Regular practice of physical activity can contribute to the improvement of various components of health-related physical fitness, such as strength, muscular endurance, cardiorespiratory endurance, flexibility and body composition. 1 These improvements may favor mainly the control of body fat, but also maintain or improve neuromotor function. 2 These changes facilitate performance in various tasks of everyday life and, consequently, provide better health and quality of life. 1,2

In contrast, reduced levels of physical activity seems to favor the gradual development of many chronic degenerative disorders such as obesity, diabetes, cardiovascular disease, hypertension, and many others, at increasingly earlier ages. 3,4 The high prevalence of obesity in children and adolescents is a serious public health concern. According to the International Obesity Task Force, at least 177 million children and adolescents are overweight or obese worldwide. This number equates to greater than one in ten youth being overweight or obese globally. 5

A study conducted by Wang et al. 6 in countries with different stages of socioeconomic development revealed a significant increase in the prevalence of overweight children and adolescents in recent decades. Among adolescents, the observed increases in overweight of significant magnitude were: 62% in the United States (16.8–27.3%) and 240% in Brazil (from 3.7% to 12.6%). However, most studies involving the different components of physical fitness have adopted traditional analytical procedures based on normative data, which greatly limits a more careful analysis of data. 7

Little is known about the relationship between different elements of physical fitness and overweight or obesity in Brazilian adolescents. For example, we do not know if lack of flexibility, muscular endurance of the abdominal muscles, or aerobic fitness, which are associated with poor physical function and health in adolescents, are related to degree of overweight in this population. Similarly, there are few studies on the interaction between cardiovascular fitness and related indicators of health in adolescents who are obese. 7

Accordingly, the aim of this study was to determine the association between of physical fitness, socio-demographic factors and overweight prevalence of adolescent schoolchildren ages 14–17 years from urban and rural areas in Tucuruí-Para in northern Brazil.

Table 3 shows the anthropometric characteristics of students (mean, standard deviation, and statistical F) according to gender and chronological age. For the isolated effect of gender (p < 0.05) and the isolated effect of age (p < 0.05) statistical differences were found in body mass and height. Also, the interaction between gender and age on body mass and height was observed (p < 0.05).

Table 4 shows the values (M, SD and statistical F) regarding the test of HRPF in adolescents by gender and chronological age. There were only isolated effects of gender (p < 0.05) in the abdominal and cardiorespiratory fitness tests.

Table 5 shows the proportion of students with inadequacy in each component of HRPF according to socio-demographic variables (gender, age, socioeconomic status (SS), area of residence and BMI).

Association was found between flexibility, muscular strength and endurance, and cardiorespiratory fitness (p < 0.05). In testing flexibility and cardiorespiratory fitness, a higher proportion of inadequacy was found in the urban area schools, while the highest proportion of inadequacy in muscular strength and endurance was found in the rural area schools.

The association between the inadequate flexibility and associated factors are presented in Table 6. Association was found between physical quality and area of residence, in which the students from urban areas had a 55% (95% CI = 1.12–2.12) more likely inadequacy of this variable when compared to the rural area students. When the analysis was adjusted for all variables, it was noticed that the area of residence remained associated with inadequate flexibility. These results revealed that the students from urban areas were 56% (95% CI = 1.12–2.16) more likely to have inadequate flexibility as compared to the rural school children.

Table 7 presents the results of a logistic regression analysis test of muscular strength and endurance in relation to socio-economic factors. There was an association between muscular strength and endurance and area of residence. These odds ratio results demonstrated that the chances of the students presenting with inadequacy in this variable was 8.99 (95% CI = 1.12–72.30) times higher among schoolchildren in rural compared to schoolchildren in urban areas. When the analysis was adjusted, it was realized that the area of residence remained associated with the physical quality, in which the students from rural areas were almost ten times (95% CI = 1.20–83.20) more likely to have inadequate muscle strength and endurance compared to students in urban areas.

Table 8 shows the association of cardiorespiratory fitness factors associated with poor schoolchildren. As with other variables, cardiorespiratory fitness was associated with area of residence. The OR findings in Table 8 indicated that children living in urban areas had 91% more risk of inadequate cardiorespiratory fitness than those from rural areas.

Fig. 1 shows the proportion of adolescents who did not meet the health criteria established for body composition. The results showed that 25.1% of teenagers find themselves with inadequate body composition, with the proportion of teenagers with inadequate body composition being higher (p < 0.05) for males (32.3%) than for females (18%).

Fig. 1.

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Proportion (%) of students who did not meet the healthy criteria established for body composition. * p < 0.05 for comparison between genders.

Fig. 2 shows the proportions of adolescents who did not meet the criteria established for each test investigated, for flexibility, that 40.8% of adolescents did not meet the criteria for health. Significant differences were found between genders at the age of 14 years, with the proportion of inadequacy being higher in females than in males (p < 0.05). In the test of muscular strength and endurance, we observed that 98.5% of adolescents ranked below the cutoff for health. Significant differences were found between genders at the age of 15 years (p < 0.05), with a higher proportion of female adolescents (99.2%) than male adolescents (97.7%) being below the recommended minimum criteria for health. In cardiorespiratory fitness, 35.4% of adolescents had performance below the established cutoff for health. Gender differences in the proportions were observed at ages 14 and 16 years. These findings indicate that a greater proportion of adolescent males than adolescent females at the age of 14 years and a greater proportion of females than males at the age of 16 did not meet the minimum criteria recommended for health.

Fig. 2.

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Not meeting criteria for health (%) of students who did not meet the criteria for health established for each test according to gender and age. * p < 0.05 for comparison between genders.

Regarding the general classification for health, there was a high prevalence of adolescents who did not meet both criteria established for health as determined from the three motor tests. These results indicated that 99.6% of teenagers have not reached the desired level for health.

The aim of this study was to determine the associations between physical disability, socio-demographic factors, and nutritional status of schoolchildren in Tucuruí, PA. This is the first study of this kind to be conducted in the northern Brazil. Flexibility, muscular strength and endurance, and cardiorespiratory fitness were associated with the area of domicile. The study revealed that most inadequate flexibility and cardiorespiratory fitness were observed among schoolchildren in urban areas, a fact that is proven by the lifestyle which children in urban areas have in relation to children in rural areas. In contrast, most inadequate abdominal strength was observed in those children from rural areas. A study of adolescents in rural and urban areas in the north and west of Santa Catarina (Southern, Brazil) reported a greater inadequacy of muscular strength and endurance and cardiorespiratory fitness in adolescents in urban areas, while flexibility was similar between areas of residence. 13

Since urban adolescents have lower HRPF in the areas of flexibility and cardiorespiratory fitness than their rural peers, it is assumed that the lifestyle adopted by the schoolchildren in this area of residence contributes significantly to the performance of the tests. Despite not having been verified, the possible factors that influence the performance on the tests are the labor activities, customs and habits that are cultivated in the rural sample, and that these interact positively with HRPF. However, other habits and practices with little energy expenditure that predominate in the urban areas tend to negatively influence health-related physical fitness in this sample city. Even though mechanization has decreased energy expenditure of residents in agricultural communities, caloric expenditure can be considered much higher in rural activities than in activities common in urban areas. 14

In the flexibility test, the students of the urban area had a 56% greater chance of inadequacy in relation to the rural area students. This result is explained by the fact that the students in rural areas still do not have access to technological advances, using active transportation (walking or cycling) in commuting to school, and work in agriculture, mostly subsistence, in which agricultural machinery is not often used. Furthermore, the municipality of Tucuruí-PA does not offer Internet throughout the countryside, and access to television is only possible through satellite dishes, which limits access to passive leisure activities. In contrast, in urban areas the population has ready access to passive forms of leisure activities resulting from technological developments (TV, Internet, Lan House).

Low levels of flexibility are worrying, as low levels of flexibility increase the risks of pain in the lumbar region, a higher incidence of postural deviations, and poor academic performance. 15,16 A longitudinal study in Finland found that, after 25 years, children with low levels of flexibility during school reported greater back pain in adulthood. 16

With respect to abdominal strength and endurance, students from rural areas had a ten times higher chance of inadequacy in this measure than the inner city schoolchildren. Similar results were found in a study of schoolchildren in southern Brazil, where the students from rural areas had the worst performance in the test of abdominal strength and endurance. 17 In contrast, studies of rural and urban adolescents living northwest of Santa Catarina and Rio Grande do Sul were reported to have worse performance on abdominal strength tests than adolescents in urban areas. 18

In the cardiorespiratory test, students in the urban area had 91% higher chance of inadequacy than those in rural areas. These findings are consistent with other studies conducted with samples of Brazilian children and adolescents. 17,18 Another study reporting worse performances of students from urban areas compared to rural areas was conducted on nine to twelve year old children in Mexico. 19 Low levels of cardiorespiratory fitness is worrisome, especially because it is association with high levels of Metabolic Syndrome risk: high cholesterol and triglycerides, high blood pressure, insulin resistance, and increased risk for obesity. 20–23

Among the independent variables (gender, age, SS, area of residence and BMI), the only one that was associated with components of HRPF was the area of domicile, which explained most of the variation. SS, which may be taken as contextual variables, was not associated with the components of HRPF. This suggests that performance on tests that make up the HRPF of the school children of Tucuruí-PA may be more related to environmental features associated with living in a given area.

The results of this study revealed an association between components of HRPF and area of residence. These results indicate that the students from rural areas had better cardiorespiratory fitness and flexibility, while better abdominal strength and endurance was found in those of the urban area. Therefore, the school can play a key role in the development of HRPF through physical education classes, since this location is perhaps the only location where we have all adolescents participating in programs oriented toward exercise.

It was observed that the smaller schools are not able to offer these programs, because they do not have adequate physical spaces, or the materials needed for physical education.

Considering the low proportion of students meeting adequate health in either setting, it is important to develop an integrated program of physical activity where students, family members, teachers, and administrators play an active role in promoting physical activity and healthy lifestyles.

Increasing physical activity to nationally recommended levels is a challenge for many middle and high school administrators across the nation. Even smaller amounts of physical activity in school may decrease obesity levels significantly. It is essential to consider children at high risk for obesity, such as minority females, when developing such physical activity programs.

The authors have no conflicts of interest to declare.