Department of Community Health Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
Corresponding author email: firstname.lastname@example.org
Article Publishing History
Physical activity and dietary habits during childhood play a major role in affecting physical, mental, and cognitive factors in adulthood. Physical inactivity and unhealthy diets may lead to health issues in the future. This study aimed to investigate the relation between dietary habits and physical activity among school children in Saudi Arabia. This cross-sectional study was performed in the capital city, Riyadh of Saudi Arabia and students included in the study were between 5 and 13 years of age who were recruited through an online questionnaire. A total of 122 Saudi students, including 46.8% boys and 53.2% girls, were selected from various schools in Riyadh city. Data on the dietary habits and physical activities of the school children were collected via a questionnaire. The results of the study confirm that 77% of children had a habit of eating fruits and vegetables.
Above 60% of children had a habit of drinking soft drinks, and 84.4% of children showed an interest in eating fast food. Approximately 97% of children were addicted to eating snacks and the majority of students appeared to eat 1 h before going to bed in addition to having a habit of eating late dinners. The students were also actively involved in physical activities with 94.3% of the participants undertaking 1–6 h of physical exercise per week, including running and walking. In conclusion, the current study confirms a significantly high correlation of physical activity on consumption of excess fruits and vegetables as part of a dietary pattern and also on consuming high levels of fast foods and soft drinks. One of the major concerns is connected because of late dinner pattern.
Dietary Habits, Physical Activity, Fruits, Vegetables, School Children
Alafif N. Relation Between Physical Activities and Dietary Habits in School Children of Riyadh, Saudi Arabia. Biosc.Biotech.Res.Comm. 2020;13(4).
Alafif N. Relation Between Physical Activities and Dietary Habits in School Children of Riyadh, Saudi Arabia. Biosc.Biotech.Res.Comm. 2020;13(4). Available from: https://bit.ly/32aDGdY
Physical activity is defined as the skeletal muscular movement of a body which results in energy expenditure. The extensive benefits of participating in physical activities for children include positive physical self-concept, better academic outcomes, boosted global self-esteem, and improved physical and mental health, (Sneck et al., 2019). Physically active students have high energy intakes which balance energy expenditure through a healthy, balanced diet which further provides energy to manage stress (Caldwell et al., 2019). Low intake of dietary fat and high consumption of fruits and vegetables along with increased physical activities can lead to a healthy life without adverse effects during adolescence (Popkin et al., 2012). School children with low levels of physical activity are more likely to develop serious health issues in the long-term such as heart disease and weak bones (PeopleandServices, 2020).
A lack of physical activity can also lead to obesity, which is a commonly known risk-factor associated with low levels of physical exercise (Sun et al., 2020). A strong link was identified between health and education, which is associated with schools promoting physical activity in their students (Tercedor et al., 2017). Physical education plays a major role in an advantageous position for endorsing leisure benefits of physical activities (Polet et al., 2019). The World Health Organization (WHO) has stated that globally, nearly 1.9 million deaths are accredited to physical activity, and they recommend school children should participate in 60 min of physical activity (Dobbins et al., 2013). Schools play an important role in creating a safe and caring environment that sustains healthy practices and also provides opportunities for students to learn and practice healthy eating habits and encourages regular physical activity (School health guidelines, 2011). Physical inactivity combined with sedentary factors and poor diet can lead to weight gain in children (Pozuelo-Carrascosa et al., 2018). The WHO confirms that physical inactivity in the fourth leading cause of global mortality (Alahmed et al., 2018).
Nutritional dietary habits in children are major developmental factors for improving physical, mental, and cognitive levels during adolescence (Kristo et al., 2020). A healthy diet is also used to prevent malnutrition and non-communicable diseases (NCDs). The consumption of processed foods can often modify individual lifestyles, including dietary patterns (Breda et al., 2019). The habit of consuming a balanced and healthy diet starts during childhood can prevent the development of NCDs and chronic diseases in adolescence and adulthood (Tambalis et al., 2019). Acidogenic foods with rich diets include animal meat, fish, cheese, rice, and cereals, and low alkaline foods such as fruits and vegetables support endogenous acid production. Conversely, poor diets and abnormal lipid profile are associated with the development of obesity and cardiovascular diseases (Aslani et al., 2020).
Healthy nutritional diets in small-aged school children safeguards enhanced health status during adulthood (Soheilipour et al., 2019). Breakfast is considered as the first meal of the day and should be considered a healthful diet as well as lifestyle which further can absolutely impact children’s health, specifically, when involving high nutritional fiber, fruits, whole-grain, vegetables and regular products (Yu et al., 2019). But in a recent trend, some nuclear families have modified their lifestyle, including dietary habits. Fast food restaurants are one of the environmental factors that interact with particular characteristics to effect individual weight status. For example, fast food restaurants located near schools can influence body mass index (BMI) outcomes. Junk fast foods are high calorie foods that cause weight gain, resulting in obesity (Asirvatham et al., 2019, Jia et al., 2019).
The WHO estimates that 57% of children in Saudi Arabia are currently physically inactive (Alahmed et al., 2018). Limited studies have been documented about physical activity and other related factors in Saudi school children (Al-Hussaini et al., 2019); there are limited studies in adults, children, and expatriate populations from different regions of Saudi Arabia about a combination of physical activity factors (Al-Hazzaa et al., 2011, Darwish et al., 2014, Alzeidan et al., 2017). To the best of our knowledge, there are currently no studies on school children in the age range of 6–13 years with the combination of physical activity and dietary habits from the Kingdom of Saudi Arabia. Therefore, the current study aimed to determine the association between physical activity and dietary habits in Saudi school children.
MATERIAL AND METHODS
Design of the study: This cross-sectional study was conducted at the female campus of the Department of Community Health Sciences in the College of Applied Medical Sciences at King Saud University in the capital city of Saudi Arabia. A total of 122 children (age range, 5–13 y) were recruited for this study based on a multistage stratified sampling technique. The study participants confirmed their informed written consent (via parent or guardian) before participating in this study. This study was designed as a cross-sectional analytical pilot study performed in Saudi school children to record their BMI, dietary habits, and physical activities.
This study was performed in Riyadh city schools of the north, west, south, and eastern regions from international, non-profit, and national private schools of each region. The inclusion criteria were as follows: children from the Riyadh prominence region with an age range of 5–13 years. The exclusion criteria were as follows: the children 5-13 years of age within the Riyadh prominence. A total of 122 samples were included as the final subset (46.8% boys and 53.2% girls). However, 22 students were excluded owing to unsigned consent forms.
Dietary habits: In this study, dietary habits regarding consumption of fruits, vegetables, junk food, soft drinks and snacks were recorded on a weekly basis.
Physical activities: The student’s physical activities were recorded, including going to the gym, running, walking, and involvement in physical activity classes conducted within school premises, and irregular physical activities.
Anthropometric and other measurements: Obesity was measured by BMI through the combination of weight in kg and height in cm. BMI classifications are based on WHO BMI for ages 5–19 years. Based on the BMI values, children were categorized as underweight, normal-weight, overweight, or obese (Khan et al., 2019).
Statistical analysis: Descriptive statistics were provided as means and standard deviations. Data was analyzed to examine the risk of obesity in Saudi children based on dietary habits and physical activities using SPSS version 15.0. Results were presented as percentages (%).
RESULTS AND DISCUSSION
In this cross-sectional study, a total of 122 students were recruited based on an online questionnaire form. The basic and anthropometric details of school children are presented in Table 1. Both girls and boys aged between 5 and 13 years were included in this study. The mean age of the total students was 9.41 ± 2.61. The results indicated that 54.9% of girls were more actively involved in the physical activity when compared to 45.1% of boys. The mean height and weight of both girls and boys was 125.52±24.3 and 35.1±17.9.
Table 1. Basics characteristics of school children
|Age (Years)||9.41 ± 2.61||NA|
|Sex (Male: Female)||55: 67||(45.1%): (54.9%)|
|Weight (Kg)||35.1 ± 17.97||NA|
|Height (cm)||125.52 ± 24.3||NA|
|BMI (kg/m2)||22.6 ± 11.56||NA|
|Child affected with specific disease||15||(12.3%)|
The mean total BMI was found to be 22.6 ± 11.56 kg/m2. In this study, 12.3% of children were affected with different diseases such as asthma, eczema, allergy, cramps, herpes, epilepsy, epistasis, anemia, and hyperactivity. The literacy rate for the children’s parents was found to be 100%. In this study, a maximum of 86.1% of questionnaires was filled by the mother and remaining 13.9% of questionnaires was documented by father, brother, sister, grandmother, aunt, or uncle. Table 2 shows the BMI categories. Almost 45% students were in the underweight category, 23.8% in the normal-weight category, 18.8% in the overweight category, and 12.3% were obese. In this study, there was no student in the morbid-obesity category.
Table 2. Categorization of children’s body mass index (BMI)
|Types of BMI||Frequencies||Percentages|
The complete details collected regarding food habits in the children are summarized in Table 3. In this study, 77% of children had the habit of eating fruits such as dates, oranges, apples, bananas, and mangoes. Almost 76.2% of children reported eating healthy vegetables, i.e., cucumber, carrot, tomato, lettuce, and other greenery on a daily basis. More than 60% of children had the habit of drinking soft drinks, and 84.4% of children showed an interest in eating fast foods. Nearly 97% children were addicted toward snacks such as sweets, chips, cakes, crepe cookies, doughnuts, chocolates, and sweetened carbonated drinks. All children (1005) had the habit of consuming foods at different times before going to bed. A total of 23.8% of children indicated consuming dinner about less than an hour before bedtime, 41% of children indicated eating dinner an hour before going to bed, and approximately 30.3% of children indicated eating dinner 2–3 h before going to bed. Only 3.3% of children indicated having dinner 4 h before going to bed and finally 1.6% of children indicated having dinner more than 4 h before going to bed (Table 3).
Table 3. List of children’s dietary habits
|Habit of eating fruits||94||77%|
|Habit of eating vegetables||93||76.2%|
|Habit of drinking soft drinks||74||60.7%|
|Habit of eating fast foods||103||84.4%|
|Habit of eating snacks||118||96.7%|
|Dinner time (<1–4+hrs)||122||100%|
The list of physical activities that the children participated in is detailed in Table 4. In this study, 94.3% students were found to be actively involved in physical exercises, including running and walking, on a weekly basis. On regular basis, 6.5% students performed physical activities for a minimum of 1 h, 3.3% for a couple of hours, and 0.8% for 3 h regularly. Only 2.4% of children performed physical activities within their school premises. There were approximately 4.1% children who performed physical activity for 30 min. Approximately 33.6% students performed physical activity on a weekly basis for 1 h; 10.6% for 2 h; 11.5% for 3 h; 4.9% for 4 h; 4.1% for 5 h; 3.3% for 6 and 7 h; 1.6% for 10 h; and 0.8% for 8, 9, 12, 14, or 17 h.
Table 4. List of physical activities within school children
|Physical activity classes||88||72.1%|
|Irregular physical activity||34||27.9%|
In total, 86.1% students made physical efforts and 13.9% did not. However, 38.6% made the effort 1–3 times/week, 13.1% did 4–6 times/weeks, and 34.4% did on a daily basis. However, 13.9% students were motivated by family members. Additionally, 11.5% students participated in the gym and 88.5% were not involved owing to the restricted age limit. Approximately, 72.1% students participated in physical activity classes conducted by their schools and among these, 36.1% and 18% participated for 1-2 and 3-4 times on a weekly basis, respectively and 18% actively participated on a regular basis. There were approximately 19.7% children who were unable to participate owing to a lack of physical activity sessions in a limited number of schools and only 8.2% students did not participate due to the irregulars.
The purpose of designing this study involving school children between the age of 5 and 13 years is that both male and female students have maximum prospects for contributing to numerous types of physical activities in their routine life. The present study was designed to include various schools of native Saudi children. This study aimed to investigate the relation between dietary habits and physical activity among Saudi school children. The results confirmed that >76% of Saudi children prefer to eat vegetables and fruits on a weekly basis, and almost 85% students prefer fast food and snacks. Additionally, the results highlighted that 94.3% students were actively involved in physical activity for 1–6 h per week.
In this study, 31% children were considered to be overweight and/or obese, and approximately 31% of the remaining children were found to be normal with the underweight criteria. Limited studies have been performed within this population of school children in Saudi with the combination of factors of physical activity and sedentary lifestyle related to other factors such as BMI, weight gain as overweight and obesity (Darwish et al., 2014, AL HUSAINI, 2017, ElkhodaryandFarsi, 2017, Al-Nuaim et al., 2012, Alqahtani et al., 2015). A previous study with Saudi children and adolescents has confirmed nominal physical activity (Al-Hazzaa, 2002) and the same author previously conducted a similar study within the Saudi population and documented a 43.3–99.5% prevalence of physical activity (Al Hazzaa, 2004).
A previous study from Saudi Arabia has also concluded that 11%, 42.7%, and 46.3% of children spend 1–<2, 2–4, and >5 h in playing activities, (Darwish et al., 2014), whereas in our study, 33.6% students performed physical activity on a weekly basis for 1 h; 10.6% for 2 h; 11.5% for 3 h, 4.9% for 4 h, and 4.1% for 5 h. The WHO guidelines strongly recommend sustaining physical activity for a minimum of an hour per day in children to prevent certain diseases, (OjaandTitze, 2011). Physical activity is positively associated with lowering the risk of cardiovascular diseases and mortality, (Lind et al., 2017).
Physical activity is associated with the prevalence of weight gain, i.e., overweight or obesity in the children and in our study, only 18% of children were involved in sports activity for an hour and above in a day, which is less than a quarter of the sample, whereas the percentage of obesity and excess weight in our study did not exceed 30%. The 36.6% of students were addicted toward an electronic gadget or watching television for a couple of hours and 33.1% of these spent minimum of 3-4 h on daily basis. Al-Hazzaa et al (2006) performed a study with school children of Saudi Arabia and concluded that an increase in physical activity lowers the chances of developing obesity. Biddle et al (2017) systematically reviewed involving 29 original global studies and concluded that there is a limited association between sedentary behavior and adiposity in both children and adolescents. Zurita-Ortega et al (2017) conducted a study with children in Chile and confirmed that self-esteem was positively associated with physical activity engagement.
A similar follow-up study should be implemented in Saudi community to evaluate the social effects on physical activity. Based on the context of nutritional patterns, this study has documented the expected results on the behavior and choices of children who were enrolled in this study. The results of this study highlight that >75% students had a habit of regular consuming fruits and vegetables and 60%–84% students were addicted to soft drinks and fast foods. The data of the present study are also positively associated with those of previous studies performed by Luszczki et al (2019) and Kristo et al (2020).
The results of our study are similar to those of Nakahori et al., (2016). Numerous studies have been performed in different populations comprising school-going children aged 6–13 years and documented unhealthy eating habits with less physical activity which was shown to be associated with human diseases, (Vilchis-Gil et al., 2015, Lopez-Sobaler et al., 2003). However, based on the literature, several inconsistencies were recorded on the results and dietary effects in children. Extensive research with appropriate sample population is required to shed further insight on the matter.
One of the important issues raised in this study is the time at which dinner is consumed in relation to when children go to bed. Results indicated that 23.8% of children consumed dinner 30 min before bedtime, 41% did so 1 h before bedtime, 30.3% did so 2–3 h before bedtime, and 3.3% consumed dinner 4 h before bedtime, and 1.6% of children did so >4 h before bedtime. The majority of students appeared to eat 1 h before going to bed for sleeping. Okada et al (2019) conducted a study on the habit of eating late dinners in 19,687 Japanese women between the ages of 40 and 74 years and confirmed that 11% of them had late dinners on a daily basis, 22% of women consumed snacks during bedtime, and 8% of women skipped breakfast and these lead to weight gain. Bo et al (2014) confirmed that the consumption of excess calorie intake on a daily basis before bedtime may lead to an increased risk of obesity, metabolic syndrome, and/or non-alcoholic fatty liver disease.
The strength of the present study is to involve complete Saudi ethnicity of school children. The record of 5 days/week helped us document the dietary habits and physical activities (Table 3 and 4) of the children in the study; finally, we have documented the BMI of the student. One of the limitations of this study is the low sample size with limited information. In conclusion, the current study confirms a high prevalence percentage of physical activity and consumption of excess fruits and vegetables along with the habits of consuming soft drinks and fast and junk food, including chips, which may belong to nuclear families. There is a need for future studies with large sample sizes, and it is recommended that restrictions be put on children consuming junk food and soft drinks.
Conflict of Interest: None
Al-Hazzaa H M., Abahussain N A., Al-Sobayel H I., Qahwaji D M, And Musaiger A, Activity P (2011). Physical Activity, Sedentary Behaviors And Dietary Habits Among Saudi Adolescents Relative To Age, Gender And Region. International Journal Of Behavioural Nutrition And Physical Activity, Vol 8, P 1-14.
Al-Hazzaa H, Medicine C. (2006). Obesity And Physical Inactivity Among Saudi Children And Youth: Challenges To Future Public Health. Vol 13, P 53.
Al-Hazzaa H (2002). Physical Activity, Fitness And Fatness Among Saudi Children And Adolescents. Saudi Med J, Vol 23, P 144-150.
Al-Hussaini A., Bashir M S., Khormi M., Alturaiki M., Alkhamis W, And Alrajhi M. Halal T (2019). Overweight And Obesity Among Saudi Children And Adolescents: Where Do We Stand Today? Saudi J Gastroenterol, Vol 25p 229-235.
Al-Nuaim A A., Al-Nakeeb Y., Lyons M., Al-Hazzaa H M., Nevill A., Collins P, And Duncan. Metabolism (2012). The Prevalence Of Physical Activity And Sedentary Behaviours Relative To Obesity Among Adolescents From Al-Ahsa, Saudi Arabia: Rural Versus Urban Variations. Journal Of Nutrition And Metabolism, Vol 417589, P1-9.
Al Hazzaa H J (2004). Prevalence Of Physical Inactivity In Saudi Arabia: A Brief Review. Vol 10, P 663-670
Al Husaini, A (2017). Physical Activity And Sedentary Behavior Relative To Body Mass Index Among School Children In Saudi Arabia. Pediatr Ther, Vol 7, P42.
Alahmed Z, And Lobelo F, Health G (2018). Physical Activity Promotion In Saudi Arabia: A Critical Role For Clinicians And The Health Care System. Journal Of Epidemiology And Global Health, Vol 7, S7-S15.
Alqahtani N., Scott J, And Ullah C. Behaviour A. (2015). Physical Activity And Sedentary Behaviors As Risk Factors Of Obesity Among Rural Adolescents. Journal Of Child & Adolescent Behavior, Vol3, P5.
Alzeidan R A., Rabiee-Khan F., Mandil A A., Hersi A S. And Ullah A. (2017). Changes In Dietary Habits And Physical Activity And Status Of Metabolic Syndrome Among Expatriates In Saudi Arabia. Eastern Mediterranean Health Journal, Vol 23, P 836-844.
Asirvatham J., Thomsen M R., Nayga J R And Goudie R. (2019). Do Fast Food Restaurants Surrounding Schools Affect Childhood Obesity? Vol 33, P 124-133.
Asirvatham J., Thomsen M R., Nayga J R And Goudie R. (2019). Do Fast Food Restaurants Surrounding Schools Affect Childhood Obesity?. Economics And Human Biology, Vol 33, P 124-133.
Aslani Z., Bahreynian M., Namazi N., Shivappa N., Hébert J R., Asayesh H., Motlagh M E., Pourmirzaei M A., Kasaeian A, And Mahdavi-Gorabi A J E., Weight Disorders-Studies On
Anorexia, B. & Obesity (2020). Association Of Dietary Acid Load With Anthropometric Indices In Children And Adolescents. Eating And Weight Disorders – Studies On Anorexia, Bulimia And Obesity, Vol 26, P1-13.
Biddle S J., Bengoechea E G, And Wiesner G. Activity, P. (2017). Sedentary Behaviour And Adiposity In Youth: A Systematic Review Of Reviews And Analysis Of Causality. International Journal Of Behavioral Nutrition And Physical Activity, Vol 14, P 43.
Bo S., Musso G., Beccuti G., Fadda M., Fedele D., Gambino R., Gentile L., Durazzo M., Ghigo E. And Cassader. M. (2014). Consuming More Of Daily Caloric Intake At Dinner Predisposes To Obesity. A 6-Year Population-Based Prospective Cohort Study. Plos One, Vol 9, P1-9.
Breda J., Jewell J And Keller, A. (2019). The Importance Of The World Health Organization Sugar Guidelines For Dental Health And Obesity Prevention. Caries Research. Vol 53, P 149-152.
Caldwell A E., Eaton S B. And Konner. M. (2019). Nutrition, Energy Expenditure, Physical Activity, And Body Composition. The Oxford Hand Book Of Evolutionary Medicine. Vol6, P1- 209.
Darwish M A., Al-Saif G., Albahrani S And Sabra, M. (2014). Lifestyle And Dietary Behaviours Among Saudi Preschool Children Attending Primary Health Care Centres, Eastern Saudi Arabia. International Journal Of Family Medicine, Vol 2014, P1-5.
Dobbins M., Husson H., Decorby K. And Larocca. R. (2013). School‐Based Physical Activity Programs For Promoting Physical Activity And Fitness In Children And Adolescents Aged 6 To 18. Cochrane Database Of Systematic Reviews, Vol 2, P1-180.
Elkhodary H M And Farsi.S. (2017). The Association Between Physical Activity And Obesity Among School Children And Adolescents In Jeddah, Saudi Arabia. Journal Of King Abdulaziz University – Medical Sciences, Vol 24, P 13-27.
Jia P., Luo M., Li Y., Zheng J S., Xiao Q And Luo. R. (2019). Fast‐Food Restaurant, Unhealthy Eating, And Childhood Obesity: A Systematic Review And Meta‐Analysis. Obesity Reviews, Doi: 10.1111/Obr.12944. Online Ahead Of Print.
Khan I A., Jahan P., Hasan Q. And Rao. P. (2019). Genetic Confirmation Of T2dm Meta-Analysis Variants Studied In Gestational Diabetes Mellitus In An Indian Population. Diabetes Metab Syndr, Vol 13, P 688-694.
Kristo A S., Gültekin B., Öztağ M. And Sikalidis. A. (2020). The Effect Of Eating Habits’ Quality On Scholastic Performance In Turkish Adolescents. Behav Sci (Basel), Vol 10, P 1-17.
Lind L., Carlsson A C., Siegbahn A., Sundström J, And Ärnlöv, I. (2017). Impact Of Physical Activity On Cardiovascular Status In Obesity. Eur J Clin Invest, Vol 47, P 167-175.
Lopez-Sobaler A., Ortega R., Quintas M., Navia B. And Requejo, N. (2003). Relationship Between Habitual Breakfast And Intellectual Performance (Logical Reasoning) In Well-Nourished Schoolchildren Of Madrid (Spain). European Journal Of Clinical Nutrition, Vol 57, P S49-S53.
Łuszczki E., Sobek G., Bartosiewicz A., Baran J., Weres A., Dereń K. And Mazur, M. (2019). Analysis Of Fruit And Vegetable Consumption By Children In School Canteens Depending On Selected Sociodemographic Factors. Medicina, Vol 55, P 397.
Nakahori N., Sekine M., Yamada M, And Tatsuse, H. (2016). The Relationship Between Home Environment And Children’s Dietary Behaviours, Lifestyle Factors, And Health: Super Food Education School Project By The Japanese Ministry Of Education, Culture, Sports, Science And Technology. Nihon Koshu Eisei Zasshi, Vol 63, P 190-201.
Oja P, And Titze, J. (2011). Physical Activity Recommendations For Public Health: Development And Policy Context. Epma J, Vol 2, P 253-259.
Okada C., Imano H., Muraki I., Yamada K, And Iso, O. (2019). The Association Of Having A Latedinner Or Bedtime Snack And Skipping Breakfast With Overweight In Japanese Women. J Obes. 2019 Mar 3; 2019:2439571. Doi: 10.1155/2019/2439571. Ecollection 2019
People. (2020). Dc: Us Department Of Health & Services, H. 2020. Physical Activity.Vol 0, P1-6.
Polet J., Hassandra M., Lintunen T., Laukkanen A., Hankonen N., Hirvensalo M., Tammelin T. And Hagger, H. (2019). Using Physical Education To Promote Out-Of School Physical Activity In Lower Secondary School Students–A Randomized Controlled Trial Protocol. Bmc Public Health, Vol 19, P 157.
Popkin B M., Adair L S And Ng, R. (2012). Global Nutrition Transition And The Pandemic Of Obesity In Developing Countries. Nutrition Reviews, Vol 70, P 3-21.
Pozuelo-Carrascosa D P., Garcia-Hermoso A., Alvarez-Bueno C., Sanchez-Lopez M. And Martinez-Vizcaino, V. (2018). Effectiveness Of School-Based Physical Activity Programmes On Cardiorespiratory Fitness In Children: A Meta-Analysis Of Randomised Controlled Trials. Br J Sports Med, Vol 52, P 1234-1240.
Report (2011) School Health Guidelines To Promote Healthy Eating And Physical Activity. (2011) Morbidity And Mortality Weekly Report, Vol 60, P1-76
Sneck S., Viholainen H., Syväoja H., Kankaapää A., Hakonen H., Poikkeus A M., Tammelin, N., Activity, P. (2019). Effects Of School-Based Physical Activity On Mathematics Performance In Children: A Systematic Review. International Journal Of Behavioral Nutrition And Physical Activity, Vol 16, P 109.
Soheilipour F., Salehiniya H J M. Reports, P. (2019). Breakfast Habits, Nutritional Status And Their Relationship With Academic Performance In Elementary School Students Of Tehran, Iran. Med Pharm Rep, Vol 92, P 52.
Sun X., Li Y., Cail And Wang Y. (2020). Effects Of Physical Activity Interventions On Cognitive Performance Of Overweight Or Obese Children And Adolescents: A Systematic Review And Meta-Analysis. Pediatr Res. Br J Sports Med, Vol53, P1-10.
Tambalis K D., Panagiotakos D B., Psarra G., Sidossis L., (2019). Nutrition And Metabolism. Association Of Cardiorespiratory Fitness Levels With Dietary Habits And Lifestyle Factors In Schoolchildren. Applied Physiology, Nutrition, And Metabolism, Vol 44, P 539-545.
Tercedor P., Villa-González E., Ávila-García M., Díaz-Piedra C., Martínez-Baena A., Soriano-Maldonado A., Pérez-López I J., García-Rodríguez I., Mandic S And Palomares-Cuadros, J. (2017). A School-Based Physical Activity Promotion Intervention In Children: Rationale And Study Protocol For The Previene Project. Bmc Public Health, Vol 17, P 748.
Vilchis-Gil J., Galván-Portillo M., Klünder-Klünder M., Cruz M And Flores-Huerta, H. (2015). Food Habits, Physical Activities And Sedentary Lifestyles Of Eutrophic And Obese School Children: A Case–Control Study. Bmc Public Health, Vol 15, P 124.
Yu S Y, And Yang Y. (2019). Nutritional Status And Related Parental Factors According To The Breakfast Frequency Of Elementary School Students: Based On The 2013~ 2015 Korea National Health And Nutrition Examination Survey. Journal Of Nutrition And Health. Vol52, P 73-89.
Zurita-Ortega F., Castro-Sánchez M., Rodríguez-Fernández S., Cofré-Boladós C., Chacón-Cuberos R., Martínez-Martínez A. And Muros-Molina, C. (2017). Actividad Física, Obesidad Y Autoestima En Escolares Chilenos: Análisis Mediante Ecuaciones Estructurales. Revista Medica De Chile, Vol 145, P 299-308.