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Want to boost your will power against junk food? Hit the gym

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If you've ever left the gym and wondered why you're heading to the smoothie bar rather than seeking out that Big Mac you craved earlier in the day, a Harvard researcher has found the answer.

Physical activity rewires the brain to make it easier to avoid temptation.

Neurology professor Miguel Alonso Alonso's study of data, cultivated from previous epidemiological studies, found what many of us probably already know: Successful weight loss frequently depends on inhibitory control. In other words, the ability to resist temptation of that extra-large bowl of ice cream or the candy bar you want to eat after a full meal.

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But his work also showed that regular physical exercise can actual cause changes in the way the brain works. Specifically, going to the gym a few times a week (or otherwise staying active) increases the size of the area of the brain responsible for inhibitory control – basically the part of your brain that forces you say no to a second helping of pie even though you really, really, really want one.

"Regular exercise improves output in tests that measure the state of the brain's executive functions and increases the amount of grey matter and pre-fontal connections," Dr. Alonso Alonso said in a release. "In time, exercise produces a potentiating effect of executive functions including the ability for inhibitory control, which can help us to resist the many temptations that we are faced with everyday in a society where food, especially hypercaloric food, is more and more omnipresent."

Translation: exercise more, eat less.

In Canada, nearly one-quarter of adults are obese, according to Statistics Canada.

Meanwhile, only 15 per cent of adults and seven per cent of young people get the recommended amount of exercise.

If you are trying to lose weight but are having a hard time controlling what you eat, you may want to heed Dr. Alonso Alonso's words: "Physical exercise seems to encourage a healthy diet."

Does this research make you want to exercise more? Or are you a believer that exercise actually increases your appetite?

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