Evidence of the Short- and Long-term Effects of a Residential Stay in a Danish Christmas Seal Home - With and Without a High-intensity Activity/Health Education (FIFA 11 for Health) Programme.
Phase: NA
Conditions: Overweight
Sponsor: University of Southern Denmark

Protocol – Danish Christmas Seal Houses, HIHE 
 
 
 
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Short- and Long-term Health Effects of a Residential Stay in a Danish Christmas Seal Home. 
16-12-2019 
 
 
 

Protocol – Danish Christmas Seal Houses, HIHE 
 
 
 
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PROTOCOL 
 
Title: EVIDENSE of the effort on the Danish Christmas Seal Houses: Short and long-term effects 
on health status, physical fitness, physical activity level, learning, sleep and well-being for 
children on Danish Christmas Seal Houses – with and without a high intensity activity/health 
education program.  
 
The study is collaboration between Institute of Sports and Biomechanics, Faculty of Health Science, 
University of Southern Denmark, Institute of Nutrition, Exercise and Sport, University of Copenhagen 
and the Danish Christmas Seal Houses (Julemærkefonden).    
 
Principal Investigator:  
Professor Peter Krustrup, University of Southern Denmark  
Department of Sport Science and Clinical Biomechanics, Unit of Sport and Health  
Campusvej 55, 5230 Odense M 
Tlf: 21 16 15 30 
E-mail: pkrustrup@health.sdu.dk 
 
Collaborators: 
Professor Kim F. Michaelsen, University of Copenhagen 
Department of Nutrition, Exercise and Sports 
Rolighedsvej 26, 1958 Frederiksberg C 
 
Professor Anders Sjödin, University of Copenhagen 
Department of Nutrition, Exercise and Sports 
Rolighedsvej 26, 1958 Frederiksberg C 
 
Adjunkt Mads Fiil Hjort, University of Copenhagen 
Department of Nutrition, Exercise and Sports 
Rolighedsvej 26, 1958 Frederiksberg C 

Protocol – Danish Christmas Seal Houses, HIHE 
 
 
 
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Postdoc Malte Nejst Larsen, University of Southern Denmark  
Department of Sport Science and Clinical Biomechanics, Unit of Sport and Health  
Campusvej 55, 5230 Odense M 
 
 
Scientific associate Trine Kjeldgaard Møller, University of Southern Denmark  
Department of Sport Science and Clinical Biomechanics, Unit of Sport and Health  
Campusvej 55, 5230 Odense M 
 
 
 
 
 
 
 
 

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Aim 
 
The aim of the project is to document the short-term effects on health, physical fitness, physical 
activity level, learning, sleep and well-being from a 10 weeks residential stay on one of the Danish 
Christmas Seal Houses. Furthermore, to document the long-term effects 3 and 12 months after the 
stay.  In addition, the project examines if a special effort with a high intensity activity/health education 
program (HIHE) increases the effects on physical fitness and health knowledge, learning capabilities, 
sleep patterns, well-being and adherence to a physical active lifestyle compared to the standard 
program.    
 
Theoretical background  
 
Physical activity and health 
Physical inactivity and childhood obesity is connected to risk factors for cardiovascular disease 
(Tremblay et al. 2011, Han et al. 2010, Nadeau et al. 2011, Andersen et al. 2006). Because low aerobic 
fitness and obesity in childhood most likely extends into the adult life, this is a worldwide concern 
(Trudeau et al. 2003, Reilly 2006). Habits and attitudes about physical activity are shaped during 
childhood (Malina 1996, Kristensen et al. 2008), and the Body Mass Index (BMI) of childhood is directly 
correlated with the risk of cardio vascular (CV) disease later in life (Baker et al. 2007). 
 
In Denmark, 21% of the girls and 15% of the boys are overweight because of lifestyle and lack of 
physical activity (Pearson et al. 2005). Research has shown that the overall health and physical fitness 
in Danish school children has worsened over the resent years (Wedderkopp et al. 2004, Ekeland et al. 
1999, Rasmussen, Due & Holstein 2000). From 1998-2007 the proportion of children in school age, 
who regularly do sports or exercise, dropped from 89% to 84%, including a drop from 93% to 88% 
among the 10-12 years old children (Pilgaard 2008). Furthermore, there were a reduction in 2006-2010 
in the amount of highly active children (Rasmussen & Due 2010), and the level of daily physical activity 
has become more uneven distributed over the last 20 years. With an increasing amount of children 
who are insufficiently active, as the result (Wedderkopp et al. 2004, Wedderkopp et al. 2001, Ekeland 
et al. 1999).        
 

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A Danish study has shown that the total physical activity volume of Danish girls is lower than that of 
Danish boys, due to a lower activity level in after school programs, where they are less included in 
physical activity such as team sports and ball-games. This results in more girls (30%) than boys (17%) 
who do not reach the recommended level of daily physical activity (Nielsen, Pfister & Andersen 2011). 
The daily physical activity level drops with increasing age (Pearson et al. 2005, Sundhedsstyrelsen 2006, 
Sundhedsstyrelsen 2010, With-Nielsen & Pfister 2011), and an increasing number of Danish 
schoolchildren are inadequate physical active – especially after 10-11 years of age. The age dependent 
drop applies for both organised sport and unorganised physical activity, because fewer 13-15 year-old 
children participate in both organised sport and unorganised physical activity after school in 
comparison to 10-12 year-old children (Pilgaard 2012). Therefore, there are a need for initiatives that 
can increase and maintain the physical activity level of children and young people.         
 
There have been an extensive number of studies, studying the fitness and health profiles of European 
and Danish children (Andersen et al. 2006, Andersen et al. 2008, Bencke et al. 2002, Seabra et al. 2012), 
but most studies have used a cross-sectional design. For instance, a large cross-sectional study showed 
that risk factors of cardio vascular disease accumulated in 15% of Danish children (9-10 year) and 
young people (14-15 year). Accumulation of 4-5 risk factors was positive related to BMI and negatively 
related to fitness level for both genders in these age groups (Andersen et al. 2003, Wedderkopp et al. 
2003). 
 
It is well known that regularly physical activity is connected with significant positive physical and 
mental effects. Physical activity plays an essential role in the prevention of a number of diseases, 
which challenges the modern society (Ebbeling et al. 2002). Studies show, that those children, who are 
regularly involved in activities in sports clubs, have better heart and bone health than children, who 
are not members in the local sports club (Seabra et al. 2012). Studies, that examined measurements of 
aerobic endurance, have found favourable connections between aerobic fitness and systolic- and 
diastolic blood pressure (Ondrak et al. 2007) and arterial stiffness (Boreham et al. 2004). Likewise, a 
study has shown that children, 9-10 years of age, who played recreational football 3x40 minutes a 
week for 10 weeks, enhanced the structural and functional functions of the heart (Krustrup et al. 2014).  
 

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Most physical activity recommendations regarding childhood, including school based activities, focus 
on training duration, e.g. 60 minutes a day (Strong et al. 2005, WHO 2003, UK CMOs report 2011, 
Sundhedsstyrelsen 2005). But newer studies have shown that intense training is more effective for 
adults and young people in relation to improvements of aerobic and anaerobic fitness, compared to 
moderate intensity training (Krustrup et al. 2010a+b, Ingul et al. 2010, Sperlich et al. 2010). Newer 
studies on children, have shown high intensity during recreational football, basketball and unihockey 
(Bendiksen et al. 2012, Randers et al. 2010a), and that recreational football can improve submaxim and 
max physical capacity, motor skills and self-worth in overweight children (Faude et al. 2010). 
Furthermore, studies have shown, that football training improves body perception, self-worth and 
inclination to participate in physical activity (Seabra et al. 2014), and also structural and functional 
effects on the cardio vascular system in overweight children (Hansen et al. 2013).      
 
Scientific reviews concludes, that school interventions with physical activity can be effective in 
improving health status, since these interventions has potential to reach all children, including the 
ones with low fitness, overweight or low bone mineral density, e.g. girls with limited physical activity 
during and after school together with low Ca2+ intake (Van Sluijs et al. 2007, Dobbins et al. 2009). There 
are surprisingly few intervention studies targeting assessments of physical training for children, and 
they have, in general, not shown long term adherence. This complicates interventions and public 
health campaign recommendations (Wilfley et al. 2007, Harris et al. 2009). 
 
A pilot study with”FIFA 11 for Health” in Denmark, was initiated in the 2015/16 school year, with 546 
participating 10-11 year old pupils. The study showed that the”FIFA 11 for Health” program had a 
positive effect on systolic and diastolic blood pressure, BMI and fat percentage in the children (Ørntoft 
et al. 2016). This could indicate a lowered risk for cardio vascular diseases in the adult life (Baker et al. 
2007, Andersen et al. 2003, 2006 and 2011). Furthermore, the pilot study examined the well-being of 
the pupils. The results showed a significant positive effect in regard of social well-being, among those 
pupils that completed the ”FIFA 11 for Health” program, but no change among the pupils who 
participated in the regular school program (Fuller et al. 2016). Additionally, the study showed an 11.9% 
improvement in health knowledge, and 72.4% of the participating children had a positive experience 
with the program, and only 4.8% had a negative experience (Fuller et al. 2016). 
 

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Cognitive functions 
The connection between physical activity and cognitive functions has been examined by several 
studies. The focus has mainly been on the executive functions, which cover the cognitive processes 
that are responsible for problem solving and goal orientated action (Diamond 2006, Hillman et al. 
2008). Especially the coupling between the fitness level and cognitive functions in children have been 
examined, and several cross-sectional studies on school children have found positive associations 
between the children’s physical fitness and cognitive (Chaddock et al. 2012) and academic 
performance (Hillman et al. 2008). Recently, similar findings have been found with Danish children, 
and on top of that, it has been shown that children who participate in sports club activities perform 
better in cognitive tests and reading (Geertsen et al. 2016). Other cross-sectional studies have related 
these associations to structural differences in the nerve system, where children with high fitness levels 
have a larger volume in some of the central brain structures, i.e. memory, than children with low 
fitness levels (Chaddock et al. 2011, 2010, Pontifex et al. 2011). Although these correlations does not 
explain causality, the positive connections are confirmed by several intervention studies with physical 
activity, which have shown positive effects on i.e. cognitive functions (Chaddock-Heyman et al. 2013, 
Davis et al. 2007, Hillman et al. 2014). It seems like the type of physical activity is of importance for the 
effect on cognition. Among others, Pontifex and colleagues (2009) found, that the effect on cognition 
was specific for aerobic training rather than strengths training (Pontifex et al. 2009). In addition, a new 
study has shown that the intensity of the physical activity is significant for cognitive functions such as 
motor skill processing (Thomas et al. 2016). Moreover, studies have shown that fine and gross motor 
skills were positively associated with cognitive functions in children (Geertsen et al. 2016). In relation 
to this, it will be interesting to measure if ball games (such as football), which consist of a high amount 
of coordinating complex physical movements, strategy and goal oriented actions (Pesce et al. 2009), 
can develop the cognitive functions in children, in particular the development in executive functions 
(Best 2010). Simultaneously, it is an area with great political attention in relation to the new Danish 
reform for the primary and lower secondary school, where children 6-16 years of age is active 45 
minutes a day during school hours. In spite of many earlier studies, there is a lack of knowledge about 
whether or not programs like ” FIFA 11 for Health” is capable of implementation, and if the 
characteristics of the programs can influence not only health and social factors, but also cognitive 
functions, including brain activity, in children. 
 

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Hypothesis  
This project incorporates recreational football and health-knowledge. A pilot study has shown positive 
effects on blood pressure, BMI and fat percentage in children (Ørntoft et al. 2016), and there are 
comprehensive evidence about the positive cardio vascular (Krustrup et al. 2009, 2013), metabolic (De 
Sousa et al. 2014) and muscular-skeletal effects (Krustrup et al. 2010c, Helge et al. 2010, Oja et al. 
2015) of football for adults. Furthermore, the pilot study showed increased health-knowledge and 
school related well-being among the participating pupils.  
Thus, the hypothesis is that a 10-week residential stay at the Danish Christmas Seal Houses (DCSH) has 
positive effects on general health, physical fitness, learning, sleep patterns and well-being. 
Furthermore, the HIHE program (“FIFA 11 for Health program – health-knowledge on the football 
pitch”) will result in larger improvements on health, physical fitness sleep patterns, well-being and 
adherence to a physical active lifestyle than the standard program in DCSH.   
 
Participants, inclusions- and exclusions criteria 
There are 24-48 children on each of the DCSH. They have a continuously admission of children in the 
age range 7-14 years, and every child is offered a 10 weeks residential stay. From september 2018 
about 600 children (boys and girls) will be recruited from two DCSH.  
Inclusions criteria: 
• Boys and girls in a 10-week residential stay at the DCSH in the age of 7-14 year. 
• Informed consent from parents/legal guardian. 
• Willingness to participate in training and tests. 
 
Exclusions criteria: 
• Participants, of which the scientists do not find, suited to follow the procedures of the protocol 
and the program for training and testing. 
 
Participants can at all times choose to with-draw from tests, if this is desired or necessary due to illness 
or injury. All children at the DCSH participate in the training as part of the scheduled program.  
The specific reasons to include individuals, who cannot give informed consent, are group C, cf. Comity 
law §19: “That the project can only be completed by including individuals, whom are in the specific age 

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group, illness or condition, and that the project have a direct possibility to transfer large positive 
advantages to the patient population that consist of the same age group, illness or condition as the 
participant, and that the project involve minimal risk and inconvenience for the child or the young 
participant”. The project can give valuable information on health-related training effects and form the 
foundation for physical activity recommendations for overweight children in Denmark. The project is 
also useful for any specific participant, as participants and parents, besides for the training, achieve 
knowledge about physical capacity and health. Furthermore, there are minimal risks for the participant 
in relation to the tests, measurements and training.   
Statistic and power calculation 
The primary outcome of the project is fat percentage, and among the most important secondary 
outcomes are aerobic fitness, health-knowledge and well-being. The power calculation is based on the 
result of the pilot project (Ørntoft et al. 2016). The power calculation is measured with t-test. Some 
variables are expressed in table below and are based on the development on variables from the pilot 
study and a study with children from the same age group as on the DCSH (Bendiksen et al. 2014). The 
calculations are based on a power of 0.80 and p-value of 0.05. 
 
 
Calculation of number of participants (N) in relation to the evaluation on the DCSH 
standard program and the assessment of activity and health-program (HIHE).  
Power calculation 
Intervention 
group 
(HIHE) 
Standard group 
IG vs SG 
Delta 
IG 
SG 
Sample size 
Fat percentage, 
intervention period 
Fat percentage, follow-
up period 
Aerobic fitness 
Health-knowledge 
Muscle mass 
-9.6 (4.2) 
 
5.0 (13.4) 
 
148 (63) 
11.9 (23.5) 
0.6 (0.7) 
-8.9 (3.7) 
 
8.4 (12.9) 
 
-106 (83) 
2.6 (23.7) 
0.5 (0.9) 
-0.6 (2.3) 
 
-3.3 (11.2) 
 
254 (85) 
9.4 (23.5) 
0.6 (0.8) 
232 
 
182 
 
4 
100 
29 
 
 
 
 

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Number of participants, 1:1 
randomisation 
Number of participants 
with 75% at post-tests 
464 
364 
8 
200 
58 
580 
455 
10 
250 
73 
 
The calculations are based upon a randomisation of 1:1, 50% of the participants participate in the 
standard program. Based on the power calculation, the total number of participants is estimated to be 
approx. 600 children. This is under the consideration of a completion rate of 75%. 
All outcomes will be analyzed by means of linear mixed models including two-way interaction between 
intervention (standard and intervention) and time (before and after) as fixed effect and child and site 
as random effects (to account for differences between children and between sites, respectively). 
Adjustment for age, sex, and possibly other covariates/confounders will also be included as fixed 
effects in the models. 
 
 

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Method 
Design 
Approximately 600 boys and girls in the age 7-14 years are recruited from two DCSH. The design is a 
cross-over design at DCSH level over a two-year period with two intervention groups: A standard group 
(with the standard program (SG)) and a standard + HIHE (SG+). In SG+ the children will, in addition to 
the standard program, play recreational football 2x45 min. a week. In SG the children will perform the 
planned activities according to the schedule. The training in SG+ will be performed indoor or outdoor 
on grass (depending on the facilities on the specific DCSH) with different football exercises (dribbling, 
ball control, passes etc.) and small-sided games with high intensity (3v3 to 5v5) on two goals. All 
training sessions take place on the DCSH or in the immediate vicinity of the DCSH. Every week, a 
specific football skill is connected with a health message. E.g., the skill of passing the ball to each other 
is related to respect of each other and avoid bullying.     
 
Training protocol 
Recreational football 
In keeping with studies on as well untrained men as on children (Krustrup et al. 2010a, Andersen et al. 
2010; Bendiksen et al. 2012, Ørntoft et al. 2016), the training consists of different football exercises 
such as passes, shots, dribbling etc., and as small-sided games. The small-sided games are performed 
as ex. 3v3 on small goals (2x5 m goals). 
The risk of injury is markedly higher in football matches (5 times higher) than during football training 
for young players (Brito et al. 2012). Nevertheless, it is emphasized, that muscle strains and twist 
injuries in joints also can occur during training on small goals. But the injury frequency for 10 year-old 
children in football training is approx. 5 per 1000 training sessions, and therefor low (Malina et al. 
2006). Furthermore, the FIFA 11 for Health pilot study, including Danish 10-11 year-old school children, 
did not report any injuries during the training (Ørntoft et al. 2016). 
 
Tests and measurements 
The participants will be tested in the start and end of their 10-week residential stay at the DCSH. 

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Furthermore, there are follow-up tests 3 and 12 months after their stay. The, in total, four tests days 
include measurements of physical fitness, physical performance, cognitive functions and 
questionnaires about health-knowledge, well-being and sleep patterns. For further descriptions, see 
below. Each test day is of approx. 4-5 hours duration.   
 
Measurements 
Each test day is planned in collaboration with DCSH staff or parents (the fourth test day) and are 
performed by a member of the scientific group (Human physiologists).  
 
Anthropometric measurements: Body weight and standing and sitting height are measured with a 
portable weight (Inbody 720) and altimeter, respectively. Moreover, the Inbody 720 will make an 
estimate of muscle mass and fat percentage. After a minimum of 10 min. of rest in the supine position 
in a quiet room, measurements of resting heart rate and blood pressure are performed.   
 
Balance and muscle strengths/horizontal jumping length: Balance performance is measured by the 
Stork test (Panta et al. 2015). It is measured on both legs, and best out of three trials counts as the 
result. The children stand barefooted or in one´s stocking feet on the floor. With eyes open and their 
weight on the entire sole of the supporting foot, arms on the hips, and the not weight-bearing foot are 
placed on the inside of the opposite knee. When the child has found his/her balance, the heel of the 
supporting foot is lifted, and the timer starts. Time stops for following reasons:  
 
• Hands/arms leave the hips. 
• The supporting foot moves. 
• The heel touches the floor. 
• The foot, which rests on the knee, is removed from the knee. 
 
 
Explosive leg strength is measured by standing longitudinal jumping, performed at two-legged offset 
and landing with arms placed on the hip in the starting position. The start position is behind a line on 
the floor and landing on a thin mat where the participants are instructed to land on their legs. 
Distances from the two-legged offset to the point where the rear heel affects the mat, is noted - best 

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out of 2 trials (Ortega et al. 2008, Reiman & Manske 2009). Standing longitudinal jump is correlated 
with both upper and lower body strength tests for children and adolescents and can therefore be 
considered as a general index for muscular fitness (Castro-Pinero et al., 2010). 
 
Aerobic fitness and intermittent performance: The original Andersen interval run test is used for 
indirect estimation of maximal oxygen uptake (Andersen et al., 2008). The participants run back and 
forth between cones on a 20m lane and touch the line between the cones at each end. After 15 sec. 
the participants stops as soon as possible (about two steps) and rests for 15 seconds. This procedure is 
followed for a total of 10 minutes. The 15 sec. periods are indicated by music that stops during rest 
periods. All participants start and stop the test at the same time. The distance traveled is recorded as 
test result. This test has previously been performed in 6-13 year olds, and no risks or adverse effects 
have been observed relating to the testing performed. The test is also validated for children in the age 
group 6-13 years (Andersen et al., 2008, Ahler et al., 2012). 
 
Cognitive functions: During the four test rounds, the participants are tested in a computer-based 
objective cognitive test battery that has been validated and verified in the age group 10-18 years to 
address children's cognitive functions (Cromer et al., 2015). The battery consists of four tests, which 
tests reaction time, attention, visual learning and long-term memory, work memory and executive 
functions (Cromer et al., 2015) - see further description below. 
 
The reaction time is addressed by a 'Detection Test' (Houx and Jolles, 1993). The participant sits with 
the dominant hand's index finger resting on a yes button on the keyboard. On the screen there is a set 
of playing cards in a pile facing upside down. When the test starts, the first card turns so that the 
image page appears. As soon as this happens, the participant must press the yes button. Then the card 
disappears into the deck and a new card is turned, to which the participant must press the yes button 
again. The participant will be encouraged to work as fast and as accurately as possible. Response time 
for correct answers in milliseconds (lower response time = better performance) is the primary 
outcome that is stored and used in the following analysis. 
 
The participants attention is measured using an ‘Identification Test'. The participant has the right and 
left index fingers respectively resting on one yes and one no button. On the screen there is a set of 

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playing cards in a pile facing upside down. The test is initiated and a playing card is turned and is either 
red or black. The participant must now answer whether the card is red or not by pressing either yes or 
no button in accordance with the required response. Then the card disappears into the deck and a new 
card is turned. Response time for correct answers and number of errors are the primary outcome. 
 
Participants 'visual learning are evaluated through a 'One Card Learning Test'.  At 'One Card Learning 
Test ', the participant is sitting with the right and left index fingers respectively resting on one yes and 
one no button. On the screen there is a set of playing cards in a pile facing upside down. The test is 
initiated by turning the first card face up. The participant must now indicate whether the card has 
been shown before in the test by either pressing the yes or no button. Then the card disappears into 
the deck and a new card is turned. The participant must try to remember all cards shown in the test. 
The proportion of correct answers and response time are the primary outcome.  
 
The participants 'working memory is addressed through a 'One Back Test'. The participant has the right 
and left index fingers respectively resting on one yes and one no button. On the screen there is a set of 
playing cards in a pile facing upside down. The test is initiated by turning the first card face up. The 
participant must decide whether the card is identical to the previously displayed card by pressing 
either the yes or no button. Then the card disappears into the deck and a new card is turned. Response 
time for correct response and the number of errors are the primary outcome. 
 
The testing is done individually in a room by a laptop or desktop computer with internet access. Data 
collection takes place by participants having a unique username and login, which is entered using a 
sent link from the investigators. The tests last a maximum of 45 minutes in total. 
 
Metabolic markers: Saliva Tissues collected by a Salivette tube are used to indicate the level of 
hormone insulin. The insulin level may indicate an increased risk of insulin resistance and type 2 
diabetes (Goodson et al., 2014). Spit samples are kept as cold as possible until they can be centrifuged. 
Samples are centrifuged, supernatant stripped into cryo tubes, stored at -20 degrees, later -80 degrees.  
Hair samples for the determination of long-term exposure to the biomarker Cortisol, consisting of 
approx. 100 hairs cut as close to the scalp as possible. It is kept in an envelope until analysis (Suavé et 
al., 2007). 

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Health-knowledge and general- and sport-psychological measurements 
By means of questionnaires we will, at baseline, at the end of the stay at DCSH and also 3 and 12 
months after end of stay, examine the participants' health, well-being / mental health, ego and task 
orientation, cohesion of participants, stress levels and sleep habits. During the completion of the 
questionnaires, there will be a test-responsible present to assist in the possible challenges of reading 
and understanding the questionnaires. Participants’ health-knowledge is measured through a 
questionnaire (Appendix 2) that examines the participants' learning and understanding of the 11 
health messages (Fuller et al. 2010, 2011, 2015, 2016). There is a total of 38 questions. The purpose of 
the questionnaire is to investigate how much participants have learned in each of the 11 health 
messages in the program. 
Participants' well-being / mental health are measured via PedsQL questionnaire (Varni et 
al., 1999, Appendix 3), as well as using a Kids Screen questionnaire (Ravens-Sieberer et al., 2001, 
Appendix 4). The questionnaires aim to measure the well-being of the participants. The scale intends 
to cover a wide range of dimensions in well-being and contains a total of, respectively, 22 and 25 
questions. A previous survey has tested the validity of the questions (Nunnally 1978). 
Participants' Ego- and task-orientation is measured through the Task and Ego Orientation 
Questionnaire (TEOSQ; Duda & Nicholls, 1992). The questionnaire contains 13 questions (7 for 
assignment and 6 for ego orientation), which can be answered on a Likert scale from 1 to 5, where 1 is 
"Highly Disagreeable" and 5 is "Fully Agree" (Appendix 5). Task-oriented participants emphasize doing 
their best, experiencing progress and / or improving skills while ego-oriented participants are 
measuring themselves against the others and emphasizing to be successful and better than others. The 
questionnaire is validated and translated into Danish. TEOSQ has been used in studies in Danish studies 
(Thomas et al., 2016). 
Participants' cohesion is measured via the Youth Sport Environment Questionnaire (YSEQ, 
Eys et al., 2009, Appendix 6). The questionnaire contains 12 questions that can be answered on a Likert 
scale from 1 to 5, where 1 is "Does not fit" and 5 is "Fits completely". Cohesion describes how the 
participant perceives the class's solidarity to social aspects and the ability to solve tasks in unity (Carron 
et al., 2002). The questionnaire is validated in English (Eys et al. 2009) and the Danish version has been 
used in similar studies (Elbe et al., 2016). 

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The Children’s Sleep Habits Questionnaire (CSHQ) is used in the assessment of the 
participants' sleep habits. The questionnaire is available in several versions (Appendix 7-8), containing 
33 or 26 questions for completing by the parents and the child itself, respectively. The questions are 
answered "Commonly" (5-7 t. Weekly), "Sometimes" (2-4 t. Weekly) or "Rare" (0-1 t. Weekly). The 
questionnaires clarify sleep habits, sleep disorders and consequences of disturbed sleep (Owens et al., 
2000a). The questionnaires are validated in English (Owens et al., 2000b), and CSHQ - parent version 
has been used in studies in Danish (Hjort et al., 2014). The children’s version will be used at baseline, 
after the 10week residential stay, as well as both 10 weeks and 12 months after the stay at DCSH, 
while the parent version will be used at baseline and 10 weeks and 12 months after the stay. The 
children’s version (Appendix 8) is attached in English. Before the start of the project, the version will 
review a translation process into Danish, back-translation into English, as well as pre-testing with 5-10 
children, and can thus be used as a self-reporting version. 
Participants' stress levels are measured via the Strengths and Difficulties Questionnaire 
(SDQ). The self-completion version for the children is validated in English (Goodman et al. 1998). The 
questionnaire contains 30 questions answered with "fails", "fits partially" or "fits well" within the last 6 
months (baseline - afterwards it is within the last month). The student version (Appendix 9a + b) will be 
used at baseline after the stay, as well as both 10 weeks and 12 months after the stay at DCSH (Obel et 
al., 2004). The questionnaire reveals symptoms in emotional, behavioral, hyperactivity / concentration 
and social challenges. The questionnaire for parent completion (Appendix 10a + b) was previously used 
in studies with Danish youth (5-12 years) (Kristensen et al., 2014, Niclasen et al., 2012). The parent 
version will be used at baseline and 10 weeks and 12 months after the stay. 
 
Other measurements 
In addition to the above test days, the following measurements are performed during the high 
intensity training in the SG+: 
 
Continuous intensity measurements during training 
 
Frequently during the training intervention, activity registrations will be made. There will be measured 
up to 4 times at approx. 50 participants from both DCSH. Activity registrations include pulse rate 
measurements (Polar Team 2), GPS measurements and accelerometer measurements to determine 

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intensity and motion pattern analysis. At the trainings where activity registrations are made, short 
questionnaires are also provided for measurements of perceived exertion and flow in relation to the 
training (Elbe et al., 2010, Appendix 11). In relation to accelerometer measurements, there will also be 
a record of participants' daily activity level and sleep patterns, up to 25% of participants, during the 
intervention period. 
The questionnaires, within the various measurement areas, are based on already tested reliability 
questionnaires relative to the participant population, cf. the above references. The questionnaires are 
introduced by a qualified person with relevant professional education, which is also present during the 
completion of the forms. The answers to the questionnaires are treated confidentially as all other 
individual results. The participant will not be asked to give up his name and the questionnaires will be 
coded. 
 
Additional information 
Via a parent-filled questionnaire (Appendix 12) knowledge about socioeconomic data, ethnicity, 
background information and health surveys are obtained. Absence lists, as well as results from school-
related tests, are also obtained through the DCSH in order to utilize the large number of participants in 
various subgroup analyses. 
 
Side effects, risks and disadvantages of the participants 
Tests and measurements 
Overall, tests and measurements in the study are non-invasive. In relation to the training intervention, 
football represents an activity that children already do to a large extent in daily life: Children play 
soccer, running and jumping, etc. Therefore, there are no particular risks considered for these activities. 
There may, however, be injuries in football training, but the injury rates are low, see section on 
training protocol. 
 
Biobank 
Hair samples and salivary samples are anonymized and stored for total analysis after completion of the 
test period. All samples are destroyed after analysis. Hair samples are stored at room temperature, 
and saliva samples on freezer (initially -20 degrees, then -80 degrees). 

Protocol – Danish Christmas Seal Houses, HIHE 
 
 
 
18 
 
Scientific ethical statement: Advantages and risks 
Football training for 10 weeks is considered to be a training improvement and generally health-
enhancing for recruited participants. More generally, it is a declared goal of the study to contribute 
with information that can form the basis for recommendations regarding health effects of football 
training for overweight children at DCSH. In relation to paediatric research, the project will be able to 
contribute with new knowledge about the effects of a health-enhancing model and this society benefit 
is estimated to exceed the risks for the children in both the training and the various tests. 
All training and tests are carried out by staff with the right professional qualifications. The 
well-being and safety of the participants will be of highest priority. There will therefore be great 
attention to the well-being of any specific child in carrying out the protocol's procedures, and the child 
will be excluded from the study if it is considered to be the best for the child, and subsequently the 
child and his/her parents will be informed of the basis for the decision. As a participant / parent, 
knowledge of the state of health in the form of blood pressure and the child's physical ability is given in 
addition to knowledge of intermittent exercise capacity, balance and spring strength. Compared to all 
these measurements, participants / parents will be able to see how he or she is relative to the average, 
so that it can be evaluated whether the child is over, below or in line with the standard. Only 
participants / parents receive the results of the individual measurements. As for the participants in the 
DCSH with the standard program, they must follow the standard program, and are, through 
participation, given test results and other information of personal interest. 
 
Personal information 
The study is reported to the Data Inspectorate as a public research project under the Institute's Joint 
Review System, by journal number 2015-57-0008. Information regarding the participants is protected 
under the Personal Data Processing Act - Personal Data Act and Health Act. All data will be encoded so 
that participants' results can only be identified by relevant persons. After the intervention period, each 
participant will have the opportunity to access own data and average data for the entire group. In the 
consent statement, parents respond to whether the participants/parents want access to their own 
data within four months after the end of the project. Information that appears in connection with the 
research project is subject to confidentiality. By publication in a scientific journal, all data will appear in 
anonymous form. Both positive, negative and inconclusive results will be published. 

Protocol – Danish Christmas Seal Houses, HIHE 
 
 
 
19 
 
Authorities, controlling health science research projects have the right to access data; 
these authorities will also be subject to professional secrecy. All data will be fully anonymized after the 
end of the project. 
The study is conducted in full compliance with the Helsinki Declaration. 
 
Financial aspects 
The project is initiated by Peter Krustrup, Professor of Sport and Health, at the Department of Sport 
and Biomechanics at the University of Southern Denmark and Honorary Visiting Professor at the 
University of Exeter, England. The project is funded in collaboration between the University of 
Southern Denmark and the University of Copenhagen. There are rcieved funds from TrygFonden,  
Helsefonden and Augustinusfonden for manpower and measuring equipment. All external co-financing 
will be deposited on a SDU research account subject to public audit. If further support is granted to the 
project in connection with other applications, the Regional Scientific Ethics Committee will be 
informed of this and the participant information will be updated with the name of the grantor and the 
amount of support. The updated participant information will be provided to the participants. There is 
no one in the project group that is affiliated with private companies or funds with interests in the 
research project. 
 
Remuneration or other benefits 
Compensation for transport costs or loss of earnings for the parents is not compensated because all 
testing and training takes place at the DCSH or in the participants own home. 
 
Recruitment of participants 
The participants are recruited from two DCSH. In the project's cooperation agreement, it is specified 
that two of the DCSH change practice for one year. In this manner, all the children at the two DCSH are 
participating in the HIHE intervention, regardless of their participation in tests. To investigate the 
standard program, all tests will be carried out at both of the DCSH for one year. After the first year the 
two participating DCSH change intervention group. Alongside the general information about the stay at 
the DCSH, written information about the study will be provided and subsequently an oral information 
meeting / parent meeting cf. the description below. 
 

Protocol – Danish Christmas Seal Houses, HIHE 
 
 
 
20 
 
Publication of study results 
The intention is to publish scientific articles on the results of the project during 2021-2022, including 
both the short and long-term effect of the DCSH standard program and the effect of the HIHE program. 
If it is not possible to publish the results in a journal, the results will be published otherwise. The 
primary test results will also be published in Danish in 2021, partly as a research report in Danish and 
partly in short format for use in DCSH setting, both in printed and electronic versions. In addition, the 
plan is to organize at least two seminars on the DCSH efforts and the local follow-up to the DCSH 
efforts by 2021. Both positive, negative and inconclusive results will be published. The project is 
registered at www.clinicaltrials.gov 
 
Insurance 
The trial participants will be covered by the "Law on Complaints and Compensation Access in the 
Health 
Care" 
Act 
(see 
Act 
No. 
1113 
07/11/2011 
www.retsinformation.dk/Forms/R0710.aspx?id=138893). 
 
Providing oral information and obtaining consent 
The potential participants are not yet of legal age, and therefore cannot give their consent for 
participation in the study without parental consent. Parents of the potential participants will receive 
written information about the project at a meeting at the DCSH eight weeks before start-up 
(participant information and the booklet entitled "Experimental Rights in a Health Science Research 
Project" published by the Scientific Ethics Committee Aug. 2014). Thereafter, an information meeting 
(8-24 families) will be held at the specific DCSH, with potential participants and their parents, where 
qualified project staff who have been assigned this task delegated by the project manager provide oral 
information on the background of the study, purpose, study protocol, methods used and any risks and 
side effects as well as review the leaflet "Before You Decide" published by DNVK Aug. 2014. These 
meetings are held every 2 to 3. week at each DCSH. The child will also receive the oral information at a 
level that fits its age and understanding frame by a project employee with experience in 
communicating to children, and the child is involved in the conversations with the parents about the 
study to the extent that the child can understand. The child's opinions will, to the extent that they are 
relevant, be given importance. It is emphasized that the content of the oral information is 
disseminated to suit the target group, 7-14-year-old children. 

Protocol – Danish Christmas Seal Houses, HIHE 
 
 
 
21 
 
The parents are informed in advance of the oral information meeting that they may bring an observer 
to this meeting. After submitting the oral information, we offer 1 day's reflection time in relation to 
the final commitment and signature of the consent statement, but it will also be possible to give 
consent immediately after the oral information is provided. Deputy consent will be obtained from both 
custody holders; however, one custodian may give the other proxy to sign on behalf of both. By proxy, 
it should be clearly stated what the purpose is (participation in the HIHE program at DCSH) and for the 
duration of the proxy (12 months after the end of the stay at the DCSH). It is emphasized that they can 
at any time withdraw from the study. The submission of consent to participation in the project is 
adapted to the other information and consent of the DCSH. 
Throughout the process, we will endeavour to have a high level of information to ensure that all 
parties feel well informed and safe in attending and completing the study. Thus, an electronic video 
version of the oral information will also be prepared for parents who will see it again at home. 
Emphasis will be placed on the fact that the children understand that they voluntarily participate, and 
their parents are giving their consent to their participation, that they can stop their participation at all 
times without giving reasons and that this will have no consequence for them. We are aware that 
there may be pressure on a participant, for example, if he/she is the only one at the DCSH that does 
not want to participate in the study. From the project team, we will do what is possible to ensure that 
no one feels pressured to participate. This aspect will also be addressed in the oral information. 
No project-related procedures are performed until there is proper consent signed by the parent / 
authority owner, project manager or project officer who has been delegated the task by the project 
manager. The test participant / parents are offered a copy of the consent statement. 
 
 

Protocol – Danish Christmas Seal Houses, HIHE 
 
 
 
22 
 
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