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RESEARCHARTICLE
Physical Education Increases Daily Moderate
to Vigorous Physical Activity and Reduces
Sedentary Time
KERLI MOOSES,MSc
aMARET PIHU, PhDbEVA-MARIA RISO, PhDcAAVE HANNUS,MSc
dPRIIT KAASIK, PhDeMERIKE KULL, PhDf
ABSTRACT
BACKGROUND: Physical activity (PA) is important to mental and physical health. Physical education (PE) lessons have the
potential to increase daily moderate to vigorous PA (MVPA) and reduce sedentary time (SED). We measured MVPA and SED
in primary school PE, determined the contribution of PE to daily MVPA and SED, and compared PA on days with and without PE.
METHODS: PA was measured in 504 first (ages 7-9) and second (ages 10-12) school level children for 1 school week, with
inclusion criteria of at least 10 hours of valid data. Linear mixed methods were used for data analysis.
RESULTS: In PE, students spent 28.6 ±16.5% in MVPA and 29.3 ±19.8% in SED. Each additional MVPA minute in PE was
associated with 1.4 more daily MVPA minutes. On days with PE, students had 12.8 (95% CI 10.5; 15.0) minutes more MVPA
and 9.7 (95% CI 16.3; 3.1) minutes less SED compared with days without PE.
CONCLUSIONS: Although MVPA in PE was relatively low and SED high, PE significantly increased daily MVPA and reduced
SED, confirming the important role of PE in supporting the healthy development of children.
Keywords: physical activity; physical education; sedentary time; moderate to vigorous physical activity (MVPA).
Citation: Mooses K, Pihu M, Riso E-M, Hannus A, Kaasik P, Kull M. Physical education increases daily moderate to vigorous
physical activity and reduces sedentary time. J Sch Health. 2017; 87: 602-607.
Received on January 24, 2016
Accepted on February 14, 2017
There is ample evidence that besides having a key
role in disease and obesity prevention physical
activity (PA) supports mental health and academic
achievement.1,2 To gain the necessary health benefits,
children and youth should accumulate at least
60 minutes of moderate to vigorous PA (MVPA) every
day.1,3 Furthermore, similarly to MVPA, sedentary
behavior has been shown to be an independent health
risk factor.4,5
The school has great potential in helping to
meet the PA guidelines and reduce sedentary time
among students. Whole school programs have been
suggested to be one of the best investments to increase
population-level PA.6On average, in-school PA
accounts for 30-40% of children’s total daily MVPA,7,8
aDoctoral Student, (Kerli.Mooses@ut.ee), University of Tartu, Jakobi 5, Tartu, Estonia 51014.
bLecturer, (Maret.Pihu@ut.ee), University of Tartu, Jakobi 5, Tartu, Estonia 51014.
cResearch Fellow, (Eva-Maria.Riso@ut.ee), University of Tartu, Jakobi 5, Tartu, Estonia 51014.
dResearch Fellow, (Aave.Hannus@ut.ee), University of Tartu, Jakobi 5, Tartu, Estonia 51014.
eProfessor, (Priit. Kaasik@ut.ee), University of Tartu, Jakobi 5, Tartu, Estonia 51014.
fLecturer, (Merike.Kull@ut.ee), University of Tartu, Jakobi 5, Tartu, Estonia 51014.
Address correspondence to: Kerli Mooses, Doctoral Student, (Kerli.Mooses@ut.ee), University of Tartu, Jakobi 5, Tartu, Estonia 51014.
Publication of this article was funded by Eesti Teadusagentuur (IUT 20-58).
with important input from physical education (PE)
lessons.9,10 At the same time systematic reviews reveal
that children spend less than 45% of total PE in
MVPA,11,12 which is less than the recommended
50%.13
Time spent in MVPA during PE varies according
to the measurement instruments. For example, time
spent in MVPA during PE has been reported to be
approximately 35% when measured objectively with
an accelerometer,11,12 whereas observational methods
have demonstrated 25% higher values.12 Many studies
focus only on MVPA in PE,10,14-16 and only few studies
using objectively measured PA data have explored the
sedentary time in PE.17-19 As sedentary time is an
independent health risk factor, there is a need for
602 •Journal of School Health •August 2017, Vol. 87, No. 8 •©2017, American School Health Association
more comprehensive understanding of sedentary time
during PE and the school day.
In addition, there is an ongoing debate whether
children compensate for higher school day PA
outside the school.20,21 According to the ‘‘activitystat’’
hypothesis, children have an energy expenditure set
point, and they therefore compensate for increased
PA in one part of the day by decreasing the PA of
another.22 According to this hypothesis, participation
in PE could reduce after-school PA. Earlier studies
concerning PE have concentrated only on the
contribution of MVPA on whole-day PA and have not
explored the possible compensation effect.14-16,18,23,24
As for the sedentary time, there is no consensus
on whether the amount of sedentary time on days
with and without PE is different.18,19 Considering the
contribution that PE has on students daily PA level,
more thorough information about the influence of PE
on daily MVPA and sedentary time and about possible
compensation effect is useful input when planning
interventions aiming to increase PA levels of students.
The purpose of the present study was therefore to:
(1) assess objectively measured PA and sedentary time
in primary school PE; (2) explore differences in PA and
sedentary time during PE between school level, sex and
body mass index (BMI); (3) determine the contributing
role of PE to daily MVPA and sedentary time; and (4)
compare PA on days with and without PE.
METHODS
Participants
A cross-sectional study was used to determine the
PA and sedentary behavior during 1 school week in a
sample on students from grades 1 to 2 (ages 7-9, first
school level) and grades 4 to 5 (ages 10-12, second
school level) in the period of December 2014 to May
2015. Out of 15 counties, the invitation to participate
in the study was sent to randomly chosen schools in
Estonia (2 counties on the islands were excluded due
to their location), with the criterion that no more than
2 schools from the same county were chosen. Schools
for children with mental or physical disability were
excluded from the study. The final sample included 13
schools (4% of all schools), children from 84 classes
and covered 60% of Estonian counties. All schools
were comparable in regards to the ethnic population.
The first school level had PE for 45 minutes 3 times
a week, boys and girls together, and in some schools,
PE was provided by a classroom teacher. In the second
school level, most students had PE twice a week for
45 minutes, whereas a few students had 90 minutes
once a week. In the second school level girls and boys
had separate lessons by a certified PE teacher with a
master’s degree.
Of those children who returned both the writ-
ten parental and student informed consent (57%,
N=819), a randomly chosen subgroup (N =636) was
formed for measuring PA with an accelerometer. The
randomization of subgroup was performed so that all
classes from selected grades were included into the
study. Current study is part of a larger study mea-
suring objective PA, anthropometry and psychological
determinants of PA of Estonian school children.
Instrumentation and Procedure
On the first measurement day, selected demo-
graphic and anthropometric measures were recorded
at school by a trained researcher. Height (Seca 213,
Seca GmbH, Hamburg, Germany) and body mass (A&D
Instruments, Abington, UK) were measured to the
nearest 0.1 cm and 0.1 kg, respectively. BMI was cal-
culated and children were classified as underweight,
normal weight, overweight, or obese according to
the International Obesity Task Force age-specific BMI
cutoff points.25
PA was measured with the ActiGraph GT3X
(ActiGraph LLC, Pensacola, FL) with 15-second
epochs. Participants were instructed to wear the
accelerometer for 7 consecutive days on the hip and
to retain their usual activity levels. It was advised to
remove the accelerometer for water-based activities
(eg, swimming, showering, etc). For the current
analysis, we only included days when the student
attended school. In addition, participants were asked
to fill in an accelerometer diary every day with the
times for the beginning and end of school days, PE,
organized sport, sleep, as well as the information
about the times and reasons for not wearing an
accelerometer. Children also reported the type of sports
they participated in. The parents were asked to help
their child in filling the accelerometer diary if needed.
Exact school timetables were obtained from school
personnel.
Data were downloaded from the accelerometer
and processed using ActiLife software version 6.11.2
(ActiGraph LLC, Pensacola, FL). Data were considered
valid if a minimum of 3 weekdays with at least 10 hours
of recorded data per day (hours awake) was present.
Zero counts of 20 minutes consecutive were classified
as non-wear time. All included students had at least
1 day with and 1 without PE. Exact time interval for
whole day, time spent in school, and in PE was based
on information from the accelerometer diaries and
school timetables. Minutes spent in MVPA, light and
sedentary activity were calculated using an Evenson
cutoff point for children.26,27
Data Analysis
Data are shown as means ±standard deviation,
unless stated differently. Depending on the normality
of data, a Mann-Whitney Utest or ttest, where
necessary, was used to identify sex differences
Journal of School Health •August 2017, Vol. 87, No. 8 •©2017, American School Health Association •603
on anthropometric and demographic variables. The
significance level was set at p <.05.
Multiple linear mixed models were used to explore
differences between school level, sex, and BMI with
PA in PE as an outcome variable. All analyses
were additionally adjusted for time spent in PE. To
explore the contribution of PE to daily MVPA and
sedentary time, 2 different models were used with
an outcome variable: (1) daily PA; and (2) sedentary
time. Models were adjusted for school level, sex, BMI,
time spent in PE, and hours awake. To determine the
differences between days with and without PE, daily
PA or sedentary time was an outcome variable, and
day (0 =non-PE day, 1 =PE day), sex, BMI, school
level, and participation in organized sport served as
independent variables. Linear mixed models were
used, as they enabled to take into account both
the nested structure and the repeated nature of the
data.28 We used 3-level models for all models, where
level 1 comprised days when students attended the
school, level 2 students, and level 3 schools. Schools
were included as the third level unit to control for
their possible effect on children’s PA. The statistical
significance of the model estimates was evaluated
using 95% confidence intervals.
Data were analyzed with the statistical program
R version 3.0.2 (http://www.r-project.org/), and for
linear mixed models the lme4 package was used.29,30
RESULTS
From the analysis, 132 children were excluded due
to: (1) accelerometer malfunction (N =19); (2) not
meeting the inclusion criteria (N =111); and (3) not
returning the device (N =2). Excluded children did not
differ from those entered into the analysis (N =504)
in terms of sex, BMI, and school level (p >.05).
A total of 944 days with PE and 1230 days without
PE were included into the analysis. The characteristics
of participants by sex and school level are shown in
Table 1.
In both school levels boys accrued more MVPA
minutes per day compared with girls. Almost a third
(28.3%) of the students were classified as overweight
or obese. In both school levels, more than half of the
children (52.3% and 61.3% in first and second school
level, respectively) participated in organized sport at
least once a week.
In PE students spent on average 28.6 ±16.5%
(13.0 ±9.3 minutes) in MVPA and 29.3 ±19.8%
(13.8 ±19.8 minutes) in sedentary activity. Only 4.2%
and 11.4% in the first and second school levels,
respectively, met the recommendation of 50% of PE
in MVPA (Figure 1).
Boys accrued 2.1 more MVPA minutes and 1.9 less
sedentary minutes in PE compared with girls (Table 2).
During PE more MVPA and less sedentary minutes
Table 1. Characteristics of the Participants
First school level Second school level
Boys Girls Boys Girls
N 138 128 110 128
Age (y ears) 7.9 ±0.6 7.9 ±0.7 11.0 ±0.8 10.8 ±0.7
Stature (cm) 1.35 ±0.07 1.33 ±0.07* 1.51 ±0.09 1.50 ±0.09
Body mass (kg) 33.2 ±8.8 30. 1 ±5.9* 45. 9 ±13.3 43.3 ±11.6
Body mass index
(kg/m2)
18.0 ±3.2 17. 0 ±2.3* 19.8 ±4.1 19.1 ±3.9
Dail y MVPA
(minutes/day)
73.3 ±34.7 67.1 ±33.9* 66.6 ±36. 4 55.5 ±29. 4*
Daily sedentary time
(minutes/day)
447.3 ±84.4 447.7 ±77.4 498.9 ±88.9 524.8 ±88.3*
*Significant differences between sexes (p <.05).
MVPA, moderate to vigorous physical activity.
Figure 1. Percentage of Time Spent in Moderate to Vigorous
Physical Activity during Physical Education Lesson by Sex and
School Level. Note. The vertical line is the recommended 50%.
Black, first school level; gray, second school level; solid line,
boys; dashed line, girls
were accrued in the second compared with the first
school level. There was no difference in time spent
in sedentary activity and MVPA during PE in terms
of BMI.
Each additional MVPA minute in PE was associated
with a 1.4-minute increase in daily MVPA (Table 2).
Both boys and girls accrued significantly more MVPA
during days with PE than on days without PE
(Figure 2). Regression analysis revealed that on days
with PE, students had 12.8 (95% CI 10.5; 15.0)
minutes more MVPA and 9.7 (95% CI −16.3; −3.1)
minutes less sedentary time compared to days without
PE when controlled for organized sport participation
after school.
DISCUSSION
The purpose of this study was to assess objectively
measured PA and sedentary time in PE and the
contributing role of PE on daily PA. First, we found that
604 •Journal of School Health •August 2017, Vol. 87, No. 8 •©2017, American School Health Association
Table 2. Physical Activity During Physical Education Lessons and on Days With Physical Education
PE MVPA PE sedentary Day MVPA Day sedentary
β(95% CI) β(95% CI) β(95% CI) β(95% CI)
Sex −2.1 (−3.2; −1.0) 1.9 (0.7; 3.2) −6.5 (−11.1; −2.0) 9.2 (−0.8; 19.1)
School level 1.9 (0.7; 3.0) −2.7 (−4.0; −1.4) −10.7 (−15.5; −6.0) 65.2 (54. 7; 75.8)
BMI −0.2 (0.4; 0.0) 0.0 (−0.2; 0.2) −0.8 (−1.4; −0.1) 0.3 (−1.1; 1.8)
PE MVPA 1.4 (1.1; 1.6)
PE sedentary 1.4 (1. 1; 1.8)
Girls and the second school level served as the reference.
PE, physical education; MVPA, moderate to vigorous physical activity; BMI, body mass index.
Figure 2. Moderate to Vigorous Physical Activity on Days With and Without Physical Education in First (A) and Second (B) School
Level by Sex. Note. Gray, moderate to vigorous physical activity in the physical education lesson. *Significant difference between
days with and without a physical education lesson, p <.05
students spent only a third of PE in MVPA and another
third in sedentary. Second, despite the relatively low
PA levels, PE still contributed significantly to daily PA.
Third, on days with PE, students had more MVPA
and less sedentary time compared with days without
PE. This study adds new insight to the limited body
of evidence on the effect of PE on daily PA and
sedentary time using objective measures of PA. Also
it supplements the existing research concerning the
levels of PA and sedentary time in PE.
According to previous studies, the proportion of
time students spent in MVPA in PE is low - reviews
involving both observational and objective methods
suggest that 34-47% of PE is spent in MVPA.11,12,31 At
the same time, the objectively measured MVPA in PE
tends to be up to 25% lower compared to observational
methods.12 Some studies using objectively measured
PA data have shown that MVPA in PE is even
below 13%.14,17 The current finding that students
spent almost a third of PE in MVPA is in line with
a recent study involving a representative sample
of Swiss students, which reported 33% of PE in
MVPA.10 Indeed, only 8% of students in our study
reached the recommended 50% of PE in MVPA,
which is substantially lower than the 14% and 42%
reported by others10,19 and drastically far below the
recommendation. As for the sedentary time, students
spent almost a third of PE as physically inactive,
whereas in previous studies sedentary time has
accounted for approximately 18% of PE time.17-19
One finding emerging from our analysis is that
the proportion of MVPA in PE was relatively low
and the proportion of sedentary time was high. As
for many students PE is the only opportunity for
organized PA, there is a need for supporting and
improving the quality of PE. Previous studies suggest
that substituting sedentary time in PE with light
activity and increasing time spent in MVPA could
be achieved through professional teacher training
to improve lesson preparation and management,32
enabling adequate number of PE teacher per student
and appropriate PE equipment and facilities.33
Although PA decreases and sedentary time increases
with age,34 in the current study students from the first
school level spent less time in MVPA and more in
sedentary during PE compared with the second school
level. This tendency has also been documented before
and explained by enhanced motor development,
perceived competence, and access to a wider range of
physical activities in older school age.11 In the current
study, we can hypothesize that the training of the
teachers could also have some impact on PA levels,
as in first school level the PE was mostly organized
by the class teacher, while in the second school level
by a qualified PE teacher. It has been shown that
specialist-taught PE can significantly increase the time
Journal of School Health •August 2017, Vol. 87, No. 8 •©2017, American School Health Association •605
spent in MVPA.32,35 As for the sex, our findings are
in accordance with previous studies,10,19 where boys
accrued more MVPA minutes in PE than girls.
One of the issues emerging from our findings is that
in spite the relatively large proportion of sedentary
time and small proportion of MVPA, PE still had an
important influence on PA for the entire day. Each
additional MVPA minute in PE was associated with
an additional 1.4 minutes of total daily MVPA. In light
of the ‘‘activitystat’’ hypothesis,22 our results confirm
that children do not compensate extra PA in school
by reducing PA outside school.10,19,21 Furthermore,
on days with PE, students had 12.8 minutes more
MVPA on days without PE, which is in line with
previous studies.10,16 The strength of the present study
compared with previous studies is that we additionally
controlled for organized sport participation. This
enabled us to determine the contribution of PE and
confirm that higher MVPA on days with PE compared
to days without PE is not due to organized sport
participation. As for the differences in sedentary time,
students had 9.7 minutes less sedentary time on days
with PE compared with days without PE. The current
findings concerning sedentary time are contradictory,
with some reporting no difference between days
with and without PE,19 while others confirm reduced
sedentary time on days with PE.17,18,36
Overall, these findings highlight the importance
of PE in the perspective of children’s healthy
development and support the notion that PE should be
offered every school day. Existing research recognizes
the critical role played by PA concerning the physical
and mental well-being.1,2 The positive influence of PA
on health is also present in PE. The favorable effect
of daily PE has been shown in several studies and
interventions, where in addition to the increase in daily
MVPA, favorable changes in BMI and cardiovascular
risk factors,35,37,38 daily PA habits,38 physical fitness38
and academic performance39 have also been apparent.
Limitations
One limitation of this study is that although
ActiGraph accelerometers have been shown to be valid
in measuring the PA of children,26,27 there are some
activities that are not well detected, and therefore PA
levels in the current study could be underestimated.
However, the presence of such activities is expected to
be minimal in PE.
The study is also limited by the lack of information
on PE content. It has previously been shown that most
MVPA is accrued in team games and less during move-
ment (eg, dance and gymnastics) activities.9Therefore,
future research should combine objective PA mea-
surements with information about lesson content.
In addition, in the current study, the possible sea-
sonal effects on children PA have not been controlled
for. Previously it has been shown that children are
more physically active during spring/summer months
compared with the autumn/winter months.40 At
the same time, the PA levels during recess are not
influenced by the season.41 Therefore, whether PA
in PE lesson is influenced by season warrants further
investigation.
Conclusions
Although students have an alarmingly great amount
of sedentary time during PE and only a third is spent
in MVPA, PE still contributed significantly to daily
MVPA and reduced daily sedentary time. Furthermore,
additional MVPA during PE was associated with
higher daily MVPA. These findings enhance our
understanding of the great importance of PE in the
health perspective of children and show that PE is
a promising instrument in supporting daily PA and
reducing the sedentary time of students.
IMPLICATIONS FOR SCHOOL HEALTH
This research has several practical implications.
First, it points to the significant contribution of PE on
the PA levels of children. At the same time, PA in PE is
relatively low, as only a third of PE is spent in MVPA.
The results also confirm that girls accrue less MVPA
during PE, which indicates the need for a gender-based
approach. As PE is the only subject in school where
students can be physically active and which teaches
motor skills necessary for lifelong PA, more emphasis
should be placed on teacher training which helps to
increase time spent in MVPA and ensure the lesson
quality. This study also indicates that increasing the
number of PE lessons could be an effective way to help
the students reach the necessary levels of daily PA.
Human Subjects Approval Statement
The study was approved by the Ethics Committee
of the University of Tartu.
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Journal of School Health •August 2017, Vol. 87, No. 8 •©2017, American School Health Association •607
