It should be a crime for a gym to have a seated twist machine. It's almost guaranteed to cause a spinal injury, and it's not even very effective at strengthening your core muscles.
Yet, many fitness facilities around the country have this old-school piece of equipment. At my local gym, I've personally seen a wide variety of people using the seated twist machine—there's a kneeling version that's just as bad—from teenagers to old-timers. And I cringe every single time.
So what's the issue with the machine that looks like a high-tech torture device? We spoke with world-renowned spinal biomechanist Dr. Stuart McGill to find out.
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Problem 1: Twisting Damages Your Discs
Seated Twist Machine 1
The seated twist machine is based on the idea that to train the obliques and improve rotational power, you need to perform exercises that involve some sort of rotation or twisting through the core. When you use this machine, your upper body stays in a fixed position while your lower body rotates on a swivel, creating a twisting motion through your lower torso, which you can see here.