If you want a healthy brain – and keep it healthy as you age – there is one workout you need to do. A new study found that HIIT (High Intensity Interval Training) workouts can increase brain function. Researchers at University of Queensland in Australia found that doing HIIT workouts actually activate stem cells in our brain – and it only take six months of interval training to turn those cells on. And those workouts reap brain benefits for years – even after you stop doing them. According to researchers, the HIIT exercises actually changed the physical structure of the study participants’ brains, creating new connections that helped boost their thinking and memory skills.