Main muscles worked
most of the abdominal wall, especially the external and internal obliques, and the multifidii
Capsule description
with your feet and hips fixed, rotate your torso to one side, and then the other
Although not a commonly available machine, the rotary torso may be available where you train. As well as training most of the abdominal wall, the rotary torso works some of the small, intervertebral muscles, but it provides only secondary involvement of the quadratus lumborum. It’s an alternative to the side bend if the latter can’t be performed safely.
The rotary torso is commonly performed in a dangerous manner— with an excessive range of motion, and a rep speed that’s too fast.
Follow the manufacturer’s set-up guidelines, and fix the range of motion at what feels comfortable for you. After a few weeks your flexibility may improve, and then you may be able to increase your range of motion.
Smoothly move into each rep, take three to four second to rotate into the fully contracted position, hold it for a second, then smoothly return to the starting position over a further three to four seconds. Pause for a second, then repeat. Complete the set for one side, pause for a minute and set up the machine for the other side of your body, then complete the set for that side.
Starting (left) and finishing positions for rotation to the trainee’s right on the rotary torso machine.
Reminder
Study this book to learn about correct exercise technique, and then apply it consistently. If, however, despite using correct technique, along with a controlled rep speed, gradual increases in progressive resistance, abbreviated training routines, and adequate recovery time between workouts, you still experience joint or soft tissue irritation from a given exercise, substitute it with a comparable exercise.
Apply the first imperative of exercise: “Do no harm.”