The systems and methods monitor a subject's blood pressure under a constant applied pressure. Measurements taken from a pressure measuring element and a pulse sensing element are combined to determine the subject's systolic and diastolic pressure. The systolic pressure is measured directly by the pressure measuring element, and the diastolic pressure is determined indirectly by using a pulse waveform to extrapolate portions of a pressure waveform. The systems and methods can be employed in any number of applications, including, without limitation, taking a single reading from a subject, continuously monitoring a subject, or evaluating a subject during physical exertion.