Running and other exercise could help rebuild parts of the brain that are lost with age, according to a new study.
Scientists in Germany carried out new research in mice, which showed that dormant nerve cells in the hippocampus – the part of the brain that plays a key role in learning and memory – could be "kick-started" into action by exercise.
The study at the Max Planck Institute of Immunobiology also found that epileptic seizures may trigger brain cell regeneration.
It used to be thought that, from birth onwards, brain cells died off and were not replaced. But the study has revealed that at least some nerve cells can be replenished.
The scientists found that physically active mice developed more newborn hippocampal neurons than inactive animals.
It is hoped the discovery will help the scientists to find new ways to treat age-related memory loss, the effects of brain injuries or Alzheimer's disease.
"Running promotes the formation of new neurons," said study leader Dr Verdon Taylor, from the institute based in Freiburg.