I'm guessing just software as it wouldn't make sense for them to modify their hardware/production process. Frankly, until you mentioned it, I wasn't aware that there were different models. When I backed them, it was touted as being able to monitor LT for biking, running... and I think swimming as well. 90% sure on the swimming thing.

For me, I'm just curious to use it for establishing my training zones for cycling. I'm curious to see how those established zones vary from pure power-based training.

The sleeve doesn't actually measure the levels. The BSXinsight device that goes into the custom sleeve does.

Andrew,

Thank you for the note and for the continued following of BSX Athletics.
To answer your question:
Yes, the BSXinsight device uses NIRS to measure the O2 amongst other analytes in the muscle tissue to infer the LT. We use a patent pending algorithm to analyse changes in concentration in the analytes in order to predict the accumulation of lactate in the muscle, which precedes a systemic rise in lactate.

For a more in depth answer go HERE

I realize this is going to bring about a bunch of questions from the rest. Please see my post above that contains the video link as well as brochure link.

Bryan
BSX Athletics

Good morning everyone. My name is Bryan Kraham with BSX Athletics.

I will do my best to answer your questions.

Difference between running, cycling and multisport models - The quick answer, biology and technology. The longer answer: The multi-sport edition basically doubles the functionality providing you with both LT profiles. As Jonathan Caron will tell you, you have two different zone set ups for running and cycling. Example: the top of my zone 2 is 155 for running and 151 for cycling. The other differences are pairing peripherals to your different devices. Example: you have a power meter for cycling but not running.

Jonathan, you are correct in your assumption that you can get data from field tests, but I wouldn't call them very accurate. Many things can effect the test: wind, temperature, elevation, did the athlete consume caffeine. I did the field tests for both running and cycling and then I took a proper LT test. my zones were off by about 6-7 beats per zone (my coach uses a 4 zone system for me), and as you can attest, this is not very accurate. I did these on a treadmill and a stationary trainer to take out the variables mentioned above.

For the price of about one Lt test in the lab, you can use the BSXinsight as a bench marking tool every 6 weeks to track your fitness and adjust your zones.

Bryan

I was under the impression that you were simply inferring LT from changes in muscle O2 content (measured using NIRS)? Is that not the case?

(As for the notion that quantifying training load/intensity based on physiological strain is superior compared to doing so by measuring the applied stress, consider the following:

http://www.ncbi.nlm.nih.gov/pubmed/24104194

http://www.ncbi.nlm.nih.gov/pubmed/24662229)

Thanks for coming into the discussion, Bryan. I'm curious if you have looked into whether there is much utility for real time LT data during exercise. This would need more support from Ant+ headset companies, but it seems like it ought to be possible with the device if I'm not mistaken. Is this something you have looked into?

Bryan, have you done comparisons between the lactate profile predicted by the BSXInsight versus measuring lactate levels in the blood during the same test? I would be very interested in seeing the results for various athletes/tests. I definitely like the idea of the BSXInsight but would want to be convinced that the accuracy is good enough to replace the lab testing that I do every few months. The potential cost and convenience benefits are huge. Somehow, however, I don't think my coach who has significant money invested in lab equipment, is going to appreciate me showing up to one of my tests with a BSXInsight to do my own comparison. :-)

Thanks for the quick reply. I'm mostly just curious about the principles involved, because understanding those might be helpful in understanding/predicting "edge cases" where things break down.

(E.g., I have a colleague who is studying children with Barth's syndrome. Their muscle O2 content actually *increases* markedly with increasing exercise intensity, which I have hypothesized is due to a hyperkinetic circulation as found in other neuromuscular diseases, e.g., McArdle's disease. Obviously this is neither a normal response nor your target market, but if lactate concentrations are only being estimated based on oxygenation, your device wouldn't work as intended. OTOH, if you were measuring lactate based on its spectral characteristics, it still might.)

Bryan, have you done comparisons between the lactate profile predicted by the BSXInsight versus measuring lactate levels in the blood during the same test? I would be very interested in seeing the results for various athletes/tests. I definitely like the idea of the BSXInsight but would want to be convinced that the accuracy is good enough to replace the lab testing that I do every few months. The potential cost and convenience benefits are huge. Somehow, however, I don't think my coach who has significant money invested in lab equipment, is going to appreciate me showing up to one of my tests with a BSXInsight to do my own comparison. :-)

I don't think it should be a question of which works best but a question of can we learn anything by quantifying both.