Rate Pressure Product as a Determinant of Physical Fitness in Normal Young Adults

Rate Pressure Product (RPP) is a valuable marker of cardiac function.It is the product of heart rate (HR) and systolic blood pressure (SBP) (HR x SBP/1000). RPP up to 12 at rest and up to 22 in stressed conditions is considered as normal. This study deals with RPP evaluation in60 young normal subjects of 18 to 22 years old (30 males and 30 females).HR and SBP were recorded before and after 5 min of mental stress (mental arithmetic) and physical stress (cycling) from which RPP was calculated.RPP increased significantly after mental stress in both the genders (males (M) p< 0.0001 and females (F) p< 0.0005). But there was no gender difference in the level of increase. After physical stress also RPP increased in males significantly (p<0.0004)and in females non-significantly (p<0.143).Determination of RPP is the best non-invasive and time sparing method of assessing the functional status of heart. It is controlled by autonomic nervous system (ANS) through HR and SBP. Increase in RPP under stressed condition implies the normal buffering function of ANSand good coronary perfusion. In the present study, RPP increased significantly in males and nonsignificantly in females after physical stress, implying that ANS buffering function is better in males than in females. We conclude that RPP is a good index to assess cardiovascular competency in stress which may help to determine the intensity and duration of exercise in developing physical fitness and in patient-care without overloading the heart.