Are you into High Intensity Interval Training (HIIT) workouts? Trying to up your game? Don\u2019t mind a robotic voice nagging you to move faster? Don\u2019t care if you look like a 1980s fashion victim at the gym? Then the new Moov HR Sweat ($100) was made for you.\nMoov HR Sweat differs from wristband devices that track your heart rate, like Fitbit Charge 2 or Apple Watch. Instead, Moov\u2019s product features a quarter-sized sensor that slips into a silicon rubber case, which itself is tucked inside a headband. Yes, a headband. I\u2019ll come back to that in a minute.\nWhy wear a sensor on your forehead? The head gives the most accurate optical measurements for workouts based on blood density, according to Moov. The company worked with the University of California San Francisco\u2019s performance lab and says its heart-rate readings compared favorably to the university\u2019s EKG tests.\nBased on my tests, here\u2019s a profile of the ideal Moov HR Sweat buyer.\n1. You\u2019re hyper-focused on HIIT workouts. Moov HR Sweat is designed to work with Moov's HIIT workouts, which are accessible in the free Moov app for iOS and Android. (As of this writing, the Android app hadn\u2019t yet been updated to support Moov HR Sweat.)\n Moov\nMoov HR Sweat doesn't currently non-HIIT workouts, such as on an elliptical machine or brisk walking.\n2. You\u2019re trying to up your game. Safely increasing your heart rate during workouts is a great way to improve your health. If that\u2019s what you\u2019re after, Moov HR Sweat may be for you, as the app\u2019s virtual coach coaxes you when to step up your pace to increase your heart rate, or slow down to decrease it.\n3. You don\u2019t mind a robotic voice nagging you. Another Moov HR Sweat differentiator is the app\u2019s robotic voice that pushes you during HIIT workouts, offering guidance based on current heart rate readings.\nThe voice \u2014 which has none of the sass of a Siri or Alexa, sadly \u2014 tells you if you\u2019re in, say, heart-rate zone 2 but need to be in zone 4. It didn\u2019t take long for me, someone who doesn\u2019t like being told what to do, to get irritated. (I\u2019ve never taken a boot camp fitness class and seriously doubt I ever will.) But I could see how others might find the heart rate feedback motivating. I did workout harder, in fact, because of the voice prompts.\n4. You don\u2019t care if you look like an 80s nerd. I\u2019m as image-conscious as the next person. And there\u2019s no way I\u2019m wearing a large headband to the gym. No one is going to tap me on the shoulder and say, \u201cHey dude, the 1980s called and wants its headband back.\u201d\nSo, at the gym, I wore a loose-fitting baseball cap, which partially obscured the big Moov headband underneath. Heads up, though: the combo gave me a headache that lasted several hours.\nFor serious athletes only\nMoov HR Sweat is a specialty activity tracker\/virtual coach for serious athletes focused on HIIT, vs. people who want an all-day\/night tracker. The heart-rate performance data it delivers is detailed. Heart-rate readings looked accurate, though they occasionally jumped dramatically, as if the sensor was trying to catch up with me.\nBut still: a headband?