One 30-Minute Exercise Session Provides Instant Antidepressant Benefits

Just 30 minutes of moderate exercise can provide an immediate boost in mood, according to new research. Scientists have discovered that this effect, observed in mice and likely applicable to humans, is driven by the release of a hormone called adiponectin, which travels to the brain and activates regions responsible for emotional regulation. The uplift in mood may last for hours, though the exact duration in humans has not yet been determined.

The findings have significant implications. For those who can exercise, even one session could temporarily ease symptoms of anxiety or depression. Additionally, understanding this mechanism could inspire the development of fast-acting antidepressant medications, working more quickly than traditional treatments such as SSRIs.

Neurobiologist Sonata Suk-yu Yau from Hong Kong Polytechnic University told Psypost, "Rapid-acting antidepressant treatments with long-lasting effects and minimal side effects remain rare. This study provides clinical evidence that a single session of exercise can alleviate depressive symptoms."

While regular physical activity is known to prevent and treat mild to moderate depression, the effects of a single bout of exercise have been less studied. Emerging evidence indicates that even brief sessions can improve mood, and Yau's team aimed to quantify this impact and uncover the underlying mechanism.

The study involved 40 adult participants aged 18 to 40, along with several dozen mice in various experimental groups. Participants completed a Profile of Mood States survey, ran on a treadmill for 30 minutes while monitored for heart rate, and then retook the survey. Results showed a notable mood improvement across all participants. Those with anxiety or depression reported lower levels of anger, confusion, fatigue, and anxiety, while feelings of vigor and self-esteem increased in all subjects.

To understand the biological mechanism, researchers turned to mice. Some mice were exposed to a chronic unpredictable stress protocol to simulate depression-like symptoms, including reduced grooming, exploration, and mobility. Both stressed and unstressed mice then performed a moderate treadmill exercise, which led to elevated mood-related behaviors such as increased grooming and mobility. These effects were observed up to 24 hours post-exercise but declined by 48 hours.

Analysis revealed higher levels of adiponectin in both blood and the medial prefrontal cortex, which includes the anterior cingulate cortexa brain region critical for emotional regulation. Adiponectin activates a receptor called AdipoR1 in certain neurons. Blocking this receptor eliminated the mood-enhancing behaviors. Further study showed that AdipoR1 triggers a protein called APPL1, which enters the neurons nucleus and initiates molecular changes that strengthen synapses. The neurons also formed new dendritic spines, a process blocked when APPL1 was inhibited, suggesting a direct link to mood improvement.

The mechanism is similar to effects seen with ketamine, hinting at shared pathways for rapid mood enhancement. Targeting AdipoR1 may offer a promising route for new antidepressant treatments. Synthetic adiponectin receptor agonists like AdipoRon are being explored, though they have not yet been tested in humans.

Yau stated, "Our goal is to create population-based guidelines for single-session exercise prescriptions that improve mood and prevent the onset of depression."

The full research has been published in Molecular Psychiatry.

Author: Sophia Brooks