Borbély, A. (2022). The two-process model of sleep regulation: Beginnings and outlook. Journal of Sleep Research, 31, e13598. https://doi.org/10.1111/jsr.13598

Article  Google Scholar 

Buysse, D. J., Reynolds, C. F., 3rd., Monk, T. H., et al. (1989). The Pittsburgh Sleep Quality Index: A new instrument for psychiatric practice and research. Psychiatry Research, 28, 193–213. https://doi.org/10.1016/0165-1781(89)90047-4

Article  Google Scholar 

Carnethon, M. R., Evans, N. S., Church, T. S., et al. (2010). Join associations of physical activity and aerobic fitness on the development of incident hypertension: Coronary artery risk development in young adults. Hypertension, 56, 49–55. https://doi.org/10.1161/HYPERTENSIONAHA.109.147603

Article  Google Scholar 

Castelli, L., Ciorciari, A. M., Galasso, L., Mulè, A., Fornasini, F., Montaruli, A., Roveda, E., & Esposito, F. (2024). Revitalizing your sleep: The impact of daytime physical activity and balneotherapy during a spa stay. Frontiers in Public Health, 12, 1339689. https://doi.org/10.3389/fpubh.2024.1339689. eCollection 2024.

Article  Google Scholar 

Cheng, P., Tallent, G., Bender, T. J., et al. (2017). Shift work and cognitive flexibility: Decomposing task performance. Journal of Biological Rhythms, 32, 143–153. https://doi.org/10.1177/0748730417699309

Article  Google Scholar 

Dai, Y., Chen, B., Chen, L., et al. (2023). Insomnia with objective short sleep duration is associated with hypertension. Journal of Sleep Research, 32, e13833. https://doi.org/10.1111/jsr.13833

Article  Google Scholar 

Doi, Y., Minowa, M., Uchiyama, M., et al. (2000). Psychometric assessment of subjective sleep quality using the Japanese version of the Pittsburgh Sleep Quality Index (PSQI-J) in psychiatric disordered and control subjects. Psychiatry Research, 97, 165–172. https://doi.org/10.1016/s0165-1781(00)00232-8

Article  Google Scholar 

Flexer, A., Gruber, G., & Dorffner, G. (2005). A reliable probabilistic sleep stager based on a single EEG signal. Artificial Intelligence in Medicine, 33, 199–207. https://doi.org/10.1016/j.artmed.2004.04.004

Article  Google Scholar 

Forman, J. P., Stampfer, M. J., & Curhan, G. C. (2009). Diet and lifestyle risk factors associated with incident hypertension in women. JAMA, 302, 401–411. https://doi.org/10.1001/jama.2009.1060

Article  Google Scholar 

Fukuhara, S., Bito, S., Green, J., Hsiao, A., & Kurokawa, K. (1998). Translation, adaptation, and validation of the SF-36 health survey for use in Japan. Journal of Clinical Epidemiology, 51, 1037–1044. https://doi.org/10.1016/s0895-4356(98)00095-x

Article  Google Scholar 

Gudberg, C., Stevelink, R., Douaud, G., Wulff, K., Lazari, A., Fleming, M. K., & Johansen-Berg, H. (2022). Individual differences in slow wave sleep architecture relate to variation in white matter microstructure across adulthood. Frontiers in Aging Neuroscience, 14, 745014. https://doi.org/10.3389/fnagi.2022.745014. eCollection 2022.

Article  Google Scholar 

Haghayegh, S., Khoshnevis, S., Smolensky, M. H., Diller, K. R., & Castriotta, R. J. (2019). Before-bedtime passive body heating by warm shower or bath to improve sleep: A systematic review and meta-analysis. Sleep Medicine Reviews, 46, 124–135. https://doi.org/10.1016/j.smrv.2019.04.008

Article  Google Scholar 

Hayasaka, S., Shibata, Y., Goto, Y., et al. (2010). Bathing in a bathtub and health status: A cross-sectional study. Complementary Therapies in Clinical Practice, 16, 219–221. https://doi.org/10.1016/j.ctcp.2010.05.002

Article  Google Scholar 

He, F. J., Li, J., & Macgregor, G. A. (2013). Effect of longer term modest salt reduction on blood pressure: Cochrane systematic review and meta-analysis of randomised trials. BMJ (Clinical Research Ed.), 346, f1325. https://doi.org/10.1136/bmj.f1325

Article  Google Scholar 

Hisamatsu, T., Segawa, H., Kadota, A., Ohkubo, T., Arima, H., & Miura, K. (2020). Epidemiology of hypertension in Japan: Beyond the new 2019 Japanese guidelines. Hypertension Research, 43, 1344–1351. https://doi.org/10.1038/s41440-020-0508-z

Article  Google Scholar 

Kanda, Y. (2013). Investigation of the freely available easy-to-use software “EZR” for medical statistics. Bone Marrow Transplantation, 48, 452–458. https://doi.org/10.1038/bmt.2012.244

Article  Google Scholar 

Kim, K., Uchiyama, M., Okawa, M., et al. (2000). An epidemiological study of insomnia among the Japanese general population. Sleep, 23, 41–47.

Article  Google Scholar 

Koçak, F. A., Kurt, E. E., MilletliSezgin, F., et al. (2020). The effect of balneotherapy on body mass index, adipokine levels, sleep disturbances, and quality of life of women with morbid obesity. International Journal of Biometeorology, 64, 1463–1472. https://doi.org/10.1007/s00484-020-01924-x

Article  Google Scholar 

Lakens, D. (2013). Calculating and reporting effect sizes to facilitate cumulative science: A practical primer for t-tests and ANOVAs. Frontiers in Psychology, 4, 863. https://doi.org/10.3389/fpsyg.2013.00863

Article  Google Scholar 

Latorre-Román, P. Á., Rentero-Blanco, M., Laredo-Aguilera, J. A., et al. (2015). Effect of a 12-day balneotherapy programme on pain, mood, sleep, and depression in healthy elderly people. Psychogeriatrics, 15, 14–19. https://doi.org/10.1111/psyg.12068

Article  Google Scholar 

Maeda, S., Nakanishi, S., & Kohno, N. (2013). Relationship between bathing habits and the serum lipid profile among Japanese-Americans. Journal of Atherosclerosis and Thrombosis, 20, 830–832. https://doi.org/10.5551/jat.18069

Article  Google Scholar 

Mander, B. A., Winer, J. R., & Walker, M. P. (2017). Sleep and human aging. Neuron, 94, 19–36. https://doi.org/10.1016/j.neuron.2017.02.004

Article  Google Scholar 

Mishima, Y., Hozumi, S., Shimizu, T., et al. (2005). Passive body heating ameliorates sleep disturbances in patients with vascular dementia without circadian phase-shifting. The American Journal of Geriatric Psychiatry, 13, 369–376. https://doi.org/10.1176/appi.ajgp.13.5.369

Article  Google Scholar 

MoiniJazani, A., NasimiDoostAzgomi, H., NasimiDoostAzgomi, A., & NasimiDoostAzgomi, R. (2023). Effect of hydrotherapy, balneotherapy, and spa therapy on blood pressure: A mini-review. International Journal of Biometeorology, 67, 1387–1396. https://doi.org/10.1007/s00484-023-02512-5

Article  Google Scholar 

Nozato, Y. (2025). Hypertension research 2024 update and perspectives: Blood pressure management. Hypertension Research, 48, 1733–1738. https://doi.org/10.1038/s41440-025-02130-1

Article  Google Scholar 

Ohayon, M. M., Carskadon, M. A., Guilleminault, C., et al. (2004). Meta-analysis of quantitative sleep parameters from childhood to old age in healthy individuals: Developing normative sleep values across the human lifespan. Sleep, 27, 1255–1273. https://doi.org/10.1093/sleep/27.7.1255

Article  Google Scholar 

Porges, S. W. (2022). Polyvagal theory: A science of safety. Frontiers in Integrative Neuroscience, 16, Article 871227. https://doi.org/10.3389/fnint.2022.871227. eCollection 2022.

Article  Google Scholar 

Sawatari, H., Nishizaka, M. K., Miyazono, M., et al. (2018). Three nights leg thermal therapy could improve sleep quality in patients with chronic heart failure. Heart and Vessels, 33, 155–162. https://doi.org/10.1007/s00380-017-1047-7

Article  Google Scholar 

Sella, E., Toffalini, E., Canini, L., & Borella, E. (2023). Non-pharmacological interventions targeting sleep quality in older adults: A systematic review and meta-analysis. Aging & Mental Health, 27, 847–861. https://doi.org/10.1080/13607863.2022.2056879

Article  Google Scholar 

Tai, Y., Saeki, K., Yamagami, Y., et al. (2019). Association between timing of hot water bathing before bedtime and night-/sleep-time blood pressure and dipping in the elderly: A longitudinal analysis for repeated measurements in home settings. Chronobiology International, 36, 1714–1722. https://doi.org/10.1080/07420528.2019.1675685

Article  Google Scholar 

Tai, Y., Obayashi, K., Yamagami, Y., et al. (2021). Hot-water bathing before bedtime and shorter sleep onset latency are accompanied by a higher distal-proximal skin temperature gradient in older adults. Journal of Clinical Sleep Medicine, 17, 1257–1266. https://doi.org/10.5664/jcsm.9180

Article  Google Scholar 

Uemura, S. I., Kanbayashi, T., Ito, W., et al. (2023). Changes in sleep profile on exposure to sodium chloride and artificially carbonated springs: A pilot study. Journal of Physical Therapy Science, 35, 330–339. https://doi.org/10.1589/jpts.35.330

Article  Google Scholar 

Wang, M., Yang, M., Liang, S., Wang, N., Wang, Y., Sambou, M. L., Qin, N., Zhu, M., Wang, C., Jiang, Y., & Dai, J. (2024). Association between sleep traits and biological aging risk: A Mendelian randomization study based on 157227 cases and 179332 controls. Sleep, 47, zsad299. https://doi.org/10.1093/sleep/zsad299

Article  Google Scholar 

Whelton, P. K., Carey, R. M., Aronow, W. S., et al. (2018). 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: A report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Hypertension, 71, e13–e115. https://doi.org/10.1016/j.jacc.2017.11.006

Article  Google Scholar 

Wickwire, E. M., Geiger-Brown, J., Scharf, S. M., et al. (2017). Shift work and shift work sleep disorder: Clinical and organizational perspectives. Chest, 151, 1156–1172. https://doi.org/10.1016/j.chest.2016.12.007

Article  Google Scholar 

Yagi, A., Hayasaka, S., Ojima, T., Sasaki, Y., Tsuji, T., Miyaguni, Y., Nagamine, Y., Namiki, T., & Kondo, K. (2019). Bathing frequency and onset of functional disability among Japanese older adults: A prospective 3-year cohort study from the JAGES. Journal of Epidemiology, 29, 451–456. https://doi.org/10.2188/jea.JE20180123

Article  Google Scholar 

Yamasaki, S., Tokunou, T., Maeda, T., & Horiuchi, T. (2022). Hot spring bathing is associated with a lower prevalence of hypertension among Japanese older adults: A cross-sectional study in Beppu. Scientific Reports, 12, 19462. https://doi.org/10.1038/s41598-022-24062-3

Article  Google Scholar