Stefan Mańkowski

Sauna-Induced Body Mass Loss in Young Sedentary Women and Men

The aim of the study was to evaluate the relationship between body mass index (BMI) and body mass loss (BML) induced by thermal stress in a dry sauna. The study was conducted on a group of 674 sedentary students, 326 women and 348 men aged 19-20. The correlations between BMI scores and BML were determined. The subjects were placed in supine position in a dry sauna for two sessions of 10 minutes each with a 5-minute break. The influence of BMI on the amount of BML in the sauna was determined by nonlinear stepwise regression. The smallest BML was noted in underweight subjects; students with normal weight lost more weight, whereas the greatest BML was reported in overweight and obese subjects. Persons with a high BMI are at higher risk of dehydration, and they should pay particular attention to replenishing fluids during a visit to the sauna. The proposed equations for calculating BML based on a persons BMI can be useful in estimating the amount of fluids that should be replenished by both men and women during a visit to a dry sauna.

Socioeconomics Influences on the Water Competencies of Young Adult Polish Males

Abstract Despite the popularity of aquatic recreation and its well-promoted prophylactic and therapeutic values, not a lot is known about how socio-cultural background influences the acquisition of water competency. The aim of this study was to assess the influence of socio-economic and environmental factors on the swimming and rescue skills of male university students (n = 521) aged 19-20 years residing in the Region of Warmia and Mazury, Poland. An anonymous questionnaire was used as a diagnostic tool to elicit information on participants’ social backgrounds (such as parental income and level of education). Participants provided self-estimates of swimming and rescue competency that included non-stop distance swimming, familiarity with selected swimming strokes, and their estimated rescue ability. The results suggest that students’ self-estimated swimming competency, the distance they could swim non-stop, and the capacity to swim various strokes increased in association with higher levels of educational background of the father, higher levels of monthly income, and increased size of residential agglomeration. The level of rescue skills also improved with increases in the educational background of both parents, the size of residential agglomeration, and the monthly budget. No significant differences were found in rescue competency levels when analyzed by the mothers’ educational experience. Levels of both swimming and rescue competencies were lower than those reported in comparable studies. Socio-economic status (such as a lack of discretionary time and income for families with a lower socio-economic status) and place of residence (such as lack of facilities in small villages and towns) mediated the opportunity to acquire water competencies or gain experience with aquatic activity. Methods for addressing socio-economic barriers to the acquisition of swimming and rescue competency are discussed and recommendations for further research are made.

Sauna-induced body mass loss in physically inactive young women and men

Summary Study aim: The aim of this study was to evaluate the relationship between basic somatic features (body mass and height) and body mass loss in physically inactive young women and men exposed to thermal stress in a dry sauna. Materials and methods: The research was conducted in 2015 on 685 first-year full-time students (333 women, 352 men), aged 19–20 years old. Nude body mass was measured after the students dried off before and after using the sauna. Results: An analysis of regression equations indicated that an increase in the body mass of women and men leads to a significant increase in sauna-induced body mass loss. On the other hand, body mass loss decreased with an increase in height in women and men, but to a smaller extent. From among the tested somatic features, body height and body mass, body mass had a decisive influence on body mass loss. Body height had a minimal and statistically non-significant impact on body mass loss. Conclusions: The results of this study indicate that heavier individuals have an increased risk of dehydration and hyperthermia. Therefore, they should pay close attention to replenishing fluids lost in the sauna. The determination of body mass loss values after a visit to a dry sauna has practical significance because it supports the estimation of the fluid volume required for the maintenance of correct water balance.