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Development Team Member
Posts: 2
Here is a repost from our blog at by one of our elite women racers, Dana Stryk.  We have been testing the Moxy on her within our studio for the last three weeks.  We would love to hear your comments.



                                                                                                                 Dana M. Stryk
A few weeks ago we added a new gadget to the list of data gathering devices, a Moxy Monitor (MM), which measures muscle oxygen saturation levels. This device is about the size of 1.5 packets of artificial sweetener and 0.82 inch thick. You place the MM on the center of the vastus lateralis, halfway between the greater trochanter and medial condyle. As the amount of oxygen in the hemoglobin changes, the color of the hemoglobin also changes. Using near-infrared light, the MM reads the color of the hemoglobin, translating this data into a percentage of muscle oxygenation, SmO2. I will leave anything more than this very basic explanation to the scientists, so visit the website to learn more.
We use PerfPro software to run all of our computrainer videos and the MM data can be transmitted real-time to this program and displayed with the other data such as Power Zones, Watts, heart rate (if I used a monitor) and so on. One of the statistics generated is Percentage of SmO2. Please keep in mind that I am an dismal scientist (i.e. economist) and the last time I had a biology class was in high school, so my impressions of the usefulness and any meaning of these numbers is based on cardiac knowledge rather than scientific theory (cardiac knowledge = what I know deep in my heart is true but have no proof).
My research questions:
  1. What type of warm-up would be most beneficial? I think I need a long warm-up before my legs are ready for hard efforts. The warm-up prior to racing is something that I tend to minimize for several reasons. Could these numbers prove my inner "you really should warm up on the trainer and stop socializing" voice correct? 
  2. Do I notice a correlation between watts and %SmO2? 
  3. Will the data from MM suggest that I should have skipped graduate school and pursued a professional cycling career (ignoring the fact that I did not ride a bike at that time in my life)? 
Field Research:
Nasty weather and my outside temperature restrictions (below 40F?? on the computrainer!) relegated me to an indoor trainer. Luckily, we have a computrainer spin studio in the garage, with almost every Sufferfest video and many ErgVideos in our library. From tempo to VO2 max efforts, a video exists to create pain, suffering and a great deal of sweat. All data comes from these indoor rides, which lasted between 45 and 180 minutes.
The MM sits on the centerpoint of one of the quad muscles, with the elasticity of your bib shorts holding it in place since the neoprene strap which comes with the MM is too annoying to wear when cycling. With the shorter length of many women's bib shorts, it is difficult to keep the MM in place. It moves toward the hip and toward the side of the leg when pedaling. Due to my preference for having skin, I ignored a suggestion from my training partners to use duct tape to secure it in place.
MM impressions:
  1. My legs need much longer than I normally give them to warm-up. During the week, my legs usually feel tired or dead when I first get on the bike. My %SmO2 for these workouts began in the 40-50% range, decline a bit and then started to increase after about 10 minutes. My rating of perceived exertion also fell, despite an increase in my actual exertion (measure by watts).  Warming up for me is more important than I realized.  I reflect back on a couple of races last summer when it was too hot to warm-up, so I did not and wondered why I really wanted to die for the first twenty minutes when others who also did a minimal warm-up seemed fine.  The MM data shows the importance of increasing hemoglobin and oxygenation prior to the start of my races. 
  2. Inverse relationship between watts and % SmO2 once warmed-up, as expected. Higher values of %SmO2 indicate more recovery and I noticed these numbers increasing during recovery between intervals. 
  3. The value returned for %SmO2 strongly depends on the placement of the MM on the vastus lateralis. For example, I placed the MM on the center point (between the head of the femur and the medial condyle) of this muscle, on the estimated midway point. It moves. When it moves, the %SmO2 number changes. From my experience, it appears that moving the MM toward the hip increases the %SmO2 value and moving it toward the abductor decreases the value. The movement needed to generate these changes is small, about 3-4 mm. 
  4. If higher %SmO2 values correlate to greater recovery, my legs recover quickly between intervals. This correlation indicates that my excuses of...."my legs were fried and I just needed to sit in" holds for a brief period of time but....indicates the needed ability to just "embrace the suck" so to speak. 
Overall assessment:

The jury is still out. The MM data will help craft an efficient warm-up for the different races we do. The more data we gather, the better, with the hope of understanding the relationship between these values and data from the power meter.
Oh, sadly, my choice of graduate school over attempted employment within the pro peloton was probably the correct one.
Juerg Feldmann

Fortiori Design LLC
Posts: 1,530
This  is a very nice  initial  information  from a very open minded  person.
  As  in any  new  tools  , we have to  be  somewhat  patient , when looking on the  numbers.
  Some great point are made.
  1.  Always  fix the MOXY ( nearly no matter where)  it just has to be  stable during an assessment and or workout.
.  2.  Always , when looking  at the information look  at the trend first  rather than  on   absolute numbers.
 Physiological information's  are  what they are  physiological information's. They  can change  as   certain situation may change (  Temperature  change )  hydration change,  nutritional change  blood sugar  trends, )  position change in the sport.    and many more factores.  This  is what separates  a    car  form a human system.
  " Inverse relationship between watts and % SmO2 once warmed-up, as expected. Higher values of %SmO2 indicate more recovery and I noticed these numbers increasing during recovery between intervals.

 Be  when starting out with MOXY  careful   and make a difference  between  observation  ( what  do you see )  and interpretation ( what  do you think ).
 The above  statement is  what Kyle   saw  as he  made is  initial use  with MOXY. But that's; it. SmO2   as it stands  is  simply the %  of  Hb loaded    in comparison  to the total Hb   in the tested  area.
  This is  foremost w what we test.
 Similar  as a  350 watt performance seen on a wattage  meter means  just that   350 wattage pushed  at that  specific situation, when I observed  the wattage meter.
  It does not tell you any thing more.
  We  do not know  who and how I  contributed   to this result.  at all.
 I need some additional information   on how  I reached  350 wattage.
 Same is true  for  SmO2.
  I need  the overall  physiological picture.
.An increase in SmO2  can    hint, that you  load more O2  than you need.
   so a  "positive " feedback on the energy balance.
  But an increase in SmO2  can as well mean  , that I increase the  amount of  O2  on the  availabel Hb  with loading O2  on it  , but I may  not be able to use  it  due to  problem  with Bio availability .( O2  Diss curve shift  )
  So in fact I may  actually  get less O2  in,  but as I not  can unload the Hb  it  appears as if  I  have more  O2 than before.  I actually have more  O2  but not because I deliver more ,  but I  use less  because I  can't use it.
 What sound  confusing is one  of the great benefits  of  MOXY as it tells us  much more than  a number it tells us  what is going on physiologically   and why I may stop  a workout despite  80 %  SmO2  values  and why I can keep going a workout   despite  a  40 %  SmO2  value.
 It is a very different way of looking at performance. Instead of using %  of  some  maximal  values  we use  our bodies feedback to understand  what limits  performance  and what enhances performance. Limiter and compensator.

 We just need  to have the ability  to look somewhat outside the indoctrinated  " classical" ideas we are used  to work  with  and still get confused to work with.
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