KeywordsWaist Circumference Mental Health Problem Physical Exercise Sedentary Behavior Physical Activity Level
Sedentary behaviors are an increasingly common problem worldwide, with important health consequences. These behaviors include long durations of sitting in front of the TV or the computer, playing computer or TV games, and a general lack of peripheral limb movements. These behaviors have risen due to a multitude of reasons including technological advancements, greater dependence on transportation, urbanization and hence smaller distances to work or schools spent walking, the omnipresence of TV and computers, and our dependence on such means for information, work, leisure, and communication. Various measures and scales exist to assess sedentary behaviors, and these depend on the type of behaviors assessed, the time frame the questions refer to (days, weeks, etc.), and the response format (e.g., a Likert scale or hours). This variability in assessment and use of different cutoffs could of course impact on the prevalence of sedentary behaviors identified in various samples. The prevalence of sedentary behaviors was found to be 58 % in a nationally representative sample of Americans aged between 20 and 59 years. When looking just at sitting, one in four Americans spends 70 % of their waking time sitting. Furthermore, people in developed countries may spend 4 h a day watching TV and 1 h a day in their vehicle. Importantly, the metabolic and health consequences of sedentary behaviors are distinct from the effects of lack of physical exercise (Owen et al. 2010). In a 21-year follow-up study, the number of hours riding in a car, alone or in combination with hours in front of a TV, significantly predicted cardiovascular disease mortality, independent of confounders (Warren et al. 2010). In contrast, taking daily breaks from sedentary behaviors is related to reduced waist circumference and to improved metabolic outcomes, independent of total amount of sedentary behaviors and of physical exercise (Healy et al. 2008). Mental health problems such as anxiety and depression are also associated with more sedentary behaviors, independent of general physical activity level (de Wit et al. 2011). Finally, an important study examined prospectively over 25 years the relationship between sedentary behavior (TV viewing >3 h/day) and long-term cognitive functions using various measures of processing speed and executive functioning. Indeed, sedentary behavior significantly predicted longer processing speed and poorer executing functioning (inhibition), independent of multiple confounders such as education, age, sex, and hypertension (Hoang et al. 2016). Thus, sedentary behaviors are an important topic for research and intervention in behavior medicine.
References and Further Readings
- Hoang, T. D., Reis, J., Zhu, N., Jacobs, D. R., Jr., Launer, L. J., Whitmer, R. A., Sidney, S., & Yaffe, K. (2016). Effect of early adult patterns of physical activity and television viewing on midlife cognitive function. Journal of the American Medical Association – Psychiatry, 73, 73–79.PubMedGoogle Scholar