A monitoring device configured to be attached to a subject, the monitoring device comprising: a sensor configured to detect and/or measure physiological parameters from the subject, wherein the sensor comprises at least one optical emitter and at least one optical detector; and a processor coupled to the sensor and configured to receive and analyze signals produced by the sensor, and wherein the processor is configured to instruct the at least one optical emitter to emit a different wavelength of light during each of a series of respective time intervals such that a respective one of a plurality of different physiological parameters can be measured from the subject during each of the respective intervals via the at least one optical detector, wherein the processor is configured to: control the sensor to emit light at a first wavelength during a first time interval and to detect the light at the first wavelength according to a first polling rate; receive and analyze signals produced by the sensor during the first time interval to determine a heart rate of the subject; control the sensor to emit light at a second different wavelength during a second different time interval and to detect the light at the second wavelength according to a second different polling rate; and receive and analyze signals produced by the sensor during the second time interval to determine a blood pressure of the subject. a sensor configured to detect and/or measure physiological parameters from the subject, wherein the sensor comprises at least one optical emitter and at least one optical detector; and a processor coupled to the sensor and configured to receive and analyze signals produced by the sensor, and wherein the processor is configured to instruct the at least one optical emitter to emit a different wavelength of light during each of a series of respective time intervals such that a respective one of a plurality of different physiological parameters can be measured from the subject during each of the respective intervals via the at least one optical detector, wherein the processor is configured to: control the sensor to emit light at a first wavelength during a first time interval and to detect the light at the first wavelength according to a first polling rate; receive and analyze signals produced by the sensor during the first time interval to determine a heart rate of the subject; control the sensor to emit light at a second different wavelength during a second different time interval and to detect the light at the second wavelength according to a second different polling rate; and receive and analyze signals produced by the sensor during the second time interval to determine a blood pressure of the subject. control the sensor to emit light at a first wavelength during a first time interval and to detect the light at the first wavelength according to a first polling rate; receive and analyze signals produced by the sensor during the first time interval to determine a heart rate of the subject; control the sensor to emit light at a second different wavelength during a second different time interval and to detect the light at the second wavelength according to a second different polling rate; and receive and analyze signals produced by the sensor during the second time interval to determine a blood pressure of the subject. <EOS>