Publication
Sedentary behaviour among Scottish youth: prevalence and determinants
| Contents: | Acknowledgement Summary Introduction 2. Measurement of sedentary behaviour in youth 3. What is the prevalence of sedentary behaviour in Scottish youth? 5. References |
3. What is the prevalence of sedentary behaviour in Scottish youth?
Results for this report will address the prevalence of key sedentary behaviours and physically active pursuits, as well as descriptive summary data on these behaviours. To keep the volume of data manageable, variables were conceptualised as follows:
- sedentary behaviours: TV/video viewing, playing computer/video games, using the computer (excluding computer-based homework and games), using motorised transport.
- physically active behaviours: active transport, sports and exercise.
Results are reported for boys during the school week (Table 3.1) and at weekends (Table 3.2), and for girls during the school week (Table 3.3) and at weekends (Table 3.4). Each table shows results by school year and for the whole of the sub sample.
Please note tables 3.1, 3.2, 3.3, and 3.4 are not available on-line. Please contact the
3.1 TV/Video viewing
3.1.1 BoysResults in Table 3.1 show that half (48%) of boys watched up to 2 hours of TV per weekday with only a small minority (8%) exceeding 4 hour.day -1. Two hours or less is considered acceptable by the American Academy of Paediatrics (1986). Overall, boys averaged 2 hours and 7 minutes of TV viewing per weekday. Trends showed boys in Year S4 to be less likely to watch more than 2 hour.day -1 during the week (39%) than those in Years S3 (58.5%) and S2 (49%). Mean scores reflected this trend: Year S2=130 min.day -1; S3=135 min.day -1; S4=109 min.day -1.
Prevalence estimates increased at weekends (Table 3.2) with only 19% watching 2 hours or less per day and nearly one-third (31%) exceeding 4 hours. Average daily weekend viewing time is 3 hours and 15 minutes. Trends showed boys in Year S4 are less likely to watch more than 4 hour.day -1 during the weekend (24%) than those in Years S3 (33%) and S2 (33%). Mean scores reflected this with a decline from Years S2 (207 min.day -1) and S3 (190 min.day -1) to S4 (177 min.day -1).
Results in Table 3.3 show that 59% of girls watched up to 2 hours of TV per weekday with only a small minority (4%) exceeding 4 hour.day -1. Overall, girls averaged 1 hour and 49 minutes of TV viewing per weekday – 18 min s less than boys. Girls in Year S4 were less likely to watch more than 2 hour.day -1 during the week (28%) than those in Years S3 (41.5%) and S2 (45%). Mean scores reflected this with a decline in TV viewing from Year S2 (116 min.day -1) to S3 (109 min.day -1) and to S4 (98 min.day -1).
Prevalence estimates increased at weekends (Table 3.4) with 30% watching 2 hours or less per day and a quarter (24%) exceeding 4 hours. Average daily weekend viewing time was 2 hours and 39 minutes – 36 mins. less than boys. Trends showed girls in Year S4 to be less likely to watch more than 4 hour.day -1 during the weekend (17%) than those in Years S3 (29%) and S2 (26%). Mean scores reflected this with fewer minutes of TV viewing at weekends for those girls in S4 (131 min.day -1) compared with their younger counterparts (S2=170 min.day -1; S3=171 min.day -1).
For TV viewing data, we conclude that:
- many boys and girls have ‘acceptable’ viewing levels during the week
- unsurprisingly, weekends provide opportunity for large amounts of TV viewing, with a significant minority watching more than 4 hour.day -1
- TV viewing is greater for boys and younger participants.
3.2 Other prevalent sedentary behaviours
TV viewing is the most prevalent leisure-time sedentary behaviour for young people. However, there are many other opportunities to be sedentary, including the use of new technologies. During the week, boys averaged 31 min.day -1 playing computer games (60 minutes at weekends) and a further 11.5 min.day -1 using the computer for other purposes. This contrasted with girls who averaged 3 minutes (7 at weekends) and 13 minutes respectively. However, many boys (43%) reported no computer game playing on weekdays and less than a quarter (20%) reported playing more than one hour per day. Boys showed minimal age trends. Other computer use was quite low with 71% of boys and 67% of girls reporting no use at all during the week. It should be noted, however, that this does not include computer-based homework.
Girls reported spending an average of 32 min.day -1 in motorised transport during the week, and 51 min.day -1 at weekends. Boys reported similar use during the week (28 min.day -1) but less at weekends (36 min.day -1) compared to girls. Only 25.5% of boys and 17% of girls spent no time in motorised transport during the week, whereas more than one-third of boys (39%) and girls (35%) spent between 30 and 60 minutes daily, with some boys (12%) and girls (15%) spending more than 1 hour in motorised transport.
Homework was also a prevalent sedentary behaviour, with boys averaging 29 min.day -1 during the week, and girls 39 min.day -1. At weekends, this gender difference was maintained with boys taking 14 and girls 26 min.day -1.
From the data on other prevalent sedentary behaviours, we conclude that:
- boys are significantly more attracted to playing computer games than girls, although a large minority of boys play no computer games during the week
- computer use, excluding use of computers in homework, is quite low
- use of motorised transport is quite high.
3.3 Physically active pursuits
During the week, boys (44 min.day -1) were markedly more active than girls (21.5 min.day -1) in sports and exercise, although these figures excluded school physical education. However, 38% of boys and 55% of girls reported no sports and exercise at all during the week, figures rising to 48% and 72% at weekends, respectively. The least active in sports and exercise were Year S3 girls, averaging only 17.5 min.day -1 during the week and 30 min.day -1 at weekends. No sport and exercise was reported by 57% of girls in Year S3 during the week and by 79% of girls in S4 at weekends.
Time in active transport, such as walking to school, averaged 26 min.day -1 during the week for boys and 30 min.day -1 for girls. These dropped to 14.5 and 19 min.day -1 respectively at weekends. Nearly one-quarter of boys (22%) took no active transport during the week, but this was much less in girls (13%).
For sports and exercise and active transport during the week in combination, boys averaged 70 min.day -1 of physical activity, meeting the national recommendation of one hour per day of moderate intensity physical activity on most days of the week (Biddle, Sallis, & Cavill, 1998). Girls averaged 51.5 min.day -1 in these two activities, with Year S3 being the least active with 46 min.day -1. Many boys, however, did meet the recommended 60-minute target. This was achieved by 48% during the week and 50% at weekends. But only 31% of girls achieved 60 minutes during the week and only 26% on the weekend.
From the data on physically active behaviours, we conclude that:
- boys are significantly more active than girls, confirming prior research
- there is still a sizeable minority of boys, and a majority of girls, choosing no sports and exercise
- active transport data give some signs for optimism, but coupled with the data on motorised transport, there is room for a shift to more active forms of transport
- average physical activity levels of boys, but not girls, appear to meet national recommendations.
3.4 Analyses by ethnicity
White-European ethnicity comprised 98% of the sample. Other ethnic groups are shown in Table 2.2. Conclusions concerning ethnic differences in sedentary and physically active behaviours are therefore not possible due to small sample sizes. However, the small group of young people of Asian ethnicity, in comparison to those reporting themselves to be White-European, showed, for weekday data, higher rates of TV viewing and use of active transport, but markedly less involvement in sports and exercise (4 min.day -1 vs. 30 3).
3 Cohen’s d effect size = 0.89, described as ‘large’
3.5 Analyses by socio-economic status
Using deprivation categories based on participant’s postcodes, and created from the Medical Research Council’s data base4, we found no significant relationship between deprivation category score (1=more affluent; 7=more deprived) and the behaviours of TV viewing, active transport, or sports and exercise, for either boys or girls.
In addition, two groups were created (scores 1-3 = ‘affluent group’; 5-7 = ‘deprived group’; those with a mid-range score of 4 were excluded) to test for differences across behaviours. For males, there were no differences in TV viewing, playing computer games, active transport, or sports and exercise. However, those in the more affluent group reported greater time spent on the computer than those in the more deprived group ( p=.009). For girls, there were no differences between groups in TV viewing, playing computer games, time spent on the computer, active transport, or sports and exercise. Overall, socio-economic status was largely unrelated to the key behaviours in this sample.
We conclude that:
- ethnicity and socio-economic status have little or no effect on our data, although given the distribution of the sample by ethnicity, this finding needs to be treated with some caution.
4www.msoc-mrc.gla.ac.uk/Publications/pub/Carstairs_MAIN.html