Current physical activity and sports history of children 11 to 19 years old at high schools in Prague

Objectives. Objective of this study/thesis/work was to analyse the level of free time physical activity and its specifics on a sample of the adolescent population. To goal was to analyze the historical factor in each proband and its effect on the activity development. The analysis included information spanning from the initial experience with organized physical activity. The results of the survey are further compared with the conclusions of previous studies on the issue. Methods. A total of 563 respondents (235 boys and 328 girls) from grammar schools in Prague participated in the research. Data were obtained using a questionnaire survey (computer assisted web interviewing – CAWI) based on preliminary research and evaluated using MS Excel, GraphPad Prism and mathematical software R. Results. The preference of just one sport (63.8%) was found in the examined population. Predominant frequency of trainings was 2 to 4 per week (61.2%). The vast majority (93.6%) stated that they participated in fundamental movement training at a younger school age. More than half (61%) experienced pain or injury during physical activity, especially in the lower limbs (61.9%). The main factor in the termination of physical activity were psychosocial reasons (76.9%). Increasing age has not been shown as a factor leading to reduction of physical activity in children. On the contrary, the frequency of activity increased as the children aged (p = 0.02). There was no significant dependence of the current activity on the completion of fundamental movement training (p = 0.08), nor was the confirmation of a general trend of higher activity of boys compared to girls (p = 0.64).


INTRODUCTION
With the rapid development of information technology, there is an ongoing discussion of its effects on decreasing physical activity in children. The relevance of the issue is confirmed mainly by the global trend of declining physical activity and quality of movement, which is influenced by several factors. The main initiating reasons for conducting the study of children's activity are the impact on health and quality of life. The main areas of interest are importance of physical activity, beginning of physical activity, its frequency and subsequent development, including influencing factors during adolescence.

THEORETICAL BACKGROUND
Research clearly shows that adequate fitness and physical activity results in significant health benefits for individuals as well as significant socio-economic benefits for society as a whole. Examples of health benefits may be reduced risk or at least delayed onset of civilization diseases, such as childhood obesity or a proven positive effect of activity (and physical activity automatically leads to psychological) on delaying and possibly alleviating the onset of dementia at senior age (Care, 2019;Findholt, 2007;Guthold, Cowan, Autenrieth, Kann, & Riley, 2010;Khan et al., 2009;Rolland, van Kan, & Vellas, 2008;Verghese et al., 2003).
According to the study (Telama et al., 2005), it was concluded that a high level of physical activity at the age of 9 to 18 years, especially in the case of its continuity, significantly correlates with a high level of activity in adulthood. Simultaneously, another study (Dumith, Gigante, Domingues, & Kohl III, 2011), summarizing facts from a adequate 26 studies, evaluated physical activity using a questionnaire and found a decrease during adolescence by an average of 7.0% per year.
The worldwide trend of insufficient activity of adolescents (11 to 17 years) implies the need to address this situation. A study (Guthold, Stevens, Riley, & Bull, 2020) conducted by WHO researchers showed that more than 80% of adolescents worldwide did not follow the recommendation of at least one hour of physical activity per day (Gába, 2018;Martins, Marques, Sarmento, & Carreiro da Costa, 2015). Several studies from different years (Downward & Rasciute, 2015;Draper, Basset, De Villiers, & Lambert, 2014;Sherar, Esliger, Baxter-Jones, & Tremblay, 2007;Trost et al., 2002) (Care, 2019) point to the fact that boys are more physically active than girls in all ages at all ages. Guthold et al report prevalence of insufficient physical activity in boys 78% and in girls 85%. In connection with gender, on the basis of this study, numbering 1.6 million probands, students from all 146 countries, girls can be identified as less active compared to boys (Guthold et al., 2020).
Ending a sports career is a highly discussed topic, especially in relation to the elite sphere. The literature (Alfermann, Stambulova, & Zemaityte, 2004;Jansa, 2017) in relation to the end of a (professional) sports career introduces a basic division into involuntary (forced by circumstances) and voluntary termination (free choice).
Among the psychological factors, there are specifically reasons such as: lack of or, conversely, excessive motivation, dissatisfaction or frustration due to failure to achieve set goals, anxiety caused by excessive pressure. Examples of social factors include: loss of a sports partner, unsatisfactory environment or team, disagreements and bad relationships within the club or with teammates, other hobby activities, work or study workload, lack of time for the family, loss of family support (Crespo & Miley, 2003;Moesch et al., 2012).

OBJECTIVES OF THE WORK
The aim of the work was to obtain and analyze data on the subject of the current state of physical activity of children from multi-year grammar schools in Prague, including the sports history of each proband. The work is focused on the history of the beginning of the child's involvement in the sport and its further development up to the present. The partial goal is to investigate the reasons for the termination of physical activities, as well as the reason for avoiding physical activities in a given sample of the population.

METHODS
The work is an empirical quantitative study. A one-off anonymous questionnaire survey was used to obtain data via an electronic form at selected multi-year grammar schools without specialized focus of study in Prague. The researched phenomenon is physical and particularly sports activity at the time of research, including the history of its development in specific individuals.
The research group consisted of children regardless of gender between the ages of 11 and 19 attending selected multi-year grammar schools in Prague, which, through management, agreed to the children's participation in the study. The reason for selecting this subpopulation is the homogeneity of the sample in terms of age and social classification and at the same time the personality spectrum of children. The number of individuals in the sample was limited by the number of these facilities in Prague and the willingness of school management to participate in the research. Subsequently, a responsible, non-participating person was contacted, who ensured the distribution of the form among students of specific classes.

Data collection method
The questionnaire was created in the form of CAWI (Computer-Assisted Web Interviewing), ie online research including distribution and data collection. The environment for the form or the questionnaire was provided by the Google Docs service. The final form of the questionnaire contained a combination of question forms. The most frequent was the form of closed questions of alternative (selective) and enumerated type. Within several open questions, one can also be considered as control for previous answers.
Data collection took place in the period before and after the summer holidays of 2019. Most schools, or school management, used information technology lessons to complete the questionnaire. Other schools sent a link to the questionnaire directly to the students using school e-mail addresses, and educators orally introduced them to the essence of the research. After the collection, the data were converted to a table in csv format for further analysis.

Factors of termination of physical activity (PA)
For the purposes of this work, the division of reasons into main groups (factors) was created on the basis of answers. Psychosocial factors (Cumps, Verhagen, & Meeusen) included responses such as a psychological block based on an event within the collective or the collective as such, moving, but also loss of interest and motivation. Health factors (H) included all the answers on the topic of long-term illness, injury or injury limiting the comfortable continuation of PA. Training factors (T) included the options of the coach leaving, high demands on the respondent, the breakdown of the club, category or association, as well as capacity issues.

Data processing
The total number of completed questionnaires (n = 566) was checked and any incorrectly completed questionnaires were removed and excluded from further analysis. The control of the data thus consisted in the assessment of the factual content, the authenticity of the answers and the elimination of meaninglessly filled in forms (especially open-ended questions).

Data analysis
As part of quantitative research, the analysis of descriptive statistics was carried out in two phases. The classification of the first stage took place mainly using the MS Excel environment, including output tables and graphs, or the calculation of mean values. The GraphPad Prism 8 system and the R mathematical system were used for the statistical analysis of the second stage, including graphical representation.
For all second-stage analyses, descriptive statistics and normality tests (Shapir-Wilk, Kolmogorov-Smirnov, and QQ plots) were first calculated for the data to test whether the values were from the normal probability distribution. Based on the result, a choice was subsequently made between tests for parametric or non-parametric data distribution for hypothesis testing.

Correlation analysis
For all examined dependencies, Spearman's test was used for correlation analysis due to non-parametric distribution of data (normality tests had a negative result). Th e signifi cance level was maintained at its standard value of α = 0.05 (5%) and had a two-sided p-value variant for all analyses.

Comparison of two selections
To test one of the established hypotheses, a comparison of two sets was used, namely boys and girls and their volume of physical activity per week. Due to the repeated negative result of the normality tests, the Wilcoxon two-sample test (Mann-Whitney) was used. For this analysis, the level was also set at α = 0.05 (5%) with a variant of the two-sided p-value.

File characteristics
Aft er excluding incomplete questionnaires, the girls represented a majority (n = 328; 58%) compared to boys (n = 235; 42%). From the graphic visualization, this ratio is visible in all age groups except at 13 years, where there is a higher proportion of boys. Th e age distribution of respondents shows a higher proportion of high school children at age 15 years (n = 134; 23.8%) and 16 years (n = 120; 21.3%). On the contrary, the extreme groups reached a markedly low proportion, 11 years (n = 12; 2.1%) and 19 years (n = 10; 1.7%).

Types of sports
Th e total sum of answers signifi cantly exceeds the number of respondents due to the possibility to choose more physical activities. Th e possible choice of sports was dominated by swimming (n = 261; 50.2%) and martial arts (n = 131; 25.2%). Among Lukáš Babický, Tereza Nováková, Jan Vávra, Lenka Satrapová girls, dance was also frequent (n = 71; 23.9%). Less common sports include tennis (59; 11.3%), athletics (58; 11.2%), girls' volleyball (n = 43; 14.5%) and boys' fl oorball (n = 43). 37; 16.6%). A slight surprise is the result of football (n = 38; 7.3%), which is numerically only slightly above the mean value (Me = 29). Despite the eff ort to include all of the most probable types of sports activities, it was obviously not possible and the group "Other" was the most frequently selected (n = 332; 63.8%).

Frequency and volume of physical activities
Th e visible conditional formatting of the table data, including additional fattening, shows that more than half of the interviewed children play sports with a frequency of two to four trainings sessions per week (n = 318; 61.2%). About a third of children complete more than 5 trainings (n = 137; 26.3%). In case of the total amount of time devoted to sports, including competitions, 3 to 6 hours per week represent almost a half of the average values (n = 229; 44%). However, a significant number of children answered that they spend 7 to 8 hours a week playing sports (n = 76; 14.6%) and the same amount even up to 12 hours (n = 76; 14.6%).

Muculoskeletal disorder as a limitation of sport
All respondents were asked about the musculoskeletal disorders associated with sports, possibly in recreational form. The answers were evenly distributed, only the answer "No", ie no experience with difficulties in sports was slightly more frequent (n = 219; 38.9%). Girls (n = 104; 31.7%) reported slightly more frequent difficulties (pain) than boys (n = 62; 26.4%). In the majority of cases it was a sport restriction of a temporary nature (n = 210; 61.0%). Other options were relatively rare. Only in 15.7% (n = 54) of cases there were no restrictions in sport. Restricted mobility occurred in boys in 20.0% (n = 28). In contrast, in the case of girls, there was a relatively high percentage (n = 78; 38.2%) of recurrent pain.

Factors of reduced physical activity
For the purposes of the investigation, the question on the subject was of an open type. Based on the answers and theoretical background, a categorization of factors (reasons) for the termination of PA was created. The summary of the survey results is presented in Table 16. Graph 8 shows the predominance of factors that were defined as psychosocial (n = 70; 76.9%).

Relationship between age and volume of physical activity
In an effort to determine the connection between different ages and total weekly activity, a correlation analysis was performed. For a set of 520 participants aged 11 to 19 years, the median value was calculated to Me = 5.5. In the retroactive conversion from nominal value, the median corresponds to the option "5 to 6 hours". The graph below shows the linear regression curve. Although it has an increasing tendency (r = 0.01), the p value (p = 0.80) is insignificant with respect to the determined level of α (0.05). And the assumption that the volume of physical activity will decrease in older age has not been confirmed, it even has the opposite tendency.

Graph 2 Representation of categorized reasons for termination of PA in adolescents (medical reason = health category)
Graph 3 Dependence of the volume of physical activity on the age of respondents, including the difference by gender; linear regression

Relationship between age and frequency of physical activity
Similarly, to study the correlation between age and frequency of PA, the analysis was performed first in the original age range. The investigated dependence of the frequency of physical activities on age has already been found to be statistically significant at the level α = 0.05 (p = 0.02), confirming the higher frequency of PA with increasing age.

Graph 4 Dependence of the frequency of physical activity on the age of respondents, including the difference by gender; linear regression
Graph 5 Dependence of the frequency of physical activity on the volume of activity Graph 6 Average volume of physical activity in girls and boys

Gender and volume of sports activity
Comparison of the two groups by non-parametric test shows the expected tendency of higher physical activity of boys compared to girls, but with insufficient value of significance (p = 0.64) at the determined level of α (0.05). On the box graph (reference to the graph) it is possible to see identical median values, but a different 75% percentile, which is equal to 7.5 ("7 to 8 hours") in girls, 9.5 ("9 to 10 hours") in boys.

DISCUSSION
In the group of students from multi-year grammar schools in Prague, the value of the correlation coefficient was positive, so with increasing age there is a tendency for the time spent on physical activity to increase. However, in relation to the question on the total number of hours of physical activity per week, insufficient value was reached for statistical significance.
With the same tendency but with sufficient p-value (significance) in this research, it turned out that a specific population of children plays sports more often as they age. However, it cannot be said with certainty that they spend more time during the week on physical activities.
Globally, several longitudinal, cross-sectional, and other studies recognize that there is a significant decrease in activity during adolescence (Collings et al., 2015;Dumith et al., 2011;Martins et al., 2015;Murray, Calderwood, O'Connor, & Mutrie, 2016;Reilly, 2016). This fact was recorded as early as 1998, when Gavarry et al. confirmed this tendency in moderately intensive activity (Gavarry et al., 1997). The 2003 study reached the same result in the Moderate to Vigorous Physical Activities MVPA relationship (Mota, Santos, Guerra, Ribeiro, & Duarte, 2003). The linear course of decrease in PA (from 9 to 17 years of age) and the specific breakpoint (14 years) were described by Wall et al. with the subsequent largest decline in PA in both genders (Wall, Carlson, Stein, Lee, & Fulton, 2011).
However, in recent history, there have also been studies that have not found an evident decrease in the physical activity of adolescents (Harding, Page, Falconer, & Cooper, 2015;Mitchell et al., 2012). In their conclusions Harding et al. only confirmed the increased value of time spent in a sedentary manner. Another study confirmed a decrease in activity, but only of a mild nature, especially in the case of boys .
Research in the Czech Republic, Rubín points to the equally surprising result of the increase in physical activity with increasing age (Rubín et al., 2018). However, this is a research on the population of adolescents with the MVPA measurement. However, the author points out the generally declining trend of the common physical activity (for example, taken steps) in the population of Czech adolescents since 1998.
Despite the fact that Rubín studied MVPA on a common sample of the adolescent population, the study took place in the context of an artificially built environment (Rubín et al., 2018). These were larger cities, with the exception of Prague, but the trend in the results still coincides with our results.
The original assumption was that with the increasing complexity of teaching, the amount of time devoted to physical activities will decrease. It can be assumed that with older age the frequency of PA increases, for example due to more frequent match-es or racing activities (Way, 2019). The results of this work could also be explained by a general increase in the complexity of training plans in most sports based on the physiological development of the child's body. According to the LTPD recommendations, in the case of training a hockey player from the age of 12 to the age of 18, increases the time on ice during training and the number of matches increases by up to half (Wall et al., 2011). In the case of swimming, by the age of 12 years, the recommended time spent in the pool doubles (American Swimming, 2017;Radford, 2008). In the next period, up to about 18 years of age, however, the volume is maintained and there is more focus on specialization and periodization.
The disadvantage of the questionnaire survey with regard to the conclusion of not only this hypothesis could be the insufficient understanding of the term "performance sport" by students. It is not possible to trace back which of the respondents is a performance athlete and which is only a recreational one. Thus, there is no differentiation of the level of PA in individual respondents. The question is to what extent this difference affects the results. Just in the sense that we expect regular, intensive training for performance athletes. For recreational athletes, it may be a lower intensity and even an irregular PA.
Another result was the confirmation that the most common reason for the reduction or termination of dominant sports and physical activity is psychosocial factors. Respondents in the questionnaire survey listed the reasons for which they ended the sport. It was an open question.
The most common factor was psychosocial reasons in terms of lack of time and, in general, the time required for physical activity and its effect on school workload. The very next reason was the loss of interest, especially the lack of fun and the lack of a sense of fulfillment from the activity. Only half of the responses stated the reason for no longer participating in PA as an injury or illness. Ultimately, we can interpret these answers as the fulfillment of both parts of the term "psychosocial".
The categorization of factors itself is not entirely unambiguous, because according to the cited literature, the reasons for the termination of sports activities are very often multifactorial.
Several studies (Azzarito & Hill, 2013;Knowles, Niven, & Fawkner, 2011;Slater & Tiggemann, 2010) state that adolescents do not value competitive-type physical activities (exposing them to competition) and, paradoxically, for them, the performance-motivating climate is a barrier to further sports activities. Adverse factors included adolescent pressure for victory, failure in front of peers, and negative peer reactions; feeling discomfort or lack of fun. One factor was also the lack of study opportunities Quaresma, Palmeira, Martins, Minderico, & Sardinha, 2015). Even in our investigation, there were reasons such as high demands of coaches or the team. A very common reason given by girls in particular (60%) in the research of Kimm et al. is the lack of time for PA (Kimm et al., 2006). Another reason was fatigue and lack of interest in activity.
Although some studies Quaresma et al. mention the considerable importance of the influence of the family, especially parents, none of the respondents answered in this sense (Quaresma et al., 2015). For children who have avoided PA all their lives, the role of parents could play a role in not leading the child to physical activities. The possibility of limited funding, i.e., socio-economic status (SES), concerned only one respondent. However, according to the results of the study , it was found that lower SES leads to a demonstrably lower incidence of MVPA during the day.
The higher sports activity at older school age of boys compared to girls is pointed out by many authors of various studies. It is possible to consider the same tendency in the case of this research, but in this case the value ensuring the significance of the result was not achieved. Globally, there is a decline in activity during adolescence, which is more pronounced in girls than in boys (Barnett, Ridgers, & Salmon, 2015;Bringolf-Isler et al., 2015;Brodersen, Steptoe, Boniface, & Wardle, 2007;Collings et al., 2015;Metcalf, Hosking, Jeffery, Henley, & Wilkin, 2015;Reilly, 2016). Martins et al. speak of higher evidence in the case of older adolescents boys .
However, four other studies Harding et al., 2015;Mitchell et al., 2012) do not support the general view that the decrease in PA during adolescence is more pronounced in girls than in boys. Even in an older study by Gavarry et al. did not find a gender difference in different intensities of PA (Gavarry et al., 1997). In contrast, Collings et al. found a slightly higher decrease in boys than in girls (Collings et al., 2015).
The study of Rubín (Rubín et al., 2018) did not confirm significantly higher or otherwise different physical activity in Czech adolescent boys compared to girls. On the contrary, the results of a significant difference in PA in favor of boys were obtained by the Czech authors (Frömel, Novosad, & Svozil, 1999). The girls lagged behind in both intensity and volume of activity (Neuls & Frömel, 2016).
Very interesting results are summarized in the publication of Rychetský and Tilinger, where they compare participation in PA by gender using COMPASS methodologies from 1998 to 2015. In general, the difference in activity by gender was confirmed in terms of higher decline in girls, especially in the form of unorganized sport and PA. The authors summarize the facts into a general statement that boys are more involved in intense, organized activities than girls, who prefer unorganized PAs of lower intensity and frequency (Rychtecký & Tilinger, 2018).
Inconsistent results point to the complexity of defining a clear conclusion. The results are probably strongly influenced by a specific population sample. The issue of comparing studies is not only the possible implementation of different ethnicities, performance groups, but of course also different approaches to data acquisition. In general, questionnaires are often used in this field. However, these are slightly criticized for possible data bias. Pedometers seem to be more reliable, but they only provide data on the number of steps. Accelerometers appear to be the most suitable form. Larger studies use a combination of at least two measurement methods.
A slight indication of the difference between the activity of boys and girls also appeared in this study. This would be in line with the conclusions of the above-mentioned research by Rychetský and Tilinger, i.e. that boys prefer more intensive and organized forms of activities. This should theoretically explain slightly higher numbers in boys, both in terms of frequency and total PA volume (Rychtecký & Tilinger, 2018). However, the difference is not significant, as girls are not literally less active, but only select activities of lower intensity. We can also consider the higher responsibility of girls in their studies, or the effort for a better benefit compared to the common approach of the majority of boys.
While the level of fundamental motor skills (FMS) is demonstrably associated with the current level of PA and fitness of both younger school-age children and adolescents (Capio, Sit, Eguia, Abernethy, & Masters, 2015;Jaakkola & Washington, 2013;Lai et al., 2014;Morgan et al., 2013), the question is whether this is also the case in terms of future activity levels.
As a result, most studies on this issue repeatedly mention the importance of completing the "active start" phase providing early childhood (up to 6 years of age) training in FMS (skills). Barnett et al. even state motor competence in childhood as a predictor of activity in adolescence, however only evaluated by respondents independently (Barnett et al., 2015). The above-cited study indicates a significant relationship between physical training, i.e. obtaining a sufficient level of FMS and the activity of children and adolescents. However, it is assumed that activity levels and motor skills may be affected by other factors such as self-perception, socioeconomic status, and family attitude toward PA (Barnett et al., 2015;Freitas, Gabbard, Caçola, Montebelo, & Santos, 2013;McGrane, Belton, Powell, & Issartel, 2017).

LIMITATIONS
The representation of respondents of individual age categories is strongly influenced by the approach of school management to filling in the questionnaire form. It is obvious that, especially for marginal age groups, the form was distributed only via school e-mail.

CONCLUSION
Due to the global lack of exercise in addition to the prevalent sedentary lifestyle, there is a lot of research and studies mapping the issue. The positive result of this study is that the trend of decrease in the volume of physical activity with increasing age of the child was not confirmed. On the contrary, the results suggest that with increasing age, the frequency of physical activities in the studied population increases. This cannot be stated unequivocally in the case of girls in whom the increase in frequency does not reach the level of significance. For the total volume of activities, however, the results did not confirm a significantly higher activity in boys compared to girls. The significant dependence of physical activity on the completion of physical training was also not confirmed. Conformity with general findings, on the other hand, was found in the localization of the most frequent problems (pain, injury), which turned out to be predominantly in the lower limbs (esp. knee and ankle). However, psychosocial factors most often led adolescents to reduce or stop physical activity.
We see the importance of the results of the work mainly in the specification of the current situation of physical activity in the selection of the adolescent population. In a given sample of the population with increasing age, there is no significant reduction in the volume of physical activity. Support for activity therefore seems appropriate and beneficial for individuals who, for psychosocial reasons, leave the activity completely. In some cases, the solution could be offering the possibility to simply change the type of activity or level of performance to relieve pressure on individuals.