Even if you really don't want to exercise, engaging in physical activity can still have benefits for your mental health, a new animal study suggests.
Researchers found that depression and anxiety symptoms in rats are reduced with exercise -- even if it's forced, not voluntary, exercise.
"The implications are that humans who perceive exercise as being forced -- perhaps including those who feel like they have to exercise for health reasons -- are maybe still going to get the benefits in terms of reducing anxiety and depression," study researcher Benjamin Greenwood, who is an assistant research professor in integrative physiology at the University of Colorado, Boulder, said in a statement.
The study, published in the European Journal of Neuroscience, involved having rats either exercise on a wheel or be sedentary for six weeks. Among the rats that exercised, half of them were forced to do so by putting them on a motorized wheel at predetermined times, while the other half were allowed to exercise as they pleased.
After the six-week period, researchers tested the rats' stress and anxiety levels. They found that the rats that exercised -- whether voluntarily, or forced to by the researchers -- experienced less stress and anxiety than the mice that were sedentary.
For humans, the Mayo Clinic reports that some of exercises's positive effects on mental health may come from the body's release of feel-good hormones. For more mental health benefits of exercise, click through the slideshow:
It Sharpens Thinking
Earlier this year, Dartmouth researchers <a href="http://www.huffingtonpost.com/2012/05/31/exercise-makes-you-smarter-adhd-research_n_1528383.html">added support to mounting evidence about the way that exercise affects learning</a> and mental acuity: it boosts the production of “brain derived neurotrophic factor" -- or BDNF – a protein that is thought to help with mental acuity, learning and memory.
It May Alleviate Childhood ADHD Symptoms
In the same Dartmouth study, the researchers discovered that, thanks to the BDNF boost, exercise also helped to <a href="http://www.wired.com/playbook/2012/05/exercise-memory-and-adhd/">alleviate ADHD-like symptoms in juvenile rats</a>. Since BDNF is involved in the brain's development and growth of new cells, the effect was more profound on the younger rats, with their still-developing brains and more rapid cell turnover, compared to adult rats.
It Helps You Learn New Tricks
Even one exercise session can help you retain physical skills by enhancing what's commonly known as "muscle memory" or "motor memory," according to <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3433433/">new research published in <em>PlosOne</em>.</a> <a href="http://well.blogs.nytimes.com/2012/09/26/how-exercise-can-help-you-master-new-skills/">As the New York <em>Times</em> reported</a>, men who were taught to follow a complicated pattern on a computer and subsequently exercised were better able to remember the pattern in subsequent days than the men who didn't exercise after the initial squiggle test.
It Supports Problem-Solving
In one study, mice that exercised by running not only generated new neurons, but those neurons lit up when the mice performed unfamiliar tasks like <a href="http://www.nytimes.com/2012/04/22/magazine/how-exercise-could-lead-to-a-better-brain.html?pagewanted=all">navigating a new environment</a>.
It Helps Alleviate Symptoms Of Depression
When you exercise, your pituitary gland releases endorphins to help mitigate the physical stress and pain you are experiencing. But those endorphins may play a more important and longer-lasting role: they could help alleviate symptoms of depression, <a href="http://www.mayoclinic.com/health/depression-and-exercise/MH00043">according to a Mayo Clinic report</a>.
It Reduces Stress
Although exercising raises our levels of cortisol -- the hormone that causes physical stress and is even associated with long-term memory impairment -- its overall effect is one of a stress reducer. That's because exercise increases the <a href="http://www.hormones.gr/57/article/article.html">body's threshold for cortisol</a>, making you more inured to stressors.
It Helps Delay Age-Associated Memory Loss
As we get older, an area of the brain called the hippocampus shrinks. That's why age is associated with memory loss across the board. However, profound memory loss -- such as in dementia and Alzheimer's disease patients -- is also contributed to by accelerated hippocampus shrinking. Luckily, the hippocampus is also an area of the brain that generate new neurons throughout a lifespan. And, <a href="http://www.npr.org/2011/02/21/133777018/aerobic-exercise-may-improve-memory-in-seniors">the research shows</a>, exercise promotes new neural growth in this area.