by Olivia Barnes
The Physiological Society hosted a conference on “Thermal Physiology in Health and Disease: Mechanisms and Therapeutic Applications” on the 3rd and 4th of June 2025, at Brunel University of London. The scope of the meeting encompassed the increasing severity of thermal stress experienced by individuals through acceleration of climate change and subsequent occurrence of heat waves. Acknowledgement was placed on advancing mechanistic understanding of the influence thermal stress imposes on physiological systems and the growing relevance of heat illness mechanisms on both vulnerable, and otherwise healthy populations.
Dr. Jessica Mee (Research Fellow, FHL) delivered an invited talk exploring the critical, yet often overlooked, sex-specific differences in thermal physiology. Jessica’s presentation, titled “Sex Specific Considerations in Thermal Physiology”, focused on the biological and hormonal factors influencing females’ responses to heat stress, highlighting a vital dimension of climate resilience.
Key insights from Jessica’s talk included:
- Greater Thermal Strain in Females: Women may experience higher levels of heat strain than men, largely due to a lower sweating capacity, especially under intense thermal stress. This can delay the body’s ability to cool itself effectively.
- Hormonal Influence Across the Menstrual Cycle: Elevated progesterone during the luteal phase raises core body temperature and delays the onset of cooling responses like sweating and skin blood flow. These hormonal shifts can reduce heat tolerance at certain points in the cycle.
- Impact of Menopause and Perimenopause: Women experiencing menopausal transitions often report increased thermal discomfort, with hot flushes and night sweats exacerbating heat-related symptoms and disrupting daily life.
- Challenges in Heat Adaptation: Females may need longer acclimatisation periods than males. Additionally, societal roles—such as caregiving responsibilities—can make it harder for women to adapt routines or seek relief during heat waves.
Jessica additionally emphasised the underrepresentation of females in heat stress research during her talk. She challenged the pressing issue and gap in current research, arguing it stems from the difficulty associated with accounting for hormonal variability. She highlighted that to continue ignoring these factors risks incomplete or misleading conclusions about human vulnerability to heat.
Her talk concluded with a call to action: As heatwaves become more frequent and intense, incorporating sex-specific data into public health planning and climate resilience strategies will be essential to ensure interventions are inclusive, effective, and equitable.
Reflecting on the event, Jessica said “Attending the Thermal Physiology in Health and Disease conference was a wonderful opportunity to connect with researchers from around the UK and beyond, all united by a shared focus on thermal physiology. The event featured an impressive lineup of speakers whose deep expertise enriched every session, creating a truly vibrant and dynamic atmosphere. It was a genuine privilege to be invited to present among such a passionate, insightful group and being involved in thought-provoking discussions.”
Olivia Barnes (Research Associate, FHL) presented her latest research at the conference, shedding light on how vulnerable adults in the UK experience and manage heat waves. Her presentation, titled “Preparing for a Heat Wave and Perceived Heat Illness Symptoms During a Heat Wave in the UK: Insights from Vulnerable Adults”, explored how prepared people feel to experience extreme heat and the associated health impacts they encounter during such events.
Oliva’s study surveyed over 200 UK residents following the July 2024 heat wave, which met official heat wave temperature thresholds and durations across most UK regions, and reached peak temperatures of 32°C. Participants included a broad demographic of individuals, with many respondents reporting clinical condition diagnoses, mental health diagnoses, or being over age 65.
Key findings from her presentation included:
- Lack of Education: Few participants had accessed or were provided educational materials surrounding preparing and staying safe during heat waves – only 12% of health participants and less than 11% of vulnerable participants had encountered relevant information from their employer or Public Health England.
- Health Impacts: Vulnerable participants commonly reported experiencing heat-related illness symptoms during extreme heat exposure, such as fatigue, sweating, light-headedness and feeling thirsty. For example, 100% of participants with a clinical health condition and 97% of participants aged over 65 reported experiences of at least one symptom.
- High Willingness to Prepare: Despite the reported lack of education, 96% of participants expressed willingness to adopt at least one heat mitigation strategy in the future to adapt and manage the heat more effectively. Popular strategies included regularly taking hot baths, saunas, using fans and taking regular breaks.
In Olivia’s presentation she emphasised that although people are increasingly aware of the associated risks during extreme heat and there is willingness to better prepare for heat waves, the educational outreach via employers and public health organisations are falling short. Her research calls for improved distribution of educational materials and support to enable people to stay safe in the heat.
Reflecting on the event, Olivia said “As an early career researcher, attending and presenting at the conference was a fantastic, immersive experience to assist my professional development. It was enlightening to listen to the multitude of avenues researchers are steering thermal physiology investigations and the impact they hope their work will impose. The interest and support received from fellow attending society members following my presentation reinforced the importance of expanding research in the implications of climate change and heat health, as well as greatly enhancing my experience at my first conference event.”
