The present inventions, in one aspect, are directed to a portable activity monitoring device comprising a housing having a physical size and shape that is adapted to couple to the user's body, a plurality of sensors (for example, motion sensor and altitude sensor) disposed in the housing. The monitoring device may further include processing circuitry, disposed in the housing and electrically coupled to the plurality of sensor, to calculate the activity points corresponding to the physical activity of the user using the sensor data, wherein the activity points correlate to an amount and intensity of the physical activity of the user, and output the data which is representative of the activity points. The monitoring device may also include a display, coupled to the processing circuitry, may output the data which is representative of the activity points to the user.