Product Review – BSXinsight Wearable Lactate Threshold Sensor


As cyclists, we are always looking for ways to improve our training and performance, and there is no shortage of ways to monitor and test our improvements on the bike. There is no argument that the most highly regarded tests to gauge a cyclist’s fitness and performance have to be a heart-rate monitor, a VO2max test, and the evasive lactate test. Ask anyone who has had a lactate test, and they will all tell you that although the results of the test were useful, the test itself was a pain (prick) in the ass (finger). So BSXinsight decided to bring cyclists the same exceptional test results without all the finger pricks.

At Interbike 2014, I had the opportunity to have a lactate test using the BSXinsight non-invasive (read “No More Finger Pricks”) system. This small wearable device is able to analyze changes in your exercising muscle to immediately identify lactate threshold. It is attached around your calf in a compression sleeve that comfortably slides on.

My first concern was, how can something that is attached outside the body, never to see a drop of blood, actually be accurate? But after thirty minutes of testing and product explanation, the accuracy was no longer in question. The BSXinsight test was 99.9% accurate to the blood prick test that was done at the same time.

So let’s describe how it works. BSXinsight uses revolutionary technology that allows the monitor to see inside your muscle, measuring your lactate threshold and generating personalized training zones. Using LED lights to “look” into your muscle, BSXinsight analyzes your unique biosignals to identify both your lactate threshold and personalized training zones. It uses the same technology that experts and clinics use – with the added benefits of being wearable, ANT+ compatible and immediately actionable. And the results are almost instantly available when the test is completed.

I can say that I was completely blown away by how easy it was to use, and how accurate the results were. Without a doubt, the BSXinsight will change not only how lactate thresholds are calculated, but also who will be able to administer the test. With a projected retail price point under $370.00, it is within budget for every cyclist looking for cutting edge technology. The BSXinsight will give them the ability to test their lactate threshold regularly so that they will always know if their training is working or not. Trust us when we say your coach will love that you can supply him these data on a regular basis. Stop trying to “feel” whether you’re pushing too hard or leaving too much in the tank and let the BSXinsight tell you what your body is trying to say about the effects of your training.

The image below basically shows how the sensor interacts with your body to determine how much lactic acid is in your blood.

The following test results (mine) also offer some description of how the test works.
blood test

BSXinsight uses the same heuristics for identifying LT (Lactate Threshold) as physiologists at other top performance centers such as CTS. Put simply, we look for two 1mmol increases over subsequent stages. As you can see, this happened at the 200 watt stage for you which was interestingly well above the 6mmol average published in most of the literature.

After cleaning up the data from noise artifact we then conduct two levels of data processing to identify important physiologic events within the data signal.

Next, after the aforementioned processing/data cleanup, BSX algorithms take the composite profile plus integral physiologic events to identify your lactate threshold. (shown below)

The top graph represents the final stage of your exercise and I have labeled the power at each stage for you for easy reference. The black line on the bottom graph represents the blood lactate LT that we discussed at first. The apex of the histogram in the middle graph represents BSXinsight’s optical LT determination.

As you’ll appreciate, both the blood and optical determination occur at the same stage, 200 Watts. As you’ll also appreciate, there is an offset between the blood and optical determination of a short period of time. This is due to the increased resolution that BSXinsight has over blood lactate techniques which only collect data every 3 min. Hence BSXinsight’s real time measurement identifies the event even quicker than blood methods without sacrificing accuracy.



To purchase the BXSinsight please check the website in December

For more info go to BSXinsight