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US company to launch wearable lactate threshold sensor + video

Gamechanging BSX Insight sensor achieves Kickstarter target and is scheduled for release later in the year

A project to bring ‘the world’s first wearable lactate threshold sensor’ to market has achieved more than double the funding it was seeking on Kickstarter. The BSX Insight sensor pairs with a sports watch to provide your heart rate, cadence, pace and calories burnt too.

The BSX Insight was designed and developed by endurance athletes Dustin Freckleton and Nithin Rajan who met at the University of Texas in Houston. If it delivers on its promises, this could be a valuable training and racing tool.

“Lactate Threshold is one of the most common, and THE most effective, performance marker used by competitive coaches and athletes,” says BSX Insight. “For over 50 years it has been the gold standard for performance measurement and has repetitively been shown to be over 95% accurate at predicting race finish order. This means it can be used with near perfect accuracy to personalize the appropriate training intensities of each athlete.”

There’s a big debate about the exact role of lactic acid in exercise, but once it starts to build up in your body you’re on a slippery slope. That’s why it’s such a crucial measurement in endurance sports. Go beyond your lactate threshold and you’re exercising at an intensity that isn’t sustainable for a long period.

“When lactic acid starts to build up in the body it does so very dramatically and very quickly,” says BSX Insight.

“This event is known as lactate threshold and it signals a state of imbalance—when the body is starting to depend on less efficient energy sources. Exercise intensities at this level can only be maintained for a short period of time before fatigue and exhaustion occurs.

“Since fatigue and exhaustion are never the goal of an endurance athlete, lactate threshold is an important event to both know and train for.”

That all sounds fair enough, but how the hell do BSX Insight measure your lactate threshold through a wearable sensor?

“The primary sensor is comprised of an LED array that passes light through the muscle belly of the gastrocnemius (also known as the calf muscle), and a detector,” says BSX Insight.

“As the light passes through the muscle tissue, it is reshaped by elements within the tissue (known as chromatophors) to produce a unique signal (similar to a fingerprint) that contains information about the local metabolic activity.

“This profile is then processed by embedded BSX algorithms to analyse identifiable signal features which exist within the profile. When combined together, these are used to accurately generate a lactate threshold curve. Real-time monitoring of this curve allows the athlete to always know where they are along that curve and their proximity to crucial training thresholds.”

If it works as BSX Insight claim, this sounds like an incredibly valuable training tool. If you train by heart rate, for example, you might work to training zones based on a percentage of your maximum heart rate (you might have determined your zones more accurately by other means). Your lactate threshold is usually estimated at between 80% and 90% of max in trained endurance athletes.

The key word there is ‘estimated’. An accurate lactate threshold monitor would take the guesswork out of it. You can move your lactate threshold by training effectively. Essentially, the higher you can raise your lactate threshold, the faster you can race (yes, plenty of other factors come into it too, and the importance of those factors vary between events).

Potentially, the BSX Insight could help you train more effectively and race at your maximum sustainable intensity. It’s a lot like a power meter in that respect (there’s a whole conversation to be had there on the pros and cons of each).

You can, of course, get your lactate threshold measured in the lab, but it’s a pretty expensive and time consuming business. Plus, the advantage of the BSX Insight system is that you get constant feedback as you’re exercising.

The monitor snaps into a compression sleeve that you wear on your calf, and you pair it to a sports watch using ANT+ or Bluetooth. It can give you audio/visual alerts to speed up or slow down.

At the end of your activity you can wirelessly upload the data and check it out on BSX’s web-based software (trainBSX)

The BSX Insight Kickstarter campaign received $121,897 of pledges, more than doubling its $50,000 target. BSX says that this will enable the brand to take its prototypes to full-scale manufacture, complete the software to enable the BSX Insight to communicate with sports watches and other wearable devices (currently it works with only Garmin), integrate with social and training platforms like Strava, Facebook and Twitter, and to miniaturise the design.

BSX aim to begin manufacturing in September and deliver the Insight in the final quarter of this year.

The BSX Insight will be available in a Runner’s Edition ($249 with six months’ trainBSX premium access), a Multi Sport Edition (with both cycling and running profiles, $329 with six months’ trainBSX premium access) and in a Team Edition (for multiple users).

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Mat has been in cycling media since 1996, on titles including BikeRadar, Total Bike, Total Mountain Bike, What Mountain Bike and Mountain Biking UK, and he has been editor of 220 Triathlon and Cycling Plus. Mat has been technical editor for over a decade, testing bikes, fettling the latest kit, and trying out the most up-to-the-minute clothing. We send him off around the world to get all the news from launches and shows too. He has won his category in Ironman UK 70.3 and finished on the podium in both marathons he has run. Mat is a Cambridge graduate who did a post-grad in magazine journalism, and he is a winner of the Cycling Media Award for Specialist Online Writer. Now over 50, he's riding road and gravel bikes most days for fun and fitness rather than training for competitions.

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