Are Sit Ups Bad for You?

This article is a direct follow on from part one, it will make more sense if you read part one first.

The core is an anti-motion motion device, it transmits force and resists twisting, flexing and extending.

So imagine your abdomen is a sushi roll.

The prawn in the middle, that's your spine, the rice, that's the deepest layer of your core muscles, muscles like the TVA and multifidus and then lastly the nori roll on the outside, that's the superficial muscles. Think of your six pack, your rectus abdominus, and erector spinae.

Now here's the trick, most people think the thing that makes sushi sushi is the seaweed, but it's not, it's actually the rice. Without the rice, you just have a seaweed and prawn salad. It's the same with the core, people see a six-pack and they assume that's the key to a strong stable core and healthy spine. But it's not, a strong stable core starts in the rice.

When it comes to stabilising the spine, the body recruits the deep muscles first to lock the spine down and hold the organs in place. The TVA, multifidus, internal obliques and pelvic floor switch on first. Only once these deep stabilisation muscles are engaged and everything is set can the core start thinking about transferring force from the legs or arms through the more superficial muscles.

This system of recruitment is dependent on the nervous system running the software smoothly. Combine a heap of sitting and a large dose of inappropriate core exercises like sit ups, crunches and Russian twists (exercises that create motion through the core as opposed to resisting it) is like trying to make sushi backwards, changing the order the muscles are recruited. 

This reverse recruitment sequencing is a software virus in the nervous system, creating a pattern of outside-in activation, where the larger superficial muscles of the core (like rectus abdominus) are recruited ahead of the deep stabilising muscles (like the TVA) leaving the spine unstable and susceptible to injury.

Check out part 3 for our effective and functional 5-minute abs workout.