Six Minute Step Test Vs. Six Minute Walk Test to Measure VO2 Peak in Obese Class 1 Adults: An Observational Study

Abstract

Introduction: Exercise testing and interpretation is important for determining exercise capacity and identifying factors which might limit the exercise performance. Impaired cardiorespiratory fitness and sedentary lifestyle are hallmarks of obesity and thus assessing the VO2 peak in such a population is important. While both the SMST and 6MWT are commonly used functional tests, limited research directly compares their effectiveness in Class 1 obese adults. Addressing this gap in the literature can provide valuable insights into the strengths and limitations of each test, guiding researchers and clinicians in selecting the most appropriate assessment tool for this specific population. Identifying the test that poses lower risks and discomfort for obese individuals is essential to ensure their safety during exercise testing. This observational study aimed to compare the Six Minute Step Test (6MST) and the Six Minute Walk Test (6MWT) in measuring VO2 peak in obese Class 1 adults. Method: This Observational study, with convenient sampling and sample size 66, included adults between age 18- 25 within the category of Obese Class 1 (BMI 30-34.9 kg/m2). The exclusion criteria was any Cardio-vascular and respiratory conditions, recent fractures or diagnosed case of any neurological condition. The participants performed both the 6 Minute Walk Test and 6 Minute Step Test in random order and the heart rate and SpO2 were recorded pre and post-test, and VO2 peak was calculated by the indirect method. Result: Results were calculated using paired t-test and significant statistical difference was found between the 6 Minute Walk test and 6 Minute Step Test. Specifically, both VO2 peak and heart rate were significantly different between the tests, with 6MST yielding higher values. Conclusion: Consequently, this study suggests that 6MST cannot substitute for 6MWT in assessing aerobic capacity in Class 1 obese adults. The implications of these findings underscore the importance of considering specific physiological demands and practical constraints when selecting assessment tools for this population. Key words: 6 Minute Walk Test, 6 Minute Step Test, Obesity, VO2 Peak, Obese Class 1, Cardiorespiratory fitness.