Cold water swimming study makes a splash

Collaborative research project between students and Wild Sea Women documented in short film

A new study has delved into the world of the Wild Sea Women, a group of cold-water swimmers, in a groundbreaking research project that tested the effects of cold-water exposure using saliva samples. This collaboration has been captured in a short film, highlighting the unique intersection of science and community.

The rise of outdoor swimming

During the global 'pandemic', many rediscovered the joys and health benefits of outdoor swimming. Public swimming pools were closed, and travel restrictions were in place, prompting people to look locally for swimming opportunities. In June 2020, the Wild Sea Women group was formed in Sunderland, starting with a small number of women eager to connect and improve their health and wellbeing through sea swimming. The group has since grown to 12,000 members across the north-east and Scotland.

Bridie Hodgson's scientific exploration

Bridie Hodgson, a final-year Biomedical Science student at the University of Sunderland and a member of Wild Sea Women, decided to investigate the biological changes experienced by cold-water swimmers. She collaborated with Dr Katrin Jaedicke, a Senior Lecturer in Applied Biosciences and an expert in salivary biomarkers, along with other final-year project students. They conducted saliva tests on the Wild Sea Women at Seaburn beach, both before and after their swims, with subsequent analysis carried out in the University’s laboratories.

Documenting the journey

The project caught the attention of north-east filmmaker Dan Prince, who documented the entire process, marking the first time cold-water exposure has been tested using saliva samples. The film captures the collaborative efforts of scientists and swimmers, showcasing their journey and the project's unique nature.

Initial findings and future research

Dr Jaedicke remarked on the enthusiasm of the participants, who willingly provided saliva samples at 6am on the beach. While the initial saliva tests did not reveal significant changes in biomarkers, the primary goal was to assess the feasibility of this type of research on a larger scale. Dr Jaedicke emphasised the importance of further investigation into the physical and mental wellbeing benefits observed in cold-water swimmers.

Bridie Hodgson plans to continue this research as part of her master’s degree, expanding the study to include more members of the Wild Sea Women from across the region and Scotland. The new study will focus on women going through menopause, examining biomarkers to better understand the relationship between environmental exposures, human biology, and disease. Additionally, the University of Sunderland’s Psychology Department will collaborate to measure psychological parameters.

Personal reflections and future aspirations

Bridie expressed her excitement about the project, stating, "This is a terrific opportunity to undertake some very fascinating work, and the University of Sunderland has allowed me to put the skills I've learned over the previous three years into practice. The Wild Sea Women made this possible, and Katrin has been an inspiring lecturer throughout my entire journey, providing endless guidance and support."

Community impact

Hayley Dorian, founder of Wild Sea Women, shared her pride in working with the University’s science team. She acknowledged the personal health benefits experienced by the group, even if the scientific evidence was not conclusive in this initial study.

Filmmaker Dan Prince reflected on the process, noting that the journey and experiences of the participants were as important as the research itself. He enjoyed capturing the contrast between the serene sea and the meticulous lab work, all centred around the shared passion for sea swimming.

This study marks a significant step in understanding the potential health benefits of cold-water swimming, paving the way for future research and collaboration.


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