Sign up Latest Topics

  Author   Comment  

Development Team Member
Posts: 1

As students in Dr. Bodary’s Exercise Technology class at the University of Michigan, we are thrilled to have the opportunity to work with several innovative, groundbreaking technologies that have the potential to change the way both elite athletes and the general population approach exercise. The three of us, Grace, Josh and Ryan, are fortunate to be working with the MOXY Monitor to analyze tissue deoxygenation and reoxygenation during sets of resistance exercise followed by varying types of “rest”. We are excited to speak with you all, so we may be able to share our experience with you, and hope that you will be able to assist us where we may have points of confusion.

Literature shows that different time and modalities of rest following resistance training have different effects on tissue oxygenation. In strength training protocols of similar total repetition volume and identical loading, rest intervals of 15 seconds show significantly greater tissue oxygen depletion compared to 2.5-minute rest intervals (Penzer et al., 2016).  Additionally, blood lactate clearance is shown to be significantly improved when using exercise-based recovery compared to massage-based and simple rest recovery (Martin et al., 1998). Physiologically speaking, light aerobic can divert the lactate that builds up during anaerobic exercise into more “useful” processes of energy production, thereby assisting in recovery, but the balance between the intensity of this aerobic exercise and performance on subsequent resistance exercise sets is unclear. Further research into the impact of intra-workout recovery techniques on subsequent exercise sets is vital for coaches and athletes that want to achieve peak performance during and derive the most benefit from their strength and conditioning protocol. It is our intent to use the MOXY Monitor to track muscle-oxygenation levels in the vastus lateralis muscle of the quadriceps during resistance exercise to explore this issue.

Three subjects will perform five sets of five back squats at 75% of a one-repetition max (1RM) with a tempo at 2sec down-1sec pause -1sec up-1sec pause. Following each work set, the subjects will rest for 3 minutes by one of three modalities, 1) sedentary rest, 2) light aerobic rest, and 3) aerobic rest. The subjects will then participate in a sixth set of back squats at 75%1RM and will do as many reps as possible until volitional failure. We will use this set as a measure of “performance”. The MOXY monitor will be attached to the vastus lateralis throughout the entire data collection period. In sedentary rest subjects will sit; light aerobic rest will consist of walking at a self-selected pace, and aerobic will consist of light biking at 30% of individual maximum revolutions-per-minute (RPM). The experiment will be conducted during 3 separate test days, and the individuals will be randomized into the order in which the rest modalities proceed. 

We expect to learn a great deal about rest modalities and their effect on tissue reoxygenation during rest and tissue deoxygenation during exercise. Based on previous research, we hypothesize that light aerobic rest periods will result in the greatest rate of tissue reoxygenation of the vastus lateralis after squatting, and optimum performance. However, we do foresee challenges. One challenge is determining if the vastus lateralis is the best location for the MOXY monitor, as different individuals likely incorporate different patterns of muscle activation based on differences in body mechanics and squat technique.  A second challenge is appropriately addressing any differences we may discover between male and female results. Lastly, we would like to know how MOXY is intended to be used with resistance trained and power-based athletes, and if our study can be modified in any way to provide better insight into that question.

We anxiously await any answers or opinions you may contribute to our project. We also hope that you will not hesitate to ask any questions you may have for us about the project, and all suggestions for ways we can improve our project are welcomed. The prospect of using MOXY to improve exercise of individuals outside of the traditional “endurance exercise” sphere, by extending it to recovery of resistance athletes, is exciting, and we hope that you will share this excitement as well.



Martin NA, Zoeller RF, Robertson RJ, Lephart SM (1998) The comparative effects of                  sports massage, active recovery, and rest in promoting blood lactate clearance                      after supramaximal leg exercise. J Athl Train. 33:30-35

Penzer F, Cabrol A, Saudry S, Duchateau J (2016) Comparison of muscle activity and              tissue             oxygenation during strength training protocols that differ by their                                 organisation , rest interval between sets, and volume. Eur J Appl Physiol.                                    116:1795-1806



Development Team Member
Posts: 227

Fascinating research and I’m very interested about the outcome.


I will share my own unscientific observations from cycling. I have 2 Moxy sensors, one is always on Deltoid and second on following leg muscles: VL, VM, BF, RF.


During rests one minute and longer, I noticed complete stop always provides more oxygen to my muscles. Engaged muscle is always oxygenated first, then Deltoid. At about 70% of working muscle peak smo2, I can see Deltoid Smo2 increasing, those numbers depend on intensity, but trend is generally the same.


The only difference from above I see at intervals at high loads (120% of 60min power and above) and short 20-30s rests, Example: I’m cycling at 360W for one minute and suddenly stop, in many cases, but not all, my Smo2 will go down for first 10s before actually shooting up, I believe this could be related to higher muscle compression. If I keep soft pedaling my smo2 will not decrease, it will keep steady for 5-10 sec then will start to slowly increase.


Generally I always use to soft pedal during races, explanation provided to me was to “flush the legs”, but this season I’m going to change that and actually fully rest (stop spinning). I think in endurance full stop will give me advantage.


It would be interesting to see different level of utilization\engagement of leg muscles during the same exercise. Before the main experiment, you could place Moxy on different muscles on each subject (VL,RF,VM) and ask them to perform the same back squat set and see difference between subjects, are all using VL at the same level when comparing to eg VM or RF? I found in cycling differences are very common. This will revel utilization level, which could be different from subject to subject and caused by foot position change etc.


Development Team Member
Posts: 1,501
I will j hopefully be back in the weekend on this  fascinating topic  to give  you some 15 years back ground  on what we did  and do.
 Seboo makes some great observation and the explanation what happens   and why  we see what he observed is on the forum explained in different  sections and how we  can back it up.

Development Team Member
Posts: 264
Hi rzayance and welcome to the forum.
If I understood correctly you will have 5 set, each consisting of 25 seconds of "heavy" load followed by 3 minutes of rest (different conditions).
I am quite sure you see will a deep deoxygenation on the load phase, then a fast recovery with an overshoot and then depending on the type of "rest" a different trend.
I would expect a larger overshoot with a full rest but also a faster kinetic to come back to the initial value and the delivery system will also come back to the resting values.
With some light activity, the oxygenation maybe kept at higher values (compared to full rest) and so the delivery system.
At the next load, I would expect a deeper deoxygenation level for the full rest case.
And at the end, I would go for the aerobic rest to win the game.
Looking forward to see the results

Development Team Member
Posts: 1,501
Short question:
 Why would  I  be happy if  we can promote lactate clearance. Why would you like to clear out lactate ?
And  the  answer  may explain why we have a lower lactate level after  activity than after massage  and after a passive recovery. look at the discussion of   using "preload' race or workout ideas.
 Preload  can as well be  pre empty.
 Hints . O2  disscurve  shift prior  to  certain activities.
 Preload lactate  prior  to certain activities.
 Pre load plasma  volume  for  certain  more in depth  stimulation  and many more  steps we  can do prior to a  target stimulation to increase the effect.

Development Team Member
Posts: 217
I'm just thinking out loud and sharing ideas [smile]

I was wondering, if it would better to simplify the test protocol, so to target the leg muscles only(leg extension or seated leg press)... it might yield a more repeatable result.  
A back squat is a very advanced move, it requires a good core stability and movement coordination which could eventually affect the repeatability of the move more if a subject was "unfit for it".

Also, it is important to control the recovery protocol too? maybe using an ergometer bike where you can maintain a consistent recovery load (Watt) between sets. 

Or can we use moxy to determine an ideal Ergometer load level live?

with reference to Juerg question:
Why would  I  be happy if  we can promote lactate clearance. Why would you like to clear out lactate? 

So lactate eventually converts back to glycogen by the kidney&liver,  the heart muscle and the brain is able to convert lactate to fuel directly.

High level of lactate reduces the blood pH level, which can shift the discursive more to the right making the unloading of O2 in the muscle more efficient.  

 So preloading lactate before a workout would desaturate SmO2 rapidly  but during rest period we may have a smO2 recovery delay due to disscurve shifted to the right.     

Would the respiratory system be working overtime to balance pH & CO2?   


Development Team Member
Posts: 1,501
 I was wondering, if it would better to simplify the test protocol, so to target the leg muscles only(leg extension or seated leg press)... it might yield a more repeatable result.  
A back squat is a very advanced move, it requires a good core stability and movement coordination which could eventually affect the repeatability of the move more if a subject was "unfit for it". 

There are immense  problems when we start with  complex  motions  and  minimal ideas in what NIRS  can or not  can do.
. Complex motions  have the  risk, that by  the same load in physical terms  we have a  very different response during the load and even more complex in the recovery  sections.
, whether we  have a  respiratory , cardiac  or muscular limitation . ( not even yet  stating by a  coordination problems  of  the   muscle  disbalance and or dysharmonie..
 Using the tools  suggested here   will open some very intriguing theoretical ideas, but in many cases  miss the practical facts.
 It is now  close  to 20 years back  when Herb and I   started a   grade 11 / 12 high school program  where  we  had  the  same idea  and plan  as  discussed here. To  actual  give us  some decent  facts  and avoid theoretical ideas we used the below physiological toys.
  Below  the basic  physiological needed  tool  box for   small research projects.
ecgm equi 2.jpg 

The  nicer  tool  toy box is  below and that is what we use depending on the  questions we see. 

ECGM  equiment.jpg

ll this  tools  have very  nice  feedbakcs  and if  combined  can add a lot more to our  current understanding. If  you have questions on why we use some of them  please come back and ask.

The original   idea  or  hope was, that we  can find  easy to use  portable  tools  to get feedback on the  below  physiological feedbacks  


hese are  pics  from  our  high school  script  and below a  pic  from a real live feedback  with these tools . 

Flurin equipment.jpg 

So great to see this   group   looking  at   what we use  now since many years  and  this will help  at least us  for sure  to see , why we in many  cases use  very different approaches,  than what the classical  training idea  would suggest.
  Why for  example the same  strength training idea   will end up  with a very different end result  when we   have an AC:L  rehab verusus  a meniscus  rehab. IN both cas  we may  train the  quadriceps  and  we end up  with the same load program with a different outcome. Or  why  when we sue  60 %  for example of a  VO2  max  in 2  different atelets  we  end up with  aa different end result  despite the  " same "  %  load. Or  we   have a  15  second load  and a  30 second  rest and 5  reps  and  5   students  and we  end up  with  different  end results  even  all use  70 %  of  1 Max Rep  weight ?????  The future  will be in physiological guided  workouts  on a very individual base  and NIRS is one    tool  who  can be used  to  look  at closer to the future  approach.
  This  idea  starts  to get more traction  which is nice  to see.

James G Hopker 1*and Louis Passfield 1


Prescribing training involves the manipulation of intensity, duration and frequency of the sessions to improve cycling performance. As sports scientists our ideal is to help provide an objective scientific basis for this training prescription. But whilst we have developed an intimate knowledge of training adaptations and their regulating molecular signals (Stepto et al., 2009), we do not appear to be moving closer to providing a scientific basis from which to design effective training programmes (Borreson and Lambert, 2009).

 Below we post 3 questions for future training related research studies to consider.


 1) Are training studies using appropriate indices for specifying training intensity?


 2) Should training studies take more account of individual variation?


 3) Are training studies examining the right question?


There appears to be increasing agreement that the response to a standardised training programme can be remarkably diverse (Mann et al., 2014).

 This has lead some to examine these training “responders” and “non-responders” and its genetic basis (Ehlert et al. 2013). Surprisingly, the alternative hypothesis that training has not been standardised appropriately appears to have been little considered (Mann et al. 2014).

From this perspective the issue becomes not whether a cyclist is a responder or a non-responder, but rather what is his or her optimal training intensity.

For example, it has long been established that cyclists’ time to exhaustion at the same relative intensity can vary hugely. Coyle et al. (1988) found that at 88% VO2max cyclists’ time to exhaustion varied from 12 min to 75 min. However, the method for prescribing training in most studies remains standardised as a percentage of maximum.

Consequently, it seems unsurprising that the training response differs between two cyclists training at a standardised intensity that yields such a diverse response to even a single bout of exercise.

Even where the ability to sustain a standardised training intensity is more carefully controlled, the underlying assumption that this is linked to a training response remains unproven.

Previous Topic | Next Topic

Quick Navigation:

Easily create a Forum Website with Website Toolbox.

HTML hit counter -