The European Journal of Public Health Advance Access originally published online on June 16, 2007
The European Journal of Public Health 2008 18(1):25-30; doi:10.1093/eurpub/ckm049
Your Health |
Associations between sport participation, demographic and socio-cultural factors in Portuguese children and adolescents
André F. Seabra1, Denisa M. Mendonça2, Martine A. Thomis3, Tim J. Peters4 and José A. Maia1
1 Faculty of Sports, University of Porto. Porto, Portugal.
2 Institute of Biomedical Sciences Abel Salazar, ICBAS, University of Porto. Porto, Portugal.
3 Faculty of Sport Sciences and Physical Education, Department of Biomedical Kinesiology, Katholieke Universiteit Leuven. Leuven, Belgium.
4 Department of Community Based Medicine, University of Bristol. Bristol, UK.
Correspondence: André Filipe Teixeira e Seabra, Laboratório de Cineantropometria, Faculdade de Desporto - Universidade do Porto, Rua Dr. Plácido Costa, 91, 4200-450 Porto, Portugal. tel: 00351225074789; fax: 00351225500689; e-mail: aseabra{at}fcdef.up.pt
Received January 12, 2007, accepted April 18, 2007
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Abstract |
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Background: The number of studies that focus on factors influencing the sport participation (SP) of children and adolescents is limited. The present study examines the associations between demographic [age, gender and socio-economic status (SES)] and socio-cultural factors (SP of family, and peers and physical educator influences) and the SP of children and adolescents. Methods: A random sample of 3352 Portuguese children/adolescents, 10–18 years, their parents and siblings was surveyed. The assessment of SP was based on a psychometrically established questionnaire. Multivariable logistic regression was used in data analysis. Results: (i) age was not related to children/adolescent's SP; (ii) children/adolescents with high SES (OR:1.7, 95%CI:1.4–2.2) and medium SES (OR:1.4, 95%CI:1.1–1.7) were more involved in sports; (iii) children/adolescents were more likely to participate in sports when their family also participate; (iv) boys were more likely to participate in sports than girls (adjusted OR:3.3, 95%CI:2.8–3.9 from a main effects model), but mother's SP influenced their daughters and sons differently. Daughters showed a greater propensity for practising sports when their mothers did (OR:2.5; 95%CI:1.7–3.6). For sons, sports involvement was similar whether or not their mothers participated (OR:1.1; 95%CI:0.7–1.7); (v) peers had a positive influence on the participants’ SP (OR:2.2, 95%CI:1.9–2.7); (vi) after adjusting for other factors, the influence of a physical education teacher was not found to affect the SP of the children/adolescents. Conclusion: There are important demographic and socio-cultural influences on the SP of children/adolescents—in particular, gender, SES, family members’ SP and peer influence.
Keywords: adolescents, children, demographic, socio-cultural, sport participation
The technology of modern society has dramatically changed contemporary lifestyles in favour of inactivity, sedentary life and obesity. According to the WHO,1 60–85% of people in the world—from both developed and developing countries—lead a sedentary lifestyle, making it both common and very widespread. It is estimated that nearly two-thirds of children are also insufficiently active, with serious implications for their future health.1
The importance of adhering to a healthy lifestyle in which physical activity is a major component is highly favoured by international medical organizations. The importance of physical activity is well documented in promoting longevity,2 reducing cardiovascular diseases3 and lowering risk factors associated with obesity and emotional stress.4,5 However, most of this information comes from studies using an adult population.
Given these results, it seems evident that the promotion and the implementation of physical activity programmes are of crucial relevance in terms of public health. However, to create and develop effective programmes to encourage physical activity in children and adolescents, it is necessary to identify and classify the factors that make them effective.6,7 According to Sallis and Owen,8 physical activity participation is complex, influenced by multiple factors: demographic, biological, psychological, cognitive-emotional, behavioural attributes and skills, socio-cultural and physical environment. In this study, we will focus our attention on selected demographic and socio-cultural factors.
In respect of demographic factors, age, gender and socio-economic status (SES) are those most frequently studied. According to Sallis et al.,7 the most consistent findings are that boys are more active than girls, and younger children are more active than older youth. SES is thought to be associated with children's and adolescents’ physical activity levels, but the existing literature does not agree on the extent and direction of this relationship.9–11
Regarding socio-cultural factors, several authors indicate that the social influences on physical activity in children and adolescents include parents, siblings, peers and physical education teachers.7,8,12 Several studies have investigated those influences on physical activity habits, but the results are so varied that they prevent drawing sufficiently clear conclusions about the extent and the direction of these relations.13–19
Caspersen et al.20 suggest a broad definition of physical activity as ‘any body movement produced by skeletal muscles that results in energy expenditure’. This definition has been mainly used in US and European traditional research in the epidemiology of physical activity. This type of research did not typically consider one of the major physical activity phenotypes, namely sports participation (SP), with its variations in level, frequency and duration associated with training and competition at all levels. SP takes place in leisure and organized sports and in physical education classes. It is generally accepted that physical education classes are sport education.21
There is clear evidence from cross-sectional and longitudinal studies that relatively high levels of activity produce health benefits in terms of adiposity, some lipid measurements, musculoskeletal and cardiovascular health.22 Specifically, there is evidence that to induce and maintain such beneficial effects requires sustained amounts of moderate or vigorous physical activity, apart perhaps from benefits in terms of weight loss where the benefits are more gradated. Clearly it is in principle possible to attain such high levels through activities not linked with participation in sports, but in practice spontaneous and leisure time activities seldom meet the intensity, frequency and duration of energy expenditure as is evident in sport participation. Sallis and Owen8 reported that although 
80% of US adolescents meet the general guidelines for daily physical activity, only about two-thirds of boys and one-half of girls meet the guidelines for regular vigorous activity. A similar trend is seen in some European countries as reported by Riddoch et al.23 based on data from the European Youth Heart Study, where adolescents do not meet the recommended guidelines for physical activity.
Despite these trends, sports practice (that is, a regular and systematic training schedule as well as an organized competition system) is widespread all over Portugal, especially in children and adolescents. The socio-cultural impact of sports practice and its related psycho-physiological benefits are believed to be responsible for a 24.3% increase in the number of participants (from 116 759 to 145 148) between 1998 and 2004.24
In order to fill the gap in epidemiological information, we designed a study to determine the associations between selected demographic (age, gender and SES) and socio-cultural (the SP of parents, siblings, peers and physical education teachers) factors and the SP of children and adolescents.
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Methods |
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Participants
A random sample of 3352 Portuguese boys and girls from 10 to 18 years of age, along with their parents and siblings, was surveyed during 2003–05 between March and June so as to avoid additional effects of seasonal variation. Children and adolescents were in the second and third cycles of basic education and secondary school in different regions of Portugal. In each region, a random and representative sample from the fifth to twelth grades was chosen, within the event 140 classes being surveyed from 30 schools. The project was approved by the research committee of the Faculty of Sport of the University of Porto and school authorities. Parents and children provided informed consent.
Sport participation
SP of children and adolescents, their parents, and siblings was estimated using the Baecke et al.25 protocol. This is a reliable and valid instrument to measure different facets of physical activity.26,27 It has been used previously with the Portuguese population 10–18 years of age with reliable results.28
The Baecke questionnaire has been translated and culturally adapted to the Portuguese population. It comprises 16 Likert-type items designed to map different aspects of physical activity. For this study, one indicator of SP was used, a binary variable regarding yes/no participation in sports; which was the response to question 9: ‘Do you play sport? – yes/no’. SP was defined as all practice and performance of formal sports in private clubs and schools. School sports in Portugal are voluntary programmes offered during free/discretionary time and have defined competitive seasons. Information on formal physical education activities was not utilized.
With the purpose of assessing the influence of peers and physical education teachers on the SP of children and adolescents, two more questions were added to the Baecke et al. questionnaire: ‘Did your friends influence your SP? – yes/no’; and ‘Did your physical education teacher influence your SP? – yes/no’.
Given that a number of the parents in this study were not economically active, SES was assessed by the occupation of the head of household. Head of household was defined in terms of who had the dominant occupational position (mother or father) as suggested by Kunst et al.29 This indicator of SES was coded from questions asking parents about their jobs. The occupation was categorized into three levels: high (professionals), medium (intermediate skilled workers) and low (semi-skilled and unskilled manual workers).
Following training, teachers at each of the selected schools administered the questionnaires in the school. Teachers worked with the participants to ensure complete and accurate responses.
Statistical procedures
Descriptive statistics were used to provide information about different aspects of the sample. Multivariable logistic regression models were used to study the influence of the following factors: age (continuous variable), gender, SES, parents’ and siblings’ SP, and the influence of peers and physical education teachers on the SP of children and adolescents. Odds ratios (OR) and their 95% confidence intervals (CI) for each factor were adjusted for all the other factors in the model. The relationship for the continuous variable age was assessed for non-linearity using fractional polynomial analysis. SPSS 14.0 and Stata 9.0 were used for all analyses.
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Results |
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Characteristics of children and adolescents are detailed in Table 1. Fifty eight percent of the participants were involved in sports. The sample included slightly more girls than boys, and nearly half were in the lower SES group. About a fifth of parents and half of the siblings reported participating in sports. About 40% of children and adolescents identified themselves as being influenced by peers and physical education teachers.
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Table 2 shows the prevalence of SP among children and adolescents for all the variables studied.
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The prevalence of SP was higher in males (72%) than females (45%). A higher proportion of SP was found in children and adolescents with high (71%) and medium (59%) compared with low (50%) SES. More than 70% of boys and girls participated in sports when their parents (mother – 79%; father – 73%) and siblings (72%) also participated. Higher SP was found in children and adolescents who were influenced by peers (73%) and physical education teachers (63%).
After adjustment, the variables that remained associated with the children and adolescent's SP were: SES, gender, family SP and peer influence. High and medium SES children and adolescents were more likely to be involved in sports than those of low SES. No difference in SP prevalence was detected when comparing medium and high SES (OR: 0.8; 95%CI: 0.6–1.0).
Family (mother, father, siblings) SP had a positive influence on the SP of children and adolescents. When the family took part in sports activities, boys and girls were much more likely to participate in sports than when the family did not (ORmother: 1.8; 95%CI: 1.3–2.4; ORfather: 1.7; 95%CI: 1.3–2.1; ORsiblings: 3.1; 95%CI: 2.6–3.6).
Boys were more likely to participate in sports than girls but there was a marked interaction between the mother's SP and the gender of the offspring, showing the different influences of mother's SP on their daughters and sons (interaction OR: 0.4; 95%CI: 0.3–0.8; P = 0.004). The adjusted OR for mother's SP amongst girls (OR: 2.5; 95%CI: 1.7–3.6) showed that daughters were much more likely to be involved in sports when their mothers also participated compared with daughters whose mothers did not. For sons, sports involvement was similar whether or not their mothers participated (OR: 1.1; 95%CI: 0.7–1.7). Put another way, when the mothers were not involved in sports, sons were more likely to participate in sports than daughters (OR: 3.6; 95%CI: 3.0–4.3). When the mothers were involved in sports, the likelihood to participate in sports was similar in sons and daughters (OR: 1.6; 95%CI: 0.9–2.7). No such interaction between the father's SP and the gender of the offspring was found (P = 0.29).
While peers had a positive influence on the SP of children and adolescents, when added to the main effects model presented in Table 2 neither age (adjusted OR: 0.97; 95%CI: 0.9–1.0; P = 0.15) nor physical education teacher's influence (OR: 1.09; 95%CI: 0.91–1.31; P = 0.35) were associated with the SP of children and adolescents. Peer influence was the factor essentially responsible for the attenuation of the teacher's influence.
The inclusion of non-linear terms for age in the models revealed no improvement over linear term, and the inclusion of the interaction between mother's SP and the child's gender had negligible effects on the main effects of the other factors in table 2.
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Discussion |
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This study attempted to determine the associations between selected demographic and socio-cultural factors and the SP of children and adolescents.
Interestingly, children's and adolescents’ ages were not associated with their SP. This result contradicts some reports where a declining trend in physical activity and SP is shown, although none of the published research is associated with a southern or Mediterranean part of Europe.14,17,30,31 In Portugal, there are many reasons for our finding, such as the high social and cultural relevance of sport participation to Portuguese children and adolescents. Another is the increased number of youth participants in systematic training and organized sports.
According to Adelino et al.,24 the number of participants in formal sports increased by 24.3% (116 759 to 145 148) from 1998 to 2004. Over the same period the number of males participating in formal sport increased by 19.5% (from 91 874 to 109 790), while the number of girls increased by 42.1% (from 24 885 to 35 358). Moreover, it is important to note that in 1998 the prevalence of youngsters practising sport was 13.5% and in 2004 was 18.4%. A third possible explanation is an increase in the number and variety of sports activities provided by the school sports clubs. Nowadays Portuguese children and adolescents have greater and better opportunities to join and participate in sports during free time, decreasing the time in sedentary activities.
In this study, the results have shown the importance of medium and high SES to SP. The existing data were not clear about the extent and direction of the association between SES and SP in children and adolescents. However, several authors have shown that higher SES is positively associated with SP.10,14,16,17,32,33 Given that children and adolescents spend a great part of their daily time at school, they commonly need to develop SP after school time. However, they require social and economic support to access such activities, which usually take place in sports facilities (clubs, swimming pools, gyms) and involve travelling, buying the necessary equipment and paying for the subscription fees.
It is generally accepted that socio-cultural support, namely family, peers and physical education teachers’ influence, is important and critical for child and adolescent development, interest and involvement in sports activities, as a part of an active and healthy lifestyle.
We have shown a positive impact of parental SP in their children's SP. This same trend has been put forth by other research showing that physically active parents tend to have relatively active children.13–19 Different explanations have been suggested for this observation. According to Schor,34 family members tend to resemble one another in terms of health status and health behaviours. These similarities reflect familial, genetic predispositions; shared physical, social and emotional involvements, and also learned health beliefs and values. Taylor et al.,35 suggested that parents can promote or restrict SP of their offspring directly and indirectly. On one hand, they can limit access to facilities, equipment and SP involvement but, on the other hand may serve as participation models for those activities.
We found a differential association between mother's and offspring's SP according to the child's gender—that is, there was an interaction between the mother's SP and her offspring's gender that reflected a stronger influence of mothers on their daughters’ SP than on their sons’ SP. Specifically, female offspring showed a greater propensity for practising sports when their mothers did compared with when their mother did not, whereas the participation of male offspring was not influenced by the mother's participation. There was no evidence of an interaction between father's SP and the offspring's gender. While speculative given the current evidence, if this lack of a differential effect is genuine then it could reflect the notion that the father's role in Portugal is both relatively dominant in terms of influence on physical activity levels but also that there is no reason that this influence should favour a particular gender among offspring.
Available evidence shows a specific socialization according to parental gender.13,14 Some show an association in the levels of SP between mothers and daughters, and between fathers and sons. Wold and Andersen13 concluded that mothers had a strong influence in their daughter's sports involvement and fathers had a stronger influence upon their sons. O'Loughlin et al.14 have also found parental influence in SP with more significance in the association between fathers and sons, and between mothers and daughters.
In this study, it is also important to note that when mothers were not involved in sports activities, boys were approximately three times more likely to participate than girls. Previous research showed that boys are more active than girls.14,16,17,30,31,33,36 The main explanation put forward by several authors regarding this larger sport involvement by males is one of a socio-cultural nature.37,38 In the recent past, the social and cultural role appointed to males was based upon working or strenuous activities, whereas the female's was focused on family life activities. Furthermore, since early childhood, males have been encouraged and rewarded for taking part in SP whereas females have been encouraged to get involved in sedentary activities, especially of a domestic or housekeeping nature.39,40 Other explanations for this lower involvement of girls in sports compared to boys are the differences in body image, physical abilities and attitudes necessary for the practice of sports activities.41
In addition to parents, siblings’ SP seems also to exert a positive and independent influence upon the habits of SP. Although the research is limited, similar results have been found previously.13,15,17
Regarding peer influence, it is widely accepted that children and adolescents tend to develop group activities with their friends. This study confirmed the positive association between peer influence and the SP of children and adolescents. It has been suggested that physically active children tend to have equally active friends.13,15,17,19 According to Duncan et al.,19 the social support of peers for the practice of SP in children and adolescents can be seen in social integration (when they participate together in the activity), in emotional (encouragement) and instrumental aspects (sharing equipment and means of transportation).
In our study, physical education teacher was a positive influence on the SP of children and adolescents in the univariable analysis. However, after adjusting for peer influence, physical education teacher's influence was attenuated. This result is somewhat surprising because it was expected that the influence of physical education teacher would be maintained, notwithstanding a possible pathway through peers in the establishment of active behaviours and lifestyles. In the available literature, there are studies that investigate the extent and direction of the physical education teacher association upon the SP of children and adolescents.17,42,43 As there are very different results, it is not possible to draw clear conclusions, but several authors recognize the social association of physical education professionals in being most effective in preventing inactivity.
Any interpretation of our study findings should bear in mind certain methodological limitations. First, cross-sectional designs preclude the establishment of causation and suffer from cohort effects. Nevertheless, such designs are perhaps the most frequently conducted type of study to collect information from large samples in a relatively short period of time and are frequently reported in the literature about epidemiology of physical activity.44 Second, the methodology of using questionnaires to measure the SP means that data were self-reported. This might lead to potential biases that cannot be controlled for—for instance, whether the respondents answered the questions in what they perceived as a socially desirable manner. However, questionnaires are currently the most widely used method for the assessment of SP in epidemiological research with large sample sizes such as the present one.45 Third, there are potentially clustering effects resulting from school and class influences, which unfortunately cannot be adjusted for the given data available. With an average of about 24 respondents per class and 112 per school, these effects would be expected to increase the P-values and widen the confidence intervals in table 2. However, the magnitudes of the odds ratios and the high levels of statistical significance mean that such effects are very unlikely to entirely explain the findings. For example, the levels of clustering (intra-cluster correlation coefficients, ICCs) that would need to pertain before the significance of the adjusted OR for peer influence which would be removed is about 0.2 by school and 0.8 by class. The latter is clearly implausible and the former is fairly large; hence the findings are reasonably robust to such clustering effects.
In summary, it is important to emphasize the implications of this research in terms of its potential in establishing and developing varied programmes of SP. We would like to point out a need to develop programmes that would: (i) specially focus on girls, who face a higher risk of inactivity; (ii) offer more equal access to such programmes and not demand the existence of specialized people, sports material, equipment or financial support; (iii) recognize that the construction of a healthy lifestyle is not an individual project but the outcome of a network of interpersonal relations that include family members and peers.
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Acknowledgement |
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This study was supported by the Portuguese Foundation of Science and Technology (SFRH/BD/20166/2004). We thank Mrs Nina Laidlaw from the Pennington Biomedical Research Center for her editorial contribution to this manuscript.
Conflicts of interest: None declared.
Key points
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