Embodiments provide physiological measurement systems, devices and methods for continuous health and fitness monitoring. A wearable strap may automatically and continually sense and collect data corresponding to the heart rate of a user, which may then be used to determine cardiovascular intensity experienced by the user. Specifically, the heart rate data may be transformed into a time series of heart rate reserve data which is then weighted according to a weighting scheme. The weighted heart rate reserve data may be the basis for programmatically generating an indicator of cardiovascular intensity experienced by the user, which is displayed for a user on the user interface of a display device.
