A method for quantifying activity levels of an individual within apredetermined time period including measuring a plurality of activityvariables from an individual during a predetermined time period, providing aplurality of activity variables with minimum and maximum threshold values anda weighing factor, calculating a subindex for each of the activity variablesas a function of the minimum and maximum threshold values and the weighingfactor, and calculating a sum of the activity variables to determine anactivity index of an individual. A personal activity level analysis system isconfigured to execute the method for obtaining an activity index used inquantifying an activity level of an individual.