Cross-cultural comparisons of motor competence in southern Brazilian and Portuguese schoolchildren

Abstract Aim: This study aimed to compare the MC levels of Brazilian and Portuguese schoolchildren from 4 to 11 years. Methods: One hundred and forty-eight Brazilian children were evaluated using the Motor Competence Assessment (MCA) instrument and were later compared to the existent normative values of Portuguese children for a similar age range. Results: Our findings showed that MC increased with age, and boys outperformed girls, especially in the older age group. The distribution of the Brazilian children showed that while Brazilian boys perform above Portuguese normative values in 4 of the 6 tasks of the MCA, Brazilian girls perform below those values in all tasks, except for the standing long jump. Conclusion: The differences found, especially in girls, may be related to differences in the Physical Education curricula and how school recess periods are used.


Introduction
Motor competence (MC) is understood as an underlying capacity that relates to a person's ability to perform on a broad range of motor skills, such as locomotion, stabilization, and object manipulation, that are fundamental for the acquisition of specialized movements in future life 1,2 . Its development occurs along with lifespan, with special emphasis during childhood, involving interactions between the neuromuscular system and the environment [3][4][5] . Good levels of MC contribute to enhanced learning of new skills (i.e., faster acquisition of higher performance levels) and a higher motor proficiency on novel motor tasks throughout the lifespan 6 . MC can be developed by situation-specific motor demands 7 , it has been shown to have a sex influence 6,8,9 , and it is expected to be retained in the long term. There is a current growing interest of the scientific community on the role of MC, which has been positively associated with health-related fitness, health, and developmental outcomes 10,11 . Besides, although physical fitness is related to physical activity, both are related to children's MC 2 .
Indeed, in the last few years, there has been increasing evidence of the importance of MC for developing healthy lifestyles 5,[12][13][14] and sports participation 15,16 in children. In 2008, Stodden's model 5 proposed that physical activities in early childhood would promote the development of MC, which would lead to long-term adherence to physical activity through a variety of exploratory movement experiences. The impact of MC in children's trajectories of physical activity and physical fitness in later life was confirmed by different studies 5,12,17 .
The experiences children have early in life, which influence MC, are dependent on the culture the child lives in. The multiple contexts and affordances that are presented to children, such as home, school, sports environments, or places that afford free play 18 , and the expectations that adults have regarding children's behaviors in those contexts, vary between different cultures 19,20 . The literature shows that cultural diversity should be considered when trying to understand how children develop MC across ages 17,21 . A wide range of studies has compared different motor components in children around the world [22][23][24] , and there is a growing body of research trying to compare children in different countries and regions 17,21,[25][26][27] . Bardid and colleagues 17 evaluated the MC of Australian and Belgium children between 6 and 8 years of age showing that Belgium children outperform Australians on jumping sideways, moving sideways, and hopping for height. Besides, Australian children scored below average on the general MC test. The authors considered that cultural differences in physical activity, physical education (PE), and active transport could help to explain the results. Luz et al. 21 examined cross-cultural performances on MC and health-related fitness between Portuguese and US children. Results indicated that Portuguese children presented better performances in locomotor performance than US children, but the US children outperformed Portuguese children in throwing and handgrip tests. The authors assumed that cultural differences in PE curricula and sports participation may influence differences in MC and fitness development in these countries. Despite those studies used different motor assessments, Barid et al. 17 used the KTK and Luz et al. 21 used the MCA, both are product-oriented instruments, and provide important results that investigators and PE teachers must consider.
Most cross-cultural studies that address the development of MC highlight the important role of PE classes and sports sessions 28 . For most children, these environments are the opportunity they have to engage in a structured practice that specifically promotes the development of MC 13,29 . So, differences in performance levels between countries, are probably influenced by the curricular contents of PE classes, the availability of games and sports, and cultural aspects.
Comparisons among different cultural contexts may help researchers to understand the mechanisms for MC development and to elaborate new strategies and policy measures to improve and develop MC in school-aged boys and girls. So, the purpose of this study was to compare the southern Brazilian MC levels with the normative values 6 of Portuguese schoolchildren. Beyond that, we were also interested in analyzing the differences in MC between south Brazilian children according to sex and age groups.

Participants
One hundred and forty-eight Brazilian children (80 boys, 68 girls -mean age of 7.81 ± 1.50 years old) participated in this study. Children were recruited from four different cities and schools (private and public) in south Brazil. All children participated in regular physical education classes during school (two classes per week for approximately 45 min each).
Although in Brazil, nowadays schools follow the National Common Curricular Base (Base Nacional Comum Curricular -BNCC) 30 , the data for this study were collected before the end of the period schools had to adapt to those guidelines (2017). The typical PE classes that our sample has focused was team ball games, recreational activities, gymnastics, Brazilian traditional games, and free play. No children in our sample reported participating in sports activities outside of school.

Procedures
Participants were evaluated using the Motor Competence Assessment (MCA) instrument 6 In the SLJ test, participants were instructed to perform the jump with maximal effort starting with both feet together. The distance was measured (in centimeters, using a tape measure glued to the ground) as the distance from the starting point to the location of the heel of the foot closest to the starting point after the jump (in centimeters) -the farthest distance of three attempts was used for data analysis.
In the SHR test, children run at maximal speed to a line placed 10 meters apart, picking up a block of wood, running back, and placing it beyond the starting line. Then running back to retrieve the second block and carry it back across the finish line. The final score was the best time of the two trials.
The BKV test required children to kick a soccer ball (circumference, 64.0 cm; mass, 360.0 g) against a wall with maximum effort. The BTV test required subjects to use an overarm action to throw a size tennis ball (diameter, 6.5 cm; mass, 57.0 g) against a wall with maximum effort. The speed of each attempt (BKV and BTV tests) was measured in meters per second using a radar gun (Pro II STALKER radar gun). The fastest speed of three kicks and the fastest speed of three throws were used for data analyses.
In the JS, participants jump sideways with two feet together over a wooden beam as fast as possible for 15 seconds. Each correct jump scored one point and the best result over two trials was considered. Finally, in the SP test, children were asked to move sideways for 20 seconds using two wooden platforms (25 cm x 25 cm x 2 cm). Each successful transfer from one platform to the other was scored with two points (one point for each step -passing the platform and moving the body to the platform). Participants were given two trials and only the best score was considered. All data were collected between 2017 and 2018.
Three PE teachers, with four years of experience, were trained to collect the data in regularly scheduled classes (each teacher always assessed the same group of tasks). Researchers were trained in the specifications of the assessment's protocols and, at least one of the authors of this study personally supervised every data collection.
All the evaluations followed the original protocol 31 and were done in the school gymnasium, always performed by the same evaluators.
Ethical approval for the survey was granted by the Universidade Federal de Santa Maria Ethics Committee (Protocol: 76336117.0.0000.5346). Oral assent was obtained from the participants and written consent from their parents/guardians, before beginning the experiment.

Data analysis
Normality of the data was confirmed by the Kolmogorov-Smirnov test (p > 0.05). Shuttle run scores were inverted due to the nature of the task (higher values represent lower performance). T-scores were calculated for every test on the southern Brazilian sample. Stability, locomotor, and manipulative category MC scores were computed as the sum of the T-scores from the two tasks, and total MC was calculated as the mean of the T-scores for all tests. To investigate the differences in MC according to age and sex, the sample was divided into two age groups: 4-to 7-years-old, and 8-to 11-years-old. A 2x2 ANOVA (sex by age) was performed to analyze the effects of age group, sex, and their interaction for each of the three MCA categories.
For cross-cultural comparison, our sample was then compared to the Portuguese normative values 6 that used data from two thousand and eighty-seven participants (1,102 boys and 985 girls) between 3 and 23 years of age. Brazilian raw scores for each test were transformed according to the Portuguese normative values (percentiles and z-scores). Chi-Square tests were used to compare the distribution of the Brazilian sample with the Portuguese normative quartiles, and t-tests were used to compare between southern Brazilian and Portuguese standardized results on each test. The Statistical Package for Social Sciences (SPSS), version 25.0, was used, adopting an alpha level of significance of 5%. Table 1 shows the descriptive values of the MC tests by sex and age groups.

Results
The 2x2 ANOVA overall results (see Figure 1), computed with categories and total MCA mean T-scores, showed main effects of sex and age for all analysis of the southern Brazilian children. More specifically, boys outperformed girls and the older age group outperformed the younger for the different categories: stabilization Significant interactions between sex and age were found in total motor competence and in all categories of MC. In total motor competence (F (1,140) = 10.317, p < 0.002) and the stability (F (1,143) = 4.553, p < 0.035) and manipulative (F (1.143) = 14.361, p < 0.001) categories, sexes become increasingly different with age. In the locomotor category, the results for girls were lower in the older age group than in the younger, contradicting the usual tendency (F (1,143) = 9.434, p < 0.003) (Figure 1). Table 2 shows the distribution of the Brazilian sample according to the Portuguese quartiles, and chi-square results regarding that distribution comparison. The frequency analysis indicates that southern Brazilian boys are evenly distributed among the Portuguese quartiles of the JS and SP tests. In the other four tests, the Brazilian boys performed significantly better than Portuguese normative values. Regarding girls, Brazilian girls were unevenly distributed among Portuguese quartiles presenting poorer scores in all tests when compared to Portuguese normative values, positioning mostly in the first and second quartiles, except for the SLJ where they positioned mostly in the third and fourth quartiles, performing above Portuguese normative values. Figure 2 shows the Brazilian mean z-score and 95% confidence intervals (transformed into the Portuguese normative values) for the six MCA tests in relation to the Portuguese z-scores (M = 0; SD = 1). Despite age, when compared to the Portuguese normative reference, Brazilian boys are significantly better in the SLJ, SHR, BTV, and BKV tests. Brazilian girls are significantly worse in the JS, SP, and BTV tests, and significantly better in the SLJ when compared to the Portuguese normative values. There are no differences between Brazilian and Portuguese girls regarding SHR and BKV test.

Discussion
The primary aim of the present study was to compare the motor competence scores of schoolchildren from south Brazil to the Portuguese normative values. We were also interested in investigating the differences between sex and age groups within the southern Brazilian sample.
Our results showed differences in MC between the southern Brazilian and the normative values of Portuguese children (see Table 2). Southern Brazilian boys were significantly above the Portuguese normative values for the locomotor and manipulative tasks, whereas no differences were found in the stability tasks. Conversely, southern Brazilian girls showed poorer results compared to Portuguese girls, which raises some concerns. Their results were significantly lower than Portuguese normative values in all tests except in the SLJ where they were above Portuguese normative values. The high values presented in the SLJ by southern Brazilian girls, particularly the younger ones, are a little bit surprising and might be related to spe-cific characteristics of our sample. In fact, these results are worrying if we consider Luz et al. 21 findings (which uses the same product-oriented instrument as the present study) since the authors showed that Portuguese girls (who outperform Brazilian girls in our study) have lower MC scores than North American girls.
Santos et al. 24 analyzed the differences in Fundamental Motor Skills (FMS) between distinct cultures, using the TGMD-2 (a process-oriented instrument). The results showed that Portuguese children present lower levels compared with Chinese and US children. The findings also showed associations between the curriculum and the number of children mastering FMS. Despite that, no associations were found regarding sports and the mastery of the related skill. Other studies have reported the influence of cultural differences on children's levels of MC 17,32 . Despite those studies used different instruments (process-oriented versus product-oriented) the literature shows that there is frequently a correlation between those types of measures 33 . Thus, the results present a trend that investigators and PE teachers must pay close attention to. Although in Brazil, schools must follow the BNCC 30 , the data was collected before the full implementation of the BNCC guidelines. In fact, Azevedo and Pereira 34 found peculiarities between the PE classes at pri-mary school in Brazil and Portugal. During PE classes, Brazilian girls and boys frequently participate in different activities 35 . Although the BNCC guidelines make no sex distinctions, since they were not fully implemented when our data was collected, boys tended to play soccer games more frequently, whereas girls, who were less motivated to play, usually preferred to run or play games without contact. On the other hand, in Portugal the curriculum allows children to develop basic motor movements, including outdoor activities 34 . Luz and colleagues 21 , highlight that the PE curriculum in Portuguese schools focuses primarily on FMS and games, on developing a multiplicity of motor skills from the age of 3, and the activities that girls and boys engage in during classes are usually the same. Therefore, the differences between PE curricula in Brazil and Portugal, southern Brazilian boys and girls having more time to freely play, extracurricular activities, and the culture itself, may have contributed to the differences between southern Brazilian and Portuguese children. Additionally, although MC in Portugal is part of the curriculum, children have less time for motor activities at school each day 21 .
Although southern Brazilian girls have the same number of PE classes as southern Brazilian boys, our results showed that MC levels are below average compared to their counterparts. Our findings also showed that children's MC increased with age, and boys outperformed girls (see Table 1 and Figure 1), which is in line with the results of previous studies 6,21 . Different studies found similar results, showing that boys present higher MC compared to girls 13,36 . A systematic review conducted by Barnett and colleagues 37 showed that MC is related to age (MC increases across time), but also to sex (boys have higher MC than girls), and socioeconomic background (higher MC is associated with higher socioeconomic status). Controversially, Lopes and colleagues 38 found that boys and girls of all ages showed to have similar MC. Additionally, other studies have reported that boys outperformed girls regarding their motor learning 39 , FMS 9 , and self-perception of motor competence 40 . Kokstejn, Musálek, & Tufano 9 , using the MABC-2 test age Band 1 41 (process-oriented instrument) found that, compared to boys of the same age, 3-and 4-year-old girls had greater balance scores (which comprises the jumping tests) and, there were no sex differences for balance scores in 5-and 6-year-olds, showing that girls can perform balance (including jumping) skills in a similar way to boys. Nobre, Valentini, & Rusidill 40 , emphasized that Brazilian girls have limited opportunities to learn and practice sports skills, presenting poorer motor scores than boys. The literature also indicates that the low levels of MC among Brazilian girls are a widespread problem 4244 . Thus, it is plausible to expect that Brazilian girls may be less encouraged, than boys, to participate in games and physical programs, which in turn negatively affects their MC.   Motor competence has a particularly important role in developing healthy trajectories of life 5,12 since different studies indicate that good levels of MC during childhood are vital for better levels of children's physical activity participation [45][46][47] . According to Stodden's model 5 , children and adolescents who perceive themselves as having low motor skill competence will more probably become involved in a negative spiral of disengagement of physical activities. In fact, reduced levels of MC can enhance lower levels of physical activity, physical fitness and perception of motor competence, and high levels of obesity 5,12 . In this model, although it is considered that there is a reciprocal relationship between the variables, MC is situated as the main variable influencing a positive or negative lifestyle.
Understanding the cultural differences between the PE classes, playgrounds, and other activities that children are involved in can be important to explain our findings, especially the lower levels of southern Brazilian girls MC. The literature shows that girls are less active than boys at different ages and cultures 48,49 , showing that teachers, parents, and all the responsible school staff should pay more attention to this fact. Besides, the expected behaviors for boys and girls have the potential to promote (or not) the development of a set of skills 40,50 . Thus, developmental processes are different regarding sex, and when it comes to MC during schoolyears, it is important to find strategies to counteract what seems to be a girls' disadvantage, trying to identify which opportunities can be available for girls to develop their MC in the environments they attend to more frequently. Thus, promoting more opportunities for girls can enhance their participation in more active and vigorous activities, increasing MC, levels of physical activity, learning, development, satisfaction, and decreasing obesity levels.
The cross-cultural comparisons between southern Brazilian and Portuguese children may provide further information regarding the children's MC contributing to understanding the differences and the strengths of the school policies in each country, and the culture itself. Thus, this research can help all school communities to better understand the mechanisms related to the MC performance between countries and genders.
Despite that, the present study showed some limitations. First, we did not assess the number and type of regular activities done by children on their daily routine, which could help us to understand our findings, especially concerning girls in the SLJ test. Thus, despite being important, this study did not analyze how children move in the different systems (e.g.: home, school, neighborhood, etc.) in which they are present on daily basis 18 . Also, the small number of Brazilian schoolchildren, particularly by a wide range of age (4 to 11 years) should be considered. The environments, and the quality of the settings that children regularly attend (i.e., their home, school, and places where they have extracurricular activities), were also not investigated. The quality of these contexts is probably another determinant of children's motor behavior.

Conclusions
Our results suggest that there is a cultural influence on the levels of MC among southern Brazilian and Portuguese children. Southern Brazilian boys presented better results in four of six of the MC tests (SLJ, SHR, BTV, and BKV), whereas Portuguese girls outperformed the Brazilians in all tests except for the SLJ. The differences between Brazil and Portugal PE curricula, school, free time, and culture probably contribute to these results, providing better opportunities for boys than girls to engage in tasks that develop their MC. In Brazil, girls use their opportunities (to move and play) in a different way than boys to enroll in a variety of movements, games, and physical activities. During recess, girls tend to engage in social activities that do not involve physical activity, instead of playing recreational games, running, or playing team ball games, as boys usually do. The present study provides information on cross-cultural comparison of MC levels in children using the Motor Competence Assessment. Understanding the mechanisms related to the differences in MC performance between countries and genders is important to devise strategies to tackle low levels of MC in target groups that seem to be at greater risk of negative spirals of disengagement of physical activities.