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Sustained aerobic exercise increases adult neurogenesis in brain -- ScienceDaily

The results indicate that the highest number of new hippocampal neurons was observed in rats that ran long distances and that also had a genetic predisposition to benefit from aerobic exercise: Compared to sedentary animals, HRT rats that ran voluntarily on a running wheel had 2-3 times more new hippocampal neurons at the end of the experiment. Resistance training had no such effect. Also the effects of HIT were minor. To conclude, only sustained aerobic exercise improved hippocampal neurogenesis in adult animals.