Sex and Gender-based Analysis of this topic
Definition
Television viewing, computer use, reading, occupational sitting, and motorized transportation are classified by many research experts as sedentary behaviours. In recent years, this concept has evolved as distinct from “lack of physical activity” due to the significant health impacts independently associated with sedentary behaviour, including weight gain, type 2 diabetes mellitus, some cancers, abnormal glucose metabolism, metabolic syndrome, and cardiovascular disease [1]. Some claim these sedentary behaviours also induce psychological problems such as depression [2], lower self-esteem, decreased academic performance [2], and reduced bone mineral density [3]. Strategies to reduce sedentary behaviour amongst men and women are needed in order to reduce the risk of associate chronic health conditions. Although the definitions are not consistent in the literature, in Canada, sedentary behaviours have been defined as “a distinct class of behaviours characterized by little physical movement and low energy expenditure (=1.5 METs)”[3].
Sex Issues
Sedentary behaviour has been associated with different health effects for men and women. There is a suggestion that for men, sedentary behaviour is associated with an increased risk of colon cancer, while for women there may be increased risk for endometrial and ovarian cancer [3]. With respect to overweight, a study looking at both sedentary behaviour and physical activity and the association with overweight showed that both sedentary behaviour and physical inactivity were associated with being overweight among boys. However, sedentary behaviour played a larger role than physical activity in predicting overweight among girls [4].
Gender Issues
It is estimated that Canadian men and women spend approximately equal hours per day in sedentary behaviour [5] with minor exceptions. More men than women report being frequent users of television and computers, while women are more likely to report frequent sitting and reading. According to the Canadian Community Health Survey (2007), 24% of women and 27% of men spend 15 or more hours per week watching television, 14% of women and 18% of men spend 11 or more hours per week on leisure-time computer use, while 15% of women and 9% of men report being frequent readers) [6]. Women also tend to spend more time on household chores, shopping, and caregiving than men [6], activities that are often associated with physical movements. However, women engage in activities other than television viewing and computer use which could be linked to sedentary behaviour (e.g., personal care and social interactions) [4] but which are not often captured in research studies [4]. Communication-based sedentary behaviour is also common and it has been estimated that 58% of girls (grades 5 to 8) spend more than 2 hours per day talking on the phone, texting, or instant messaging [8].
Diversity
Differences in sedentary behaviour rates exist in terms of sex, age, marital status, education, immigrant status, and education but the differences are often in opposite directions when comparing computer use and television viewing. Frequent leisure-time computer users are often younger, have not been married, are more likely to have a postsecondary education, and live in urban areas. Unemployment has also been associated with high leisure-time computer use [6]. Frequent television viewers, on the other hand, are more likely to have less than secondary graduation, be in the lowest household income quintile, and be living in rural areas. Frequent television viewing also rose steadily with age. Similarly to computer use, television viewing is more common among never married than those that are married. Further, recent immigrants are more likely to report frequent computer use than people that are Canadian-born, but less likely to report watching television [6]. Provincial and territorial differences have also been noted for television viewing and computer use with more frequent television viewers in Nunavut (40%), New Brunswick (32%), and Quebec (31%) than the national average (29%) and more frequent leisure-time computer users in Nunavut (20%), British Columbia (18%), and Ontario (16%) than the national average (15%) [6].
Equity
Inequities can influence time spent in sedentary pursuits, including inequities related to power, gender, and income. Neighbourhood safety is an important factor for sedentary behaviour and children’s television time has been linked to mothers’ perceptions of neighbourhood safety where children in the least safe neighbourhoods tend to spend more time watching TV [9]. It is possible that girls and women may have less power and entitlement to move with safety in their neighbourhoods and may therefore spend more time sedentary. Women may also be more likely to have jobs with limited ability to change the structure of their workplace and, as a result, have fewer opportunities to reduce the amount of time spent sitting.
Critique
The relationships between sedentary behaviour and morbidity and mortality have not received as much research and policy attention as the relationship between physical activity, morbidity, and mortality. Most studies to date include only a limited selection of sedentary behaviours, such as watching television and computer games; involvement in these activities may vary by sex, income, and neighbourhood. Measuring sedentary behaviour is a challenge as these behaviours are often engaged in sporadically throughout the day and may be harder to recall than scheduled physical activities. Self-reports, a common measure of both physical activity and sedentary behaviour, may therefore not be a reliable measure of sedentary behaviour [3,6]. Further research using tools such as accelerometers or inclinometers is needed.