The Effectiveness ofInterventions to Increase
Physical Activity among
Elementary SchoolChildren in Okinawa,
Japan
University of the Ryukyus

Minoru TAKAKURA
Faculty of Medicine, University of the Ryukyus
Okinawa, Japan(minoru@med.u-ryukyu.ac.jp)

Minoru KOBAYASHI
Faculty of Education, University of the Ryukyus

Okinawa, Japan

Atsushi KURIAHRA
Faculty of Culture & Education, Saga University

Saga, Japan

Yosiaki SASAZAWA
Faculty of Education, University of the Ryukyus

Okinawa, Japan

University of the Ryukyus

BackgroundPurposeRecently, physical inactivity anddecline in physical fitness arebecoming common and serious
problems among young Japanesepeople. There is a need to improvephysical activity and reduce sedentary
behavior in childhood and adolescenceto prevent lifestyle-related diseases
later in life.

The aim of this study was to determine
improvements in the levels of physicalactivity and physical fitness of children
by conducting various interventions,while taking into account theparticularities of the designated area.

University of the Ryukyus

Methods

University of the Ryukyus

Okinawa prefecture¾ Participants¾2 elementary schools in the town ofTaketomi of Okinawa, Japan
zExperimental group (age 6-12)
47 students (25 boys, 22 girls)
zControl group (age 6-12)
50 students (23 boys, 27 girls)¾ Duration

Iriomote Island,Taketomi¾June-November 2005
University of the Ryukyus

Study area: Taketomi, Okinawa
University of the Ryukyus

1Outcome measures

Pre-test¾ Physical fitness levels¾ Total physical fitness score measured with
the Japanese New Physical Fitness Test

¾ Body fat percentage¾ Measured with ultrasound instrument(Aloka SSD-900)

5-monthintervention

Experimentalgroup

Controlgroup¾ Physical activity levels¾ Step counts, activity energy expenditure,and total energy expenditure during school
hours measured for 8 continuous days byaccelerometers (Suzuken Lifecorder EX)

Post-test

Research Outline

University of the Ryukyus

University of the Ryukyus

Existing view on intervention

Intervention Programs

It is inferred that in cases where adults,
particularly parents, place value andimportance on physical activity andencourage children to do so, that the child’slevel of participation in physical activities
will increase (Sallis & Nader, 1988).

1. Self-Management

It is important to encourage physicalactivity not only in children, but also in otheradults.

¾ Issued accelerometers and log sheets, and had
the participants record the amount of walking,exercise, and energy expenditure (Children andguardians).
¾ Had guardians report weekly by e-mail on
physical activity, and provided them withinformation on ways to maintain and improve
activity levels.

2. Evening Beach Walks¾ Conducted walks on the beach every
Wednesday and Saturday (Children, guardians,and teachers).

University of the Ryukyus

3. School-based health education¾ Conducted a lesson to help children recognize
the importance of leading a physically active life
during childhood (conducted once).

4. Recruitment of staff to play with children¾ Had staff play with children between classes
and after school in order to encourage them tospend time in the schoolyard (conducted for thefirst 3 weeks).

5. Recruitment of a snorkeling instructor
and supply of swimming/snorkeling
equipment (conducted for 1 month).
University of the Ryukyus

University of the Ryukyus

Results
In the area of body fat percentage, there
were no significant differences in the trends
exhibited by the experimental and control
groups.
However, the experimental group showed asignificant increase in physical fitness score,
as well as all three areas of physical activity;
total step counts, activity energy expenditure,and total energy expenditure, while thecontrol group showed no significant changes.
University of the Ryukyus

2Discussion

Exp.

（score）

In the area of body fat percentage, bothgroups showed higher results in the post-test
than in the pre-test. It is possible that this result
may be attributed to the subtropical climate of
the region in which the test was performed. The
pre-test period was marked by hightemperatures and humidity, which may havedecreased the appetites of the subjects,resulting in a lower body fat percentage. Whenthe post-test was conducted, temperatures andhumidity were lower, possibly resulting inincreased appetites and body fat percentage.

Con.

50

46.3
45.2

45p=.217

40Group p=.650
Timep<.001
G*T
p=.015

39.7

Simple main effects
Exp. (pre-post) p<.001
Con. (pre-post) p=.271

35Pre

Post

Means of physical fitness score at pre- and post-test（repeated measures ANOVA）

University of the Ryukyus

Exp.

（steps）

11000

10000

Con.

Exp.

Con.

250
Group p=.005
Timep<.001
G*Tp<.001

Simple main effects
Exp. (pre-post) p<.001
Con. (pre-post) p=.183

200

223

Simple main effects
Exp. (pre-post) p<.001
Con. (pre-post) p=.916

p<.001

9000

8000

University of the Ryukyus（kcal）

10980

Group p=.002
Time
p<.001
G*T
p<.001p=.705

43.6

150

8195
7846

p=.566p<.001p=.414

139
126

127

7287
7000

100

Pre

Post

Pre

Means of total step counts at pre- and post-test（repeated measures ANOVA）

Post

Means of activity energy expenditure at pre- andpost-test （repeated measures ANOVA）

University of the Ryukyus

Exp.

（kcal）Con.

Exp.

（%）

1800

Con.

20.0
Group p=.162
Time
p<.001
G*T
p=.005

1700

University of the Ryukyus

1770

19.2

19.0

Simple main effects
Exp. (pre-post) p<.001
Con. (pre-post) p=.270

18.5
p=.037

18.0
17.0

1600

18.0
17.3
Group p=.992
Time
p=.004
G*T
p=.094

1590
p=.749

1568
1547

16.0
15.0

1500

Pre

Post

Means of total energy expenditure at pre- and posttest （repeated measures ANOVA）
University of the Ryukyus

PrePostMeans of body fat percentage at pre- and post-test（repeated measures ANOVA）
University of the Ryukyus

3Conclusion ＆ Issues for further study
This study shows that conducting various
interventions involving adults, such as parents,
can contribute to an improvement in thephysical activity levels and physical fitness
scores of children.
In future studies, it would be useful to conduct
interventions in various different regions, aswell as improve the design of the study, forexample by designing the study period so thatthe pre-test and post-test would be less affectedby climatic differences.

Health Education

University of the Ryukyus

Evening Beach WalksUniversity of the Ryukyus

University of the Ryukyus

Children playing in the schoolyard
University of the Ryukyus

Snorkeling Practice University of the Ryukyus

4