Brain
At rest, the human brain receives 15% of total cardiac output, and uses 20% of the body's energy consumption. The brain is normally dependent for its high energy expenditure upon aerobic metabolism. The brain as a result is highly sensitive to failure of its oxygen supply with loss of consciousness occurring within six to seven seconds, with its EEG going flat in 23 seconds. If it affected the oxygen and glucose supply to the brain, the metabolic demands of exercise could therefore quickly disrupt its functioning.
Protecting the brain from even minor disruption is important since exercise depends upon motor control, and particularly, because humans are bipeds, the motor control needed for keeping balance. Indeed, for this reason, brain energy consumption is increased during intense physical exercise due to the demands in the motor cognition needed to control the body.
Read more about this topic: Exercise Physiology
Famous quotes containing the word brain:
“Always in England if you had the type of brain that was capable of understanding T.S. Eliot’s poetry or Kant’s logic, you could be sure of finding large numbers of people who would hate you violently.”
—D.J. Taylor (b. 1960)
“She turns and looks a moment in the glass,
Hardly aware of her departed lover;
Her brain allows one half-formed thought to pass:
“Well now that’s done: and I’m glad it’s over.””
—T.S. (Thomas Stearns)
“who chained themselves to subways for the endless ride from Battery
to holy Bronx on benzedrine until the noise of wheels and children
brought them down shuddering mouth-wracked and battered bleak of brain and drained of brilliance in the drear light of Zoo,”
—Allen Ginsberg (b. 1926)