Exercise for the brain
Hunting, gathering food, exploring the environment - our ancestors were constantly on the move. Does this explain why exercise also keeps you mentally fit?
In the 1990s, neuroscientists made a series of discoveries that shattered a fundamental assumption in their discipline: for decades it had been assumed that the mature brain of adult mammals was no longer able to form new neurons. The nerve cells that die off during aging could therefore not be replaced under any circumstances. But there was growing evidence that new neurons can also develop in older individuals. Researchers published one of the most exciting experiments in 1999 in the journal "Nature Neuroscience". At the Salk Institute for Biological Studies in California, they observed a particularly large number of newly formed nerve cells in the hippocampus of mice that were allowed to run on a wheel – a brain structure that is responsible for important memory functions.
Investigations in the years that followed suggested that physical activity also had a positive effect on the human brain. According to various studies, exercise could even reduce the risk of Alzheimer's dementia and other neurodegenerative diseases. But why does sport have any influence here at all? We can easily understand that it strengthens body organs such as the heart and lungs. When we jog, for example, our muscles need more oxygen, and over time the cardiovascular system responds to the increased demands by making the heart larger and forming new blood vessels. This response is useful to increase physiological performance. But why the brain also adapts is not so obvious. After all, you don't have to think too much when running or hiking, do you? Perhaps we can understand the connection better if we consider the way our ancestors lived…
