P4431Cardiopulmonary exerscise stress tests vs standard exercise stress tests in the rational prescription of physical activity in men

Abstract

Abstract Background The standard exercise stress test (ET) provides direct measurement of the load tolerated by the subject, but the cardiopulmonary exercise stress test (CPET) in addition to the measurement of the work load also provides direct measurement of the corresponding oxygen consumption. Objective The aim of the present study was to estimate the differences between the estimated oxygen consumption based on the load (ET) and the one directly measured with the CPET, and to highlight and quantify the inaccuracies of the indirect estimate of oxygen consumption and its consequences on the rational prescription of physical activity. Material and method The tests performed on 7544 males from January 2007 to October 2018 were analyzed. For each test the sustained load, the consumption of direct oxygen, and the estimated oxygen consumption based on the load sustained with the use of a formula provided by the American College of Sports Medicine and reported below: VO2max (ml/kg/min) = (10.51 x Watt) + (6.35 x weight in kg) − (10.49 x Età) + 519.3. The total population of the subjects examined was divided into two groups: Group A: 1358 subjects without signs of heart disease, and Group B: 6186 subjects with heart disease. Results In the total population the oxygen consumption (VO2) estimated on the basis of the load was overestimated in 22% of subjects, underestimated in 55% of subjects and overlapping in 23% of subjects. In Group B the calculated VO2 was overestimated in 38%, underestimated in 54% and overlapping in 8% of the subjects. In group A the calculated VO2 was overestimated in 33%, underestimated in 54% and overlapping in 9% of subjects. Conclusions In subjects with heart disease the VO2 calculated on the basis of the sustained load is overestimated or underestimated in 92% of subjects. The CPET through direct measurement of oxygen consumption provides a precise estimate of functional capacity, an essential prerequisite for a correct rational prescription of physical activity. Because of this peculiarity, the CPET is absolutely irreplaceable in cardiac patients in which a correct rational prescription of physical activity is crucial.