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Researchers say our brains are probably wired from an evolutionary sense to encourage running and high aerobic activities. Above, a man runs past the Sydney Harbour Bridge on April 22.
‘Wired To Run’: Runner’s High May Have Been Evolutionary Advantage
Author: CHRISTOPHER JOYCE
Endurance athletes sometimes say they're "addicted" to exercise. In fact, scientists have shown that rhythmic, continuous exercise — aerobic exercise — can in fact produce narcoticlike chemicals in the body.
Now researchers suggest that those chemicals may have helped turn humans, as well as other animals, into long-distance runners.
The man behind the research is University of Arizona anthropologist David Raichlen, a runner himself. He does about 25 miles a week.
Being human, Raichlin has some tools that help — short toes that don't get in the way, for example, and big joints in the legs to absorb shock. But he thinks humans are also "wired to run."
"Wired to run, meaning that our brains are probably, have been sort of rewired from an evolutionary sense to encourage these running and high aerobic-activity behaviors," Raichlen says.
Many anthropologists think early humans learned to run long distances to chase down and exhaust prey, like antelopes.
Meat is one payoff for runners. But Raichlen thinks there may have been another reward: a runner's high. He designed an experiment to test this idea.
Read more at NPR