Abstract: Method and calculations determine an individual's, or several individuals' simultaneous rates of oxygen consumption, maximum rates of oxygen consumption, heart rates, calorie expenditures, and METS (multiples of metabolic resting rate) in order to determine the amounts of work that is performed by the individual's body. A heart monitor measures the heart rate, and an accelerometer measures the acceleration of the body along one or more axes. An altimeter measures change in altitude, a glucose monitor measures glucose in tissue and blood, and thermometers, thermistors, or thermocouples measure body temperature. Data including body fat and blood pressure measurements are stored locally and transferred to a processor for calculation of the rate of physiological energy expenditure. Certain cardiovascular parameters are mathematically determined.