Talk:Respiratory exchange ratio

Latest comment: 6 years ago by Ioooi in topic Higher than 1.00

Untitled edit

The terms "Respiratory Exchange Ratio" (RER) and "Respiratory Quotient" (RQ) are very similar - but they are different. In my experience many individuals believe these terms to be synonymous. The distinction is the way in which each is measured. Respiratory Exchange Ratio is measured using indirect calorimetry, that is the amount of oxygen consumed and the amount of carbon dioxide produced. The respiratory quotient can be measured across a capillary bed of a particular organ or even a collection of cells in vitro. Most of the time RER and RQ are the same value, however, during a metabolic or respiratory acidosis/alkalosis RER and RQ do not have to be the same value. Valbaugh (talk) 11:45, 2 July 2009 (UTC)Reply

Higher than 1.00 edit

Correct me if I'm wrong, but isn't the only way that the RER can be higher than one by the production of extra CO2 by the bicarbonate buffering system during intense exercise? Other than that, there couldn't possibly be more CO2 produced than O2 uptaken. — Preceding unsigned comment added by 24.68.64.67 (talk) 04:07, 24 October 2011 (UTC)Reply

Yes, the RER can be >1 when the body starts the Anaerobic glycolysis in addition to aerobic respiration. In glycolysis, you get only some CO2 with zero additional oxygen consumed. The RER would be infinitely large (V(CO2) divided by zero) if the body could use 100% anaerobic glycolysis & 0% aerobic respiration, but in the real world there isn't enough glucose to use only anaerobic glycolysis (it spends about 16x more glucose per ATP than aerobic respiration due to its inefficiency), and the body never even tries to use only it. The body ends up using mostly aerobic respiration + SOME anaerobic respiration, and due to this the RER is usually never really much >1, usually RER=1,15 is the "endpoint" for all VO2max-measurements-tests in the endurance sport sciences. — Preceding unsigned comment added by Ioooi (talkcontribs) 12:25, 23 November 2017 (UTC)Reply

RER calculation edit

VO2 STPD/VCO2 STPD = RER VALUE, for example 1.14(L/min)/1.03(L/min)= 0.90 RER