The health benefits of wild swimming

March 29, 2023

New studies and research have now given greater scientific insight into how icy-water swimming, cold showers, ice baths and exposure to cooler water and air temperatures might drive health benefits.

James Mercer, PhD, a thermal physiology specialist from UiT who led the new research, says that many small studies over the years have hinted at the benefits of cold-water immersion. But the new review is one of the most comprehensive assessments of the benefits of cold-water swimming, bathing, showering and therapies based on exposing the body to low temperatures.

“It’s very rare that you’ll meet a cold-water swimmer who thinks it’s a negative activity. They all swear by it,” Mercer says. Over the years there has been evidence that cold-water swimming can boost your health, Mercer says. This includes everything from increased libido to improved heart health, mental health and more. 

Additional findings:

  • Some studies showed solid evidence that cold-water swimmers often experience significant improvements in overall cardiovascular health.
  • Cold-water immersion triggers a “shock response” that stresses the cardiovascular system and elevates the heart rate — a chief goal of high-intensity heart-healthy exercise.
  • Ice baths and other hydrotherapies can reduce cholesterol, boost the immune system, help treat autoimmune inflammation, ease pain and speed recovery from sports injuries.
  • Cold-water swimming boosts the body’s stores of so-called “brown adipose tissue” (BAT), a type of “good” body fat activated by low temperatures. BAT burns calories to maintain body heat, which can lead to weight loss, unlike “bad” white fat which stores energy and hikes obesity risks.
  • Exposure to cold water or air boosts BAT’s production of adiponectin, a protein that helps protect against insulin resistance, diabetes and other diseases. 
  • Cold-water immersions greatly increase insulin sensitivity and decrease insulin concentrations. This is true for both inexperienced and experienced swimmers. 
  • Winter-weather swimmers typically describe feeling “joyful” in the water, suggesting the practice has “a positive effect on mental health and brain development.”

The researchers note the participants in the 104 studies analysed, varied widely. They ranged from elite swimmers and regular winter bathers to those with no previous winter swimming experience. Others were not strictly ice bathers but used cold-water immersion as a treatment after exercise. 

They added that other factors — beyond cold-water exposure — may play a role in the health benefits. For instance, cold-water swimmers may be ‘naturally healthier’ as a group and tend to live active lifestyles. They experience positive social interactions from such activities, have learned how to handle stress (often through meditation, breathing techniques and mindfulness practices), eat healthy foods and demonstrate ‘a positive mindset’.