In times of serious stress, people might turn to exercise to blow off steam and shake off nervous energy. However, despite anecdotal evidence, the link between working out and relieving stress isn’t well understood by scientists. Researchers haven’t yet pinned down exactly how exercise modulates stress in the brain and body, despite knowing that exercise benefits mental health.
In a recent study conducted in mice, researchers became one step closer to that understanding, discovering that exercise actually strengthens the brain’s resilience to stress. Exercise helps animals cope with stress by enabling an uptick in a crucial neural protein called galanin, the study suggests. This process influences stress levels, food consumption, cognition, and mood.
Leveraging this finding, researchers were able to genetically tweak even sedentary mice’s levels of galanin, shifts that lowered their anxious response to stress.
The study’s authors explain that this study helps pin down the biological mechanisms driving exercise’s positive effects on stress. While further human experiments are needed to confirm these findings, the researchers have practical advice for people looking to get these benefits: perform regular, aerobic exercise.
“Not exercising at all and then suddenly going for a hard 10 mile run just before a stressful event isn’t as helpful as regularly jogging 3 miles several days a week over several months,” researchers David Weinshenker and Rachel Tillage, tell Inverse by email.
That’s because, based on these results, a history of increased exercise doesn’t affect the immediate physiological response (like a release of cortisol) during a stressful event, Weinshenker and Tillage explain. Instead, exercise increases behavioral resilience after stress exposure.
“This could suggest that increased exercise doesn’t impact our immediate feelings of stress, but does allow us to cope with stress in a healthier way,” the co-authors say.
These findings were released Monday in the Journal of Neuroscience.
The search for the brain mechanisms — Research shows exercise protects against the deleterious effects of stress in both mice and humans. Galanin, that pivotal brain protein that modulates stress and mood, is expressed in similar areas of both animal’s brains.
To examine how these factors interact and influence each other, the study team turned to mice.
“Mechanistic questions are difficult to answer in humans due to ethical and technical limitations, so we used mice for this purpose,” Weinshenker and Tillage say. With these overlapping properties, the team adds that the neurobiological substrates underlying galanin’s role in physical activity-related stress resilience could occur across species.
“One of the major implications from this study in that the galanin system could be a potential target for future therapies… “
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