When performing any type of spinal flexion (curl-ups) or extension (cobra) it is important to use the hollowing technique to avoid overusing the rectus abdominis (the six-pack) muscles. To ensure you are doing your curl ups correctly place one hand on your lower abs before you start the exercise. Engage the TVA, and then as you exhale, focus on maintaining that contraction as you lift your shoulders off the mat into a curl-up position. The area under your hand should stay flat. If you feel your belly "bulge" up into your hand, you know you have lost the TVA connection. The same is true for spinal extension exercises. When you are lying on your stomach, imagine there is a small thumbtack sitting just below your belly button. Gently draw the abdominals away from this imaginary tack. Your belly should not push down into the floor as you lift your head and shoulders off the mat.
That brings us to problem No. 2; overworking the hip flexors. The hip flexors consist of the illiacus, psoas major, pectineus, rectus femoris, and sartorius muscles. Their job is to bring the thigh and the trunk closer together. Walking, bending over, and stepping up are daily activities that all utilize these muscles. They are a strong group of muscles and without an awareness of them; they will take over the workload of many ab exercises.
Lower back pain and soreness in the groin are possible indicators that you are over-using the hip flexors and need to strengthen the abdominals. It is quite common to see beginner Pilates enthusiasts have an inability to keep their feet and legs on the floor when performing the roll-up. This is because the abs aren't strong enough to do their up and over contraction so the hip flexors take over to bring the trunk and thigh closer together instead.
Remember the full sit-ups you had to perform back in elementary school fitness testing; t he ones where a partner held onto your feet. To be honest, these have little to do with ab strength and way more to do with hip flexor strength. My suggestion is that the majority of people avoid any ab exercises that require you to anchor your feet under something. It is much more beneficial to perform a curl up focusing on the TVA than to perform a full sit-up.
Hanging leg raises are another exercise that most people should perform with caution. The act of pulling the knees to the chest is all about the hip flexors (especially the psoas), not the abs. It is only after the knees pass 90 degrees and the low spine begins to flex (think reverse curl) that the abdominals are actually involved in the exercise. And if your core isn't stable, the back will often overly arch when the legs are returning to the start position which can lead to injury.
If you've ever taken a Pilates class, chances are good that you heard the cue "relax your hip flexors." This is easier said than done but with awareness can be achieved. I suggest working privately with a certified Pilate's teacher who can closely monitor your form and help correct muscle imbalances.
To get the most out of your ab workouts, stay out of your hip flexors and focus on the TVA. You'll decrease your risk of low back pain and muscle imbalances and be on your way to a slim and flat belly. Your body will thank you for it!
Becky Cryne is a BCRPA certified Personal Trainer and Group Fitness Instructor, STOTT Pilates Mat and Reformer Instructor, CFP Pre and Post Natal Fitness Specialist, and ETW Yoga Exercise Specialist. She can be reached at