IJCS | Volume 32, Nº4, July/August 2019

366 1. Bruce AR, Kusumi F, Hosmer, D. Fundamentals of clinical cardiology. Am Heart J. 1973;85(4):546-62. 2. Carreira MA. Fisiologia do Exercício. In: Ergometria: ergoespirometria, cintilografia e ecocardiografia de esforço. Costa RV & Carreira MA. Ed. Rio de Janeiro: Atheneu;2007. 3. Meneghelo RS, Araujo CG, Stein R, Mastrocolla LE, Albuquerque PF, Serra SM, et al. Sociedade Brasileira de Cardiologia. III Diretrizes da Sociedade Brasileira de Cardiologia sobre Teste Ergométrico. Arq Bras Cardiol. 2010;95(5 Suppl 1):1-26 4. Ong KC, Loo CM, Ong YY, Chan SP, Earnest A, Saw SM. Predictive values for cardiopulmonary exercise testing in sedentary Chinese adults. Respirology. 2002;7(3):225-31. 5. Froelicher VF ; Myers JN. Exercise and the heart. Philadelphia: Saunders;2000. 6. Rodrigues AN, Peres AJ, Carletti L, Bissoli NS, Abreu GR. Maximum oxygen uptake in adolescents as measured by cardiopulmonary exercise testing: a classification proposal . J Pediatr (Rio J). 2006;82(6):426-30. 7. Wei M, Kampert JB, BarlowCE, NicamanMZ, Gibbons LW, Paffenbarger RS, et al. Relationship between low cardiorespiratory fitness and mortality in normal-weigth, overweigth and obese men. JAMA. 1999;282(16):1547-53 8. Myers J, PrakashM, Froelicher V, Do D, Partington S, Atwood E. Exercise capacity and mortality among men referred for execise testing. N Engl J Med. 2002;346(11):793-801 References developed in a North American population in the 70’s. When applied to the Brazilian population, the formula was found to overestimate VO 2 max values. According to Neder et al., 18 this difference is common in studies using prediction equations for VO 2 max. We have recently published reference values for CPET in our population, 23 and a direct and unequivocal measurement of VO 2 gives us the chance to evaluate actual cardiorespiratory fitness of each individual by sex and age range. The fact that the tests were performed on different days, using different protocols (Bruce versus ramp) may have been a limitation of this study. However, the hemodynamic parameters obtained from the tests were not significantly different, allowing us to infer that there was a similar cardiorespiratory and physical performance by the subjects in both tests. In the present study, we found a significant discrepancy in the classification of cardiorespiratory fitness by the AHA and by the VO 2 prediction formulas. The BP is more widely used for VO 2 calculation in clinical practice in Brazil than spiroergometric tests. Therefore, a possible overestimation of VO 2 values by the BP results in an erroneous evaluation of the cardiorespiratory fitness of the individuals. This, in turn, may represent a lack of opportunity to advise young individuals about the negative effects of a sedentary lifestyle and a low cardiorespiratory capacity. Conclusion The assessment of aerobic capacity is an important risk stratification tool in young, physically inactive subjects. Prediction formulas of VO 2 max, derived from cycle or treadmill exercise tests using the BP, are not able to reproduce the true cardiorespiratory capacity in this population, overestimating it. The present study draws attention to the need for an accurate measurement of fitness in this group by CPET, aiming at enabling early warning of these individuals about the risks of a sedentary lifestyle. Author contributions Conception and design of the research: Rocha Neto AM, Herdy AH. Acquisition of data: Rocha Neto AM, Herdy AH, Souza P. Analysis and interpretation of the data: Rocha Neto AM, Herdy AH, Souza P. Statistical analysis: Rocha Neto AM, Herdy AH, Souza P. Obtaining financing: Rocha Neto AM. Writing of the manuscript: Rocha Neto AM, Souza P. Critical revision of the manuscript for intellectual content: Rocha Neto AM, Souza P. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding There were no external funding sources for this study. Study Association This study is not associated with any thesis or dissertation work. Ethics approval and consent to participate This article does not contain any studies with human participants or animals performed by any of the authors. Herdy & Souza Comparison of direct and estimatedVO 2 Int J Cardiovasc Sci. 2019;32(4):362-367 Original Article