Editing Exercise physiology (section)

=== Cerebral oxygen ===
[[Autoregulation#Cerebral autoregulation|Cerebral autoregulation]] usually ensures the brain has priority to cardiac output, though this is impaired slightly by exhaustive exercise.<ref>{{Cite journal |last=Ogoh |first=S |last2=Dalsgaard |first2=MK |last3=Yoshiga |first3=CC |last4=Dawson |first4=EA |last5=Keller |first5=DM |last6=Raven |first6=PB |last7=Secher |first7=NH |year=2005 |title=Dynamic cerebral autoregulation during exhaustive exercise in humans |journal=American Journal of Physiology. Heart and Circulatory Physiology |volume=288 |issue=3 |pages=H1461–7 |doi=10.1152/ajpheart.00948.2004 |pmid=15498819}}</ref> During submaximal exercise, cardiac output increases and cerebral blood flow increases beyond the brain's oxygen needs.<ref>{{Cite journal |last=Ide |first=K |last2=Horn |first2=A |last3=Secher |first3=NH |year=1999 |title=Cerebral metabolic response to submaximal exercise |journal=Journal of Applied Physiology |volume=87 |issue=5 |pages=1604–8 |citeseerx=10.1.1.327.7515 |doi=10.1152/jappl.1999.87.5.1604 |pmid=10562597}}</ref>  However, this is not the case for continuous maximal exertion: "Maximal exercise is, despite the increase in capillary oxygenation [in the brain], associated with a reduced mitochondrial O<sub>2</sub> content during whole body exercise"<ref>{{Cite journal |last=Secher |first=NH |last2=Seifert |first2=T |last3=Van Lieshout |first3=JJ |year=2008 |title=Cerebral blood flow and metabolism during exercise: Implications for fatigue |journal=Journal of Applied Physiology |volume=104 |issue=1 |pages=306–14 |doi=10.1152/japplphysiol.00853.2007 |pmid=17962575}} page 309</ref>  The autoregulation of the brain's blood supply is impaired particularly in warm environments<ref>{{Cite journal |last=Watson |first=P |last2=Shirreffs |first2=SM |last3=Maughan |first3=RJ |year=2005 |title=Blood-brain barrier integrity may be threatened by exercise in a warm environment |journal=American Journal of Physiology. Regulatory, Integrative and Comparative Physiology |volume=288 |issue=6 |pages=R1689–94 |doi=10.1152/ajpregu.00676.2004 |pmid=15650123}}</ref>