Activity sensors like the Fitbit, Jawbone Up, and Nike Fuelband are so passive: All they do is keep track of your body’s movements.

The Tao-Wellness Tao, by contrast, will be like a tiny gym in your pocket. Instead of merely tracking your activity, it also engages you in specific exercises, which you do by squeezing it. Tao-Wellness will be launching the Tao at CES 2014 this week, and will be starting a crowdfunding campaign for it.

That may not sound like much, but squeezing a small object engages your muscles by forcing them to oppose each other without actually moving, which is known as isometric exercise. It’s a key feature of many fitness regimens, including Pilates. With a pressure sensor inside and the ability to interact with iOS and Android apps, the Tao should be able to coach you through a wide variety of isometric workouts. Of course, it will also be tracking those workouts as you go.

The Tao will also contain a 3-axis accelerometer, like those in other popular fitness trackers, so it can track your movements the same way a high-end pedometer would. And it will have an optoelectronic heart rate sensor, giving it the ability to measure your heart rate by shining a light through your skin, and a gyroscope.

The device will have an OLED screen, a few LED lights, and exactly zero buttons: You’ll control it through gestures, by tilting and tapping, and through your phone. It will communicate with your phone via Bluetooth. It will weigh just 5.3 ounces, according to Tao-Wellness, and measure 3.26 inches by 4.38 inches by 0.93 inches thick. That might be a bit bulky to fit into your jeans pocket, but it’s not a lot larger than a typical smartphone, apart from its thickness.

The makers promise it will also have food-tracking capabilities built into the app, along with coaching utilities and even the ability to respond to voice commands.

All this will set you back $200 to $300 when it ships in Fall 2014.

There are some downsides to isometric exercise. While they’ve become popular in recent years, they can cause spikes in blood pressure, and they’re not good for conditioning your muscles to move quickly or for strengthening your muscles across their entire range of motion. So if you’re training for something, you can’t use isometrics as a replacement for drills or other kinds of strength training. But as a handy, portable tool for increasing your fitness, the Tao looks promising.

Tao-Wellness is a spinoff of a patent licensing company, EZD Productions. Its founder is Kostadin Yadev, a nuclear physicist by training, who has founded a number of other companies. The company has already received two U.S. patents for its technology and has 11 other international patent applications in process.

There’s an entertaining interview with Yadev about how he invented the Tao on the company’s press page.

Tao-Wellness will be showing off its product at CES at South Hall 2, Booth #26712.

Here’s a gallery of some more photos provided by Tao Wellness.

AI. Messaging. Bots. Arm yourself for the next paradigm shift at MobileBeat 2016. July 12-13 at The Village in San Francisco. Reserve your place here.