Biology Reference
In-Depth Information
spent by adolescents in moderate to vigorous PA decreased significantly
from 87 to 50 min/day over a 5-year period; the time spent in sedentary
behaviors increased from 512 to 600 min/day (
Trang et al., 2012
).
With regard to the PA levels among adolescents in Hong Kong,
Lee et al.
(2005)
reported that 65% of the adolescents participated in vigorous exercise
for at least 20 min a day for less than 3 days a week. This finding is partic-
ularly true among the girls and those students in higher grades in school.
Even for moderate exercise, only approximately 13% of the adolescents were
found to participate for at least 30 min a day more than 5 days a week.
In Macao, only a small percentage of the school-age children (5.7%) and
adolescents (4%) were reported to have engaged in moderate exercise for
the children and adolescents spent over 2 h daily on sedentary activities, such
as watching television, playing video or computer games, and using the
computer for nonacademic purposes. Similar patterns of PA and sedentary
behavior were reported among adolescents in Taiwan; a national health sur-
vey found that only 28.4% of the adolescents met the PA guidelines, whereas
nearly 80% of the adolescents reported being sedentary for more than 8 h a
day (
Chen, Haase, & Fox, 2007
)
. Similar to other countries, girls were found
to be more sedentary than boys.
Levy, and Cuevas-Nasu (2009)
reported that the adolescents in Mexico are
generally sedentary and tend to spend more time on screen-based activities
than PA. This result aligns with what had been recorded in a previous lon-
gitudinal study, in which the median time of television watching among
Mexican adolescents was 3.90 h/day and only a minimal amount of time
was dedicated to vigorous- (0.73 h/day) and moderate-intensity (0.58 h/
day) PA (
Caballero et al. 2007
). Similar findings have also been reported
in Saudi Arabia, where only approximately half of the male and less than
a quarter of the female adolescents met the current PA recommendation
of 1 h daily of moderate-intensity PA (
Al-Hazzaa, Abahussain, Al-Sobayel,
Qahwaji, & Musaiger, 2011
)
. This result was also supported by previous
studies that involved objective methods of PA measurement, in which it
was found that 60% of the children and 71% of the adolescents did not engage
in any health-enhancing PA for a sufficient duration and frequency
(
Al-Hazzaa, 2002
)
.
Ng et al. (2011)
also reported that the proportion of
Emirati girls engaged in moderate PA (53%) and vigorous PA (77%) was
significantly less than boys (63% for moderate PA, 81% for vigorous PA).
The authors also found that the majority of the Emirati girls (75%) tended
