|  | Feature: Physical Education in Early Childhood | No.51 September 2007 |

Physical Activity and the Effect of a Movement Program on the Energy Expenditure of Preschool Children Anita E. Pienaar, Christal Stadler & Ankia Oosthuizen |
Abstract A decline in physical activity (PA) among children is a worldwide concern. It is also of concern among preschool children. This study aimed at determining the activity profiles of preschool children and if energy expenditure (EE) and PA would increase after participation in a movement program. Three to six-year-old children (N=16, 11 boys, 5 girls) with a mean age of 4.1years form part of the study. PA was monitored over three consecutive days and the group participated in the movement program on day two of three days. Total energy expenditure (TEE) was monitored using the Actical® accelerometer over the three day period (12.9 hours per day), while parents and teachers completed activity diaries for the same period. A SAS analysis of the highest percentage of activity occurrences and the EE of these activities, revealed high PA levels and that outdoor play contributed to the highest percentage of daily activities. A repeated measures ANOVA indicated tendencies of higher TEE and percentages of activities in the vigorous zone (p>0.05) on the day after participating in the movement program. It was concluded that different factors such as the parents, the preschool program and the environment influenced the physical activity levels. A structured movement program also seemed to have an overflow effect on PA levels and EE, especially on activities of a vigorous nature. Key words: Energy expenditure, movement program, physical activity, motor performance, preschool Introduction Physical Education was omitted from the South African school curriculum a few years ago, carrying the message that this is not an important part of a child’s holistic development. In addition, grade R learners (5-6 years) are more and more phased into formal school education, contributing to a tendency towards less time being allocated to physical activity. A similar tendency is subsequently seen in preschools where more time is spend in formal education in an effort to get the child ready for formal schooling. Such decisions impede on the unique, diverse and comprehensive developmental needs of young children. Garcia, Floyd and Lawson (2002), indicate that early childhood is a unique period of a child’s life, as this is a time in which they develop physically, emotionally, intellectually and socially. Physical activity, movement experiences and exposure to structured movement development programs during this period are therefore imperative in assisting them to develop fundamental and perceptual motor skills and confidence. It is also a critical part of a young child’s school readiness make up as it is linked to positive cognitive outcomes, while also associated with health consequences (Coe, Pivarnik, Womeck, Reeves & Malina, 2006). Thus, preschools who value physical activity as important are therefore forced to allow people who offer different kinds of activity programmes to fill this need during school hours. Sääkslahti, Numminen, Rask-Nissilä, Viikari, Tuominen and Välimäki (1999) indicate a relationship between physical activity patterns during weekends and fundamental motor skills of three to four-year-old children. Pienaar and Badenhorst (2001) report higher physical activity levels (PAL) and a broader gross motor activity profile during participation in a structured movement program than during free play at a pre-primary school among five-year-old children. In addition, Dale et al. (2000) indicate higher PAL after participation in a structured movement program than on days when no participation took place among grade three and four learners. A study of 10-year-old school children also revealed more activity during the day among boys who walked to school compared to those who made use of vehicle transport (Cooper, Page, Foster & Qahwaji, 2003), while similar results are reported in a more resent study by Cooper, Andersen, Wedderkopp, Page and Froberg (2005). It thus seems that participation in structured physical activity programmes and being physically active have a positive effect on the PAL and motor development of young children. The National Association for Sport and Physical Education (NASPE, 2002) recommends that preschool children should participate in physical activity for at least 120 minutes accumulated per day. They further recommend that half of this time must be spent in structured play while the other half must consist of free play. Research is, however, revealing that the PAL of young children decreases progressively (Whitney & Rolfes, 2002; Pate, Pfeiffer, Trost, Ziegler & Dowda, 2004; Reilly, Jackson, Montgomery, Kelly, Slater, Grant & Paton, 2004; Montgomery, Reilly, Jackson, Kelly, Slater, Paton & Grant, 2004). Although research has established that modern children show progressively decreased levels of physical activity, limited research findings exist regarding the physical activity levels and activity profiles of preschool children. In addition, no studies could be traced on the post-exercise effect of activity on the activity levels of preschool children. The first aim of this study was to determine the activity profiles and the intensity level of activity of three to six-year-old children and secondly, to assess whether physical activity levels will increase after participation in a structured movement development program. Methods Participants Sixteen children between the ages of three and six years (M of age = 4.1 years, range 3.6 years to 6.1 years), including 5 girls (M of age = 4.2 years) and 11 boys (M of age =4.5 years) participated in the study. The socio-economic status of the group can be considered as medium to high. A purposive sampling technique was used to sample participants. All the participants had to be enrolled in a structured movement development program (kinderkinetics program) conducted at the motor clinic at the University or at a preprimary school. Data collection The study was conducted over three consecutive days of the week. The first day served as the control day (Day 1), as the children participated in the Kinderkinetics program on the second day (Day 2), while the third day (Day 3) was considered as the day following the structured program. Energy expenditure (EE) and physical activity levels (PAL) were determined by means of the Actical® accelerometer. This is a small, water resistant device (28mm x 27mm x 10mm and weighing 17.5g), with a large storing capacity which is positioned on the right hip of a person by means of an elastic band. The frequency, intensity and time spent on physical activity in one plane are measured by the Actical®. It is an accurate indicator of energy expenditure during unrestricted activities (Pfeiffer et al., 2006; Welk et al., 2004), and Actical® readings are associated with VO2 of three to five-year-old children when they perform structured weight-bearing activities. The cut-off points for the different intensity levels of the Actical® are 0.01 kcal/min/kg for light to moderate intensities and 0.05 kcal/min/kg for moderate to vigorous intensities. The Actical® was positioned by the researchers on the child at 07:00 every morning and removed at 20:00 every evening (which was considered the ‘waking hours’ of the children) for three consecutive weekdays, after which the data was stored on the Actical® software, and analyzed by means of the Actical® software edition 2.0 (Mini Mitter Company, Inc., 2003). The activity profiles were recorded by means of daily activity dairies, completed by teachers and parents. They were briefed by the researchers on how to complete the activity diary, after which the teachers completed an activity diary based on a broad description of activities for each child during preschool time and the parents during home time. The activity diary was divided into half-hour intervals from 07:00 until 20:00, and main activities done during this period were recorded. The intensities of all activities were consecutively recorded by the Actical®. An activity diary divided into one-minute intervals was also completed by the researchers to describe the activities preformed during the structured part of the Kinderkinetics program on Day 2. The SAS computer program was used to compile an activity profile from the activity diaries for each day, which was arranged in mean half hours of occurrence (SAS, 1999). A repeated measure ANOVA with a Bonferonni adaptation was conducted by means of Statistica (2006) to determine differences between the days with regard to the time spent in different activity intensities and EE of the activities. The sixty minute program (consisting of 30 minutes of developmentally appropriate movement activities called a Kinderkinetics program and 30 minutes of free play) was conducted at the perceptual-motor clinic of the University and also at a preschool during school hours by trained Kinderkineticists (post graduate students in Human Movement Science, specialising in the field of motor development of children). The structured part of the program includes activities such as fundamental skills (e.g. running, galloping, body awareness activities (e.g. touching different body parts), static- and dynamic balancing activities (e.g. standing or jumping on one leg), total body, hand-eye and foot-eye coordination activities (e.g. throwing and catching a ball), spatial orientation activities (e.g. climbing through a tunnel), rhythm and timing activities (e.g. marching to music, fine motor skills (e.g. playing pick-up sticks), perceptual skills (e.g. form identification) and activities which improve muscle tone such as standing long jump. Enrolment in this program was compulsory and paid for. Results Table 1 indicates the specific categories of activities included in the Kinderkinetics program of 30 minutes, and the times spend on each of these categories. Most of the time was spent doing fundamental movement skills, hand-eye coordination and activities to improve spatial orientation. Sedentary activity (waiting for a turn, resting between activities, fine motor activities) took up 19% of the total time of the program. Table 1 Categories of Activities and Percentage Time Spend Performing the Activities during the structured part of the Kinderkinetics Program The group wore the accelerometers for an average of 12.9 waking hours per day over the three days. Table 2 displays the results of the activity profiles compiled by the teachers and parents for each day, which was arranged in mean half hours of highest percentage occurrence. Total energy expenditure (TEE) of the activities is also expressed per half an hour in order to analyse the energy expenditure (EE) of the different activities. Outdoor play contributed to the largest percentage of time of the activity profile which varied between 12.73% and 15.05% (1.38 hours to 1.56 hours) over the three days. The average EE during outdoor play (26.91 Kcal/half an hour) was also the highest of all the activities recorded for each day. Other activities with high EE levels that were recorded over the 3 days, but in much smaller percentages, were indoor play, playing at friends’ and household chores. Participation in other activities which contributed to relatively high EE such as free play, bicycling, climbing activities, doing animal movements, attending parties, activity and rugby lessons, did not occur on each of the days and also contributed to only small percentages of the daily activities of the children. Table 2 Activity Preferences (% time and Energy Expenditure) on Days 1-3 Total EE= Energy expenditure in Kcal/half-hour Note –only activities contributing to more than 1% of the time are included in the table. No information= parents forgot to complete the diary/put the accelerometer back on the child The participation in the Kinderkinetics program on Day 2 contributed to the highest EE of all the activities (30.50 Kcal/half-hour), except for playing rugby on Day 1. Watching television took up between 6.70% and 8.13% (between 51 minutes and 1.02 hours per day) of each day and contributed to the lowest EE of all the activities (EE= 13.00 Kcal/half-hour). A slight change was evident in the activity profile on Day 3. Participation in outdoor play increased from 13% to 15% and the percentage time spent watching television decreased compared to Days 1 and 2. The group also spent time imitating animal movements, which was not reported during Days 1 and 2, but which were part of the Kinderkinetics program. Table 3 displays the different activity intensity zones, the total hours spent in these activity zones and the EE over the three days, as analyzed by the Actical® software, for an average of 12.9 hours. It happened that children woke up later than 7:00 or went to sleep earlier than 20:00 when the Actical was removed, therefore less then 13 hours are recorded. The results indicate that the group were quite active over the three days. They spend an average time of 2.31 hours doing vigorous intensity activities, and 4.11 hours doing moderate intensity activities, totalling 6.42 hours from a total of 12.9 hours doing activities of a moderate and vigorous nature (MVPA) per day. The percentage time spent in each of the activity zones are also indicated in the column for the Kinderkinetics program. Approximately 75% of the program included activities of a moderate and vigorous nature. Table 3 Activity Intensity, Total Hours Spent and Energy Expenditure over the Three Days KK= kinderkinetics program (sixty minutes, structured and free play) A repeated measures ANOVA with a Bonferonni adaptation was conducted to establish possible differences between the 3 days with regard to the intensity of the activities and the TEE and the results are presented in Table 4. Table 4 Significance of Differences in Energy Expenditure and Time Spent doing Different Intensity Activities df =degrees of freedom The percentage time doing activities with a vigorous intensity increased from 17.9% to 22.7% (2.12 – 2.43 hours) and TEE increased from 173.6 to 228.9 Kcal from the first to the third day, although not significantly. Higher percentages of vigorous activity are indicated on Day 2 and 3 compared to Day 1 with the highest percentage on Day 3. Taking into consideration that the Kinderkinetics program contributed to a substantial percentage of activities with a vigorous nature (40.9%) and TEE of 59.5 kcal of the program time on Day 2, the percentage of activities of a vigorous nature was still higher on Day 3. However, these changes in percentage of vigorous activity and TEE while being vigorous were not significant on Day 3 (p>0.05, Table 4). The highest percentage of time was spend on moderate intensity activities, although it progressively decreased from Day 1 to Day 3 (4.34 – 3.56 hours) and the decrease from Day 2 to Day 3 was significant (p<0.05). The higher percentage of time in the vigorous zone on Day 3 might have contributed to this. Participation in light intensity activities ranged between 2.58 and 3.31 hours, while time spent doing sedentary activities took up the smallest percentage of time. None of these percentages differed significantly on the different days. Discussion The activity profiles and TEE of this group of preschool children indicated that they were highly active over the three day period. They easily met the requirements of the NASPE (2002) guidelines for preschool children, seeing that time spent doing MVPA ranged between 5.99 and 6.40 hours over the three day period. It thus seems that they are sufficiently physically active and that the parents, the preschool and the circumstances in which they grow up might be important role players in their activity profiles. The inclusion criteria which required participation in a Kinderkinetics program could also have influenced the results. It seemed that the parents were aware of the developmental and health benefits associated with physical activity by enrolling their children into a Kinderkinetics program which was compulsory. The role of the program followed at the preschool and the activities offered there was also vital in fostering an active activity profile. Research by Pate et al. (2004) indicates, in this regard, that preschool policies and practices have an important influence on the overall activity levels of the children they serve. The results of this study are therefore contradictory to the studies of Reilly et al. (2004) and Montgomery et al. (2004), who found very small percentages of MVPA in their groups of Scottish preschool children, and agree to a certain extent with the perceptions among parents and health professionals that young children are spontaneously active (Reilly et al., 2004). The inclusion criteria of our study, and the fact that overweight and obese children form a big part of their study groups, made direct comparison between the studies difficult. Pate et al. (2004) indicate that the American preschool children in their study spent 1 hour in 8 hours in the vigorous activity zone while attending preschools. Although their study was only focussed on the time attending a preschool, activity spend doing vigorous activities compared reasonable with the average of 2.30 hours that our group was vigorous, although over a 12 hour period and which included preschool and home time. In comparison to the reported waking hours in the above studies, our children were also monitored over a longer waking period per day, from which it can be derived that they may have longer waking hours, and thus have more time to be active. Our study also included fewer girls than boys and they were also slightly younger than the boys. Findings reported on gender differences in PA among preschool children indicate that boys are more active than girls and also that older boys are more active than younger ones (Reilly et al., 2004; Montgomery et al., 2004). This might have contributed to the high percentage of moderate and vigorous activity found in our group. Recorded activities such as rugby and playing with toy cars are normally considered boyish activities and also contributed to from the highest energy expenditures reported in our study. The activity profile of the group shows that outdoor play took up the largest percentage of their time and that such activities contributed to high EE. This is in agreement with the conclusion of Pate et al. (2004) that the time children are allowed to play freely in settings that are conducive to physical activity such as outdoor playgrounds, exerts a strong influence on physical activity. They report the findings of Mackenzie which indicated that children engaged in MVPA for 40% of the time they spend in outdoor recess, compared to the 13% in their study observed for the entire school day. The high TEE during the Kinderkinetics program further highlighted the importance of such structured activity programs in improving the activity levels of young children, especially in environments which are not conducive to physical activity. It is also evident from the compiled activity profiles that a big percentage of the children’s time was taken up by activities out of their control, such as travelling with their parents and meal times (which took up the second and third highest percentages of their time), and helping their caregiver’s with house chores. On Day 3 the percentage time spent travelling was much less compared to on the other days, while the percentage time playing indoors increased substantially, again indicating how the program of the caregiver might have influenced the child’s activities. From this it can be concluded that the program of the primary caregiver has an important influence on the activities of young children, as they are in need of constant supervision, therefore the child’s activities are arranged around the activities of the caregiver. In addition, the parent is also the one who decides on the extra activities the child can engage in such as rugby, swimming and Kinderkinetics lessons, which adds to the activity profiles of this group. Watching television contributed to the lowest EE during the different days but took up only an hour a day. This rather limited time spent watching TV might also be under the control of the parent. It can be concluded from these activity profiles that the parents might acknowledge the importance of motor development programs and are aware of the health benefits of an active lifestyle for their children. The second aim was to determine if participation in the Kinderkinetics program would increase PAL after participation in the program. The EE and the percentage time spent on physical activities with a vigorous intensity were the highest on Day 3, although this increase was not significant. It must, however, be taken into account that the PAL were already high to begin with, and to show a further significant increase might have been difficult to achieve. However, the higher percentage of vigorous activities seen on Day 3 might have been influenced by the Kinderkinetics program they participated in on Day 2, as 40.9% of this program was based on activities with a vigorous intensity, therefore making a substantial contribution to the TEE on Day 2, in comparison to Day 1 where only 17% of the time were spend doing vigorous activity. The results are thus in agreement with researchers (Cooper et al., 2003; Cooper et al., 2005; Dale et al., 2000), who indicated that high PA levels may foster high PAL later. It can thus be concluded that this group of preschool children were sufficiently active to derive health benefits, regardless of participation in the Kinderkinetics program, but that participation in this program showed tendencies of a shift towards further increases in activities of a vigorous nature. They also tend to experiment with the activities included in the program which had a positive benefit, not only on increased energy expenditure but also improved motor development. The findings should however be viewed taking the limitations of the study into account. The small sample size and specific inclusion criteria limit the generalizing of findings. Waking up and going to sleep routines were irregular, parents and teachers sometimes forgot to complete the activity diary or to put the accelerometer back on the child, contributing to inconsistent start and end measurements and incomplete activity profiles. Such problems should be addressed in future studies, while parents should also be interviewed to establish their attitudes towards health-related issues, as it was concluded that the parents’ attitude towards a healthy lifestyle might have influenced the high activity levels found in this study. In spite of these shortcomings, this study brought forth important findings in terms of the physical activity preferences and energy expenditure of activities preschool children engage in on a daily basis in a South African context. It also highlighted the factors that might influence the physical activity levels of preschool children and the possible contribution of structured movement programs in the improvement of activity profiles. More studies are recommended to further explore these findings. References Coe, D.P., Pivarnik, J.M., Womack, C.J., Reeves, M.J. & Malina, R.M. (2006). Effect of physical education and activity levels on academic achievement in children. Medicine and Science in Sport and Exercise, 38,1515-1519. Cooper, A.R., Page, A.S., Foster, L.J. & Qahwaji, D. (2003). Commuting to school: are children who walk more physically active? American Journal of Preventive Medicine, 25(4), 273-276. Cooper, A.R., Andersen, L.B., Wedderkopp, N., Page, A.S. & Froberg, K. (2005). Physical activity levels of children who walk, cycle or are driven to school. American Journal of Preventive Medicine, 29(3), 179-184. Dale, D., Corbin, C.B. & Dale, K.S. (2000). Restricting opportunities to be active during school time: Do children compensate by increasing physical activity levels after school? Research Quarterly for Exercise and Sport, 71, 240-248. Garcia, C., Garcia, L., Floyd, J. & Lawson, J. (2002). Improving public health through early childhood movement programs. JOPERD, 73(1), 27-31, January. Mini Mitter Company, Inc. (2003). Actical®. Physical activity monitoring system. Instruction manual. Software version 2.0. United States of America: Mini Mitter Company, Inc. Montgomery, C., Reilly, J.J., Jackson, D.M., Kelly, L.A., Slater, C., Paton, J.Y. & Grant, S. (2004). Relation between physical and energy expenditure in a representative sample of young children. American Journal of Clinical Nutrition, 80, 591-596. Pate, R.R., Pfeiffer, K.A., Trost, S.G., Ziegler, P. & Dowda, M. (2004). Physical activity among children attending preschools. Pediatrics, 114(5), 1258-1263. Pfeiffer, K.A., Mcifer, K.L., Dowda, M., Almeida, M.J.C.A. & Pate, R. R. (2006). Validation of calibration of the actical accelerometer in preschool children. Medicine and Science in Sports and Exercise, 38(1), 152-157. Pienaar, A.E. & Badenhorst, P. (2001). Physical activity levels and play preferences of pre-school children: recommendations for appropriate activities. Journal of Human Movement Studies, 41, 105-123. Reilly, J.J., Jackson, D.M., Montgomery, C., Kelly, L.A., Slater, C., Grant, S. & Paton, J.Y. (2004). Total energy expenditure and physical activity in young Scottish children: mixed longitudinal study. THE LANCET, 363, 211-212. Sääkslahti, A., Numminen, H.N., Rask-Nissilä, L., Viikari, J., Tuominen, J. & Välimäki, I. (1999). Is physical activity related to body size, fundamental motor skills, and CHD risk factors in early childhood? Pediatric Exercise Science, 11, 327-340. SAS. (1999). SAS system for Windows Release 8.02 TS level 02M0. Cary, NC: SAS Institute. Statsoft. (2006). Statistica for Windows. Release 5.5: general conversions and statistics. Tulsa, Oklahoma: StatSoft. Welk, G.J., Schaben, J.A. & Morrow, J.R. (2004). Reliability of accelerometry-based activity monitors: a generalizability study. Medicine and Science in Sports and Exercise, 36(9), 1637-1645. Whitney, E.N. & Rolfes, S.R. (2002). Understanding nutrition. United States of America: R.R. Donnelley/Willard. Contact Prof. Anita Pienaar School of Biokinetics, Recreation and Sport Science North-West University South Africa Email: anita.pienaar@nwu.ac.za Christal Stadler & Ankia Oosthuizen Post graduate students School of Biokinetics, Recreation and Sport Science North-West University South Africa http://www.icsspe.org/portal/index.php?w=1&z=5 Physical Activity and the Effect of a Movement Program on the Energy Expenditure of Preschool Children Anita E. Pienaar, Christal Stadler & Ankia Oosthuizen