Beast Sensor reviewed: When all you want is to get stronger, better, faster—now

Valentina Palladino

Valentina Palladino

There still aren't many fitness trackers that are suitable for a gym atmosphere. While devices like the Atlas Wristband have pushed the category forward, the Fitbits and Garmins of the world still mostly focus on cardio exercises while throwing a few trackable moves like "weight training" into the mix. The $250 Beast Sensor is one of the newest devices to target gym-goers, specifically weight-room junkies.

The Sensor is a small module that, when attached to your wrist, back, or gym equipment, measures speed, power, and a number of other atypical metrics to help you achieve beast-like fitness goals. The Beast Sensor is built on the principles of velocity-based training, which is a way of working out that only a select group will be able to use (and want to use) to their benefit. I spent some time with the Beast Sensor in my gym and can say it's a capable fitness tracker, but only certain people will find it invaluable.

Design: Little sensor, lots of power

Despite its pseudo-intimidating name, the Beast Sensor is diminutive. It's a two-inch long neon yellow module that holds three accelerometers, three gyroscopes, and three compasses, with a lithium ion battery inside. The Sensor has the company's logo in black, and a small indicator light flashes when the sensor is properly connected to your smartphone via Bluetooth. The indicator also flashes when the Sensor charges via its microUSB port. On top of everything the Sensor packs into its tiny module, it's also magnetic, so you can attach it to its included wristband and any gym equipment you want, including barbells and metal weight machines.

The sensor feels weighty in your hand, but when you slide it into the pocket on the included wristband, it becomes nearly undetectable. The wristband isn't anything special—just a black stretchy band that you can secure with its Velcro end. The open-ended pocket also has a magnet to ensure the Beast Sensor doesn't fall out when you're completing a set.

The Beast Sensor is in the same general category as the $250 Atlas Wristband in the sense that it's a gym-based fitness tracker that emphasizes weight training. However, while the Atlas Wristband has a PMOLED display and focuses on rep counting, the Beast Sensor uses its module design and accompanying algorithms to track velocity and performance. It records workouts and gives feedback based on the principles of velocity based training (VBT), which is a way of using speed to determine how much weight you should be lifting on any given day, depending on your end goal.

For example, let's say you're lifting to get stronger: under the guidelines of VBT, if you're lifting too quickly on a day when you feel energized for a workout, you should increase the amount of weight you're lifting in order to bring your speed down and maximize the strength you're gaining from each individual rep. The Beast mobile app has a Cliff-notes VBT explainer in it, and the company has the same information on its blog.

We'll get into the specifics of how the Beast Sensor works in relation to VBT in the following sections, but its design is in line with its intended purpose. Unlike the Atlas Wristband that you wear almost exclusively on your wrist, the Beast Sensor can and should be moved around. Wear it on your wrist while you do bicep curls, place it on the weights when you do leg presses, or put it on your back in the optional Beast Vest to record pull ups and push ups. The Sensor may seem less user-friendly since it doesn't have any controls on the module itself, but it's more versatile than you may initially believe.

• Beast Sensor with included wristband. The sensor module is magnetic.

  Valentina Palladino

• It has three accelerometers, three gyroscopes, and three compasses inside.

  Valentina Palladino

• The small power button turns the sensor on when you want to record a workout.

  Valentina Palladino

• The Sensor charges via microUSB. It can last up to eight hours on a single charge.

  Valentina Palladino

Features: Making the weight room your own

The Beast Sensor combines its motion tracking guts with algorithms and user-provided information to judge how hard you're working while you exercise. But first, you have to make sure you're doing exercises it can track. While the app has a list of trackable moves, you can add your own, too. When I took the Beast Sensor into my gym, I added the hip abduction machine to its list. With the Beast Sensor attached magnetically to the side of one of the moving leg rests, I started a workout within the app only to find that the sensor wasn't picking up my reps.

Placement is key for the Beast Sensor. I had better luck when I placed the sensor on the stack of weights in the machine. While I moved on from the hip abduction machine, I used the sensor in this way on a bicep curl machine as well as an abdominal curl machine. Every time the weights moved up and down, the Beast Sensor captured my reps in real time (you can follow along with the app opened on your smartphone). The Sensor also captured my speed in meters per second, and power in watts changed with each rep.

The same thing happened when I slapped the Sensor on the metal handle of a dumbbell. Depending on the size of the dumbbell, I kept the Sensor just to the side of my hand grasping the handle, or I put the sensor on the handle directly underneath my hand so I could grasp both it and the handle at once.

A few exercises won't be accurately completed unless you have the Beast Vest, which lets you attach the Sensor to your back. I tried doing some push-ups with the device in its wristband, but no reps were recorded. While the Sensor's design makes it easy to stick on different surfaces, you have to figure out which position is best for the exercise you're completing before you can get an accurate reading. The Beast Sensor is similar to the Atlas Wristband in that way, even if the former was designed to be placed on external objects as well as your body.

The Beast Sensor is also similar to Atlas in that it gets tripped up from time to time. But rather than missing reps like the Atlas, my Sensor counted a few extra reps during some workouts. Thankfully, I never finished a workout with 10 or 20 more reps than I actually completed. At most, my Sensor mistakenly counted one or two extra.

The Sensor has five options of activity tracking modes: Performance Tracking, which simply monitors your movements; Hypertrophy, for bulking up muscle to gain strength and size; Max Strength, for increasing the force you can output in each movement; Power, for performing under the ideal strength and speed conditions to maximize power; and Velocity, for increasing the speed of your movements.

The variety of choices is confusing to understand at first, but when you break down each mode, you can easily choose the best for your intended fitness goals. Next to each mode in the app is a question-mark bubble that you can tap to get more information. That's invaluable. Underneath each mode title is a catchy tagline like Max Strength's "grow as strong as a bear." I wish the company didn't try to be cute and instead put accurate, simple descriptors underneath each title so that VBT newbies wouldn't have to search for basic information.