ump in the pool!

I am a neurobiologist trained in brain physiology, fitness enthusiast and mother and I spend many hours at the local swimming pool during the summer. 

It's not uncommon to see children splashing and swimming merrily while their parents sunbathe in the distance - and I myself have been one of the parents who observed the swimming pool from the sidelines plenty of times with lifeguard recertification near me.

However, if more adults knew about the cognitive and mental health benefits of swimming, they might be more likely to jump in the pool with their children.



New, improved brain cells and compounds

Until the 1960s, researchers believed that the number of neurons (nerve cells in the brain, ed.) And so-called synaptic connections in the human brain were limited and that these brain cells were irreplaceable once they were damaged. 

But that idea was disproved when researchers began to see ample evidence for the formation of neurons - so-called neurogenesis  - in adult brains of humans and other animals .

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There is now clear evidence that aerobic exercise can contribute to neurogenesis and play a central role in helping to reverse or repair damage to neurons and their connections in both mammals and fish.

Research shows that the changes in response to exercise occur mainly through increased levels of a protein called ' brain-derived neurotrophic factor ' (BDNF).

Reduces anxiety and depression

The neuroplasticity (the professional term for the brain's ability to change) that the protein stimulates has been shown to increase cognitive function , including learning and memory with American lifeguard association.

Studies in humans have found a strong link between the concentration of BDNF circulating in the brain and an increase in the size of the hippocampus (the area of ​​the brain responsible for learning and memory). 

An increased level of BDNF has also been shown to sharpen cognitive performance as well as help reduce anxiety and depression.

Researchers have also observed mood disorders in patients with a lower concentration of BDNF.

Aerobic exercise also promotes the release of specific chemical messengers called neurotransmitters (chemical substances that are released in synapses and transmit the signal from one neuron to another neuron, ed.)

Improved memory, mood and cognition

One of these neurotransmitters is serotonin, which - when present at elevated levels - reduces depression and anxiety as well as lifts the mood .

In studies with fish, researchers have observed changes in the genes responsible for increasing the concentration of BDNF as well as improved development of the so-called dendritic 'spines' - protrusions on the dendrites, which are the part of the nerve cell that receives impulses from other nerve cells - after eight weeks of training in relation to control groups.

This is consistent with studies in mammals where may increase neuronal spine density. These changes have been shown to contribute to improved memory, mood as well as improved cognition in mammals. 

The greater spine density helps neurons build new connections and send more signals to other nerve cells. Repeating the signals may strengthen the connections.

Why is swimming something special?

Scientists do not yet know what it is that makes swimming something very special, but they are approaching the answer.

We have long known about the cardiovascular benefits of swimming. Because swimming involves all the major muscle groups, the heart has to work hard , which increases blood flow throughout the body. This leads to the formation of new blood vessels, a process called angiogenesis. 

The greater blood flow can also lead to a large release of endorphins - hormones that act as natural pain relief throughout the body.


Reduces the cognitive effects due to aging

Most of the research working on understanding how swimming affects the brain has been done with rats, which is a good laboratory model because of their genetic and anatomical resemblance to humans.

A study in rats showed that swimming stimulates brain pathways that suppress inflammation in the hippocampus and inhibit apoptosis - a process by which cells destroy themselves.

The study also showed that swimming can help support neuronal survival as well as reduce the cognitive effects of aging.