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The Physical Activity of Estonian Primary SchoolChildrenLennart Raudsepp & Peep PällPublished online: 07 Jul 2006.

To cite this article: Lennart Raudsepp & Peep Päll (1999) The Physical Activity of Estonian Primary School Children, EuropeanJournal of Physical Education, 4:1, 65-74, DOI: 10.1080/1740898990040105

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European Journal of Physical Education, 1999, 4, 65-74

The Physical Activity of EstonianPrimary School Children

Lennart Raudsepp and Peep Päll

The aim of this study was to provide an estimate of the physical activity levels ofEstonian primary school children. The subjects were 174 7- to 9-year-old children(83 boys and 91 girls). Physical activity was assessed by (a) parental seven-dayphysical activity recall and (b) Caltrac accelerometers (Hemokinetics Inc., Madison,WI). Caltrac accelerometers were worn between the hours of 8.00 a.m. and 8.00p.m. during one schoolday and one weekend day and mean activity counts of theCaltrac score for the two days were calculated. According to the results of the seven-day activity recall, the moderate-to-vigorous physical activity (MVPA) levels of theboys were significantly (p<0.05) higher than the girls in all age groups. The 54.2 to99.4 minutes (9-year-old girls and 7-year-old boys, respectively) of daily MVPAmeet recent Physical Activity Guidelines for Adolescents. The results of the Caltracmonitoring indicated that there were no gender differences in the activity counts of7-year-old children. However, the mean Caltrac scores of the boys weresignificantly higher than the girls in the 8- and 9-year-old groups. In addition, theresults indicated a significantly (p<0.05) higher level of MVPA in rural comparedwith urban schoolchildren. It was concluded that the level of MVPA of Estonianprimary school children was sufficient to meet recent activity guidelines foradolescents. Boys were generally more physically active than girls of the same age.

INTRODUCTION

Research evidence clearly demonstrates that physical activity is a prerequisite foroptimal growth and development of children and adolescents. Thus it is notsurprising that physical activity levels of children and youth have become animportant issue for educators, physicians, public health authorities and parents(Aaron et al., 1993). Childhood physical activity is positively associated with arange of beneficial childhood health and fitness outcomes (Rowland, 1990) and alsohas potential for fostering attitudes, skills, and habits that may increase thelikelihood of regular exercise during adult life (Sallis et al., 1992).

The aims of physical education include the fostering of an interest in physicalactivity outside and beyond school. The adoption of an active lifestyle throughoutchildhood and adult life is encouraged to enable the individual to use leisure timefor activities which are not only satisfying and enjoyable, but which may alsocontribute to improved health by enhancing or maintaining fitness (Williams, 1988).Despite acknowledgement of the need to examine children's physical activitypatterns, relatively little is known about children's participation in physical activity(Parcel et al., 1987; Pate et al., 1994). However, there is general agreement that thephysical activity levels of children and youth have declined during past decades

Lennart Raudsepp and Peep Pall are with the Institute of Sport Pedagogy, University ofTartu, Tartu, Estonia.

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(Sallis, 1993; Armstrong, 1995). Several researchers (Williams, 1988; Armstrong,1989; Pate et al., 1994) have expressed the view that children's activity levels mayhave declined to such an extent as to be detrimental to health.

In the absence of available research on children, past recommendationspromoting physical activity for children and adolescents were based on adultresearch (Killoran et al., 1994; Myers et al., 1996). Killoran et al. (1994), havingrecently reviewed the literature on appropriate activity for adults, recommend 30minutes of moderate to vigorous physical activity on at least five days per week.However, physical activity guidelines for adolescents have been developed. TheInternational Consensus Conference on Physical Activity (Sallis and Patrick, 1994)established two major guidelines for physical activity in adolescents as follows:

1. All adolescents should be physically active daily, or nearly every day, as partof play, games, sports, work, transportation, recreation, physical education, orplanned exercise in the context of family, school and community.

2. Adolescents should engage in three or more sessions per week of activities thatlast 20 minutes or more at a time and that require moderate to vigorous levels ofexertion.

Several studies investigating the activity level of elementary school children havebeen conducted (Simons-Morton et al., 1990; Armstrong and Bray, 1991; Sleap andWarburton, 1990, 1996; Sallo and Silla, 1997). For example, Baranowski et al.(1987) observed the physical activity of third to fifth grade children and found that10.4% of children engaged in at least one MVPA (20 mins continuous aerobicexercise) daily. Sleap and Warburton (1994) studied the physical activity patterns ofBritish primary school children and found that they participated in very littlevigorous physical activity. Armstrong and Bray (1991) investigated the physicalactivity patterns of primary school children using heart rate monitoring. The resultsrevealed that few children experienced the volume of physical activity associatedwith an improvement in cardiopulmonary fitness. Similar findings were alsoreported by Simons-Morton et al. (1990) in a study of, Texas elementary schoolchildren. However, the research evidence is limited and far from comprehensive.

The assessment of physical activity in children is complicated since most methodslack precision and validity. A host of methods have been used in an attempt to measurechildren's physical activity including self-report, direct observation, heart raterecording, motion sensors and doubly-labelled water (Saris, 1986). The assessment ofactivity in primary school children is complicated also by the fact that young peopleare unable to recall and/or record activity accurately. Moreover, their patterns ofactivity fluctuate more than those of adults, making activity profiling difficult(Freedson, 1989). Saris (1986) suggests that a combination of methods be used, withthe specific techniques chosen depending on the number of subjects being studied.

This study was designed to examine the physical activity of Estonian primaryschool children as determined by a seven-day recall questionnaire and the Caltracaccelerometer. In addition, rural and urban differences in children's physical activitypatterns were examined.

METHODSubjects

One hundred and seventy four primary school children (aged 7-9 years) participatedin the study. The subjects were drawn from three randomly selected schools from

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the city and county of Tartu, Estonia. According to the regular (twice per schoolyear) school medical examination, all recruited children were healthy andparticipated regularly in the school physical education programme twice a week.The parents of each child were informed about the testing procedures, and theyconsented to their child's participation in the study.

Procedure

Physical activity was assessed by a 7-day physical activity recall questionnairewhich was modified from Godin and Shephard (1986) and the Caltrac accelerometer.In the present study, the children's parents recorded how much time (hours andminutes) their child spent on various activities outside school every day for oneweek. The written completion of the 7-day activity recall by parents for children'sdaily activities took 10-15 minutes every evening. Activities were classified as low(3 METs), moderate (5 METs), or vigorous (9 METs) and added to the recallquestionnaire. Activities were classified using the compendium of physical activitiescompiled by Ainsworth et al. (1994). This compendium has been developed tofacilitate the coding of physical activities and to promote comparability of codingacross studies. The energy costs of activities listed in the compendium wereestablished following a review of published data. Energy expenditure in kilocaloriesor kilocalories per kilogram body weight can be estimated for all activities. Specialattention was given in the 7-day physical activity recall to MVPA, such as gamesand sports activities. After data collection the following measures were computedfrom the activity recall: Total weekly physical activity (hours per week); totalweekly MVPA (moderate plus vigorous activities during one week); low intensityphysical activity (hours per week), and mean daily MVPA (total weekly MVPAdivided by 7 and expressed as minutes per day).

Caltrac accelerometers (Hemokinetics Inc., Madison, WI) were worn betweenthe hours of 8:00 a.m. and 8:00 p.m. during one schoolday and one weekend day.The children's parents were instructed to put the Caltrac on at 8:00 a.m. in themorning and to record the reading and remove the Caltrac at 8:00 p.m. Allmonitoring occurred from Monday through to Thursday (schooldays) and Saturday(weekend day). During the same week the parents reported their child's physicalactivities using the 7-day recall questionnaire. The accelerometers wereprogrammed to measure only body movement without regard to age, weight orgender. The score thus reflects only the child's body movements and the intensity ofthat movement. It does not reflect estimated energy expenditure.

Anthropometric measures

Stature was measured using Martin's metal anthropometer to the nearest 0.1 cm andbody mass was measured to the nearest 0.1 kg using medical scales.

RESULTS

Anthropometric measures and physical activity according to intensity level acrossage and sex groups (7-day recall) are presented in Table 1. Total weekly physicalactivity during one week was significantly (p<0.05) higher in boys than girls in the7- and 8-year groups but not at 9-year-old. There were no significant (p>0.05) sex

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Table 1: Descriptive data and physical activity according to intensity level (7-dayrecall).

Height (cm)

Weight (kg)

LPA(hAveek)

TPA (h/week)

7-year-olds

Boys(n=31)

125.8 (7.6)

25.5 (5.2)

14.6 (3.2)

26.2 (3.8)

Girls(n=30)

125.2 (8.1)

24.2 (4.8)

14.1 (3.6)

22.7 (3.4)*

8-year-olds

Boys(n=27)

131.3 (7.2)

28.4 (5.5)

13.7 (3.1)

23.8 (3.6)

Girls(n=29)

130.4 (7.8)

26.3 (5.1)

14.1 (3.6)

21.6 (3.3)*

9-year-olds

Boys(n=31)

136.6 (7.4)

31.8 (5.4)

11.7 (2.5)

19.9 (3.1)

Girls(n=26)

134.8 (7.2)

30.3 (4.9)

13.2 (3.2)*

19.5 (3.3)

Values are mean (SD)

* p<0.05 Boys vs girls within age group

LPA- low intensity physical activity; TEA- total weekly physical activity

differences in anthropometric measures. The mean daily MVPA scores across age andsex groups obtained by the 7-day recall questionnaire are presented in Figure 1. Boysperformed significantly more (p<0.05) minutes of daily MVPA than the girls in all agegroups. The results also indicated significant (p<0.05) decreases in physical activitywith age in both sex groups. The results of the Caltrac monitoring (mean activitycounts for one schoolday and one weekend day) across age and sex groups are shown

Figure 1: Daily MVPA of children (7-day recall) * p<0.05

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in Figure 2. There were no significant sex differences in the activity scores of 7-year-old children. In the 8-and 9-year-old groups, boys performed significantly more(p<0.05) physical activity than girls of the same age. Figure 3 shows the mean valuesof MVPA between rural and urban children. The results revealed significantly higher(p<0.05) levels of MVPA in rural compared with urban schoolchildren.

Figure 2: Physical activity of children (Caltrac) * p<0.05

Figure 3: MVPA of rural and urban children (7-day recall) * p<0.05

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DISCUSSION

It is widely acknowledged that children and youth need regular physical activity fornormal growth and development, and maintenance of good health and fitness (Pateet al., 1994). However, relatively little is known about children's participation inphysical activity (Parcel et al., 1987; Pate et al., 1994). There is general agreement thatthe physical activity levels of children and youth have declined during past decades(Williams, 1988; Pate et al., 1994; Armstrong, 1995). The purpose of the present studywas therefore to examine the physical activity patterns of Estonian primary schoolchildren as determined by 7-day parental recall and the Caltrac accelerometer.

The activity levels of children have not been widely researched (Simons-Mortonet al., 1988) although Cale and Almond (1992) concluded from a review of twentystudies that young children were not sufficiently active. In addition, the optimalamount of MVPA for children is unknown, but some experts recommend at leastsome MVPA daily (Simons-Morton, 1988). The 54.2 to 99.4 minutes (third-gradegirls and first-grade boys, respectively) of daily MVPA reported by the parents ofelementary school children in this study is generally consistent with previoussurveys (Ross and Gilbert, 1985; Simons-Morton, 1990, 1997). The mean valuesmet or exceeded the guidelines for physical activity proposed by the consensusconference (Sallis and Patrick, 1994). These provide an amount of physical activitythat is adequate for health maintenance for adolescents. Although these guidelineshave been developed specifically for adolescents, it is interesting to analyze whetherthe primary schoolchildren's activity met established recommendations. Inconsidering the more stringent guideline of the International Consensus Conference(Guideline 2), which states that adolescents should engage in three or more sessionsper week of activities that last 20 rnin or more at a time and that require MVPA, itappears that the primary school children participating in the present study meet thisguideline. The rationale provided for this guideline is the evidence that regularparticipation in MVPA enhances physiological health, increases HDL cholesteroland increases cardiorespiratory fitness (Sallis and Patrick, 1994). Furthermore, theamount of daily MVPA reported in this study is higher than the amount typicallyreported in other studies which have assessed children's physical activity by othermethods such as heart-rate monitoring (Armstrong and Bray, 1991; DuRant et al.,1992; Gilbey and Gilbey, 1995) and by direct observation (McKenzie, 1991; Sleapand Warburton, 1994). The results of a more recent study by Sleap and Warburton(1996) which investigated the physical activity levels of 5-to 11-year-old children inEngland showed that preadolescents engaged in MVPA for an average of 117minutes or 8% of a 24 hour day. Nevertheless, despite almost two hours of MVPAdaily, the authors stated that although some preadolescent children appear to bequite active, the overall picture shows that most children engage in very littlesustained, playful physical activity.

The descriptive data of sex differences in physical activity in this study wereconsistent with previous research findings (Eaton and Enns, 1986; Baranowski etal., 1993; Sallis, 1993). The results from the activity recall indicated that boys spent16-25 more minutes per day on moderate to vigorous physical activity than the girls.Although boys are generally more active than girls, little is known about thepossible reasons for this. It has been suggested however that boys seem to spendmore time in activity-enhancing environments than girls (Baranowski et al., 1993).In addition, boys and girls have also been found to engage in different types ofactivities (Faucette et al., 1995). It is also well documented that boys spend moretime than girls in higher-intensity activities (Aaron et al., 1993; Faucette et al., 1995).Shephard et al. (1980) reported that boys spent 20 more minutes per day in vigorous

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activity than did girls. Aaron et al. (1993) found that males reported 22.5 hours perweek of leisure time physical activity compared to 6.6 hours for females.

Recent research focusing on the gender differences in physical activity andsports participation in children has shifted from a focus on biological to social andpsychological factors (Fox et al., 1994; Vlachopoulos and Biddle, 1997). Previousinvestigations involving young children have identified parental support, enjoymentof physical activity, and time spent outdoors as factors associated with physicalactivity participation (Sallis et al., 1993).

Recent theories in developmental psychology have emphasised the importanceof the environment in facilitating and/or limiting behaviour (Morris, 1988) andincreased attention has been focused on the environmental correlates of physicalactivity (Sallis et al., 1992). However, little is known about the differences inphysical activity levels between children living in different locations (Baranowskiet al., 1993). The results of the current investigation showed that rural children weremore active than urban schoolchildren. Possible explanations for these differencesinclude the different socioeconomic conditions of rural and urban families(relatively high unemployment of rural families in Estonia), physical environments(distance of schools from homes), and possibly the different attitudes of rural andurban children towards physical activity. There are many opportunities for childrenfrom urban families of a higher socioeconomic status to develop sedentarylifestyles. For example, Robinson et al. (1993) found that the time children spendwatching TV or playing video games has increased dramatically in recent years. Inthe absence of computers in most Estonian rural families and even at local schools,rural schoolchildren have little opportunity to spend their free time playing videogames. Therefore, it can be assumed that they have more free time for outdooractivities including participation in games and exercises. Previous studies havefound that the single strongest correlate of physical activity in young children istime spent outdoors (Klesges et al., 1990; Sallis et al., 1993).

Another explanation for the higher levels of physical activity of rural school-children compared with urban children may stem from ecological models (Stokols,1992;. Sallis et al., 1997). Ecological models acknowledge that behaviour (e.g.physical activity) can be influenced by multiple intrapersonal, environmental andsocial variables (McLeroy et al., 1988). Physical environments are the least studiedpotential determinants of physical activity (Dishman and Sallis, 1994); however, itis important to understand their possible effects, because environmental characteristicsmay influence large populations (Sallis et al., 1997). Therefore, physical environmentshave the capacity to. facilitate or hinder physical activity (Sallis and Owen, 1997). Itcould be assumed that for rural schoolchildren, physical environments are richer inresources relevant for physical activity (eg. parks, playgrounds, sidewalks). On theother hand, urban schoolchildren often lack relevant conditions for participation inleisure-time physical activities which may be one reason for their lower activitylevels. Therefore, additional studies with young children are needed to identifywhich psychosocial and environmental factors affect children's physical activitybehaviour (Baranowski et al., 1993; Sallis et al., 1997).

CONCLUSION

According to the moderate to vigorous physical activity standard, the physicalactivity levels of the Estonian primary school children in this study were relativelyhigh. The 54.2 to 99.4 minutes (third-grade girls and first-grade boys, respectively)

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of daily moderate to vigorous physical activity reported by the children's parentsmet or exceeded the guidelines for physical activity proposed by the recent PhysicalActivity Guidelines for Adolescents. In addition, rural schoolchildren engaged insignificantly more MVPA than the urban schoolchildren and boys were more activethan girls of the same age.

CORRESPONDENCE

Please address correspondence to Lennart Raudsepp, Institute of Sport Pedagogy,University of Tartu, 18 ülikooli Street, Tartu, 51014, Estonia. E-mail: lennart@ut.ee

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