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This simple tool will zap your climber core


The Stealth Plankster is a padded, triangle-shaped plastic wedge that swivels on a base, with a recess for your smartphone connected to games on the Stealth Fitness app.


Ergonomic base is stable, easy-to-use, and relatively comfy, with good padding for your hands or forearms. // The exercises are very effective and will cultivate a burn in just minutes, leading up to a stronger core girdle over the weeks and months. // Great variety of games (with Premium membership) means you can mix up your workouts.


You really need the Premium membership; the four free games get old fast. // It might be nice to have rest periods or “timeouts” built into the app’s timer; I sometimes found myself so bathed in lactic acid in my trapezius muscles and shoulders that I had to drop to my knees and rest for a few seconds.

Our Thoughts

This is a very effective, fun-to-use plank-style core trainer that works via an app and video games. It makes a great supplement to floor- or TRX-based core training for climbers. Note: If you have kids at home, they will quickly find a way to “hack” the trainer and just turn it into a video-gaming console, namely by dropping their knees to the ground but then still playing the games and swiveling around. My younger son can “plank” for a half-hour this way…





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The Stealth Plankster sets the core on fire via an app and video games

Climbing + the Core

As anyone who boulders a lot or climbs on steep sport routes knows, the stronger your core, the better. A strong core lets you more easily connect the neuromuscular chain from your toes up through your fingertips, for smoother, stronger movement. But core training is, well, monotonous—and often painful. It’s kind of a drudge.

The Stealth Plankster, a wedge of padded plastic that swivels inside a base, aims to make planking—forearm or regular—more interesting. Your phone sits in a recess on the trainer, and you use the Stealth Fitness app. The app comes free with four basic motion-activated video games or an upgrade to premium for $25 a year (right now this gets you an additional 16 games). The games, which often involve forward travel (a motorcycle road blitz) or linking dots (a Pac-Man–style game), help you forget that you’re planking. Or they at least take the sting out while you suffer. They also get you moving about, in various directions, to target side muscles like the obliques.

Stealth Core Workouts

The workouts have been quite effective—just a few minutes and I’m blasted, especially in the “six-pack” area. I’ve been doing it almost daily for a few months, as a supplement to my usual core work (YouTube videos—thanks, Pamela Reif and Rebecca Louise!), and I have seen benefits. These include greater core stability both front-and-back and to-and-fro, which I have noticed while MoonBoarding or on very steep sport climbs. On a project in the Flatirons, for instance, I’ve been able to segue into a foot-cut and distant left-foot stab onto a sloping edge with much greater control; I find I can hang there an extra beat on the crimps, mid-air, to take that key second to situate the foot perfectly. The Stealth also helps with definition, if you’re a “shirt off, beanie on at-the-gym”–type climber.

Blast It!

The best core work for climbers seems to be active, in-space drills that simulate the dynamic way we use our cores on rock, and tightening the core girdle with the Stealth certainly falls into that category. It’s a great complement to your climbing and other core training. My only issue seemed to be a major lactic-acid build-up in my shoulders and traps—though, holding regular forearm plank on the floor for minutes on end will also set your upper body on fire! In any case, this issue has gotten better with adaptation and can be obviated by using the trainer with straight arms (a slightly different workout) or switching back and forth between forearm and regular plank.