This makes sense, but is a weird thing to think about. Drug addiction may be more difficult to kick if it became habitual while exercise if part of your routine:
It does indicate that shedding an addiction acquired when a person has been exercising could be extra challenging, he says.
“But, really, what the study shows,” he continues, “is how profoundly exercise affects learning.”
When the brains of the mice were examined, he points out, the runners had about twice as many new brain cells as the animals that had remained sedentary, a finding confirmed by earlier studies. These cells were centered in each animal’s hippocampus, a portion of the brain critical for associative learning, or the ability to associate a new thought with its context.
So, the researchers propose, the animals that had been running before they were introduced to cocaine had a plentiful supply of new brain cells primed to learn. And what they learned was to crave the drug. Consequently, they had much more difficulty forgetting what they’d learned and moving on from their addiction.
That same mechanism appeared to benefit animals that had started running after becoming addicted. Their new brain cells helped them to rapidly learn to stop associating drug and place, once the cocaine was taken away, and start adjusting to sobriety.
“Fundamentally, the results are encouraging,” Dr. Rhodes says. They show that by doubling the production of robust, young neurons, “exercise improves associative learning.”
But the findings also underscore that these new cells are indiscriminate and don’t care what you learn. They will amplify the process, whether you’re memorizing Shakespeare or growing dependent on nicotine.