the relationship between modern media and physical activity in western australian children
owen carter
senior research fellow
centre for behavioural research in cancer control
curtin university of technology
“sedentary activities such as watching television are strongly associated with excessive adiposity and displaces time for physically active pursuits”
Trost, S. (2005 p.73)
Discussion paper for the development of recommendations for children's and youths‘ participation in health promoting physical activity
Doctors say the results show the problem of excessive screen time is so widespread that children's use of the media must be considered a serious public health issue
…so engrossed in sedentary screen-based recreation that it reduces their involvement in sport, music and other leisure pursuits.
Her results, published in the Journal of Paediatrics and Child Health, come from a study of 2750 children revealing big weight gains in children and adolescents despite improvements in physical fitness
although there had always been a significant percentage of children who watched a lot of TV, the proportion spending two hours or more watching the set or computer was rising
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
Hou
rs p
er d
ayaverage hours spent using various modern media
amongst WA children
15 min
Gaming
24 min
Computer
2 hrs
4 min
TOTALSCREEN
USE
1hr
6 min
TV
20 min
Videos/DVDs
screen hours per day
14131211109876543210
60.2% 39.8%
total screen time per day
daily screen time vs. frequency of physical activity
0 10 20 30 40 50 60 70 80 90 100 110
physically active behaviours
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
scre
en h
ours
per
day
r(1,858)=.065 p<.005 R2=.04%
2 hrs
t(1,858)=1.507 p=NS
<2 hrs 2+ hrs
9.88 10.81
meta-analysis: screen time and physical activity
• 39 independent samples• pooled N = 141 505• effect size between TV and PA:
-0.096“too small to be of clinical relevance”
• screen time alone unlikely to explain relationships between sedentary behaviour and health
32˚S
Mid
nigh
t
2:00
AM
4:00
AM
6:00
AM
8:00
AM
10:0
0 A
M
12:0
0 P
M
2:00
PM
4:00
PM
6:00
PM
8:00
PM
10:0
0 P
M
Mid
nigh
t
Sho
wer
Get
dre
ssed
Bre
akfa
stT
RA
NS
IT
TR
AN
SIT
Din
ner
SLEEPSLEEP
Ho
mew
ork
14 hrs1.5 hrs 2.5 hrs
SCHOOL
Scr
ee
n t
ime
5.5 hrs
“displacement hypothesis”(36%)
introduction of television (Norwich 1956)
introduction of television (Perth 1959)
1959 1960
TV - 16 hrs
Radio 7 hrs 42 min 54 min
Cinema 3 hrs 48 min
Sport 2 hrs 12 min 2 hrs 34 min
“Television’s most powerful rivals are outdoor play and unorganised social activities”
1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 20100
1.0
2.0
3.0
scre
en h
ours
per
day
Norwich1956
Perth1961
WA2003
Australia2006
539 studies from 1949-2004
viewing times stable for past 50 years ~2 hrs/day
• CAPANS data consistent with international data• screen time remains intractably stable• screen time likely to displace other sedentary behaviours• children have time for both physical activity and screen time• human behaviour more complicated than single factors• we are not the first generation to idolise the past
conclusions
Ariel Rhiannon Carter(4 years)
Sage Tiberius Carter(3 years)