Measures of heart rate variability (HRV) are a reliable reflection of the many physiological factors modulating the normal rhythm of the heart.  In fact, they provide a powerful means of  observing the interplay between the sympathetic and parasympathetic nervous systems.  A growing number of studies indicate that increased variability in the heart's interbeat interval is physiologically desirable. CardioPro is a specialized biofeedback application that provides a sophisticated array of feedback tools for monitoring HRV and Respiratory Sinus Arrhythmia (RSA); it is an effective adjunct to any relaxation and self-regulation training program. Real-time audio and visual feedback on the standard deviation of the IBI provides an immediate indication of changes in heart rate variability. A programmable respiration pacer allows the user to define breathing cycles that include inspiration and expiration time as well as breath holding pauses.   The Statistical Report printout of standard calculations includes power analysis for the LF, HF and VLF components of the HRV spectrum, SDNN, NN50 and PNN50.   CardioPro's export function for the IBI data ensures compatibility with third-party data analysis software packages. A true 32-bit Windows™ application, CardioPro offers the best combination of user-friendly graphical interface and powerful features to make it the most competitive software package available for respiration, RSA/HRV biofeedback and research. Selling points of CardioPro