The prevalence and some associated factors of silicosis among employees working in one factory in thai nguyen province, 2020

13 Frequency of students engaging in moderate to vigorous physical activity for at least 60 minutes each day in the last 7 days by gender 42 Table 3 14 Activities students attending in t

DUONG TRUNG Di e

DIETARY INTAKE AND PHYSICAL ACTIVITY

OF ELEMENTARY SCHOOL CHILDREN

TN’ HA NAM AND DIEN BIEN PROVINCES IN 2020

Major code : D720302

THESIS OF GRADUATION MEDIC AL DOCTOR

COURSE 2015 - 2021

Supervisor 1 Assoc Prof PhD Tran ThuyNga

2 Assoc Prof PhD Pham Van Phu

HANOI-2021

challenging field, and it presented many difficulties to me when 1 decided to do my thesis os it But as a result OỈ*it I did not only gain more knowledge, but also more skills The implementation would not be possible if I did not receive the assistance

of several individuals and organisations Thus I would like to express my sincere gratitude to all of them even though it 18 unpossible to list them all

First and foremost I would like to express my heartfelt gratitude and appre­ciation to Assoc Prof Tran ThuvNga head of Department of Micronutrients Na­tional Institute of Nutrition for her invaluable guidance relentless encouragement expert suggestions constructive criticism, and supervision, all of which were essen­tial in completing this thesis

1 am thankful to Assoc Prof Pham Van Phu from the Department of Nutri­tion Institute for Preventive Medicine and Public Health for his great interest, en couragement supervision, and helpful advice on thesis progress

I would like to express my deepest thanks to the Managing Board Depart­ment of Training Hanoi Medical University' who had created a welcoming and wonderful environment in the school for the past six years I wish to thank all the teachers in die Department of Nutrition Institute for Preventive Medicine and Pub­lic Health, Hanoi Medical University for their valuable information pro'ided by them in their respective fields I am grateful for their cooperation during the period

of my assignment

Finally I would like to thank my wonderful family and friends for their un­wavering support during this ordeal Your unwavering love and support gave me the strength to keep going

Hanoi 2021

I declare that this thesis represents my work and has not been submitted for any degree in any university previously All the sources of information which have been use in the thesis and external contribution are fully referenced and acknowledged

Hanoi 2021

Duong Trung Due

IN TRODU CTION

CHaPTE R 1: LITERATURE RE VIEW 3

1.1 Dietary intake

1 I 1 Definition of dietan-intake

I 1.2 Methods of dietary intake assessment 3

1.1.3 Recommended dietin’ allowances for elementary school children Ó 1.2 Physical activity

1 2.1 Definition of physical activity - 9

I 2.2 Methods of assessing physical activity 10

I 2.3 Recommendations on physical activity for elemental} school children 13 1.3 Previous studies on dietary intake and physical activity of elementary school children 15 1 3.1 In the world 15 I 32 In Vietnam 17

CHAPTER2: RESEARCHsu BJECTS AN D METH ODOLOGY 19 2.1 Study subjects: 19 2 1.1 Inclusion criteria 19 2 1.2 Exclusion criteria 19 2.2 Study time and study sites 19 2.3.Methodology 19 19 2.3.2 Sampling .19

2.5 Potential errors and solutions 23

2 5.1 Potential errors 23 2.52 Solutions - - 23

2.6 Dau management and analysis _ .24

2.7 Ethical issues , 24

CHaPTE R 3: RESULTS 25

3.1 Characteristics of research subjects 25

3.2 Dietan- intake of research subjects — 26

3.3 Physical activity of research subjects 40

CHAPTER 4 DISCUSSION 48 4.1 Dietan’ intake of the research subjects 48 4 2 Physical activity of the research subjects 53

CONCLU SION 58

1 Dietar,- intake of the elementary- school children in Ha Nam and Dien Bien province in 2020 58

2 Physical activity- of the elementary school children in Ha Nam and Dien Bien provincem 2020

RECOM MEND AHO NS

REFERE NCES

APPEND1X

Physical ActivityRecommended Dietary AllowancesWorld Health Organization

Table 3.2 Food consumption of students by province — 26

Table 3 3 Energy and macronutrients intake by province 27

Table 3 4 Micronutrients intake of the students by province 28

T able 3 5 Food consumption of students by gender 32

Table 3 6 Energy and macronutrients intake by gender 33

Table 3 7 Micronutrients intake of students by gender 34

Table 3 s The proportion of protein and lipid intake by province and gender 39 Table 3 9 Average of PAQ score of students by province and gender 40

Table 3 10 Level of physical activity of students by province 40

Table 3-11 Level of physical activity of students by gender 41

Table 3 12 Frequency’ of students engaging in moderate to vigorous physical activity for at least 60 minutes each day in the last 7 days by province41 Table 3 13 Frequency of students engaging in moderate to vigorous physical activity for at least 60 minutes each day in the last 7 days by gender 42 Table 3 14 Activities students attending in the past 7 days by province 43

T able 3 15 Proportion of children cycling or walking to school by province 44 Table 3 16 Activities children doing during school break-time bv gender 44

Table 3 17 Mean time children doing sedentary activities by province 45

Table 3 1 s Mean time children do sedentary activities by gender 46

Table 3 19 Electronic device students use most often by province 46 Table 3 20 Average evening sleeping time of students by province and gender 4 7

Figure 3.2 Proportion of micronuuients meeting the RDA by province - 31

Figure 4 Proportion of micronutrients meeting the RD A by gender 37Figure 3 5 The balance of energy substances intake of students by province 3S

Background & objectives: Dietary intake and physical activity (PA) are not only directly affected to children's growth, but alio indirectly affected to their cognitive abilities and stature development This study aims to describe the dietary intake and assess the PA of elementary school children

Methods: A cross-sectional study involved 248 students aged 7-10 years in Ha Nam and Dien Bien provinces from October to November 2020 In which 225 die­tan’ intakes were collected by 24 hours dietary recall method The PAQ question­naire was used to assess the students’ PA

Results: The mean energy consumption IS under the RDA (1367 6 2 568 I Kcal) Total protein consumption is high (143 9% of the RDA) Lipid and carbohydrate are not meeting the RDA Calcium, magnesium, vitamin Bl B2 B6 folate, vitamin A

D are under the RDA The energy-generating substance structure is balanced

(P L c=16 4 23 4 60 2) The average PAQ score is 2.9 * 0 6 points The majority of

studenrs are moderate-active (81 8*o) whereas 18.2% are low-active Students spend an average of 1.2 -1 8 hours on sedentary activities every day Snrdents in Ha Nam spend more time on sedentary activities than students in Dien Bien

Conclusion: The dietary intake of elementary school children aged 7-10 years in

Ha Nam and Dien Bien did not meet the RDA for energy lipid carbohydrate and some micronutrients However the composition of macronuuieats reached the RDA Majority’ of students are moderate active

Keywords: dietary intake, physical activity, elementary school children Ha Nam, Dien Bien.

Dietary intake plays an important role in nutritional status and people’s health A healthy diet is considered crucial for elementary school children It does not only directly affect to their growth, but also indirectly aflcci to children's cogni­tive abilities and learning results [1] Several studies around the world found that multiple dietary inadequacies are frequent among children from developing coun­tries (2| 13J hl Vietnam, a study by Tran Khanh Van et al ID 2017 conducted in Thai Nguyen province found that the dietan- intake of elementary school students aged 7 to 10 years did not meet the recommended dietary allowances of the Nation­

al Institute of Nutrition in terms of both energy and proporúcu of macronuưients the study also found the lack of micronutrients in the diet [4] Lack or excess nutri­ents in primary school children all leads to nutritional disorders such as malnutrition and micronutrient deficiency Nutritional disorders are thought to be caused mostly

by an inadequate diet (5)

In addition to a healthy diet, children will benefit horn a regular schedule of physical activity The role of physic al activity in nonnal growth and development is obvious Increased physical activity, especially at school age aids in optimal height and stature development [6J Furthermore, several studies aroiad the world have shown that physical activity can help minimize the risk of cardiovascular disease metabolic disease and mental disorders [7Ị, [8]

However several studies around the world and in Vietnam have shown that the proportion of students who meet the recommendations of physical activity is still low According to study conducted by Zinuno L et al in 2017 only 39% of primary school students in Qatar engaged in moderate to extreme physical activity for 30 minutes or more a day, students spend an average of 58 1% of their daily time on sedentary activities [9] In Vietnam 2016 Do Van Dung et al conducted a study on 619 grade 5 students in Ho chi Minh City, finding that 18% of students

did Dứt engage in physical activity, male students axe more active than female Stu dents, and sedentary activities are common in both genders (to)

Adequate diet and physical activity are the prerequisites for children’s growth Economic growth also contributes to social changes, including changes in children’s eating and exercise behaviors As a result, many countries around the world are interested in studying children's dietary intake and physical activity It provides a scientific basis for the government to establish interventional strategies and other health strategies to improve children's health However, in Vietnam, stud’ ics on elementary school childrens dietary intake and physical activity arc still not really interested For the above reasons, we conduct the research “Dietary intake and physical activity of elementary school children in Ha Nara and Dien Bien pros Inces in 2020“ with two following objectives:

1 To describe the dietary intake of elenarntary school children in Ha Nam and Dien Bien provinces in 2020

2 To assess the physical activity of elementary school children m Ha Nam and Dien Bien provinces in 2020

CHAPTE R I: LITERATI RE REVIEW1.1 Dietary intake

1.1.1 Definition of dietary intake

Dietan intake is the amount of food consumed in one day to fulfill the body’s energy and nutrient requirements [111

The per-subject intake was determined by the amount of meals consumed per day the distribution of meals at different times of the day taking into consideration meal timing and a balanced distribution of energy ratios among meals [111

1.1.2 Methods of dietary intake assessment

Dietary assessment is an evaluation of food and nutrient intake and dietary pattern of an individual or individuals in the household or population group over time It is on? of the four approaches in nutrition assessment to evaluating the nutri­tional Status of individuals comprehensively The other three are anthropometries biochemical parameters andclinical examination (12]

Dietary intake can be assessed by subjective report and objective observa­tion Subjective assessment is possible using open-ended surveys such as dietary recalls or records or using closed-ended surveys including food frequency question­naires Each method has inherent strengths and limitations Subjective dietary as­sessment methods that assess an individual's intake include the 24-hour dietary' re­call (24 HR) dietary record (DR), dietary history and FFQ Data are collected with the help of a trained interviewer OI by self-ieport [13]

24 hours dietary recall (24HR)

The 24HR is conducted in an in-depth interview manner and typically re­quires 20 to 30 minutes to complete a single day recall Subjects are asked to report all foods and beverages consumed in the past 24 hours This can be done via tele­

phone or àce-to face interview Trained staff must conduct the interview to prompt for details such as cooking methods and portion si2es [2] [4]

Detailed data about food preparation methods, ingredients used in mixed dishes and the brand name of commercial products may be required according to the research question The amounts of each food consumed are estimated in refer­ence to a common size container (e g., bowls, cups, and glasses), standard measur­ing cups and spoons a three-dimensional food model Of two-dimensional aids such

as photographs One advantage of the 24HR is that a relatively minimal burden is imposed on respondents However an inevitable limitation is that all information depends on the respondents memory and the skills of a well trained interviewer to minimize recall bias [11), [13]

Another limitation is that this method is mainly focused on short-term intake but long-tenn dietary exposure is especially of interest when investigating chronic diseases Thus, to measure average intake, multiple 24HRs are needed Repeated measurement not only requires a lot of resources and time, but survey repetition can also influence n respondents* diet A further disadvantage is from the open-ended format which requires significant effort during data collection entry and analysis The research team must carefully review each questionnaire to ensure that all rec­orded da1a is included After initial review, all foods and mixed dishes consumed according to the detailed descriptions of the respondents should be matched and coded with the most appropriate food listed in the food composition database Moreover, the quantity of food consumed should be converted to its actual weights When the reported information is changed to the corresponding food code and weight actual intakescan be calculated (11) (13)

Dietary record

Subjects record all food and beverages consumed over three consecutive days (two weekdays and one weekend day) The consumed items can be measured using a scale or other household items such as measuring cups or spoons, or esti­

mated using a portion-size guide Trained staff must provide detailed instructions on hosv to rec ord intake (IS]

The main advantage of dietary record is its potential to collect accurate quan­titative information on individual foods consumed during die registration period Because of the quality of the dietary data the dietary record is considered to be the gold standard of the dietary methods and is often used as 3 reference in calibration

or validation studies using other less involved and less expensive methods The weighted dietary record provides more precise estimates of intakes for individuals

analytes As foods are recorded as consumed it is less likely to omit forget food items and moreover the description thereof is more accurate When the dietary rec­ord uses open ended questions, abundant information can be collected and analyzed

in various aspects For example if sufficient days are recorded day-to-day variation can be studied Also, detailed descriptions of the foods consumed, and all eating oc­casions are provided It can be easily applied to diverse groups with a wide range of eating habits and may be used to estimate the average intake of a certain population since provides excellent estimates for energy, nutrients foods and food groups Die­tan* record is suitable in metabolic and intervention studies (131(16]

Since the diet varies greatly from day to day the reported data can only rep­resent the current diet, not the normal diet However, if the procedure is repeated, the usual intake may be calculated Those who may fill out dietary record (inter­viewees or caregivers) must be both inspired and literate (if done on paper) which can restrict their use in certain populations (people w ith low literacy, immigrants with low language skills, children elderly people with difficulty writing ) Be­cause the DR requứe high cooperatice limits the type of population that can be ap­plied and this could compromise the generalizability of the results to the wider population [13J [16]

Dietary history

To assess individual long term die tan’ intake Burke developed a dietan’ his­tory method in 1947 (17) This method requires that subjects complete a 24HR 3- day food diary, and checklist of foods usually consumed Highly skilled profession­als arc required to collect information on the participant's usual diet using an in- depth interview (approximately 90 minutes to complete) Thus this method is rarely used in epidemiological studies (13) (17)

Food frequency questionnaire (FFQ)

The FFQ is an advanced form of the checklist in dietan’ hrstory method and asks respondents how often and how much food they ate over a specific period Pre­senting about 100 to 150 foods, this questionnaire takes 20-30 minutes to complete and can be self-administered or collected via interview This method enables the as­sessment of long-term dietary intakes in a relatively simple cost-effective, and time-efficient manner Thus, various FFQs have been widely employed as a practi­cal instrument since the 1990s FFQs should be developed specifically for each study group and research purposes because diet may be influenced by ethnicity, cul­ture an individual's preference, economic status, etc (11 ] [13 J

I Ỉ.3 Recommended dietary allowance* for elementary school children

The Food and Nutrition Board of the vs National Academy of Sciences de­fines The Recommended Dietary Allowance (RDA) is the average daily dietary in­take level that is sufficient to meet the nutrient requirements of nearly all (97 to 9S percent) healthy individuals in a specific life stage and gender group The RDA is intended primarily for use as a goal for daily intake by individuate [ 18)

J J.3./ Requirements of energy, proteins, fat and carbohydrates

Children need energy on a daily basis for basic metabolism, physical activity, cell development and lifespan Food is an energy- source The three main macronu­trients in the body are carbohydrates proteins, and lipids The kilocalorie is the unit for measuring energy purity (Kcal) (1$] Primary- school children aged 6 to 11 years

old according to the National Institute of Nutrition need betwean 1270 and 2400 Kcal per day to meet their body's growth and development (19)

Protein has been described as the most crucial material or factor in the creation

of life Protein assists in the creation maintenance, and repair of body tissues It is especially important for a child’s growth Meat fish, poultry, milk, and milk prod­ucts are all good sources of protein for children Protein requirements depending on age gender physiological status and medical issue Protein RDAs for elementary school children range from 33 to 50 grams per person per day Protein can account for 20-30% of dietary energy at this age with animal protein accounting for 50% of that [10], [20]

Lipid is a common organic compound present in plant and animal cells It can

be found in butter fat oil milk, meat and other foods Lipid is known to be an im­portant component of food It provides more than twice the amount of energy as protein and carbohydrates (about 9 kcal I gram of lipids) Furthermore, lipid is a carrier of lipid-soluble nutrients including vitamin A DEX The body's ability to absorb lipids detemrines the biological value of fat-soluble substances According

to the RDA for Vietnamese the lipid requirement for children aged (Ho 11 years is 52-72gpei person per day with lipids conn ibuting for 20-30% of total energy Ara­chidonic acid, a poly - unsaturated fatty acid found in animal fat is essential for the rapidly developing children’s body, so the ratio between animal lipids and vegetable lipids is recommended at 70% and 30% respectively [19] [20]

Carbohydrate which includes staple foods sugars and fiber, are the most es­sential ingredient accounting for the majority of meal voltme It is also the body's maul source of energy (1 gram of carbohydrates prorides 4 kcal> The body’s main energy supply 1$ food Carbohydrates contribute to shaping and controlling body movements, as well as being a source of fiber According to the RDAs for Vi­etnamese primary’ school children’s carbohydrate requirement ranges from 210 to

J.Ỉ.3.1 Requirements of vitamins and minerals

Vitamins and minerals are considered important for the growth of children In research all over the world calcium and vitamin D in particular have been shown

to play an important role in the bone healdi and physical development of children at this age (21) Rickets, growth restriction, and stunting axe all symptoms of calcium and vitamin D deficiency in children (22Ị Long-term lack of calcium and vitamin D results in decreased peak bone mass and osteoporosis in adults and the elderly Pre­puberty according to some studies, is a time in the life cycle where the body has very high calcium and vitamin D needs and reacts well to treatments so it has a rea­sonable chance of "repairing" and effectively interfering with bone structural defi­ciencies [23] [23], [24] Thus, pre-pubertv is an important period to intervene in improving bone quality which contrbutes to the formation and maintenance of a strong skeleton in the future and improves children!* heigh1

The mineral phosphorus (P) is the second most abundant in the human body Phosphorus is necessary for the formation and maintenance of strong bones and teeth, as well as the maintenance of body functions [19] [20]

The increased physiological need for physical development in growing chil­dren is a significant factor influencing won status Iron and protein combine to cre­ate hemoglobin in the bodv prevent anemia and increase blood volume quickly dur­ing development Iron absorption depends on the existence of certain substances that increase or interfere with iron absorption Vitamin c animal protein and organ

ic acids in fruits and vegetables work to increase iron absorptioo Iron absorption inhibitors arc commonly found in plant-based foods such as phytate in rice and ce­reals tannins in some vegetables, teas, and coffee [20]

Zinc helps the body metabolize energy, form body organs helps children eat and develop well Zinc deficiency causes children to grow slowly, reduce their re­

sis lance and easily gel infections Selenium is an antioxidant nutrient involved in the regulation of thyroid hormone activity and the redox state of vitamin c and oth

er molecules (19] [20]

A number of other vitamins are also essential Vitamin A is a fat-soluble vita­min that assists in the protection of the eves the prevention of night blindness the normal development of bones and teeth the protection of mucous membranes and skin, and die strengthening of the body’s immunity When children reach school age a lack of vitamin A may have an effect on their intellectual development Vit­amin E is yellow in color, soluble in fat-soluble solutions stable in an acid envi­ronment unstable in the base environment slowly oxidized so it has the main role

of antioxidant Vitamin K functions primarily as a coenzyme in the synthesis of ac­tive proteins involved in blood coagulation Vitamin c helps absorb and use iron, calcium folic acid anti-allergic increase immunity, anti-oxidant [19], [20]

Vitamin Bl is ven’ important Lack of vitamin Bl leads to disorders of car bohydrate and amino acid metabolism, causing serious consequences such as affect­ing the functico of the nervous system, causing loss of appetite decreased appetite, and decreased muscle tone vitamin B2 is part of the group of enzymes that break down and utilize carbohydrates proteins and lipids It is essentia] for reproductive growth and for eyes skin hair and nails Vitamin pp (niacin) is necessary for the synthesis of proteins lipids and the creation of DNA andRNA Niacin is particular­

ly important for the functioning of the nervous system and it is also required for the synthesis of sex hormones Vitamin Bl 2 helps to create red blood cells keeps the digestive system and nervous system working well plays a main role in metabolism (19] U0]

1.2 Ph) steal acthlty

Lĩ.i Dt/biỉtiơn ữf physical activity

Physical activity is defined as "bodily movement that is produced by the con- Uaction of skeletal muscle and that substantially increases energy expenditure' [25]

This term therefore includes the full range of human movement from competitive sport and exercise to hobbies or activities involved in daily living Conversely physical inactiviy can be described as "a state in which bodily movement IS mini­mal and energy expenditure approximates the resting metabolic rate" [26]

Physical activity is a complex, multi- dimensional behavior Many different modes of activity contribute to total physical activity, these include occupational household (e f caregiving domestic cleaning) transport (e.g walking or cycling to work) and leisure* time activities (cf dancing swimming) Exercise is a subcate­gory of leisure- time physical activity and is defined as physical activity in which planned, structured and repetitive bodily movements are performed to improve or maintain one or more components of physical fitness” [26] [27]

Physical activity can be classified further according to its frequency, dura­tion and intensity The frequency and duration of an activity refer to bow frequently and for how long it is done The amount of energy expenditure that an activity nec­essarily requires is referred to as intensity [26]

Physical activity is a multifaceted behavior that can be assessed in a range of methods For measunng energy expenditure and more precisely, physical activity', a variety of instruments are available including objective and self-reporting methods Both physical activity and inactivity (sedentary behavior such as sitting or televi­sion viewing) can be measured using these methods [26], [28]

Self-Report Questionnaires

These questionnaires are the most common method of PA assessment [29] and rely on participants' recall ability Questionnaires vary by what they measure (eg mode duration or frequency of PA), how data are reported (eg activity scores time calories), quality of the data (eg measures of intensity, differentiating between habitual and merely recenr activities inclusion of leisure and non-leisure

activity), and how data are obtained (e g paper and pencil assessment computer­ized questionnaire, interview) (30)

Their advantages include cost effectiveness ease of administration and ac­curacy in measuring intense activity, determining discrete categories of activity lev­

el (e g , low moderate, high), ranking individuals or groups in their PA providing details about the PA and showing improvement across groups ox individuals Po­tential disadvantages are that self-report questionnaires are less robust in measuring light or moderate activity, assessing energy expenditure and may be limited by the dependency on written language (j.e questions) and external factors (i.e social de­sirability complexity of the questionnaire age and seasonal variation) Self-report questionnaires are significantly more reliable at die group than the individual lev­

el as well as when the questionnaire is structured chronologic ally and with discrete periods [26] [28] [31]

Self Report Activity Diaries Logs

Self report diaries require participants to record PA in real time which pro vides the most detailed data and can overcome some limitations of questionnaires (j e less susceptible to recall errors social desirabilitv bias measurement bias) To illustrate Bouchard's Physical Activity Record (BAR) 1$ a widely used diary in which participants report PA for each 15-minute interval ova three days Activities axe rated on a scale of 1 to 9 (1 = sedentary activity 9 a intense manual work or high intensity sports) to yield a total energy expenditure score however the diary is burdensome particularly for individuals with cognitive dysfunction In addition questionnaires not completed in real time could be subject to memory bias as well

as participant reactivity the phenomenon of behavior chaqge due to awareness of being observed [28] [30]

Objective methods [28]

Direct Observation

In direct observation an independent observer moniicn and records Pa

This method of assessment is often used when activity is restricted to a delineated space (e g a classroom) It is also a popular method for >oung children as they have difficulty recalling their PA This flexible method is valuable in gathering con­textual information (e g preferred location time and clothing) and details of the

PA (e g type personalized variations to activities) Disadvantages include high cost of time and energy, potential reactivity difficulty obtairuag ethical approval, and the lack of objective measures of energy expenditure

Devices: Áccelcromeiers

In recent decades, accelerometers have gained popularity given their accura­

cy ability to capture large amounts of data, and ease of administration particularly

in large studies Accelerometers measure acceleration (counts) in real time and de­lect movement in up to three orthogonal planes (anteroposterior mediolateraL and vertical) These counts are then translated into a metric of interest, which can be bi­ological (e g energy expenditure) or PA p3ttems (e g stationary) Devices can be worn in numerous places on the body, including waist, hip and thigh

Devices: Pcdonietcrs

Pedometers measure the number of steps taken with a horizontal spring- suspended lever amt which is deflected when the subject's hip accelerates vertically with a force beyond a chosen threshold Pedometers correlate strongly with uniaxial accelerometers and directly observed duration of activities Their simplicity rela­tively low cost and ability to pick up short durations of PA (often missed by self­report measures) make these dev ices popular Pedometer data also tend to be corre­lated with biological outcomes and predictors (e g age BXfl) Pedoneters appear to yield the most accurate data for running and moderate walking, as these behaviors require forward vertical motion

Devices: Heart-Rate Monitors

He lit rate monitoring is a physiological indicator of Pa and energy expend hire providing real-time data on the frequency, duration and intensity of PA in an unobtrusive (eg they can be worn as watches or on the chest) low-effort way for periods up to one month HR monitors capture energy expenditure during activities not involving vertical trunk displacement that many accelerometers and pedometers miss and arc best suited to categorize subjects' PA levels (i.c highly active, some­what active, sedentary) as opposed to the exact amount of PA These devices tend to show discrepancies particularly at very high and low intensities

Tor school-aged children physical activity can be undertaken as part of rec­reation and leisure (play, games, sports or planned exercise), physical education, transportation (wheeling walking and cycling) or household chores, in the context

of educational home and community settings Physical activity improves physical fitness (cardiorespiratory and muscular fitness), cardiometabolic health (blood pres­sure dyslipidemia glucose, and insulin resistance), bone health, cognitive results (academic success, executive function) mental health (depression symptoms re­duced) and adiposity reduction tn children (6] (32 J

According to WHO guidelines on physical activity and sedentary behavior (6J It is recommended that;

- Children and adolescents should do at least an average of 60 minutes per day

of moderate- to vigorous-intensity, mostly aerobic physical activity, across the week

Vigorous intensity aerobic activities as well as those that strengthen muscle and bone, should be incorporated at least 3 days a week

WHO also recommended about sedentary behavior which is defined as time spent sitting or lying with low energy expenditure while awake, in the context of educational, home and community settings and ưansportation It is recommended that; Children and adolescents should limit the amount of time spent being seden

tan* particularly the amount of recreational screen time Strong recommendation low certainty evidence [6 I

In the US 2018 U.S Department of Health and Human Services published 2nd edition of Physical Activity Guidelines for Americans (33), including Key Guidelines for School-Aged Children and Adolescents

* It is important to provide young people opportunities and encouragement to participate in phvsical activities that are appropriate for their age that are en­joyable and that offer variety

- Children and adolescents ages 6 through 17 years should do 60 minutes (1 hour) or more of moderate-to-vigor OUS physical activity daily

• Aerobic: Most of the 60 minutes or more per day’ should be either moderate- or vigorous-intensity aerobic physical activity and should include vigorous-intensity physical activity on at least 3 days a week

• Muscle-strengthening As part of their 60 minutes or more of daily physical activity, children and adolescents should include muscle­strengthening physical activity on at least 3 days a week

• Bone-Strength win g As part of their 60 minutes or more of daily physical activity children and adolescents should include bone-strengthening

physical activity on at least Ĩ days a week 118].

In Vietnam, the physical activity recommendations for students follow WHO guidelines Besides, children should not exercise for more than 2 hours a day; in­stead children should be involved for 30 minutes a day at first and gradually in­crease their time There are no conprehensjve studies or specific guidelines for Vi­etnamese people Physical activities just stop at health education communication activities

1.3 Previous studies on dletan* Intake and physical activity of elementary school children

I.

J.1 ỉn rite world

Study on Dietary intake

A Stud}' examined differences between school hour and non school-hour di­etary intakes of school-hour diet quality among Canadian children Children report­

ed consuming, on average 746 kcal during school hours (one-third of their daily energy intakes) Vitamins A D B12 calcium, and daily products densities were at least 20% lower during school hours compared with non school hours [34]

In Malaysia a study of BK Poh showed that dietary intake of the children was not compatible with the recommendations where more than one-third did not achieve the Malaysian RNI for energy, Ca and vitamin D The present study re­vealed that overnutrition was more prevalent than undernuưiúoa The presence of high prevalence of vitamin D insufficiency and the inadequate intake of Ca and vit­amin DaTC of concern (35]

Another study conducted in Thai urban and rural area showed that protein in­takes of all age groups were relatively high in both the areas Intakes of Ca, Fe, Zn and vitamin c were significantly higher in urban areas than in rural areas The prev­alence of anemia in rural areas was twice as high as that in urban areas particularly

in infants and young children However the prevalence of Fe-deficiency anemia was sunilar in both urban and rural areas While the prevalence of vitamin A defi- ciency (by serum retinol cut-off <0'7 11 mold) seemed IO be very low vitamin A in­sufficiency (by serum retinol cut-off < I 05 pmol/1) was more prevalent (29 4-

31 7%) in both the areas The prevalence of vitamin D insufficiency ranged be­tween 27 7 and 45 6% among the children (361

In Indonesia, a similar study found that he percentage of children with die­tary* intakes of energy, protein, and Vitamins A and c below the Indonesian RDA was high and differed across urban and rural areas and age groups (J7).

Study on PA

Several researches have been conducted around the world to assess elemen­tary* school students' physical activity' The study conducted by Zimmo L et al., in 201" showed that only 39% of primary school students in Qatar engaged in moder­ate to vigorous physical activity for 30 minutes or more a day Students spend on average of 58 1 ± $.4% of school time on sedentary activities Moderate to vigorous physical activity of boys and girls was similar in age 5 while girls age 9 were less active (23.7 ±1.5 min dav) than bovs of the same age (42.7 = 1 8 min day), ES “ 0.269 p < 0.001 Neither overweight children nor children at risk for being over­weight showed any differences in physical activity parameters when compared to children of normal weight Our results showed, percentage of MVPA on the first (7.7 X 5.1%) and last (7.1 X 4.1%) days of the week was generally lower compared

to other weekdays (P < 0.001) [9j

Another research conducted by Yli-piipari s et al in over 200 children aged

6 to 8 years old in the United States and Finland found that on an average school day students were engaged in MV PA for 20 0 min in the US and 24.1 min in Fin­land Students* school-dav MVPA was 9 to 16 minutes higher during physical edu­cation (PE) days compared with non-PE days (U s 25 8 vs 16 6 min day Finland 36.3 vs 20 1 min day) Girls had less MVPA and more sedentary time compared with boys in both samples (38J

Research by Diouf et al conducted in primary school students in Dakar - Senegal showed that PAQ results were comparable in the 156 and 42 pupils The 42 pupils presented a light activity measured by accelerometer while PAQ classified the majority of them (57%; n = 24) in the moderate PA level Children spent most

of their lime (min day) in sedentary activities and light activities than in moderate

and intense activity levels Accumulation of 60 min day Mo derate-to-Vigorous Physical Activity (MVPA) was achieved by 54 8% (n ■ 23) of the pupils MVPA decreased in girls in relation to their body fatness There was a significant differ­ence in MVPA between boys and girls Similarly, overweight obese (45 X 16 min day) children had lower MVPA than their normal and underweight peers (88 X

34 and 74 ± 36 min day, respectively p = 0 004) [39Ị

A research conducted in school children in West Java Indonesia in 2016 shows that average duration of underweight subjects performing sedentary activities

on holidays was 4.2=3 0 hours 5.4=2 7 hours for normal subjects 5 s=2 7 hours for overweight and 5.4x2.5 hours for obese subjects The proportion of sedentary ac­tivity time on holiday among underweight normal overweight and obese subjects were 17.6=12.4%; 22.3=11% 24.1=11 3% and 22.3=10.5% The sedentary activity

of children on holiday was not significantly different but there was a significant difference between the proportxii of sedentary time in a day between groups of nu­tritional status (p>0.05) [40 J

Ĩ.Ỉ.2 /n I'irrnam

Study on Dietary intake

Research by Vu Quynh Hoa and colleagues on students of two primary schools in Ho Chi Minh City in 2014 showed that the average child's daily food consumption was 231 9 = 76 8g of cereals 172.6 s 114 5g of vegetables 96 2 = 126.7g of fruit and 132 7 = 10S.5gof meat The average energy consumption is

1684 I = 46O.4kcal The energy structure is p L c=16929.4 53 7 The structure is not balanced lipids and proteins account for a high proportion in the diet (41)

A study by Tran Khanh Van et al in 2017 conducted in Thai Nguyen prov­ince found that the dietary intake of elementary school students aged 7 to 10 years did not meet the recommended dietary allowances of the National In stimte of Nutri­tion in terms of both energy and structure of macronutrients Lack of micronutrients

in the diet [4]

study on PA

There haven’t been many studies in Vietnam that evaluate primary' school students’ physical activity Cunent research has focused mostly on adolescents and adults In 2016 Do Van Dung et al conducted a study on 619 grade 5 students from eight primary schools in Ho Chi Minh City finding that 18% of students did not engage in physical activity the average number of steps per day was 8800 male students are more active than female students, students are more physically active

on weekdays than on weekends and sedentary activities are common in both gen­ders 110Ị

CHAPTER 2: BESE ARCH SUBJECTS AND METHODOLOGY

2.1 Study subjects:

Students of elementary- school in Ha Nam and Dien B-.en provinces

2.1.1 Inclusion criteria:

• Family (caregiver) voluntarily agrees and signs a commitment to participate in the study

2.1.2 Exclusion criteria:

■ Children were away, absent during the study period

• Children with physical and mental deformities affectinganthropometric

• Family (caregiver) with a mental illness could not be interviewed

Family (caregiver) did not voluntarily agree to participate in the study

- Study time: from August 2020 to April 2021

Survey lime, from October 2020 to February 2021

• n Number of sample (subjects)

• Z|.»3 The critical value of the normal distribution al 0/2 (is 1.96 with a confidence level of 95% and a = 0.05)

previous research (= 484 kcal according to result of a research by Ngo Thi Xuan in Bac Ninh province in 2020 [42J)

- ử Estimated error between sample and population(=70)

From the formula the minimum overall sample sire IS 192 students

In practice 225 students were taken to be interviewed 24-hours dietary recall.Sample size for physical activity: Using sample size formula for estimating

an average value to calculate the ỊÌivsical activity sample size

n=2<’-'í’(fõĩ

ỉl"ow

• Zl-a.2 The critical value of the normal distribution at (l '2 (is 1.96 with a

confidence level of 95% and a - 0.05)

- e: The expected relative error (»0.05)

study of Diouf et al (391)

mg to the study of Diouf el al [39])

From the formula the sample size in physical activity is 190 By adding 10% participants who refused to take part in study, the minimum sample size is219

In fact 248 students involved in the research to be interviewed physical activ­ity by PAQ questionnaire

2.3.2.2 Sampling method:

Using multi stage sampling method:

Province selection purposively select two provinces (Ha Nam And Dien Bien)

• School selection randomly select 3 school each province

• In Ha Nam province: Thi Son Primary School Kim Bang District Nguyen

Lv Primary School andHoa Hau Primary School - Ly Nban District

• In Dien Bien province Ta Sin Thang Primary School Tua Chua District

Na N’han Primary School and Nong u Primary School Dien Bien Phu City

to 10 Randomly select a target sample of 10 students per age group in each school Simultaneously collecting the information about dietJQ- intake and phys­ical activity of each student

23 Variables and indicators

Group of general variables:

Group* of variable* and indicator* and dietary indicators:

Average consumption of food according to 14 food groups speciSed in the Vi­etnam Food Composition Table 2007 [43]

- Nutritional value of the diet (calories of foe diet, macronutrients of the diet, value of vitamins and minerals in the diet)

• The level of energy and micronutrient requirements of the diet to be met (compared with the recommended dietary allowances of Vietnamese people in 2016) [19]

Group of variables and indicators on physical activity ưatus:

Level of PA clasiified according to the cut off score of Kowalski LC et al (44]

Frequency of students engaging in MVPA at least 60 minutes day in the past 7 days

■ Frequency of students participating in sports activities during the past 7 das's

• Activities the students do during most school breaks

Transportation to school of students

• Average time students participate in sedentary activities

• Electtonic devices students use most often

- Average sleep time of students at night

2.4 Data collection

- Distribute the designed questionnaires to the parents (caregivera) of the Stu dents in order to collect data

• Data collection tools methods and measurements

Measuring dietary intake:

Single day 24-hours dietan- recall was used to interview parents (caregivers) of the students about their dietar intake We also used photo album provided by the National Institute of Nutrition for supporting parents (caregivers) to recall and de­scribe correctly the size of intake

After the interview food was converted into actual consumption (take the amount of clean raw food minus the waste amount of each type of food specified in the Vietnam Food Composition Table) Then, the nutritional composition of each food was calculated according to the Vietnam Food Composition Table [43]) Measuring the level of requữemeut response and the balaore of the diet according

to the RD As for Vietnamese people 2016 of NIN [19]

Measuring physical activity or students:

Parents (caregivers) were interviewed about characteristics of physical activity and sedentary activity of students in the past 7 days by physical activity' question­naire age specific validated and applied in Vietnam [45]

The questionnaire measures general physical activity levels in children aged 7

- 12 years during a typical week in a school year The questionnaire includes 9 questions (from question 3 to question 11 in appendix) based on a broad spectrum

of activities taking place during physical education, school bleaks, days and eve­nings and over the weekend All nine questions were scored on a 5-point Likert scale assessing frequencv and intensitv of activities Children were categorized as having low moderate or high physical activity based on their final mean score (PAQ score) A score of 1 00 - 2 35 indicated low physical activity a score of 2 34 -

activity was taken as a score between 3.6“ and 5 00 [44J

2.5 Potential tri ors and solations

2-f.l- Potential errors

consumed or activities that were not actually do

• From data collecting method: 24-hour dietary recall with one day could not cover the variety of food intake depending on subjects' memory

■ From data screening process identifying food compositions changing nutrient content occurring during food storage and preparation mistaken in entering varia­bles analysis database

2.5.2 So/M/jo/n

- From interviewers understand the questionnaire, be trailed carefully about the investigational methods and questionnaire

From data collecting and screening thoroughly monitor and recheck the data

at the collecting area and before screening

Simple processing of information from the questionnaire was required before entering data into the software

Epidata 3 1 was used to enter all variables data of general information STATA version 14 0 was used for data analysis Data screening was done before analyzing the data

2.7 Ethical issues

The protocol was approved by the NIN Ethical Committee before the survey

only by researchers All information has been used only for research purposes

C’HAPTE R 3: RESULTS3.1 Characteristics or research subjects

Table 3 I De/nograpilic characteristics of the students

In terms of ethnic distribution, the Kinh people account for more than other ethnic groups 54% and 46% respectively However, there are differences in ethnic distribution between the two provinces Jn Ha Nam 100% of the students are Kinh while 97 4% of the students in Dien Bien axe ethnic minorities (including Thai Mong Hoa)

3.2 Dietin' intake of research subjects

Table 3 2 Food contumpfion of ifiulenif by province

Food group

Ha Nam (D-13C)

Dien Bien

Cereals and their

Meat and meat

meat products (106.9 X 94 7g) milk and their products (16.8 X 27 9g) vegetables and their products (84 s X 76.9g), fruits and their products (61.7 * 98 5g)

Students in Ha Nam had the average consumption of cereals, meat, eggs milk and fruits, respectively 257 7 X 133 Ig, 130 4 X 100 6g 19 9 = 29 5g 1304 X

136 6g 79 6 X 109 lg This intake was higher than that of students in Dicn Bien (224.0 = 98 2g 74 8 = 75.5g 12 6 = 25 1.29 3 = 89 6g 37 2 = 75.5g respectively) These differences are statistically significant with p <0.05 (Mann-Whitney test) In contrast students in Dien Bien consumed more seeds and nuts than in Ha Nam (21.6 = 51.7g and 7.4 = 23.lg respectively) The difference is statistically signifi­cant with p <0.01 (Mann-Whitney test)

Table 3 3 Energy anti marronuirlenn Intake by province

Ha Nam (■=130)

Dlen Bien(■=95)

"Manrt- fThitney test

The table above shows the value of macronutrients in the diets of students by province The mean energy of students in two provinces is 1367 6x568 1 Kcal To­tal proteins, lipids and carbohydrates were 56 4 ± 27.1g, 37.4 = 29.9g 201 9 = 93.4g respectively In Ha Nam province the value of energy and macronutrients

axe higher than in Dien Bien The average energv total protein, total lipids and car

•45.8 = 33.7g 217.3 = 102.0g, respectively Meanwhile in Dien Bien, these indexes are 1134.7 = 413.9 kcal 43.8 X 19.5g 25 9 ± 18 2g 180 9 X 75.7 g respectively The difference is statistic ally significant with p<0.01 (Mann-Whitney test)

íable Ẳ 4 Micronutrients intake of the students by prow nee

Minerals and

vitamins

Ha Nam (nlJO)

Dicn Bien (■=95)

Regarding vitamins in the diet, vitamin c and B vitamins in the diets of Ha Nam students are mostly higher than in Dien Bien Particularly the amount of fo­late ofDien Bien is higher (132 1 X 109.0mcg in Ha Nara and 184.1 X 142 5mcg in Dien Bien) Vitamin A in the diets of Ha Nam students is higher than in Dien Bien (376.0 = 657.2 mcg and 1616= 187.7 mcg respectively), although the amount of beta carotene m the diets of students in Dien Bien was higher (2259 5 X 3281.7 mcg

in Ha Nam and 3980.8 X 4286.5 mcg in Dien Bien) The amount of vitamin D in the diet of Ha Nam students is 4 times higher than that of Diet! Bien (1 6 = 1.8 mcg and

0 4 X 0 9 mcg respectively) In addition vitamin E and K levels of Dien Bien stu­dents are higher than those of Ha Nam students (2-2 ± 1.6 mg and 304.5 * 344.“mg

in Dien Bien 18x1 6mg and 150 7 X 255 4mg in Ha Nam respectively) Except

for vitamin c and lycopene there are statistically significant differences between the two provinces in the remaining indices w ith p<0 05 (Mann-Whitney test)

Figure 3 J Proportion of energy aná macromarients meeting RD A by province.

Figure 3.5 describes the proportion of students achieving the RDA in energy and energy substances by province According to the figure students in both prov­inces are not meeting the recommended energy levels (87% of the RDA in Ha Nam and 65% of the RDA in Dien Bien) Protein consumption tn both provinces is high (168% of the RDA in Ha Nam and lilt* of the RDA in Dien Bien) Meanwhile carbohydrate consumption in both provinces is low (92% of the RDA in Ha Nam and 78% of the RDA in Dien Bien) There is a difference between lipid consump­tion in the two provinces The ratio of lipid consumption to RDA in Ha Nam is 117%, while in Dien Bien it is only 67%

ODte^B-e* QToul

Figure 3 2 Proportion of micro nutrient* meeting the RDA by province.

Figures 3.5 shows the proportion of micronutrients meeting the RDA by province According to the chart, only phosphorous, iron zinc, copper, vitamin c vitamin pp vitamin B5 and vitamin B12 in the studenrs diet met the RDA The re­maining micronutrients were under the RDA There were a significant difference between the amounts of calcium, vitamins Bl pp Bl2 A and D between the two provinces The proportion of micronutrient deficiency compared to the RDA in Dien Bien were higher than in Ha Nam