Relation between sauna-induced dehydration and physiological and thermal parameters in young volunteers: preliminary data

BACKGROUND: Despite both the crucial importance of hydration and recent advances on wearable electronics, no portable systems for monitoring the hydration status are available, mainly due to insufficient insight into the complex relations between hydration and physiological parameters. Therefore, we investigated the effect of controlled dehydration and hydration on several key physiological parameters.METHODS: Twelve healthy volunteers (53% males, aged 30.4 +/- 1.3 years) were included in this study; their weight, oxygen saturation, heart rate, systolic and diastolic pressure, axillary temperature taken with medical devices and multiple temperatures taken with a thermal camera were collected at baseline, after dehydration in Finnish sauna followed by 10 minutes-acclimatization, and 30 minutes after controlled oral rehydration (750 cc of water) without urinating.RESULTS: In particular, these measurements showed significant differences in most of the examined physiological parameters between the three assessment times, and findings of particular interest regarding the thermal parameters.CONCLUSIONS: These results provide insight both on the relations between hydration and physiological parameters and for designing portable systems for monitoring hydration