Patent ID: 8311769

Claim:
A portable monitoring device, adapted to couple to a body of a user, to calculate a number of stairs or flights of stairs traversed by the user, the portable monitoring device comprising: a housing having a physical size and shape that is adapted to couple to the body of the user; a motion sensor, disposed in the housing, to detect motion of the user and, in response thereto, to generate data which is representative of motion of the user; an altitude sensor, disposed in the housing, to sample an altitude of the user in response to a sample signal, wherein, in response to sampling the altitude of the user, the altitude sensor generates data which is representative of a change in altitude of the user; and processing circuitry, disposed in the housing and coupled to the motion sensor and the altitude sensor, to: generate the sample signal using the data which is representative of motion of the user, and determine a change in altitude of the user using the data which is representative of motion of the user and the data which is representative of a change in altitude of the user.