
Why Does Cold Water Swimming Boost Immunity?
Swimming is a form of exercise that has many benefits. When you swim, you’re not only using many muscle groups, but also improving cardiovascular health. You can also combat obesity and other related diseases by swimming regularly because of the added calorie burn that comes from the resistance of working out in water.
It’s hard to find any drawbacks to adding swimming to your physical health routine. However, when many think of jumping into a body of water or pool at home, they picture a sunny day, hot weather, and the refreshing feeling of water that’s just cool enough. But what about cold water swimming? Hear us out!
Cold water swimming immerses you in ice or near ice-cold water for health benefits. It’s sometimes referred to as winter swimming or ice swimming. Ice swimming is a more intense version and involves people breaking ice on a body of water and swimming in the water below.
This form of swimming might sound a little daunting at first. But what are the benefits of cold water swimming? And why is it so good for your immune system in particular? Let’s find out.
Is plunging into cold water good for you?
People from the northern part of the world have been swimming in cold water for ages. The act is considered a tradition in many parts of the world where cold weather is often the standard. In recent years, many athletes and health enthusiasts have adopted cold water swimming as a part of their overall workout routine to improve their health.

Image by Mika on Unsplash: What are the long-term effects of cold water swimming?
What are the benefits of cold water swimming?
Cold water swimming puts heavy physiological stress on the body. That may seem like a bad thing, but in fact, that shock to the system can provide some great health benefits.
Various aspects of health can be positively affected by cold water swimming, such as:
- Hematological (blood health)
- Endocrine (hormones and messaging in the body)
- Upper respiratory tract health
- Mental and mood health
- General wellbeing
When looking at the organs and organ systems affected by cold water swimming, there are a few specific benefits to pay attention to. In terms of the endocrine system and cold water swimming, research shows that immersing oneself in cold water temperatures can help to:
- Reduce triglycerides
- Increase the body’s ability to use insulin, a hormone responsible for regulating blood sugar levels
- Decrease a hormone known as norepinephrine, which is associated with an increased risk of heart attack if levels are high
- Reduce blood pressure
- Improve physiological response to stress
- Reduce pain perception in the body
Swimming in zero-temperature water has also been shown to improve mental health; studies have found that the activity possesses antidepressant effects. It is thought that hormones tied to mood regulation are positively affected by cold swimming in a way that can help a person with depression or anxiety feel better in the long run.
One specific case study examined a woman on conventional antidepressant medication who decided to add cold water swimming to her routine. After a year of consistently engaging in the activity, she was medication-free, and symptoms were dramatically reduced. The specific hormones involved in the changes were norepinephrine and B-endorphins.
How does cold water swimming boost the immune system?
One of the most notable effects of cold water swimming on physiological health is a boost in immunity. There are many reasons why participating in this activity helps to improve the regulation and function of our body’s first line of defence.
For instance: cold water swimming affects the blood and the immune aspects found in the blood. In the short term, immunity is boosted almost immediately because the shock to the system primes itself to fight off infection. When someone immerses themselves in cold water, stress levels elevate and relay a message to the immune system that they should prepare for battle.

Image by Sanni Sahil on Unsplash: How long should you do cold water swimming?
When it comes to blood cells that take action for the immune system, cold water swimming has been shown to increase levels of leucocytes and monocytes. Both are types of white blood cells designed to hunt and kill viruses, bacteria, and other foreign pathogens. When the army of these cells is more prominent, it is easier for your body to fight off infection. This cell increase after cold water swimming is also likely due to stress in the body that causes the immune system to act.
Some other evidence that points to better immune health revolves around cold swimmers and the frequency of lung infections. People who participated in regular swim sessions in ice water were found to have fewer infections. If they did get sick, the illness didn’t last as long and the symptoms were milder.
What are the risks of cold water swimming?
Cold water swimming does provide health benefits, but there are also risks to be aware of. Cold exposure can harm cardiovascular and pulmonary health, and the risk of hypothermia can be high as a person loses their body heat during cold swimming.
Research indicates three stages of cold water immersion and the adverse effects it can have on physiological health:
- Cold shock in the first three minutes can lead to tachycardia, cooling of the skin, and hyperventilation.
- Short-term exposure during the first 30 minutes can lead to neuromuscular cooling.
- Long-term exposure after 30 minutes can sometimes cause hypothermia, cardiac arrhythmia, and loss of consciousness.
These potential adverse health effects don’t mean you should avoid cold water swimming altogether, but they do show how important it is to assess overall health before adopting new regimens.
Cold water swimming may not be for everyone, but exploring this bracing type of exercise in a safe environment may be beneficial for you!
Featured image by Tyler Lillico on Unsplash