A similar dynamic may have motivated early humans to whistle or hum while they hunted or tilled and later to raise their voices in song during barn raisings and other intense physical labor, he said.
But why orchestrating your own soundtrack should have more physical benefit than merely hearing similar music in the background is not altogether clear.
“We think that the observed effects are most probably due to a greater degree of emotional motor control,” when you actively engage in making music, Dr. Fritz said. Emotional motor control, as opposed to the more workaday “deliberate” type that normally guides our muscular movements, he said, operates almost below consciousness. Your body responds to it with little volition and you move, he said, with reduced effort and increased joy. This is “musical ecstasy,” Dr. Fritz said, and it seems to have permeated, to some degree, the gym where the exercisers composed music while sweating.
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