André O Werneck
1* 
, Marcelo Romanzini
2, Danilo R. Silva
3, Adewale L. Oyeyemi
4, Maria R. Bueno
2, Enio R. V. Ronque
21 Department of Nutrition, School of Public Health, Universidade de São Paulo (USP), São Paulo; Brazil
2 Physical Activity and Health Laboratory, Department of Physical Education, Universidade Estadual de Londrina, Londrina, Brazil
3 Departament of Physical Education, Universidade Federal de Sergipe - UFS, São Cristóvão, Brazil
4 Department of Physiotherapy, College of Medical Sciences, University of Maiduguri, Borno State, Nigeria
Abstract
Background: Our aim was to analyze the association of self-reported mentally-passive and
mentally-active sedentary behaviors with different patterns (bouts and breaks) of device-measured sedentary time in adolescents.
Methods: This was a cross-sectional study conducted among 375 adolescents (177 boys) aged 1015 years. Total time, bouts and breaks of sedentary time were measured through accelerometers. Self-reported sedentary behavior in different activities was summed and divided into mentally-active (playing electronic games, studying and reading) and mentally-passive (watching TV, watching DVD, and using computer for leisure). Bayesian linear regression models were used for association analyses.
Results: Only mentally-passive sedentary behaviors were positively associated with longer bouts
[1-4 minutes: mean posterior distribution: -0.431 (95% credible interval: -0.745 to -0.114); =15 minutes: 0.641 (0.122 to 1.222)] and lower number of breaks [-0.138 (-0.228 to -0.044)] of device-measured sedentary time.
Conclusion: Self-reported mentally-passive sedentary behaviors are associated with longer
bouts and lower breaks of device-measured sedentary time.