Summary: One metabolic equivalent (MET) is definedas the amount of oxygen consumed while sitting at rest and is equal to 3.5 ml O2 per kg body weightx min. The MET concept represents a simple, practical, and easily understood procedure for expressing the energy cost of physical activities as a multiple of the resting metabolic rate. The energy cost of an activity can be determined by dividing the relative oxygen cost of the activity (ml O,/kg/min) x by 3.5. This article summarizes and presents energy expenditure values for numerous household and recreational activities in both METS and watts units. Also, the intensity levels (in METS) for selected exercise protocols are compared stage by stage. In spite of its limitations, the MET concept provides a convenient method to describe the functional capacity or exercise tolerance of an individual as determined from progressive exercise testing and to define a repertoire of physical activities in which a person may participate safely, without exceeding a prescribed intensity level.Key words: metabolic equivalents, energy cost, oxygen consumption, exercise prescription, functional capacity cost of activities. METS are also routinely utilized to describe the functional capacity or aerobic power of an individual and to provide a repertoire of activities in which he or she can safely participate. Since the term METS appears frequently in the North American literature and since some persons may not be completely familiar with the concept, a definition of the term and its utilization could prove useful. Our purpose, therefore, is to ( I ) define the concept of METS, (2) compare METS and watts of selected household and recreational activities, and (3) describe the use of METS in the formulation of an exercise prescription. DefinitionA MET is defined as the resting metabolic rate, that is, the amount of oxygen consumed at rest, sitting quietly in a chair, approximately 3.5 ml 02/kg/min (1.2 kcallmin for a 70-kg person).* As such, work at 2 METS requires twice the resting metabolism or 7.0 ml O,/kg/min and three METS requires three times the resting metabolism (10.5 ml 02/kg/min), and so on.

It was concluded that in the present study, exercise training had little or no effect on hemodynamic measurements and that the training effects achieved in patients with left ventricular dysfunction are most likely due to corrected impaired vasodilation, not necessarily to cardiac function. The importance of using a control group in this type of study and the wide interindividual variations in training responses are emphasized.

Treatment with 40 mg simvastatin day-1 reduces serum cholesterol and slows the progression of coronary artery disease significantly within a short period of treatment time. In the treatment group, retardation of progression is inversely correlated to the LDL-cholesterol levels achieved.

The effect of acetoacetate infusion on myocardial metabolism was studied in 13 dogs at varying concentrations of acetoacetate. Acetoacetate was extracted by the myocardium at arterial levels of from 1 to 54 mg/100 ml. At arterial levels of above 60 mg/100 ml, extraction of acetoacetate by the heart was very small. Considerable amounts of the infused acetoacetate were reduced to beta-hydroxybutyrate. Acetoacetate inhibited the utilization of free fatty acids by the heart, resulting in a rise in the respiratory quotient of the heart. An increase in the myocardial extraction of lactate occurred at arterial acetoacetate levels of below 34 mg/100 ml. Between 34 and 80 mg/100 ml of acetoacetate levels, myocardial lactate extraction declined; the ketone became the preferred fuel of the myocardium at arterial acetoacetate levels between 34 and 54 mg/100 ml. Arterial glucose levels fell gradually during the experiment, leading to severe hypoglycemia. The negative myocardial balance of pyruvate significantly increased throughout the experiment. Coronary blood flow, heart rate, left ventricular pressure, myocardial contractility, and EKG were not affected significantly by arterial acetoacetate levels ranging from 1 to 80 mg/100 ml.