The Benefits of Swimming for Mental Health: The Relationship Between Aquatic Exercise and Anxiety, Depression

Introduction

According to a survey by Taiwan’s Ministry of Health and Welfare, approximately 8.9% of Taiwanese adults experience depressive symptoms, with an even higher prevalence of anxiety disorders. Following the COVID-19 pandemic, the rate of people seeking help for mental health issues has risen significantly, yet due to insufficient psychiatric resources and the stigma surrounding seeking treatment, many individuals still do not receive adequate assistance.

Beyond medication and psychological counseling, regular exercise has been recognized by mainstream psychiatric science as an effective adjunctive intervention for alleviating mild to moderate anxiety and depression. Swimming, in particular, stands out among all forms of exercise for its mental health benefits, owing to its unique sensory environment and full-body physiological effects.

The Neurobiological Mechanisms Behind Swimming’s Mental Health Benefits

Release of Endorphins and Serotonin

Aerobic exercise stimulates the brain to secrete various neurotransmitters that positively influence mood:

• Endorphins: Secreted in large quantities during swimming, these are natural “feel-good hormones” that temporarily block pain signals and produce a sense of euphoria (commonly known as the “swimmer’s high”)
• Serotonin: Regular aerobic exercise raises brain serotonin levels, which is precisely the primary mechanism of action of most antidepressant medications
• Dopamine: Associated with motivation and reward, the post-exercise boost in dopamine can improve low mood states
• Norepinephrine: Enhances alertness and energy levels, countering the fatigue and lethargy commonly seen in depression

Brain-Derived Neurotrophic Factor (BDNF)

BDNF is known as “fertilizer for the brain,” promoting neuronal growth and connectivity while enhancing brain plasticity. Individuals with anxiety disorders and depression generally have lower BDNF levels, and aerobic exercise—especially moderate-intensity exercise sustained for more than 20 minutes—is one of the most effective natural promoters of BDNF.

The Sensory Healing Effects of Water

The psychological benefits of swimming stem not only from the exercise itself but also from water as a unique sensory environment:

• Blue Space Effect: Research shows that environments near water can lower cortisol levels and enhance subjective well-being. The color of the pool water, the sound of water, and the tactile sensation of water can all activate this effect.
• Rhythmic breathing patterns: Swimming mandates a regular breathing rhythm (e.g., breathing every three strokes in freestyle), similar to meditative breath control, which activates the parasympathetic nervous system and reduces anxiety responses.
• Sensory simplification: The underwater world blocks visual and auditory stimuli (phone notifications, office noise), functioning like a meditative “digital detox” that allows an overactive mind to rest.
• The enveloping sensation of water pressure: The uniform pressure water exerts on the entire body resembles the calming effect of deep pressure touch therapy (commonly used for autism and anxiety disorders).

Research-Supported Mental Health Benefits

Comparison with Land-Based Exercise Such as Running

Swimming’s mental health benefits are comparable to those of other aerobic exercises, but it holds advantages in the following areas:

• For those with social anxiety or body image concerns: The underwater environment of a pool offers relative privacy, without the need to face others’ gazes; swimwear culture is also gradually becoming more diverse and inclusive
• For depressed patients with chronic pain: Swimming allows for sufficient exercise volume without exacerbating pain
• Long-term adherence rates: Research shows that long-term exercise adherence is higher for swimming than for running, likely because swimming is gentler on the joints and provides a pronounced immediate sense of pleasure

Practical Applications of Swimming as a Mental Health Tool

Specific Approaches for Individuals with Anxiety Disorders

Individuals with anxiety disorders may face challenges when first attempting to swim, particularly fear of water or social anxiety about the public pool environment. Here are progressive recommendations:

1. Start with walking in the shallow end; there is no need to push yourself to complete a lap
2. Practice slow, deep breathing in the water (inhale for 4 seconds, exhale for 6 seconds), feeling the water’s resistance against your chest
3. Try back floating: let your body fully relax on the water’s surface and feel the sense of security of being supported by the water—this in itself is an excellent relaxation exercise
4. Set small goals (e.g., “swim 4 laps today”), give yourself positive affirmation upon completion, and build self-efficacy

Considerations for Individuals with Depression

One of the core symptoms of depression is anhedonia, which makes it extremely difficult for patients to take the first step toward “going swimming.” The following strategies may help:

• Lower the threshold: Tell yourself “just go to the pool; it’s fine if you don’t swim,” reducing the psychological pressure of entering the pool
• Buddy system: Arrange to swim with family or friends, using social commitment to boost motivation
• Fixed schedule: Put swimming into your calendar and treat it as part of your treatment, just like seeing a doctor
• Mood tracking: Keep a brief journal rating your mood before and after swimming (on a scale of 1-10) to observe consistent positive correlations

Practical Tips

1. Don’t aim for performance: Swimming for mental health purposes does not require timing or counting laps. Let swimming become a meditative time to enjoy the present moment, rather than another task that needs to be accomplished.

2. Feel the presence of water: While swimming, deliberately focus your attention on the sensation of water against your skin, the feeling of water flowing through your fingers, and the quiet sounds underwater—this is a natural form of “Mindful Swimming.”

3. Choose the right time of day: If you experience morning depression (worst mood in the morning), afternoon swimming generally works better; if work stress is your primary stressor, evening swimming can help you transition from “work mode” to “life mode.”

4. Make swimming a social activity: Join a community swimming class and build relaxed social connections with regular classmates. This is especially beneficial for those with anxiety or depression who struggle with feelings of isolation.

5. Don’t rely on exercise alone for severe depression: Swimming is a supplementary tool. For those with severe depressive disorder, psychiatric medication and psychotherapy should still be pursued. If you have thoughts of self-harm, seek help immediately (Taiwan Suicide Prevention Hotline: 1925).

Conclusion

In Taiwan’s mental health care system, non-pharmacological self-help interventions have long been underappreciated. Swimming offers a scientifically supported, practically feasible, and multi-faceted self-care tool—from the neurobiological mechanisms of endorphins, to the sensory healing of blue spaces, to the sense of belonging fostered through social interaction.

If you or someone around you is facing emotional distress, consider adding swimming to your self-care “toolkit.” You don’t need to become an elite swimmer—you only need to be willing to step into the water and let its embrace carry away some of life’s burdens.

Related Reading

• The Benefits of Swimming for Mental Health: Relieving Anxiety and Depression
• How Swimming Improves Depression: The Neural Mechanisms of Aerobic Exercise Promoting Serotonin Secretion
• Swimming and Mental Health: Scientific Research on Underwater Meditation and Stress Reduction
• Swimming and Stress Management: Practical Methods of Underwater Meditation and Research on the Mental Health Benefits of Regular Swimming