Cold water swimming: panacea or peril?
Cold plunges and cold water swimming are increasingly popular, with big benefit claims being made on social media. But is submerging yourself in frigid water actually good for you? Claire Concannon joins a team of researchers at the 2026 New Zealand and Oceania Ice Swimming Championships in Alexandra as they try to get some better data about both the risks and potential benefits. Sign up to the Our Changing World monthly newsletter for episode backstories, science analysis and more. IN THIS EPISODE: (00:00) Introduction – the rise of cold water swimming. (01:06) The 2026 New Zealand and Oceania Ice Swimming Championships in Alexandra. (02:00) Competitor Susan Sherwen on why she ice swims. (05:10) How researchers track swimmers’ core temperature, stroke rate and perceptions of cold. (07:30) Prof Jim Cotter on cold shock, hypothermia and afterdrop. (12:00) The recovery room – Steven and Susan after their swim. (17:30) Potential benefits and what the research says. (20:30) Blood samples and looking for brain health proteins. (23:40) Potential mental health benefits… Go to this episode on rnz.co.nz for more details