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Educating the Student Body
FIGURE 2-12 
Hours per day spent watching television by age group, 1998-2009, and hours 
per day spent watching television and using computers for youth aged 8-18.
NOTES: TotTV = total television content, which includes watching not only standard televi-
sion programs but also prerecorded shows, DVDs, and television content on other platforms 
(e.g., Internet, cell phone, iPod); Comp = does not include time spent using a computer for 
schoolwork.
SOURCES: Rideout et al., 2010; TVB, 2012. 
Figure 2-12.eps
0
1
2
3
4
5
88
90
92
94
96
98
Year
00
02
04
06
08
10
Mean 
Hours 
per 
Da
y
Teens
Children
TotTV8-18
Comp8-18
with whom they were compared (Hairston et al., 2012). This translates to 
87 minutes per day of sedentary physical activity.
Declines in cardiorespiratory fitness among children around the world 
have been documented. American researchers usually have preferred not 
to compare current measures of cardiorespiratory fitness among American 
children with results of surveys from previous years because of differing 
measurement methods (Pate et al., 2006a), although one review has sug-
gested declines since the 1960s (Malina, 2007). Assessments have been 
performed, however, in other countries using more consistent measurement 
techniques, and they indicate a global decline in cardiorespiratory fitness 
among youth (Santtila et al., 2006; Tomkinson and Olds, 2007; Albon et al., 
2010; Boddy et al., 2012; Tomkinson et al., 2012) or, in one case, a decline 
in physical activity behaviors (Salmon et al., 2005) (see Table 2-2). A review 
of evidence from around the world found that participation by youth in 
“active transport, physical education, and organized sports is declining in 
many countries” (Dollman et al., 2005, p. 892). The authors also comment 
that “young people would like to be active but are constrained by external 
factors such as school policy or curricula, parental rules in relation to safety 
and convenience, and physical environmental factors” (p. 892).

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Educating the Student Body: Taking Physical Activity and Physical Education to School
Status and Trends of Physical Activity Behaviors and Related School Policies
 
69
TAbLE 2-2 Declines in Physical Fitness Among Children Around the World
Source
Location
Time 
Period
Age 
Range
Method of 
Assessment
Findings
Boddy et al. 
(2012)
United Kingdom
1998-
2010
9-10.9 
years 
(cohort)
20-m shuttle 
run
1.8% decline 
per year
Tomkinson 
et al. (2012)
Asia (China, 
Japan, S. Korea, 
Singapore)
1964-
2009
9-17 
years
Long-distance 
running time
16% decline
Santtila et 
al. (2006)
Finland
1975-
2004
20 
years
12-min run
8% decline
Albon et al. 
(2010)
New Zealand
1991-
2003
10-14 
years
550-m run
1.6% decline 
per year
Salmon et 
al. (2005)
Australia
1985-
2001
9-13 
years
Walking trips 
to school
Taking physical 
education 
classes