Editing VO2 max (section)

{{Distinguish|Vanadium(IV) oxide}}
{{See also|Cardiorespiratory fitness}}
{{Short description|Maximum rate of oxygen consumption as measured during incremental exercise}}
{{Use dmy dates|date=January 2023}}
{{DISPLAYTITLE:VO<sub>2</sub> max}}
'''V̇O<sub>2</sub> max''' (also '''maximal oxygen consumption''', '''maximal oxygen uptake''' or '''maximal aerobic capacity''') is the maximum rate of [[respiration (physiology)|oxygen consumption]] attainable during physical exertion.<ref name=Clemente_et_al_2009>{{cite journal |author1=Clemente C. J. |author2=Withers P. C. |author3=Thompson G. G. | year = 2009 | title = Metabolic rate and endurance capacity in Australian varanid lizards (Squamata; Varanidae; Varanus) | journal = Biological Journal of the Linnean Society | volume = 97 | issue = 3| pages = 664–676 | doi=10.1111/j.1095-8312.2009.01207.x| doi-access = free }}</ref><ref name=Dlugosz_et_al_2013>{{cite journal | year = 2013 | title = Phylogenetic analysis of mammalian maximal oxygen consumption during exercise | url = http://jeb.biologists.org/content/jexbio/216/24/4712.full.pdf| journal = Journal of Experimental Biology | volume = 216 | issue = 24| pages = 4712–4721 | doi=10.1242/jeb.088914 | pmid=24031059| s2cid = 15686903 | doi-access = free | last1 = Dlugosz | first1 = Elizabeth M. | last2 = Chappell | first2 = Mark A. | last3 = Meek | first3 = Thomas H. | last4 = Szafrańska | first4 = Paulina | last5 = Zub | first5 = Karol | last6 = Konarzewski | first6 = Marek | last7 = Jones | first7 = James H. | last8 = Bicudo | first8 = Eduardo | last9 = Nespolo | first9 = Roberto F. | last10 = Careau | first10 = Vincent | last11 = Garland | first11 = Theodore }}</ref> The name is derived from three abbreviations: "V̇" for [[volume]] (the dot over the V indicates "per unit of time" in [[Newton's notation]]), "O<sub>2</sub>" for [[oxygen]], and "max" for maximum and usually normalized per kilogram of body mass. A similar measure is '''V̇O<sub>2</sub> peak''' ('''peak oxygen consumption'''), which is the measurable value from a session of physical exercise, be it incremental or otherwise. It could match or underestimate the actual V̇O<sub>2</sub> max. Confusion between the values in older and popular fitness literature is common.<ref name="pmid23935584">{{cite journal |last1=Smirmaul |first1=BP |last2=Bertucci |first2=DR |last3=Teixeira |first3=IP |title=Is the VO2max that we measure really maximal? |journal=Frontiers in Physiology |year=2013 |volume=4 |pages=203 |doi=10.3389/fphys.2013.00203 |pmid=23935584 |pmc=3733001|doi-access=free }}</ref> The capacity of the lung to exchange oxygen and carbon dioxide is constrained by the rate of [[blood#Oxygen transport| blood oxygen transport]] to active tissue. 

The measurement of V̇O<sub>2</sub> max in the laboratory provides a quantitative value of endurance fitness for comparison of individual training effects and between people in [[endurance training]]. Maximal oxygen consumption reflects [[cardiorespiratory fitness]] and [[endurance]] capacity in exercise performance. Elite athletes, such as [[long-distance running|competitive distance runners]], [[Road bicycle racing|racing cyclists]] or [[cross-country skiing (sport)|Olympic cross-country skiers]], can achieve V̇O<sub>2</sub> max values exceeding 90&nbsp;mL/(kg·min), while some endurance animals, such as [[Alaskan husky|Alaskan huskies]], have V̇O<sub>2</sub> max values exceeding 200&nbsp;mL/(kg·min).

In [[physical training]], especially in its academic literature, V̇O<sub>2</sub> max is often used as a reference level to quantify exertion levels, such as 65% V̇O<sub>2</sub> max as a threshold for sustainable exercise, which is generally regarded as more rigorous than [[heart rate#Maximum heart rate|heart rate]], but is more elaborate to measure.