Metabolic Efficiency – Gas Exhange Test Issue

  • Creator
  • #36527

    I took my first gas exchange test today using the Uphill Athlete protocol. My testers were having me use the PNOE portable tool, which I was told features a fairly comfortable face mask to take the gas measurements. During the warm up I did not use the mask. I started the warm up at a 2 mph pace and 10% incline and slowly increased it to 6 mph, where I felt relatively comfortable running.

    When I started the test and put the gas exchange mask on I found the mask to be very uncomfortable and it became very challenging to breath (it almost felt like I was training at elevation). In my warm up (not wearing the mask), I could comfortably run at a 6 mph pace at 10% incline; however, during the actual test, while I was wearing the mask my HR was approaching 190 at a 6 mph/10% incline pace and I felt like I was doing a very hard crossfit-type interval workout! I got off the treadmill and was totally out of breath after only 20 minutes. I started the test at a walking pace of 4 mph, and increased it at .4 mph/3 minutes. I would normally consider this to be very easy on a treadmill, but during the actual test, while I was wearing the mask, the entire workout felt very hard.

    Is there some sort of learning curve associated with using the mask? My testers said it might just be because I need to spend some more time training with a mask on (they let me borrow their mask to go on a run with and are going to come back to test me again). Wondering if anybody else has had this experience where having the gas exchange mask significantly affects their performance during the test and if there is anything that can be done to get adapted to using it so I can get a better measurement.


  • Inactive
    Anonymous on #36533

    That does seem like a big difference in intensity. Wearing the masks is never ideal, but I never had any issues except near the end, but I suspect mine were psychological/claustrophobic.

    Anonymous on #36555


    This fall I was sent a PNOE system by a company that wanted UA to begin to use the PNOE and recommend it to our users. I tested myself over 10 times. I tested 3 of our other coaches as well 2-3 times each. Every one of us felt that the mask was very restrictive in terms of airflow. As Scott Semple says, however there is a psychological/claustrophobic component to this perception but I never felt comfortable using it. However there were a number of other issues with calibration and user interface that made me reject the PNOE as a practical tool for the inexperienced user.

    Your experience showing the massive jump in relative perceived effort between warm up and test tells you right away that regardless of whether this was due to claustrophobia or to actual restriction of airflow your test could not reflect your actual metabolic state.


    shalinpatel00 on #36625

    Thanks Guys. That is very interesting that all of the other coaches thought the mask was very restrictive. My testers assured me that I was the only person that thought this about the mask. Do either of you have a preferred piece of testing equipment that has given you the most accurate results? I will try to look for a lab that has that.

    shalinpatel00 on #36641

    Has anybody tried the New Leaf systems? Any thoughts on those?


    Anonymous on #36682

    I do all my testing via lactate with only very rare gas exchange tests out of curiosity. For the price of two lab tests you can buy your own lactate meter. After that, the cost of each test depends on how many strips you use.

Viewing 5 replies - 1 through 5 (of 5 total)
  • The forum ‘General Training Discussion’ is closed to new topics and replies.