Comparative Study on the Effects of Health Promotion of Single Bathing and 200m Running

Purpose<br> The effects of 10 min bathing at 41°C and 200 m/1.2min running inducing similar tachycardic response were examined comparatively on cardiovascular functions, blood gas and tissue metabolism, and peripheral blood compositions.<br>Subjects and Methods<br> The subjects examined were 13 healthy males (28.7±3.6 yrs). They kept rest for 30min before bathing and running study and measurements of blood pressure (BP), heart rate (HR), sublingual temperature and skin blood flow and a indwellng catheter for blood sampling in cubital vein were performed. The subjects had 41°C bathing for 10 min and 200 m running/1.2 min (10km/hr) separately which induced the increase in heart rate by 30bpm in preliminary study. Measurements and blood sampling were done just after the loading (bathing or running) and 15min after the loading.<br>Results and Discussion<br> The increase in HR just after bathing and running were nearly the same level, 27 and 25 bpm, respectively. The increase in systolic BP after running was greater than that after bathing, and diastolic BP was significantly reduced after bathing from resting level. Sublingual temperature and skin blood flow were increased only after bathing suggesting the marked thermal vasodilation.<br> After bathing, venous pO₂ was significantly increased and pCO₂ was significantly decreased, and there were no significant changes in lactate and pyruvate level. On the contrary, after 200 m running, venous pO₂ was decreased and pCO₂ was increased, and blood lactate, pyruvate and P/L ratio were significantly increased. These changes show that bathing provides tissue full oxygenation and washout of CO₂ by increased blood supply without metabolic activation. After running, increased glycolysis in muscle and delayed oxidation by TCA cycle were suggested.<br> As the increase in WBC after bathing (+6%) and exercise (+22%) subsided very shortly., these changes might be explained by mixing perivascular flow enriched with leucocytes and central flow enriched with plasma due to increased circulation. Previous reports on the change of lymphocyte subsets after bathing and exercise should be examined from this viewpoint. The role of plasma concentration estimated from the changes in RBC and plasma protein was relatively low, around 2% by bathing and 4% by running.<br>Conclusion<br> Health promotion by bathing seems to be conducted through sufficient O₂ supply and washout of CO₂ by thermal vasodilation without metabolic activation. Health promotion by exercise is induced by strong activation of cardiovascular and muscle metabolic function. Combination of passive effects by bathing and active exercise will be favorable for balanced health promotion.