Despite an ongoing discussion in the question of respiration as a possible limitation of performance, reality shows and with it the use of MOXY /NIRS, that respiration has a direct influence of O2 bio availability.
For all current MOXY user.
Mount one MOXY on a leg and one on an arm.
Make biceps curls and see SmO2 reaction in the arm, Make quadriceps activity and see SmO2 reaction in the leg. Both local feedback's.
Now create a hypocapnic situation and look at SmO2 trend and tHb trend and you have a systematic reaction in SmO2 as a shift in O2 Diss curve.
. Now create a hypercapnic situation and look the systemic reaction.
Now start thinking how hypo ventilation at the end of a 400 m run creates the pictures we see. Now go back to work done in the late 1970 with pH and so on and you understand that as long we can balance H + we can increase lactate in the system as one is a buffer the other is a limiter of ATP splitting.
Here a nice paper as well in that direction.
Related trends in locomotor and respiratory muscle oxygenation during exercise.
Legrand R1, Marles A, Prieur F, Lazzari S, Blondel N, Mucci P.
· 1Laboratory of Human Movement Studies, Faculty of Sports Sciences and Physical Education, Lille University, Lille, France.
We investigated the potential effect of respiratory muscle work on leg muscle oxygenation without artificial intervention in non-endurance-trained young subjects and searched for the range of intensity when this effect could occur.
We simultaneously monitored accessory respiratory and leg muscle oxygenation patterns with near-infrared spectroscopy (NIRS) in 15 healthy young men performing maximal incremental exercise on a cycle ergometer. Pulmonary gas exchange was measured. The respiratory compensation point (RCP) was determined. Oxygenation (RMO2) and blood volume (RMBV) of the serratus anterior (accessory respiratory muscle) and of the vastus lateralis (LegO2 and LegBV) were monitored with NIRS. The breakdown point of accessory respiratory muscle oxygenation (BPRMO2) and the accelerated (BP1LegO2) and attenuated fall (BP2LegO2) in leg muscle oxygenation were detected.
BPRMO2 occurred at approximately 85% .VO2max and was related to RCP (r = 0.88, P < 0.001). BP2LegO2 appeared at approximately 83% .VO2max and was related to RCP (r = 0.57, P < 0.05) and with BPRMO2 (r = 0.64, P = 0.01). From BP2LegO2 to maximal exercise, LegBV was significantly reduced (P < 0.05).
In active subjects exercising at heavy exercise intensities, we observed that the appearance of the accelerated drop in accessory respiratory muscle oxygenation-associated with high ventilatory level-was related with the attenuated fall in leg muscle oxygenation detected with near-infrared spectroscopy. This suggests that the high oxygen requirement of respiratory muscle leads to limited oxygen use by locomotor muscles as demonstrated in endurance-trained subjects. The phenomenon observed was associated with reduced leg blood volume, supporting the occurrence of leg vasoconstriction. These events appeared not only at maximal exercise
If you breathe at the end of a Wingate or 800 m run or 3 - 4 min all out test a VE of 130 - 150 L you look like you are out of breath?
Did you ever asked the question , that when the same person is breathing 150 - 200 L with a Spiro Tiger they are not out of breath after 5 min spiro tiger. Why not. ?