Basically, childhood obesity has been listed as a common epidemic in public health in developed countries. Considering the possible impact of childhood obesity on children's mental and physical health, the purpose of this study is to explore the effectiveness of diet and exercise interventions in preventing childhood obesity. Combined with the literature related to the public health and relevant non-data collection, this study mainly compares and analyzes the effectiveness of preventive measures for childhood obesity through qualitative research. For example, this study will select obese children in a British kindergarten as a sample. As the participants, these children will be divided into two groups, one group receiving die and exercise interventions and the other group serving as a control group. The researchers will conduct a month-long systematic investigation and record of the two groups of children in order to carry out the corresponding descriptive analysis. By comparing and analyzing the weight changes of two groups of children, the expected results will show the effectiveness of diet and exercise interventions in preventing childhood obesity. Based on the descriptive analysis of the expected results and the problems found in the research, this paper also puts forward corresponding solutions and recommendations. In addition, the ethical issues and importance involved in the research will be discussed in detail as well.
At present, in the field of public health, childhood obesity has been paid more attention. Since 1971, the prevalence of childhood obesity in developed countries has been on the rise. For example, according to a study by Dehghan et al. (2005), the author pointed out that the prevalence of childhood obesity in European countries is relatively low compared with some Mediterranean countries. However, the proportion of obese children is on the rise in both Mediterranean and European countries. In addition, James (2004) concluded that the prevalence of childhood obesity in developing countries is also continuously increasing. There is no doubt that the epidemic of childhood obesity has a profound impact on children's physical and mental health. In general, overweight and obesity are considered to be the result of increased intake of fat and calories. Consequently, the development mechanism of childhood obesity has not been fully understood by relevant researchers and the general public. Nevertheless, in the field of public health, nearly all researchers believed that the prevention may be an important strategy to control the current childhood obesity epidemic. Up to now, most of the methods to prevent childhood obesity have focused on reducing weight by changing the lifestyle of obese people, such as changing diet and increasing exercise. However, whether the intervention measures of diet and exercise to prevent childhood obesity are effective or not? It is a topic worthy of discussion through specific practical research. Based on this, the purpose of this study is to explore the effectiveness of diet and exercise interventions to prevent childhood obesity through qualitative research, so as to put forward more valuable recommendations to prevent childhood obesity. In order to acquire a thorough understanding of childhood obesity, this paper firstly analyzes the current situation, intervention measures and their impact on childhood obesity through literature review. As far as methodology is concerned, this paper mainly adopts the methods of field investigation and comparative analysis. Finally, based on the analysis of expected results, this paper will summarize the whole research process and put forward corresponding improvement suggestions as well.
Basically, as far as definition is concerned, public health researchers have some disputes about how to define childhood obesity. Williams et al. (1992) pointed out that the academic community did not reach a consensus on the critical point of overweight or obesity among adolescents and children. The definition of overweight and obesity has changed with the development of the times, technology and time (Flegal et al, 2002; Kuczmarski et al, 2000). Although the mechanism of obesity development has not yet been fully understood by researchers, the prevalence of obesity will greatly increase when the body's energy intake exceeds its energy consumption. Therefore, obesity can still be defined as an individual having excessive body fat (BF). In addition, besides natural body fat growth leading to obesity, in a few cases, some other factors, including children's obesity-related diseases, hormonal drug treatment, and side effects (such as steroids) caused by drugs, can also lead to a significant increase in children's weight. Medical reasons such as growth hormone deficiency and hypothyroidism can also lead to obesity in children (Link.K, 2004). In short, the causes of obesity are influenced by many factors, such as lifestyle, environmental factors and cultural preferences, which play an important role in the rise of the global obesity epidemic (Hill et al, 1998; Goodrick et al, 1996; Eckel et al, 1998; Grundy, 1998. Obesity and overweight will have a significant and long-term impact on children's physical and mental health (Dehghan, 2005). According to relevant research, it is shown that about 80 % of obese children and young people will continue this obesity trend into their adulthood (Whitaker et al, 1997; Guo et al, 1999). However, overweight and obese adults are more likely to suffer from obesity-related diseases such as hypertension, hyperlipidemia, infertility and impaired glucose tolerance. Moreover, childhood obesity can also lead to an increase in the incidence of psychological disorders such as depression (Daniels, 2005). In a word, due to the increasing prevalence of obesity, the related research on childhood obesity has been developing in depth. Although the researchers have not reached an agreement on how to define obesity specifically, almost all the researchers believe that it is necessary to take some intervention measures to prevent and control obesity, especially in children.
According to relevant public health studies, intervention measures to prevent childhood obesity can be roughly divided into two levels. The first level of prevention focuses on avoiding overweight and obesity itself, while the second level of prevention focuses on avoiding weight recovery after weight loss and preventing individuals already suffering from obesity from further gaining weight (Dehghan, 2005). At present, the main goal of most interventions to control obesity is to change an individual's weight through exercise and diet. Most researchers, including clinicians and public health researchers, agree that interventions may be an effective strategy to control the prevalence of high obesity (Muller, 2001). Specifically, the intervention measures to prevent obesity mainly include the following. First, build an environment suitable for preventing weight loss. Identifying the environment leading to obesity and assessing its possible impact can provide a more accurate and effective choice for preventing weight loss. However, as a specific background, we lack a detailed understanding of the specific family environmental impact (Campbell, 2002). Secondly, diet and exercise interventions are often used to prevent and control childhood obesity. After reviewing the effects of 14 school-based interventions on physical activity knowledge and behavior, Stone et al (1998) pointed out that most of the research variables showed that exercise interventions had significantly improved the prevention of obesity. Diet intervention is also another key strategy to prevent childhood obesity, as children are often the target market for food, especially snacks. In addition, some progress can be made in preventing obesity by restricting TV viewing. Robinson (1999) pointed out that reducing diet in front of TV is as important as increasing exercise activities to prevent childhood obesity. Moreover, the formation of obesity is closely related to the nutritional intake of individuals, so the relevant policies of the food sector can often be used to prevent obesity. For example, food prices can have a significant impact on food purchasing behavior, thus affecting nutritional intake (Guo et al, 1999). In short, in fact, there are many interventions that can be used to prevent childhood obesity. Among them, diet and exercise interventions are used more frequently than others.
As far as the effect of intervention measures to prevent childhood obesity is concerned, the views held in relevant literature seem to be somewhat contradictory. On the one hand, a large number of researchers believed that it is necessary and effective to take corresponding intervention measures for childhood obesity. According to studies by Lobstein et al (2004) and Summerbell et al (2003), the author pointed out that younger children seem to respond more positively to interventions than teenagers and adults. According to the research related to American Diabetes Association (2000), regular physical activity is very important for patients with childhood obesity to lose weight. In addition, for the adolescent children, the strength training brought by sports activities may be of additional benefit to their physical and psychological development. Teenagers can enhance their strength and improve their athletic performance through moderate exercise training, thus obtaining long-term health benefits (Bernhardt et al, 2001). Generally speaking, children with obesity prefer to take part in certain strength training, because it does not need to have too much aerobic capacity or flexibility. And within 2 to 3 weeks, the corresponding strength training can make obese children obtain obvious benefits. On the other hand, a small number of researchers believed that in some controlled trials, intervention measures, such as diet and exercise, can not produce obvious effectiveness in preventing childhood obesity. A study by the American Academy of Pediatrics (2006) showed that some controlled prevention tests for childhood obesity are somewhat disappointing. In the systematic Cochrane database review, three of the four long-term studies combined diet control with physical activity showed no difference for overweight children, while one long-term physical exercise intervention study showed that the weight of overweight children only slightly decreased ( Campbell et al, 2002 ). In short, the vast majority of studies believed that prevention strategies and interventions for childhood obesity may be the key to controlling the epidemic of obesity.
In essence, this study mainly adopts qualitative research methods. Babbie Earl (2014) pointed out that as a scientific method of observation and investigation, qualitative analysis mainly focuses on collecting non-numerical data to explain the research purpose. Marshall Catherine and Rossman Gretchen (1998) also said that qualitative researchers usually rely on some special methods to collect relevant information, such as field research, field notes, participant observation, semi-structured interviews, and document and material analysis. Therefore, on the basis of systematic literature analysis and relevant theories of qualitative research, the practical methods adopted in this research will mainly include participant observation, field notes, descriptive analysis and explanation, so as to collect effective data in the sample population. Because this study is to discuss the effectiveness of diet control and reasonable increase of exercise-based intervention measures to prevent childhood obesity, before carrying out specific field research, the study assumes that diet and exercise intervention measures can effectively prevent childhood obesity. Moreover, this study also assumes that whether the effectiveness of intervention measures to prevent childhood obesity is obviously related to the degree of implementation of intervention measures. In order to highlight the effect of intervention measures, this study mainly adopts the form of traditional control experiment. In the process of specific field investigation and observation, this study will select a primary school in Britain to select a sample population and conduct field observation and research for two months. In addition, besides observing the study as a participant, in order to ensure the accuracy of data collection, the study will also issue specially designed questionnaires to parents of children participating in the experiment to supervise and understand the basic situation of children participating in the experiment in completing specific tasks every day. After the research is finished, through examining the overall data collected by the research, this research will carry out in-depth interpretation and analysis in a structured and descriptive form in order to obtain valuable opinions and insights.
Considering the data collection, on the one hand, during the two-month control experiment, researchers will actually go deep into the school to observe and record the children participating in the experiment through the participant observation method, so as to collect intuitive basic data. On the other hand, through the questionnaire and descriptive interview analysis to the parents of the participants, the researchers will track the actual performance of obese children in diet control and increased exercise activities to ensure the authenticity and validity of the collected data. Considering the sample population required by the study, this study will randomly select 20 children, male and female, suffering from obesity in a British primary school. In short, the total number of samples is 20. During the specific control experiment, the researchers divided 20 participants into the intervention group and control group, with each group including 10 male and female participants. Before carrying out the research, the researchers interviewed the parents of the participants to understand some unhealthy habits that may lead to obesity in children's daily life. Besides, the researchers will issue a self-designed questionnaire to the parents of the participants. The questionnaire mainly involves information related to diet control and increased exercise activities that participants need to complete daily, as well as specific daily weight and weight change data of participants. In addition, researchers will also track and observe the participants and record relevant information on the actual implementation of the intervention measures throughout the control experiment. Regarding sample requirements, all participants need to meet the criteria for obesity. Moreover, the parents of the participants should have sufficient time to assist and supervise the completion of the participants' daily intervention tasks. Of course, this study must be conducted on the basis of voluntary participation of all samples. Based on this, the identified participants will provide more valuable data and information to help researchers understand whether interventions can effectively prevent childhood obesity.
This study will mainly analyze the data by comparing the weight changes of the participants in the intervention group and the control group. On the one hand, the independent variable of the study is "intervention measures" embodied by diet control and increased exercise activities, while the dependent variable is the weight changes of participants in the intervention group. These data will be analyzed mainly through information from the daily records of participants conducted by their parents on the questionnaire. Therefore, based on the control group data without intervention measures, the study can determine the effectiveness of the intervention measures by analyzing the weight changes of participants in the intervention group and the degree of implementation of the intervention measures. In addition, for these data, the study will use the form of scores to measure relevant classification variables, such as weight changes of 1 - 5 kg, 5 - 10 kg and more than 10 kg, and express them in the form of percentages. On the other hand, qualitative data recorded from researchers' field observation and tracking will be qualitatively analyzed by descriptive statistics and methods of reasoning summary. To sum up, combined with the specific data obtained from the control experiment and the descriptive information obtained from actual observation and recording, this study will make a comprehensive analysis and explanation of the two parts in order to reach a final convincing conclusion.
The importance of this study lies in providing the selection of intervention measures and research reference for the effective prevention of childhood obesity. In addition, through the analysis of the relationship between the implementation degree of intervention measures and the effective degree of obesity prevention, the research results are also helpful to put forward effective obesity prevention suggestions directly according to the results.
Although it is necessary to carry out research, there are still a series of basic ethical issues that deserve attention in practical operation. First of all, because the control experiment and related data collection need to cooperate with schools, the research needs to be approved and authorized by relevant responsible persons. Secondly, since researchers will track and record participants' lives, this study should obtain the consent of the participants' parents and teachers. Most importantly, the study will be conducted on the basis of voluntary participation by all participants. This means that participants have the freedom and right to withdraw at any time. In addition, in order to protect the privacy of participants, the study will adhere to strict confidentiality principles.
According to the relevant literature searching and the data collected from the control experiment, the expected research results can be summarized from the following aspects:
First, the study predicts that a certain proportion of participants in the intervention group could not effectively complete the diet control and exercise tasks specified in the control experiment. Due to the relative lack of self-discipline and the influence of the original bad living habits, children with obesity may not be able to provide effective data when carrying out interventions focusing on diet and exercise.
Second, the study predicts that the weight loss of obese children is positively related to the positive implementation degree of diet and exercise intervention. In the intervention group, those participants who can effectively carry out diet control and exercise activities will have significant weight loss changes compared with the control group.
Third, according to the actual observation and recorded information, the study will find that those participants who can keep the habit of diet control and increasing exercise activities are more likely to lose their weight. However, the obesity of the participants in the control group has not been effectively improved because they have not taken corresponding intervention measures.
Fourth, the study predicts that childhood obesity may be related to family environment. The information integrity of the questionnaire can show parents' supervision and attention to children's implementation of intervention measures, which is likely to have an indirect impact on the formation of childhood obesity.
To sum up, taking the prevention of childhood obesity as the research object, the purpose of this study is to discuss the effectiveness of diet and exercise interventions in preventing childhood obesity. In view of this, this study first summarizes the literature related to childhood obesity by using the searching strategies of library and Internet resources. In addition, in order to obtain first-hand direct data, based on the relevant theories of qualitative research, this study mainly conducted the control experiment in a primary school in Britain to analyze the effectiveness of diet and exercise interventions in preventing childhood obesity. Based on the above analysis, this study believed that the effectiveness of intervention measures in preventing childhood obesity has a strong relationship with the positive degree of children in implementing such interventions. Although the basic research ideas have been determined in this study, there are still some limitations to be overcome, for example, the number of samples may be small and the number of participants that researchers can track in the actual observation process is very limited. These problems will be solved step by step in future practical operations.