ABSTRACT
Cardiorespiratory fitness is most accurately determined directly by a maximal exercise test in which oxygen uptake is determined directly. There are many components of fitness that are important to health, including cardiorespiratory fitness, muscular strength, endurance, and body composition. The Centers for Disease Control and Prevention and the American College of Sports Medicine define physical fitness as “a set of physical attributes that people have or achieve that relates to the ability to perform physical activity”. An indirect method for estimating the fitness level of an individual is based on the same principle as that for the direct assessment of VO2 max with one exception: oxygen consumption is not directly measured. A number of walking tests have also been developed for estimating cardiorespiratory fitness or assessing the functional status of patients with cardiovascular or pulmonary disease in clinical settings. Cardiorespiratory fitness can also be estimated indirectly from the external work rate achieved on a treadmill or cycle ergometer.
