Kettlebell Twists Twist Your Way to a Superior Core

By Stephen E. Alway, Ph.D., FACSM
Illustrations by William P. Hamilton, CMI

When it comes to ab training, the side muscles are often neglected. Endless sets of crunches and leg raises will strengthen the anterior abdominal wall, but these exercises won’t directly hit your side of your core, or obliques.

So how can you strengthen and tone your obliques? Kettlebell twists are the answer. The obliques are strongly activated during twisting functions, as well as straight trunk flexion. The kettlebell twist is an extremely effective core exercise because it targets the twisting functions of the oblique muscles. Add it to your workout today!

Exercise: Kettlebell Twist

1. Stand upright, with your feet about shoulder-width apart for good balance.
2. Hold one kettlebell in front of your chest with both hands. Lift your elbows out to the sides at shoulder height, with your palms pronated (towards your torso). Pull the handles of the kettlebell as if it were your goal to pull the handles apart. This will keep tension in your upper body as a secondary activator of back, shoulder and triceps muscles.
3. Keep your hips pointed forward. Take a breath, then begin to exhale as you rotate your torso, shoulders and head to the left as far as you can (do not twist your neck, but keep your chin over the sternum and make sure that the twist is from your waist). Keep the elbows and upper arms at shoulder height throughout the twist.
4. After twisting as far as you can in one direction (remember: do not let your hips twist), inhale as you twist back to the center.
5. Continue and now exhale as you twist to the right as far as possible. Continue the sequence of twisting to one side, then the other, and complete 12-15 twists on each side before taking a short break.

You should avoid holding your breath during the exercise, as this would increase intra-abdominal pressure and prevent the oblique muscle fibers from fully shortening during each twist. Instead, take a breath and then exhale as you are twisting to each side.

If you play weekend sports, you might occasionally experience pain in the lateral abdominal wall, and this might be an indication of micro tears resulting from straining the oblique muscles. This can occur by sudden and forceful twists, quick lateral flexion or sudden stretches that are often a part of many sports like softball, tennis and soccer to name a few. Tearing of the internal oblique muscle from the undersurface of one of the lower four ribs or costal cartilages causes side strain injury. This is a painful condition, but the good news is that if your weekend activities involve sports that would be prone to side injuries, then these can be drastically reduced by strengthening the oblique muscles with kettlebell twists. On the other hand, if your goal is instead to tighten and replace a soft waist with a firm one, while strengthening your core, then the kettlebell twist will become a new favorite exercise.

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