IJCS | Volume 32, Nº4, July/August 2019

336 Continuation Table 3 9 Running slowly at least 1 km or 10 minutes (no walking or stopping) Attending spinning or step aerobics classes (low or moderate intensity) Engaging in martial arts for at least one hour with short breaks only 5 9 to 11.9 10 Running continuously for 10 to 15 minutes Running for at least one minute at 10 km/h (167 m/min) outdoors or 10.5 km/h on the treadmill Pedaling outdoors or on the road at 20 and 25 km/h for up to half an hour 11 Running at least one minute at 11 km/h (184 m/min) outdoors or 11.6 km/h on the treadmill Attending fast-pedaling spinning or running classes 12 Running continuously for up to 40 minutes Running for at least one minute at 12 km/h (200 m/min) outdoors or 12.7 km/h on the treadmill Playing ball sports at very intense pace and for at least 30 minutes without breaks 6 12 to 14.9 13 Running for at least one minute at 13 km/h (200 m/min) outdoors or 13.8 km/h on the treadmill Running 10 km in about 1 hour Pedaling outdoors or on the road at 20 and 25 km/h for more than one hour 14 Running for at least one minute at 14 km/h (233 m/min) outdoors or 14.9 km/h on the treadmill Running 10 km in 53 to 57 minutes or completing a half-marathon in about 2h15min 15 Running a half-marathon in about 2 hours or a marathon in about 4 ½ hours Running for at least one minute at 15 km/h (250 m/min) outdoors or 16 km/h on the treadmill 7 15 to 17.9 16 Running for at least one minute at 16 km/h (266 m/min) outdoors or 17.2 km/h on the treadmill Running a half-marathon in about 1h50min to 1h55min or a marathon in 4h to 4h15min 17 Running for at least one minute at 17 km/h (283 m/min) outdoors or 18.4 km/h on the treadmill Running a half-marathon in about 1h40min or a marathon in 3h40min to 4h 18 Running a half-marathon in 1h30min to 1h40min or a marathon in 3h15min to 3h40min Running for at least one minute at 18 km/h (300 m/min) outdoors or 19.6 km/h on the treadmill 8 18 to 19.9 20 Running a half-marathon in 1h20min to 1h30min or a marathon in 3h to 3h15min Running for at least one minute at 20 km/h (333 m/min) outdoors or 22 km/h on the treadmill 9 20 > 20 Running a half-marathon in less than 1h20min or a marathon in less than 3 hours 10 > 20 * slope: 1% means climbing 1 meter for every 100 meters walked on flat Araújo et al. CLINIMEX aerobic fitness questionnaire Int J Cardiovasc Sci. 2019;32(4):331-342 Original Article METs - and measured aerobic fitness - 8.56 ± 0.12 METs - (p < 0.001), with standard error of the mean differences of only 0.05 METs. The median of the difference between estimated and measured aerobic fitness was only 0.2 METs with interquartile range from -0.7 to 1.3 METs (see violin plot in Figure 1). Table 4 describes separately men and women’s data for some of these results. A very direct and strong association was found between estimated (C-AFQ) and measured (CPET) VO 2 max values — r = 0.91 (p < 0.001). Linear regression analysis found a coefficient of determination or r 2 value of 0.833 (p < 0.001) and a standard error of estimate of 1.54 METs. The scatterplot of 1,000 subject’s data, identity line and 2-MET individual difference lines are presented in Figure 2. Considering that four different physicians have applied the C-AFQ for the 1,000 subjects, we analyzed estimated and measured aerobic fitness values and their respective differences for each one of them in order to search for any applicant C-AFQ bias. Median and interquartile measured METs were: physicians 1–8.7 [6.1–11.1], physician 2–6.8 [5.0–9.3], physician 3–7.9 [5.7–11.8] and physician 4–7.7 [4.9–13.7] (p < 0.001). Despite these quite distinct levels of aerobic fitness in the subjects evaluated by the four physicians, C-AFQ values were quite similar among them (p = 0.055) and multiple comparison analysis identified that the only the physician’s pair 1–2 significantly differed (Figures 3 and 4) —exactly the two physicians that were in the extremes of median values for measured aerobic fitness.