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New Wearable Device Tracks Lactate Threshold

The first wearable lactate threshold sensor looks inside your muscles to track lactate levels.

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A new wearable device to detect your lactate threshold—no blood draw required.

The number of biofeedback devices has exploded over the last several years, allowing athletes to acquire and interpret loads of data with the goal of maximizing their potential. A company called BSX Insight recently launched the first wearable lactate threshold sensor that looks inside your muscles to track lactate levels. Before the launch of this product, the only way to measure lactate levels was to have blood drawn and analyzed during a treadmill or stationary bike workout, with a price tag of around several hundred dollars per test.

The Benefits

While power meters and heart rate monitors offer immediate feedback, knowing your lactate threshold offers greater insight into what your body is capable of, allowing greater customization of your workouts and training plans. Simply stated, your lactate threshold is the point at which your body produces lactate faster than it can remove it.

When To Use It

The BSX Insight sensor isn’t something you’d wear on a daily basis. It’s a tool designed to use every four to six weeks to measure improvement and tailor your training. The engineers behind the product wanted the system to do more than spit out numbers, which is why they created a platform that allows you to track, store and share your data while creating a customized training plan through the company’s website.

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How It Works

The sensor itself is about the size of a large key fob and slips into a calf sleeve. LED lights shine through your skin and can measure lactate levels in your blood with tremendous accuracy on par with results you’d get in a lab test. There are three versions designed specifically for runners, cyclists and triathletes. The device is ANT+ compatible and can sync with an app on your phone but can’t pair with any cycling computers or watches. You have to train with a power meter while cycling and a heart rate monitor in order to get a clear picture of your lactate threshold.

The Deal

With a price ranging between $300 (running only model) and $420 (for both cycling and running), this product is an investment, especially for those who’ve already dropped hundreds of dollars on a power meter. Performing a functional threshold power (FTP) test can yield similar target training zones, but for serious athletes seeking the most accurate information possible, the BSX Insight could be a valuable tool. It certainly makes the traditional method of drawing blood seem as archaic as measuring your heart rate by feeling for your pulse and counting.

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