The relationship between physical fitness and body mass index and waist circumference in 8-10-year-old student boys

Field: Physical Education     Treatment: Sports Physiology

Abstract

The purpose of this research was to investigate the relationship between physical fitness and body mass index and waist circumference in 8-10-year-old student boys in Rasht city. For this purpose, 324 students were selected by cluster-random sampling method and participated in the research. At first, height (138.36±7.13), weight (37.79±9.87), body mass index [1] (19.50±3.71) and waist circumference [2] (67.22±9.08) of subjects were measured and recorded. Then, the physical fitness variables, which included the standard one-minute sitting and sitting tests, standing long jump, and 4 x 9 meter running back and forth, were performed and the results were recorded and analyzed. Due to the non-normality of the data distribution, Spearman's correlation test was used to check the correlation between the research subjects (P?0.05). The results of the present study showed that there was a positive and significant correlation of 0.35 between the 4 x 9 meter back and forth record and the WC of students, a negative and significant correlation of -0.43 between the long jump record and WC, and a negative and significant correlation of -0.20 between the sit-up record and WC, which shows that the scores of selected factors of physical fitness decrease with increasing WC. Also, there was a positive and significant correlation of 0.35 between the 4 x 9 meter sprint record and BMI, a negative and significant correlation of -0.38 between the long jump record and BMI, a negative and significant correlation of -0.18 between the one-minute sit-up record and BMI, a negative and significant correlation of 0.15 between physical fitness and BMI, and a negative and significant correlation of 0.23 between physical fitness and WC. These results indicate the essential need to improve physical fitness among students.

Key words: waist circumference, body mass index, physical fitness

1-1- Introduction

Great advances in technology and mechanization of life are features of today's modern world. The consequence of the mechanization of life is the poverty of movement, which is one of the most important problems of today's mankind from the point of view of health. This phenomenon is one of the risk factors of obesity. In the last fifty years, research has shown that the most important factors that cause disability and premature death have changed from infectious and contagious diseases to chronic diseases and dementia (121, 115). In 2001, chronic non-communicable diseases accounted for 0.95 of the world's deaths. Obesity is one of these diseases. During these years, on the one hand, due to the increase in the economic power of industrial societies and excessive prosperity in life, excessive consumption of fats, meat, sugar, salt, and tobacco consumption has become common, and on the other hand, the amount of physical activity has decreased. In total, the above factors have caused an increase in the prevalence of non-communicable diseases and the risks caused by them (141). Regardless of how we look at obesity as a disease or only as a risk factor, people with overweight and obesity face a wide range of diseases and complications that require accurate diagnostic and treatment measures based on scientific evidence. The impact of obesity on social and occupational activities and the quality of life in general also increases its socio-economic burden, so that more than 10% of health-treatment costs are attributed to the direct and indirect effects of obesity. Today, obesity as a main problem of the health system, along with diabetes mellitus, has been named as the twin epidemic of the 21st century. As the prevalence of obesity in the world has doubled over the past three decades. 65% of the world's population lives in countries where weight gain and obesity cause more deaths than underweight. Every year, about 2.8 million adults in the world die due to obesity. In addition, 44% of the burden of diabetes, 23% of the burden of ischemic heart diseases and between 7 and 41% of the burden of some cancers are attributed to overweight and obesity (7).. While these countries are still plagued by the problems of infectious diseases and malnutrition, the prevalence of risk factors of non-communicable diseases, including overweight and obesity, is increasing, especially in the urban population of these countries. The increasing trend of obesity in children and adolescents is also a special concern for the health of the society. The numerous medical and psycho-social complications of obesity and overweight in children and adolescents and the heavy burden imposed on society in this regard emphasize the importance and necessity of its management and prevention at sensitive ages (66). It is much easier to shape and change behavior in childhood and adolescence than in adulthood (136). In addition, due to the possibility of continuous and regular contact with teenagers in educational environments, schools can play an active and effective role in promoting their health. Educations that aim to prevent risky behaviors and unhealthy habits in life in the early years of life should emphasize learning a healthy lifestyle; Because an unhealthy lifestyle is the basis of many diseases and disorders (80).

1-2- Statement of the problem

Years ago, obesity was considered as a disease for middle-aged people, but recently, the prevalence of obesity in children and school-aged children has also progressed (49). Obesity is a multifactorial phenomenon that results from the interaction of several complex factors, including heredity and behavioral components, especially physical activity and diet, which is influenced by social, cultural, and environmental factors (37). These two lifestyle habits, in addition to obesity, are known as the most important risk factors for several chronic diseases such as type 2 diabetes, cardiovascular diseases, etc. (135).

Studies have shown that obesity in childhood and adolescence is associated with a high risk of obesity in adulthood, and part of this may be due to the continuation of unhealthy lifestyle behaviors such as poor diet, lack of physical activity, and Increase in sedentary behaviors until adulthood (131). The increase in the prevalence of obesity in children and adolescents is the result of an imbalance between energy intake and energy expenditure (79). During the past decades, the energy expenditure in children has decreased (130) and the pattern of physical activity in adolescents has also changed, as a result of the increase in time spent watching television, the emergence of video games and the Internet, as well as the decrease in the duration of physical activity in schools and communities (53). Changing to modify such modifiable behaviors starting in childhood can have a potential role in reducing the obesity epidemic and have important long-term and short-term healthy supportive effects; Therefore, preventing obesity and improving healthy lifestyle habits in children is a high priority (97).

On the other hand, improving physical fitness is a public health priority to reduce the significant and increasing prevalence of lifestyle-related diseases in developing and developed countries. Since physical activity is an important factor in controlling body mass, there is a great desire to investigate the relationship between physical activity and body composition of children and adolescents, as well as the importance of physical activity in maintaining health and well-being (108). Iran is a country with a large urban population, and like most countries that are involved in rapid economic and demographic changes (45), non-communicable diseases, especially cardiovascular diseases, are the main cause of death in Iran (21). According to the National Health and Nutrition Examination Survey (NHANES), the prevalence of overweight among children aged 6 to 13 years has increased from 7 to 11% and among adolescents aged 11 to 19 years from 5 to 11%. In most research reports, obesity and overweight are considered based on the 85th and 95th percentiles of body mass index [2] (BMI) based on age and sex (World Health Organization, 2005). In another study, the prevalence of overweight in teenagers aged 12-19 was 15.5% and for children aged 6-11, it was 15.3% (71). In children living with adults, it has an effect on their obesity as well as the prevalence of obesity among adults (120). In the last two decades, overweight and obesity have been increasing in most developed and developing countries (67).