Sign up Latest Topics

  Author   Comment  

Development Team Member
Posts: 1,501
I  am getting an increased amount of  emails  form  specific  groups  with the question of validation on the discussion we have  that MOXY. NIRS   or e better  SmO2  can be  sued   as a recovery  indirect feedback on   Cr.P.

 SmO2   can be used  a s a feedback on  Cr.P  recovery  but we use often as well the tHb  trend   to  increase the  recovery   feedback  not just on metabolic  or energy substrate but as well as a part of  delivery feedback.  It is  fascinating  for me to see with  how much skepticism  ( healthy skepticism )  NIRS./ MOXY  is  looked upon as we have finally a direct feedback on energy  delivery  and utilization. In contrast to  the   earlier used lactate, where we have in the best case scenario  a  trend  with some  speculation. LT  was never  under that much scrutiny  and that's was good as it never  woudl have been used  for what it is used   now  in many  centers.
 Now here a  fun article  and how   great the scientific  back up is   when using NIRS/ MOXY.

A cross-validation of near-infrared spectroscopy measurements of skeletal muscle oxidative capacity with phosphorus magnetic resonance spectroscopy

Terence E. Ryan, W. Michael Southern, Mary Ann Reynolds, and Kevin K. McCully

Author information ► Article notes ► Copyright and License information ►

This article has been cited by other articles in PMC.

Go to:


The purpose of this study was to cross-validate measurements of skeletal muscle oxidative capacity made with near-infrared spectroscopy (NIRS) measurements to those made with phosphorus magnetic resonance spectroscopy (31P-MRS). Sixteen young (age = 22.5 ± 3.0 yr), healthy individuals were tested with both 31P-MRS and NIRS during a single testing session. The recovery rate of phosphocreatine was measured inside the bore of a 3-Tesla MRI scanner, after short-duration (10 s) plantar flexion exercise as an index of skeletal muscle oxidative capacity. Using NIRS, the recovery rate of muscle oxygen consumption was also measured using repeated, transient arterial occlusions outside the MRI scanner, after short-duration (10 s) plantar flexion exercise as another index of skeletal muscle oxidative capacity. The average recovery time constant was 31.5 ± 8.5 s for phosphocreatine and 31.5 ± 8.9 s for muscle oxygen consumption for all participants (P = 0.709). 31P-MRS time constants correlated well with NIRS time constants for both channel 1 (Pearson's r = 0.88, P < 0.0001) and channel 2 (Pearson's r = 0.95, P < 0.0001). Furthermore, both 31P-MRS and NIRS exhibit good repeatability between trials (coefficient of variation = 8.1, 6.9, and 7.9% for NIRS channel 1, NIRS channel 2, and 31P-MRS, respectively). The good agreement between NIRS and 31P-MRS indexes of skeletal muscle oxidative capacity suggest that NIRS is a valid method for assessing mitochondrial function, and that direct comparisons between NIRS and 31P-MRS measurements may be possible.

Keywords: mitochondrial capacity, 31P-MRS, oxidative metabolism, mitochondrial function



Development Team Member
Posts: 1
Thank you very much for providing the Ryan et al. (2013) abstract regarding NIRS recovery post-exercise. Our research group has started investigating NIRS recovery using the Moxy system. I noticed in the Ryan et al. (2013) article that the investigators used an intermittent cuffing procedure during the recovery to help model the NIRS recovery response.

As we would like to help make our research as practical as possible for coaches/practitioners, I was wondering when the Moxy community members assess the NIRS recovery response post-exercise:

1) What types of analysis techniques do you use (e.g., visual inspection; NIRS values at specific time intervals - 1 min, 2 min 3 min; exponential modeling of time constants)?

2) What variables do you tend to analyze (e.g., SmO2 and/or THC)?

3) What modes of exercise (e.g., resistance exercise; cardiorespiratory exercise) do you most commonly use to assess the NIRS recovery response from?

4) When measuring the NIRS recovery response, do you have the participant remain still (i.e., passive assessment) or is the participant performing low-intensity exercise (i.e., active assessment)?

Thank you very much! 
Previous Topic | Next Topic

Quick Navigation:

Easily create a Forum Website with Website Toolbox.

HTML hit counter -