Reduction in Body Weight Force at Different Levels of Immersion in a Hydrotherapy Pool - Calculation Formulas for Therapeutic Practice

Abstract

PURPOSE: Although hydrotherapy is widespread, extremely little information is available to date on the actual reduction in body weight force as a function of the patient's level of immersion. MATERIALS AND METHODS: 20 female and 14 male healthy adults (age: 21-26 years) were immersed in water at four typical immersion levels and their percentage weight-bearing value was determined using specially prepared mechanical weighing scales. The correlation between age, BMI and body fat on the one hand and relative percentage weight-bearing value on the other hand was examined. RESULTS: Percentage weight-bearing values investigated separately for males and females were as follows for the four immersion levels: popliteal fossa, 88.1±2.3 and 86.7±1.9; anterior superior iliac spine (ASIS) 59.1±4.4 and 52.5±4.9, xiphisternum 35.3±3.3 and 31.6±2.7 and sternoclavicular articulation 11.8±1.9 and 10.2±3.2. Where B = body fat in % and W=body weight on land in Newtons, the following results for percentage weight-bearing value (y) were determined at the three most relevant depths. For immersion up to the sternoclavicular joint y ART =[14.23-(0.19·B)]·W/100, immersion to the xiphisternum y XIPH =[39.42-(0.34·B)]·W/100 and immersion up to the anterior superior iliac spine (ASIS) y ASIS =[65.02-(0.52·B)]·W/100. CONCLUSIONS: This study is the first to provide data on reduction in body weight force at typical levels of immersion in hydrotherapy as a function of gender and body fat and as such provides a gooda basis for planning this rehabilitation process.