The Heartwood Review / Traditional sauna
Peer-reviewed studies on traditional and Finnish sauna bathing: cardiovascular outcomes, recovery, sleep, mood, and long-term cohort findings. 13 entries, newest first. Every entry links to its source.
A modest-sized single-protocol trial of 27 participants, this study offers some of the clearest evidence to date that men and women converge on similar heat adaptation outcomes despite starting from different physiological baselines.
Journal of applied physiology (Bethesda, Md. : 1985), 2025 · Giersch et al.
Modest-sized single-cohort study of 42 young adults; findings may not extend to older adults, clinical populations, or passive heat exposures such as sauna.
Physiological reports, 2026 · Brazelton et al.
This well-controlled comparative trial (n = 60, equal male/female split) suggests that how heat exposure is scheduled across a day matters for adaptation, though the environment used was humid exercise rather than a traditional sauna.
Physiological reports, 2026 · Rosales et al.
A small crossover trial of 22 trained male cyclists suggests the overall heat stimulus matters more than whether the air is dry or humid, though the modest sample and single-sex design limit how broadly these findings apply.
The Journal of physiology, 2026 · McDonald et al.
A small but carefully instrumented controlled trial of 31 participants found that older adults retained the same neural plasticity for heat adaptation as younger adults, though the short duration and single-site design limit how broadly the results can be applied.
The Journal of physiology, 2026 · Deshayes et al.
Promising early evidence, but the trial was small (18 participants, 9 per group) and limited to active young men, so how broadly these adaptations apply remains an open question.
Journal of applied physiology (Bethesda, Md. : 1985), 2026 · Dunn et al.
A descriptive survey of 588 adults, this study captures perceived benefits and motivations but cannot confirm that sauna bathing causes any of the health outcomes participants reported.
International journal of circumpolar health, 2026 · Engström et al.
This large, long-running observational study cannot establish causation, and its findings apply specifically to middle-aged Finnish men, limiting how broadly the results can be generalized.
Scandinavian cardiovascular journal : SCJ, 2024 · Kunutsor SK et al.
Because this is an observational snapshot rather than a controlled experiment, it cannot establish that sauna use caused these differences; the findings come from a large regional sample of 971 adults but reflect associations only.
International journal of circumpolar health, 2024 · Engström Å et al.
This null finding on the sauna-plus-exercise combination is the headline result, though the trial was small (38 participants across three arms) and limited to a specific sedentary, at-risk population over eight weeks.
Physiological reports, 2025 · Lee et al.
A narrative review of 45 studies, this synthesis is useful context but cannot establish causation, and its conclusions are shaped by the uneven quality of the underlying literature.
International journal of environmental research and public health, 2026 · Nagai et al.
A well-designed single-site trial of 50 participants, this study adds meaningful nuance to how sauna conditions are characterized, though its acute, short-session design limits conclusions about longer-term health outcomes.
Temperature (Austin, Tex.), 2026 · Laatikainen-Raussi I et al.
A large multi-study programme (N = 1,907), but all findings rest on self-report and observational methods, so causal claims about sauna causing wellbeing improvements are not supported.
Social science & medicine (1982), 2026 · Newson et al.