Correlations between Repeated Use of Dry Sauna for 4 x 10 Minutes, Physiological Parameters, Anthropometric Features, and Body Composition in Young Sedentary and Overweight Men: Health Implications.
Level 4 - case-series / case-control
Single-arm pre-post interventional study without a control group
PubMed 30800676 · doi:10.1155/2019/7535140
What was done
Forty-five sedentary, overweight men (mean age 20.76 ± 2.4 years) underwent four 10-minute Finnish sauna sessions (90–91°C, 14–16% relative humidity) separated by 5-minute cool-down breaks. Body composition was assessed before the protocol, while body mass and blood pressure were measured before and after. Physiological parameters (heart rate, energy expenditure, blood pressure) were monitored during the sessions and evaluated for correlations with baseline anthropometric and body composition parameters.
What was found
A significant increase occurred in all analyzed physiological parameters across the four sessions (p < 0.0001). Heart rate, energy expenditure, blood pressure, and body mass loss were most strongly correlated with body mass, body mass index, body surface area, percent body fat, body fat mass, and visceral fat level. The 60-minute protocol resulted in a significant reduction in body mass of 0.65 kg. Specific numeric values for heart rate, blood pressure, and correlation coefficients were not reported in the abstract.
Why it matters
This study demonstrates that repeated acute sauna exposure causes progressive cardiovascular strain in sedentary overweight young men, with the greatest strain observed in individuals with higher body mass and adiposity.
Limits
The study lacked a control group of normal-weight or physically active individuals. The sample was modest (n = 45) and restricted entirely to young men, limiting generalizability to women or older adults. Only acute immediate responses were measured, and exact baseline or peak cardiovascular values were omitted from the abstract.