Validity of the modified shuttle walk test to assess cardiorespiratory fitness after exercise intervention in overweight/obese adults with primary hypertension

The study aimed to assess whether the Modified Shuttle Walk Test (MSWT) can detect changes in cardiorespiratory fitness (CRF) in overweight/obese people with hypertension (HTN) after an exercise intervention evaluating the equation presented in the previous research by Jurio-Iriarte et al. Participants (N= 248) performed a peak cardiorespiratory exercise test (CPET) and MSWT before and after 16-weeks of different types of aerobic exercise intervention. The formula of Jurio-Iriarte et al. was used to predict peak oxygen uptake (V?O_2peak). The correlation between measured and predicted V?O_2peak was strong (r= 0.76, P< 0.001) with a standard error of estimate (SEE) of 4.9 mL·kg^?1·min^?1; SEE%= 17%. The intraclass correlation coefficient indicates a moderate level of association and agreement (ICC= 0.69; 95% CI 0.34–0.82; P< 0.001) between the measured and predicted V?O_2peak. When analyzing obese participants alone (N= 128), MSWT equation was more accurate compared to the whole sample (ICC= 0.76; 95% CI 0.52–0.87). The relationship between the change of measured and predicted V?O_2peak at follow-up was weak (r= 0.42, P< 0.001) with a 31% SEE, and a low level of association and agreement (ICC= 0.31; 95% CI 0.06–0.49; P< 0.001). In conclusion, although MSWT does not accurately predict CRF in people with HTN after exercise intervention and questions its validity, the new equation may have practical application to estimate V?O_2peak for obese people with HTN when CPET is not available.

Abbreviations: AC: Attention Control; BM: Body Mass; BP: Blood Pressure; CI: Confidence Interval; CRF: Cardiorespiratory Fitness; CPET: Cardiopulmonary Exercise Test; HTN: Primary Hypertension; HR: Heart Rate; HV-HIIT: High-Volume and High-Intensity Interval Training; ICC: Intraclass Correlation Coefficient; LV-HIIT: Low-Volume and High-Intensity Interval Training; MICT: Moderate-intensity continuous training; MSWT: Modified Shuttle Walk Test; SD: Standard Deviation; SEE: Standard Error of Estimate; V?O_2peak: Peak Oxygen Uptake.