The PHA Registry is excited to support the “Physical Activity in Pulmonary Arterial Hypertension” (ACTiPH) ancillary study, funded by the National Institutes of Health. Steven Kawut, M.D., from the University of Pennsylvania is the principal investigator. ACTiPH will perform activity monitoring on adult and pediatric participants in PHAR with accelerometers every six months to determine whether physical activity is associated with outcomes in PH. Five pilot sites are preparing to initiate the study, including the University of Pennsylvania, Rhode Island Hospital/Brown University, INOVA, University of Colorado and Stanford University. Eventually, all active PHAR centers which are active will be eligible to participate. Centers and participants will be reimbursed on a pro-rated basis.