One of our interesting task over all this years is to find an option to close the gap between science in the lap and the grass root user outside in the field.
We are absolutely aware that there will be many compromises to be made to move the great development of information's we now can gather in labs into the field.
There is no discussion anymore, that using live data are the way to go as they are LIVE and individual and that scientific statistic are great but have the limitation of any statistic.
220 - age . % VO2 max. lactate threshold ideas and so on.
No wonder there is a rush out there to develop bio markers we can see live like HR as the oldest one, now more an more respiratory feed backs since the start by Zephyr with the bioharness and the latest kid in the block is NIRS as it is now cheap available and you can use a watch like a garmin watch with SmO2 and tHb live numbers nd graph..
So we are getting closer to end speculations and usemathematical formulas and can replace them with live feedback.
A super interesting situation is the section we see developing in cycling, where they use the W bal we discussed on other areas here.
Great concept great ideas great theory and great calculations.
BUT not live as real feedback from the muscles.
So to close the gap between this ideas and NIRS we need some papers who show how they connect with each other.
So here the picture of closing the gap followed by some intriguing studies to show that NIRS/MOXY may just be the real deal for live feedback instead of calculations and hope.
paper on recovery W. bal and real substrate like Pcr.
Intramuscular determinants of the ability to recover work capacity above critical power
PurposeThe primary purpose of this investigation was to compare the recovery of the W′ to the recovery of intramuscular substrates and metabolites using 31P- and 1H-magnetic resonance spectroscopy.
MethodsTen healthy recreationally trained subjects were tested to determine critical power (CP) and W′ for single-leg-extensor exercise. They subsequently exercised in the bore of a 1.5-T MRI scanner at a supra-CP work rate. Following exhaustion, the subjects rested in place for 1, 2, 5 or 7 min, and then repeated the effort. The temporal course of W′ recovery was estimated, which was then compared to the recovery of creatine phosphate [PCr], pH, carnosine content, and to the output of a novel derivation of the W′BAL model.
ResultsW′ recovery closely correlated with the predictions of the novel model (r = 0.97, p = 0.03). [PCr] recovered faster (t12 =38s)than W′(t12 =232s)The W′ available for the second exercise bout was directly correlated with the difference between [PCr] at the beginning of the work bout and [PCr] at exhaustion (r = 0.99, p = 0.005). Nonlinear regression revealed an inverse curvilinear relationship between carnosine concentration and the W′t1/2 (r2 = 0.55).
ConclusionThe kinetics of W′ recovery in single-leg-extensor exercise is comparable to that observed in whole-body exercise, suggesting a conserved mechanism. The extent to which the recovery of the W′ can be directly attributed to the recovery of [PCr] is unclear. The relationship of the W′ to muscle carnosine content suggests novel future avenues of investigation.
Now look here the interesting trend between SmO2 and PCr and combine the W' with PCr and SmO2.
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 , Kevin K. McCully
Journal of Applied Physiology Published 15 December 2013 Vol. 115 no. 12, 1757-1766 DOI: 10.1152/japplphysiol.00835.2013
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.
What are the possible thoughts you can make ?