PLoS One. 2026 Sep 8;21(9):e0353797. doi: 10.1371/journal.pone.0353797. eCollection 2026.
ABSTRACT
BACKGROUND: Passive heat therapy (HT), such as hot water immersion (HWI), has emerged as a non-exercise health-promoting intervention. Epidemiological data demonstrate that HT engagement reduces cardiovascular disease risk, however, experimental protocols are often time intensive and perceived as uncomfortable. This study explored the expectations, perceptions and anticipated uptake of HT in response to an acute HWI session.
METHODS: Twenty young, healthy, recreationally active males completed a 60-min HWI protocol (39°C) separated by bespoke pre- and post-immersion surveys.
RESULTS: Before immersion, most participants agreed HWI would be easy to complete (90%) and relaxing (85%). Despite reported thermal discomfort during immersion, post-immersion, most participants perceived HWI as enjoyable (60%) and relaxing (65%), although 50% also agreed HWI was more challenging and less enjoyable than expected. Participants indicated that if given autonomy during HWI, the average self-selected duration would have been 31 ± 13 min. Assuming access, the anticipated weekly future engagement with HT was 49 ± 31 min, with 15% of participants indicating they would select HT over walking to improve their health. Time availability emerged as the most influential factor, with all participants agreeing this would impact future engagement.
CONCLUSIONS: Although there were positive perceptions of HWI, thermal discomfort and time requirements may limit the uptake of HT as a health-promoting intervention. These findings highlight a discrepancy between the duration of commonly employed HT experimental protocols and what individuals appear realistically willing or able to complete. Future HT research should prioritise acceptability and accessibility by developing time-efficient and thermally tolerable protocols.
PMID:42709729 | DOI:10.1371/journal.pone.0353797