ABSTRACT Objective To evaluate the effect of an interdisciplinary intervention with a motivational approach on exercise capacity and usual physical activity levels in overweight and obese adolescents. Methods This is a randomized, controlled clinical trial with single blinding of subjects. Adolescents aged 15 to 18 years with overweight and obesity (body mass index ≥ 85 percentile) were included. The adolescents were randomized into two groups: interdisciplinary intervention or control − traditional approach aiming at lifestyle modifications. The initial evaluations were carried out, including the cardiopulmonary exercise test and the physical activity level measurement by using the International Physical Activity Questionnaire and a pedometer. The evaluations were performed in two moments: time zero (time of inclusion in the study) and after 3 months (end of intervention). There were 12 sessions with weekly meetings. Results A total of 37 participants were included, 19 in the Intervention Group. There were no significant differences in the baseline demographic, anthropometric and physical activity characteristics between groups, with mean age of 17.3±1.0 years in the Control Group, and 16.8±0.9 years in the Intervention Group (p=0.14). The motivational intervention did not cause significant differences (p>0.05) in the comparison of the variables of exercise capacity and usual physical activity (questionnaire and pedometer) between groups. Conclusion The intervention with a motivational approach did not alter exercise capacity and levels of usual physical activity in overweight and obese adolescents. Clinical Trial Registry: NCT02455973 and REBEC: RBR-234nb5.

ABSTRACT Objective To evaluate the effect of an interdisciplinary intervention with a motivational approach on exercise capacity and usual physical activity levels in overweight and obese adolescents. Methods This is a randomized, controlled clinical trial with single blinding of subjects. Adolescents aged 15 to 18 years with overweight and obesity (body mass index ≥ 85 percentile) were included. The adolescents were randomized into two groups: interdisciplinary intervention or control − traditional approach aiming at lifestyle modifications. The initial evaluations were carried out, including the cardiopulmonary exercise test and the physical activity level measurement by using the International Physical Activity Questionnaire and a pedometer. The evaluations were performed in two moments: time zero (time of inclusion in the study) and after 3 months (end of intervention). There were 12 sessions with weekly meetings. Results A total of 37 participants were included, 19 in the Intervention Group. There were no significant differences in the baseline demographic, anthropometric and physical activity characteristics between groups, with mean age of 17.3±1.0 years in the Control Group, and 16.8±0.9 years in the Intervention Group (p=0.14). The motivational intervention did not cause significant differences (p>0.05) in the comparison of the variables of exercise capacity and usual physical activity (questionnaire and pedometer) between groups. Conclusion The intervention with a motivational approach did not alter exercise capacity and levels of usual physical activity in overweight and obese adolescents. Clinical Trial Registry: NCT02455973 and REBEC: RBR-234nb5.

ABSTRACT Objective: To compare the values of measured maximum heart rate (HRmax) and maximum heart rate estimated by different equations during the cardiopulmonary exercise test (CPET) in obese adolescents. Methods: This is a cross-sectional study. Adolescents aged between 15 and 18 years old, with obesity (BMI Z-score>2.0) were included. Demographic and anthropometric data were collected, followed by CPET, recording HRmax. The highest heart rate reached at peak exercise was considered as HRmax. The comparison between measured and estimated HRmax values was performed using four previous equations. Descriptive statistics and the ANOVA test (Bonferroni post-test) were used. Results: Fifty-nine obese adolescents were included, 44% of them male. The mean age was 16.8±1.2 years old and the BMI (Z-score) was 3.0±0.7. At peak exercise, the mean HRmax (bpm) was 190.0±9.2, the respiratory coefficient was 1.2±0.1, and the VO2max (mL/kg/min) was 26.9±4.5. When comparing the measured values of HRmax with those estimated by the different formulas, the equations “220-age”, “208-0.7 x age” and “207-0.7 x age” were shown to overestimate (p<0.001) the measured HRmax results in obese adolescents. Only the “200-0.48 x age” equation presented similar results (p=0.103) with the values measured in the CPET. Conclusions: The findings of the present study demonstrate that the equation “200-0.48 x age” seems to be more adequate to estimate HRmax in obese adolescents.

ABSTRACT Objective: To compare the values of measured maximum heart rate (HRmax) and maximum heart rate estimated by different equations during the cardiopulmonary exercise test (CPET) in obese adolescents. Methods: This is a cross-sectional study. Adolescents aged between 15 and 18 years old, with obesity (BMI Z-score>2.0) were included. Demographic and anthropometric data were collected, followed by CPET, recording HRmax. The highest heart rate reached at peak exercise was considered as HRmax. The comparison between measured and estimated HRmax values was performed using four previous equations. Descriptive statistics and the ANOVA test (Bonferroni post-test) were used. Results: Fifty-nine obese adolescents were included, 44% of them male. The mean age was 16.8±1.2 years old and the BMI (Z-score) was 3.0±0.7. At peak exercise, the mean HRmax (bpm) was 190.0±9.2, the respiratory coefficient was 1.2±0.1, and the VO2max (mL/kg/min) was 26.9±4.5. When comparing the measured values of HRmax with those estimated by the different formulas, the equations “220-age”, “208-0.7 x age” and “207-0.7 x age” were shown to overestimate (p<0.001) the measured HRmax results in obese adolescents. Only the “200-0.48 x age” equation presented similar results (p=0.103) with the values measured in the CPET. Conclusions: The findings of the present study demonstrate that the equation “200-0.48 x age” seems to be more adequate to estimate HRmax in obese adolescents.