Running may boost beneficial brain changes

As the days grow longer and the weather gets warmer, you may notice more people out on the roads enjoying a jog. If you've ever pounded the pavement, you may have experienced "Runners high" - an almost euphoric state, which precedes a period of pacing. Now, researchers at NYU have given us a better idea of what is behind this and the other beneficial impacts of exercise. Julia Ravey covered this story and thought it would be interesting to explain it whilst running. So let's see how she fared...

Julia - I'm out on a jog today and I'm going to be honest, I'm not the biggest fan of running when I'm doing it. But afterwards, I always feel amazing. And this is potentially from alterations to chemicals in my brain. Margaret Rice, from NYU, studies this process, and those benefits go beyond just feeling good...

Margaret - Among the beneficial effects are improved motor activity, this is known in Parkinson's patients who exercise. Exercise also improves symptoms of depression and of anxiety.

Julia - But the exact changes which occur are still under investigation. So Margaret and her team wanted to explore exercise's impact on the brain.

Margaret - We put mice on running wheels and compared them to mice that were housed with a running wheel, but that was locked. And then we allowed these two groups of mice access to the wheel for 30 days. We examined the brains for dopamine, which is an important neurotransmitter in motor and reward pathways. And we looked at brain derived neurotrophic factor (BDNF), which promotes growth of neurons, survival of neurons. And we found that there was no change in dopamine levels, but that brain derived neurotrophic factor did go up in motor regions of the striatum.

Julia - The striatum is a brain region buried deep in the brain, sort of on the level of the ears and eyes - where they'd crossover. It's important in moving and also in detecting reward. Running also has a longer term impact on activity in this region.

Margaret - The change in BDNF was not particularly prolonged, but what we found was that dopamine release in brain slices from these mice was enhanced. This wasn't just an enhancement in the motor region, but also in reward regions of the striatum and those effects persisted for at least seven days, for a week, after we stopped the mice from running.

Julia - And it looks like BDNF and dopamine interacted in these events.

Margaret - We did look at mice that have half the levels of BDNF and we found that in those mice, there was no elevation of BDNF with running, and there was no increase in dopamine release.

Julia - A disorder caused by the loss of dopamine is Parkinson's disease, when neuron's making this chemical die. And in mouse models mimicking this condition, BDNF has been implicated in protecting brain cells, meaning boosting its levels via exercise...

Margaret - ...could help protect the dopamine neurons as well as to boost release from the remaining dopamine neurons.

Julia - So exercise could provide benefits in early stage Parkinson's disease. And in terms of a "runners high", this long-lasting impact of dopamine signalling could contribute.

Margaret - It's already been shown that dopamine release goes up when rodents run anyway, because it's a motor pathway transmitter. And so part of our motor behavior requires dopamine.

Julia - That's brilliant. I went on a run today and I always feel much better after I finish. I just feel so much happier, my mood is boosted and I have a much clearer head.

Margaret - Right. And I find that to be enduring. And I think that could be some of the long-term effects that we see from dopamine as well as the other beneficial effects on other transmitter systems that I'm sure occur as well.

Julia - So it looks like exercise gives our brains a boost, both in terms of feeling good, via dopamine release and could even help protect our brain cells. So pick your favorite exercise could be running, dancing, walking, anything you want and get moving.