Apparatus of calculating consumption of calory and method for operating the apparatus

A device for calculating calorie consumption and an operation method thereof are provided to precisely calculate the calorie consumption of a user performing exercise by determining an activity pattern of a user through an acceleration sensor attached to the user, and using a slope value according to the activity pattern and a heart rate measured through a heartbeat sensor attached to the user. A memory(150) stores an activity pattern table including activity pattern IDs and the slope value matched with each activity pattern ID. The acceleration sensor(110) is attached to the user and outputs an acceleration signal by detecting the movement of the user. An activity pattern determiner(130) determines the activity pattern of the user by reading the acceleration signal and extracts the slope value matched with the determined activity pattern from the activity pattern table. The heartbeat sensor(120) is attached to the user and measures the heart rate of the user. A data controller(140) calculates the calorie consumption of the user by using the extracted slope value and the measured heart rate.