Fitness enthusiasts love the plank exercises for its ability to build strength and balance throughout the body, particularly in the core. The many variations of the plank make the exercise accessible to beginners and challenging for advanced exercisers alike. Because it integrates all the muscles of the core including the deep stabilizer muscles, the plank is often used as a back pain exercise.
Yet some people experience back pain when performing the plank. The following are reasons for back pain during the plank and ways to avoid it.
With any exercise, pain often indicates a form problem. All variations of the plank involve supporting your body in a straight line using either your hands or forearms and toes or knees on the ground. This engages the muscles of your core as well as your upper body. See the slideshow at http://www.fitsugar.com/8-Plank-Variation-Exercises-17932974?slide=0 to learn about plank variations. A couple of common form problems can occur during planks that you should be aware of.
Some people have a difficult time holding their bodies in a straight line and end up cheating by sticking their butts out when doing a downward-facing plank, forming an angle between the upper and lower body. While this initially makes the plank easier by taking responsibility off the core and distributing it to the thighs and lower back, it limits the effectiveness of the workout for that very reason and can lead to muscle strain in the lower back and thigh muscles. If you have trouble with the basic plank, try it with your knees on the ground for extra support and then work up to your toes.
Others may find that their stomachs begin to droop during the exercise. This means the arch in the lower back is increasing. This plank form faux pas is a sign of either abdominal weakness or overall fatigue. If the abdominal muscles are very weak to begin with, they may not be capable of supporting the lower back muscles and spine in plank position. Exercises like the bird dog, bridges and partial crunches can help to build them up. If you’re trying to hold the plank for too long too soon, your core muscles will grow fatigued and stop working properly, leaving much of the burden on the spine to hold your body up. Fatigued muscles are prone to painful cramps and spasms.
Finally, beware of holding your hips either above or below midline during side planks. Either of these mistakes places strain on your hip socket and sacoriliac joint.
Another common cause of pain when exercising is muscle imbalance. A muscle imbalance is present when one muscle group is tighter and more developed than its opposing muscle group (i.e. hamstrings and quadriceps). The tighter muscle becomes chronically tense thanks to muscle memory and inhibits the other, weaker muscle from firing (this is called reciprocal inhibition). Over time, the tight, inflexible muscle can pull on structures of the body and cause misalignment, since the opposing muscle is weak, overstretched and unable to produce a balancing counter force.
The main muscle imbalance to be aware of concerning planks exists between the hip flexors and glutes. If your hip flexors are stronger than your glutes (which they are in the general population), the workout they get from the plank may worsen the imbalance. You can experience back pain from this because the hip flexors stretch form the thigh to the lower back and, when shortened, pull downward on the lumbar spine. This can lead to anterior pelvic tilt, where the pelvis tilts downward in front, and increased lordosis, where the lumbar arch increases, harming joints and discs in the spine.
If you find that you have a hip flexor imbalance, self-myofascial release with a foam roller or other device can help restore flexibility to the muscles. This, coupled with bridges to engage the glutes will help restore balance to your pelvis.
Plank workouts are contraindicated for people with carpal tunnel syndrome, new moms who had their babies less than 6 weeks ago and, in some cases, people with a shoulder injury or shoulder instability.