WestIndianMedJ2011;60(2):148 ImpactofYogaonHaemodynamicFunctioninHealthyMedicalStudents O Parshad 1 ,ARichards 1 ,MAsnani 2 ABSTRACT Objectives: Yogaimprovescardiovascularhealthinbothhealthyindividualsandthosewithdiagnosed heart disease. This study compares changes in some cardiovascular parameters before and after the practiceofYogainhealthymedicalstudents. Methods: Sixty-four healthy medical students (57 females and 7 males), mean age 21.3 ±2.6 years, attending a Special Study Module ‘Role of Dhyana Yoga in Stress Management’, participated in this study. Systolic (SYS) and Diastolic (DIA) blood pressure, Heart Rate (HR), Stroke Volume (SV), Cardiac output (CO), Total Peripheral Resistance (TPR), Interbeat Interval (IBI), Left Ventricular Ejection Time (LVET), Arterial Compliance (Cwk) and Ascending Aorta Impedance (Zao) were measuredbeforeandaftersixweeksofyogicexercises. Variousexercisesincluded asanas (Postures), pranayama (Breathing),and dhyana (Meditation). DatawereanalyzedusingStataforWindows TM . Results: Two-tailedpairedt-testrevealedthatpracticeofyogacausedsignificantincreasesinHR(p < 0.05),SV(p <0.01),CO(p <0.001)andCwk(p <0.01)anddecreasesinTPR(p <0.001),IBI(p < 0.05)andZao(p <0.001)afterpractisingyogafor6weeksascomparedtobeforeyogapractice. No significantdifferenceswere,however,observedinSYS,DIA,Meanarterialbloodpressure(MAP)and LVET. Conclusions: Practice of yoga even for a short period showed ability to improve most of the cardiovascular functions. Regular practice of yoga for a longer period may further improve these functionsandpossiblyresultinimprovedmanagementoftheirdailystress. Keywords: Healthy adults, haemodynamics, yoga ImpactodelYogaenlaFunciónHemodinámicadeEstudiantesde MedicinaSaludables O Parshad 1 ,ARichards 1 ,MAsnani 2 RESUMEN Objetivos: El yoga mejora la salud cardiovascular tanto en individuos sanos como aquellos con diagnóstico de enfermedad cardíaca. Este estudio compara cambios en algunos parámetros cardio- vascularesantesydespuésdelaprácticadelyogaenestudiantesdemedicinasaludables. Métodos: Sesentaycuatroestudiantesdemedicina saludables(57mujeresy7hombres),conunaedad promediode21,3±2.6años,queasistíanaunmóduloespecialdeestudio“PapeldeDhyanaYogaen elmanejodelestrés”,participaronenesteestudio. Antesydespuésdeseissemanasdeejerciciosyoga, semidieronlapresiónarterialsistólica(SIS)ydiastólica(DIA),ritmocardíaco(RC),volumensistólico de eyección (VS), gasto cardíaco (GC), resistencia periférica total (RPT), tiempo de intervalos interpulsos o interlatidos cardiacos (IBI), tiempo de eyección ventricular izquierda (TEVI), distensibilidadarterialWindkessel(Cwk)ylaimpedanciadelaaortaascendente(Zao). Losdiversos ejerciciosincluyeron asanas (posturas), pranayama (respiración)y dhyana (meditación). Seanalizaron losdatosusandoStatadeWindows. Resultados: LapruebaTpareadodedoscolas,revelóquelaprácticadelyogacausaba importantes aumentosdelRC(p <0,05),VS(p <0,01),GC(p <0,001)yCwk(p <0,01)ydisminucionesdeRTP From: 1 Department of Basic Medical Sciences, and 2 Sickle Cell Unit, Tropical Medicine Research Institute, The University of the West Indies, Kingston7,Jamaica,WestIndies. Correspondence: Dr M Asnani, Sickle Cell Unit, Tropical Medicine Research Institute, The University of the West Indies, Kingston 7, Jamaica, West Indies. Fax: (876) 927-2984, e-mail: monika.parshadasnani@ uwimona.edu.jm