Mental exertion during an incremental exercise changes total oxidation in overweight adults
Poster Presentation
Paper ID : 2108-SSRC
Authors
1دانشگاه شهید بهشتی
2Department of Biological Sciences in Sport, Faculty of Sport Sciences and Health, Shahid Beheshti University, Tehran, Iran
3Control and Intelligent Processing Centre of Excellence, School of Electrical and Computer Engineering, College of Engineering, Tehran University, Tehran, Iran
Abstract
Introduction: The present study aimed to investigate the effect of mental exertion (ME) during incremental exercise on fat oxidation in overweight adults.
Methods: Seventeen overweight male and female adults (BMI >25 kg/m2) completed an incremental exercise test on a cycle ergometer two times, with and without ME. Energy expenditure (EE), maximum heart rate (HRmax), carbohydrate, fat oxidation, maximum fat oxidation (MFO), and maximal oxygen uptake (VO2max) were measured by indirect calorimetry, and the intensity of exercise that elicited MFO (Fatmax) was calculated. The Student's T-test and Repeated measure ANOVA were resorted to in the process of statistical analysis.
Results: ME significantly influenced EE and the carbohydrate oxidation rate (P < 0.05), but fat oxidation did not change. More specifically, ME reduced the carbohydrate oxidation rate at intensity levels of 50%, 60%, and 70%. Additionally, the EE rate with ME was lower than without ME during the incremental test at intensity levels of 40%, 50%, 60%, and 70% (P < 0.05). Moreover, MFO, HRmax, and VO2max were significantly lower in the ME (P < 0.05), but Fatmax did not change.
Conclusion: These results show that ME decreases the value of HRmax, VO2max, and MFO during the incremental exercise test, probably due to the increased workload with ME. Also, probably due to cognitive disorders and low brain capacity in overweight subjects, it has caused a reduction in EE and oxidation of carbohydrates. However, a trend toward systematic differences between the protocols reveals that further optimization of the incremental exercise protocol is needed to improve validity.
Methods: Seventeen overweight male and female adults (BMI >25 kg/m2) completed an incremental exercise test on a cycle ergometer two times, with and without ME. Energy expenditure (EE), maximum heart rate (HRmax), carbohydrate, fat oxidation, maximum fat oxidation (MFO), and maximal oxygen uptake (VO2max) were measured by indirect calorimetry, and the intensity of exercise that elicited MFO (Fatmax) was calculated. The Student's T-test and Repeated measure ANOVA were resorted to in the process of statistical analysis.
Results: ME significantly influenced EE and the carbohydrate oxidation rate (P < 0.05), but fat oxidation did not change. More specifically, ME reduced the carbohydrate oxidation rate at intensity levels of 50%, 60%, and 70%. Additionally, the EE rate with ME was lower than without ME during the incremental test at intensity levels of 40%, 50%, 60%, and 70% (P < 0.05). Moreover, MFO, HRmax, and VO2max were significantly lower in the ME (P < 0.05), but Fatmax did not change.
Conclusion: These results show that ME decreases the value of HRmax, VO2max, and MFO during the incremental exercise test, probably due to the increased workload with ME. Also, probably due to cognitive disorders and low brain capacity in overweight subjects, it has caused a reduction in EE and oxidation of carbohydrates. However, a trend toward systematic differences between the protocols reveals that further optimization of the incremental exercise protocol is needed to improve validity.
Keywords