Exploring the effects of three different types of cognitively challenging physical activity games on students’ executive functions and situational interest in physical education

Abstract This study compared the effects of three different types of cognitively challenging physical activity games on students’ executive functions and situational interest. Participants were 140 students from four fourth-grade and four fifth-grade classes of four elementary schools. One fourth- and one fifth-grade class from each school were randomly assigned to the three experimental and the control group conditions. A group-randomized controlled trial design was used in this acute experiment including a single physical education session with pre- and post-test measures of executive functions and a post-test measure of situational interest. Students of each experimental group played physical activity games based on a different principle of mental engagement (i.e., contextual interference, mental control, or discovery). Control group students did not participate in physical education. The results showed positive effects of all types of cognitively challenging physical activity games on experimental group students’ executive functions compared to control group students. No differences were found on executive functions and situational interest between the three experimental groups. These results provide supporting evidence regarding the utilization of cognitively challenging physical activity games for involving students in physical activity and triggering their executive functions.


PUBLIC INTEREST STATEMENT
School physical education has the potential to affect positively students' four developmental channels, namely, physical, emotional, social, and cognitive. Regarding the physical channel, the health-enhancing benefits of physical activity and its positive effects on the development of various body systems are well documented. This is coupled with sufficient evidence on the positive effects of physical education on social and emotional development given proper delivery methods. Until recently, however, it was less clear which type of activities may enhance students' cognitive function. To this end, recent research has examined the impact of different physical activities on students' executive functions. These are higher-order cognitive processes involved in novel, challenging, and complex situations when concentration and attention is needed. In this line of research, this study showed that games designed to pose cognitive challenges to students had positive effects on their executive functions.
This view is based on evidence showing positive associations between physical activity and functional changes in the brain that are paralleled by enhancements in cognitive function (e.g., Donnelly et al., 2016;Khan & Hillman, 2014). Moreover, research has suggested that the cognitive demands of complex motor tasks offer optimal conditions for cognitive enhancement (Moreau et al., 2015). This new approach calls for increasing physical activity in combination with a shift "from simply moving to moving with thought" (Diamond, 2015, p. 1). That is, physical activity programs should be developed following the idea of "filling two needs with one deed" (Donnelly et al., 2016) focusing on both cognitive and motor development.
Special consideration in research regarding the association between physical activity and cognitive development has been given to executive functions (Pesce et al., 2018). Executive functions refer to a family of higher-order cognitive processes involved in goal-directed, flexible, and adaptive behavior. These processes are responsible for cognitive flexibility and adaptability of goaloriented behavior triggered in novel, challenging, and complex situations when concentration and attention are needed (Diamond, 2013). There is a general consensus regarding three core executive functions, namely, inhibition, working memory, and cognitive flexibility (Diamond, 2015).
Inhibition allows students to block thoughts, stimuli or actions that have become unsuitable due to changing situations, in order to control behavior, emotions, attention, and thoughts in order to take the most appropriate action (e.g., a student inhibits a call from peers to focus on proper execution of a task). Working memory refers to short-term storage and handling of a relatively limited amount of information that is needed to act effectively (e.g., a student holds information for correct execution of two motor skills to combine them effectively in a sequence). Cognitive flexibility allows students to be flexible in changing perspectives or approaches while solving a problem and to adjust to new demands, rules, or priorities (e.g., a student changes the process for solving a problem if the one he or she uses is not effective).
Executive functions are essential for mental and physical health, quality of life, and success in school and life (Diamond, 2013). They are also considered important for school readiness (Blair & Raver, 2015) and academic achievement in subjects such as language, math, and science (e.g., St Clair- Thompson & Gathercole, 2006;Mazzocco & Kover, 2007). Executive functions are utilized by students in order to organize, remember, and apply knowledge, to manage time, materials, and ideas (Meltzer, 2007) and thus to execute and monitor sequences of actions necessary to successfully perform academic tasks, such as solving a new complex mathematical problem or comprehending a complex phrase (Cantin et al., 2016). In sport, executive functions were a mediator in the relation between motor ability and academic achievement (Schmidt et al., 2017). Moreover, the development of executive functions is considered as a means of enabling self-regulation and efficient metacognitive control (Roebers, 2017) which in turn have been associated with positive outcomes in various educational settings including physical education  such as improved motor and sport performance, satisfaction, enjoyment (Kolovelonis et al., 2010, and self-efficacy (Kitsantas & Zimmerman, 1998).
There has been growing evidence that children's executive functions can benefit from long-term physical activity (e.g., Verburgh et al., 2014), especially when this involves high levels of cognitive engagement. For example, a physical education program based on floorball and basketball with high levels of physical exertion and cognitive engagement enhanced elementary students' executive functions more than an aerobic program and the control condition (Schmidt et al., 2015). Moreover, a 6-month physical education program including cognitively demanding activities in tennis resulted in higher inhibition (Crova et al., 2014) and a sport program enriched with cognitive stimuli had positive effects on students' working memory and cognitive flexibility (Gentile et al., 2020).
Research has also focused on the acute effects of physical activity on students' executive functions in the context of physical education (e.g., Jager et al., 2014;Pesce et al., 2009). For example, a 30-min aerobic exercise session improved seventh-grade students' executive functions (Kubesch et al., 2009), while a 60-min game-based (i.e., basketball) activity enhanced students' executive functions, an effect particularly evident in fitter adolescents (Cooper et al., 2018). Jager et al. (2014) found that a 20-min sport sequence including cognitively engaging and playful forms of physical activity had positive effects on students' inhibition but not on updating and shifting. Moreover, Pirrie and Lodewyk (2012) found that a 20-min of moderate-tovigorous physical activity session within a 45-min physical education lesson, compared to a passive control group, enhanced students' cognitive process of planning but not those of attention, simultaneous processing, and successive processing. However, an acute cognitively engaging physical activity session did not affect students' executive functions (Bedard et al., 2021). Mixed evidence, regarding the acute effects of physical activity on students' executive functions, has also been provided by a recent systematic review (Paschen et al., 2019). Moreover, another systematic review reported that there is currently inconclusive evidence for the beneficial effects of physical activity interventions on cognitive and overall academic performance in children and called for further high-quality research in this domain (Singh et al., 2018).
One area that needs further investigation is which types of physical activity have the highest impact on students' cognitive development (Diamond & Ling, 2020). Cognitively challenging physical activity games is a promising means for developing students' executive functions, because they engage students in unpredictable, changing, and complex conditions and provide space for adaptations and exploration about how to play the game or what strategies to apply (Tomporowski et al., 2015). Indeed, executive functions are optimally developed when students are involved in cognitively complex physical activity experiences (Schmidt et al., 2015) and in novel, challenging, diversified but not highly repetitive and automatized tasks (Pesce et al., 2016). Most importantly, the focus of cognitively challenging games is not on performance but rather on providing students with opportunities to learn while having fun (Tomporowski et al., 2015).
Three types of cognitively challenging physical activity games can be designed following three principles of mental engagement, namely, highlighting contextual interference, emphasizing mental control, and promoting discovery (Tomporowski et al., 2015). Contextual interference is created when the context and the conditions of a game change requiring students to make unpredictable sequences of actions. Under nonrepeating, random game conditions (i.e., contextual interference) and alternating between action plans, students elaborate and think deeply about the features of the game and memorize better the requirements of the various movement plans. At the same time, they put more mental effort to reconstruct and plan multiple mental operations prior to action because the conditions of the game have changed. Mental control is based on the executive functions of response inhibition (stopping), working memory (updating) and mental shifting (switching) and can be developed with stopping games (students must react in alternating signals to go and stop overriding prior actions), updating games (memory demands for holding and manipulating information are required), and switching games (students must stop what they are doing and act in a totally different way). Discovery is promoted when the approaches of divergent discovery (multiple solutions to a problem) and open-ended games (the starting point, the rules, and the goal are explained, but not how to perform the game) are used (Tomporowski et al., 2015). These physical activity games can involve students in physical activity that is not only physically effortful, but also cognitively, emotionally, and socially engaging (Diamond & Ling, 2016).

The present study
Designing high-quality physical education programs for increasing students' physical activity but not at the expense of skill development is the cornerstone of a comprehensive school effort to increase students' physical activity levels (Rink et al., 2010). Focusing narrowly on either cognitive stimulation or physical activity in isolation may not be as effective as addressing jointly cognitive, physical and social development (Diamond & Lee, 2011). Thus, physical activity interventions should involve a holistic approach pursuing multiple objectives for students' physical and mental development (Tomporowski et al., 2011). Although this new approach seems promising, further empirical evidence regarding its effectiveness is warranted (Pesce, 2012;Pesce et al., 2018). Therefore, following a recent call for exploring further the beneficial effects of physical activity interventions on children's cognitive performance (Singh et al., 2018), the present study examined the acute effects of cognitively challenging physical activity games on students' executive functions. The characteristics of physical activity, such as the level of cognitive engagement during play or exercise, may affect students' executive functions (Pesce, Ballester et al., 2021). The cognitively challenging physical activity games, that adopt the approach of "moving with thought and fun", seem to be suitable for developing students' physical and motor coordination (Pesce et al., 2018) as well as their executive functions because they involve them in unpredictable conditions which set challenges and mental demands and require problem solving (Tomporowski et al., 2011). Undoubtedly, further empirical evidence regarding the effectiveness of these type of games is warranted. In the present study, three types of physical activity games were included. These were based on the three principles of mental engagement (i.e., highlighting contextual interference, emphasizing mental control, and promoting discovery; Tomporowski et al., 2015). To the best of our knowledge, there is no evidence regarding potential differences in the effects of these three types of physical activity games on students' executive functions. Such evidence will inform the discussion regarding the types of physical activity that are more beneficial for enhancing students' executive functions (Diamond & Ling, 2020) and may guide the designof effective physical education programs targeting students' physical and cognitive development in a holistic manner (Pesce, 2012).
Physical education programs should also enhance students' motivation is associated with positive outcomes including increased levels of physical activity out of school (Ntoumanis, 2001). Situational interest, which is defined as "the appealing effect of the characteristics of an activity on individuals" (A. Chen et al., 2006, p. 237), is viewed as a major motivational variable in physical education (Renninger & Hidi, 2016;Roure & Pasco, 2018). Thus, for enhancing students' motivation, the movement skills should be taught through enjoyable and interesting activities and games (Corbin & Pangrazi, 2003). From the students' perspective, perceived benefits of physical activity participation are centered on fun, achievement, and physical-related factors (Hohepa et al., 2006). Cognitively enriched physical activity games may offer students an attractive, challenging, and enjoyable means of being involved in physical activity, triggering their executive functions, and learning while having fun. Thus, to explore this potential, the present study examined the effects of the physical activity games on students' situational interest. Moreover, to increase the ecological validity of the results, this research was conducted in real-life physical education settings.
The aim of this study was to compare the effects of three different types of physical activity games (based on three different principles of mental engagement: contextual interference, mental control, and discovery) on students' executive functions and situational interest. It was hypothesized that the three groups of students with different types of physical activity games would outperform control group students on executive functions' measures. Due to the lack of previous evidence, no specific hypothesis was formed for the comparisons between the three groups with different types of physical activity games regarding their effects on students' executive functions and situational interest.

Design
A group-randomized controlled trial design was used in this acute experiment involving pre-and post-test measures for executive functions and a post-test measure for situational interest. Three experimental groups: a) Group 1 with physical activity games highlighting contextual interference, b) Group 2 with physical activity games highlighting mental control, c) Group 3 with physical activity games highlighting discovery, and a control group d) Group 4, without physical education were involved.

Participants and settings
Participants were 140 students (Mage = 10.97, SD = 0.51, 71 boys, 69 girls) from four fourth-grade (69 students) and four fifth-grade (71 students) classes of four elementary schools. One fourthand one fifth-grade class from each school were randomly assigned to each of the four groups of the study. Group 1 consisted of 29 students (13 boys, 16 girls), Group 2 of 36 students (16 boys, 20 girls), Group 3 of 36 students (18 boys, 18 girls), and Group 4 of 39 students (24 boys, 15 girls).
The schools recruited for this study were typical Greek civil schools with typical sport facilities including a basketball and a volleyball outdoor court and a school yard for other sport activities. Physical education in Greece is coeducational, mandatory, and it is delivered by specialized physical education teachers in three 45-min sessions per week for fourth-grade students and two 45-min sessions per week for fifth-grade students. The physical education curriculum for grades 4 and 5 includes the main team (i.e., basketball, volleyball, soccer, and handball) and individual sports (i.e., track and field and gymnastics) and traditional dance.

The design fluency test
Students' executive functions were measured with the design fluency test (Delis et al., 2001). This test assessed students' ability to draw as many different designs as possible in a predefined time (i.e., 60 seconds) generating novel designs by connecting dots with a pencil using four consecutive straight lines as quickly as possible while avoiding repeated patterns. The test included three conditions and a sheet with 35 square boxes with unstructured arrays of dots was used in each condition. In condition 1, each box contained five solid dots and students had to generate as many novel designs as possible using four consecutive straight lines. In condition 2, each box contained five solid and five blank dots and students had to generate as many novel designs as possible using four consecutive straight lines connecting only blank dots. In condition 3, each box contained five solid and five blank dots and students had to generate as many novel designs as possible using four consecutive straight lines alternating between connecting a solid and a blank dot (in each design they could start either from a solid or a blank dot). The number of correct and unique designs was students' score in each condition of the test. The first condition measures design fluency, the second condition additionally measures response inhibition, and the third condition measures the generation of novel designs while switching (cognitive flexibility). A total score combining the scores in the three conditions was also calculated (Delis et al., 2001).

Situational interest
The situational interest scale (Roure et al., 2016) was used to measure students' situational interest during the physical education sessions in the three experimental conditions with the physical activity games. This 19-item scale includes five situational interest dimensions with three items each: novelty (e.g., "what we did today was new to me"); instant enjoyment (e.g., "what we did today was enjoyable for me"); exploration intention (e.g., "I wanted to analyse and have a better handle on what we were learning today"); attention demand (e.g., "I was concentrated on what we were learning"); and challenge (e.g., "what we were learning was complicated"). Moreover, an overall subscale with four items is also included (e.g., "what we were learning today looks fun to me"). All items were rated on a 5-point Likert scale ranging from 1 (strongly disagree) to 5 (strongly agree).
A Greek version of this scale was developed and its psychometric properties were examined. In particular, the original items were translated into Greek by the authors and back-translated by two other bilingual persons. The back-translated questionnaire was compared to the original and minor modifications were applied. The resulting items were given to two fourth-and two fifthgrade students to comment regarding item comprehension. This version of the questionnaire was administrated to a pilot sample of 35 fourth-and fifth-grade students (Mage = 10.93, SD = 0.60, 18 boys, 17 girls) and the internal consistency (Cronbach's alpha) of the subscales were calculated. Based on these results, revisions in the items were made where considered appropriate. After these modifications, the resulting items were given again to another two fourth-and two fifth-grade students to comment regarding item comprehension and some final minor modifications were applied. Next, a confirmatory factor analysis on the data of a second pilot sample of 141 fourth-and fifth-grade students (Mage = 10.28, SD = 0.61, 69 boys, 72 girls) was performed. Based on the original version of the scale, a sixth-factor structure solution was tested. Considering that the pilot data exhibited multivariate kurtosis (Mardia's normalized estimate = 22.83) reported values of the fit indices were estimated using the robust method (Bentler, 2006;Satorra & Bentler, 1994). Confirmatory factor analysis showed an adequate model fit of the sixth-factor solution, χ 2 (137) = 159.82, p = .088, χ 2 /df = 1.17, NNFI = .980, CFI = .984, RMSEA = .034 (90% CI: .000-.055). The CFI and NNFI indexes exceeded the .90 and RMSEA value was below .05 criterions indicating an adequate overall fit of the model to the data (Hu & Bentler, 1999). All items loaded on their designated factors (range .47-.97, average factor loadings: .77). Satisfactory internal consistency (Cronbach's alpha) was also found for novelty (.94), instant enjoyment (.84), exploration intention (.82), attention demand (.72), challenge (.69), and total interest (.88).

Procedures
Ethical approval for the study was granted by the Ministry of Education and the University Ethics Review Committee. Permissions were also obtained from the school principals and the physical education teachers. Students participated voluntarily after a parental consent was obtained and they were told that the purpose of the study was to test new physical activity games. All sessions were conducted in the schools' open sport facilities during regular physical education hours by an experimenter blind to the aims of the study who was a physical education teacher with a master's degree in physical education and experienced in implementing physical education interventions.
One week before the acute experiment, students of the three experimental groups completed the design fluency test in their classrooms. For each condition of the test, they were provided with the respective instructions and they observed the experimenter to perform one trial on the classroom blackboard. Before each condition students performed a trial including three boxes of dots. Then, students completed each condition of the test. After participating in the physical education session with the physical activity games students of each group were post-tested in the design fluency test following the procedures used in the pre-test and completed the situational interest questionnaire. Control group students were pre-and post-tested in the design fluency test 1 week apart in days without physical education in their school schedule.

Description of the experimental conditions
The acute experiment for Groups 1, 2, and 3 involved a single 45-min physical education session and included 5-6 physical activity games. The characteristics of the physical activity games included in the session of each group are described next.
Group 1 students were involved in physical activity games highlighting contextual interference. In this type of games contextual interference is created, that is the context and the conditions of the game change continuously during the game requiring students to make unpredictable sequences of actions. Hop, pop, and tag is an example game falling in this type of games. This is a tag game played in open space and any student can tag any other student. When a student is tagged, he or she should squat down and can be back into the game when his/her tagger is tagged by another student. This game is different from traditional tag games challenging students to avoid being tagged by multiple taggers while they should tag the other students. Moreover, tagged students should be aware if their taggers are tagged in order to return back into the game (Tomporowski et al., 2015).
Group 2 students were involved in physical activity games highlighting mental control. This type of games includes stopping games which require students to react in alternating signals to go and stop overriding prior actions, updating games which set memory demands for holding and manipulating information, and switching games which requires students to stop what they are doing and act in a totally different way (Tomporowski et al., 2015). An example is an adaptation of a crazy traffic lights activity. In this activity students should follow the instructions of the physical educator and perform the action asked. The instructions may be given orally (e.g., three steps front), using numbers (e.g., 1: move forward, 2: move back, 3: move right, 4: move left), using colored cards (each color representing specific movement), or a combination of this approaches. The physical educator starts with simple and easy tasks and gradually uses more complex and longer sequence of actions. Moreover, interference is introduced. That is, two contradictory signals presented to students (e.g., an oral signal for moving forward and colored card for moving back) who should perform the action according to the predefined signal (e.g., colored card). This activity sets challenges to students to react appropriately to alternating signals and memory demands for holding and manipulating information when long sequence of actions is required.
Group 3 students were involved in physical activity games highlighting discovery. This type of games requires finding multiple solutions in problem solving conditions or in open-ended games, that is, games that the starting point, the rules, and the goal are explained, but not how to perform the game or what strategies to use (Tomporowski et al., 2015). An example is the speedy swappers. In this game, four students stand in the corners of a square and one in the middle. With the signal of the physical educator, the students in the corners (two each time) should swap positions along the perimeter, while the middle student tries to take over either open position. The aim of the outer students is to make five consecutive swaps. This game challenges students (both outer and middle) to find multiple effective strategies for being successful in their trials.

Statistical analyses
Pre-test differences in students' scores in the three conditions of the design fluency test between groups and between grades and gender were examined through an one-way MANOVA and 2 (Grade) × 2 (Gender) MANOVA, respectively. To examine the effects of the different types of games, a 4 (Group) × 2 (Time) repeated measures MANOVA with Group as the independent variable, Time as the repeated measure and students' scores in the three conditions of the design fluency test as dependent variables was conducted, followed by univariate analysis separate for each test condition and pre-to post-test comparisons within each group. Moreover, a 4 (Group) × 2 (Time) repeated measures ANOVA with Group as the independent variable, Time as the repeated measure and students' total score on the design fluency test as the dependent variable, was conducted. An one-way MANOVA with Group as independent variable and students' scores on the six subscales of the situational interest questionnaire as dependent variables was conducted for examining the effects of the three different types of physical activity games on students' situational interest. Effects sizes of partial η 2 and Cohen's d were also calculated (Cohen, 1988).

Preliminary analysis
Based on the criterion of less than ±1.96 for skewness and kurtosis after they have been divided by their respective standard errors, which is considered reflecting normally distributed data (Field, 2005), all pre-and post-test data for the three conditions and the total score of the design fluency test were normally distributed. A small deviation from this criterion was detected for some subscales of the situational interest questionnaire (i.e., total interest, challenge, and attention).
Means and standard deviations for students' pre-and post-test scores in the three conditions and the total score in the design fluency test, for each group, are presented in Table 1. Means and standard deviations for students' post-test scores in the six subscales of the situational interest questionnaire, for each group and correlations among the subscales in the total sample are presented in Table 2.
Regarding the effects of the three types of physical activity games on students' total score in the design fluency test, the 4 (Group) × 2 (Time) ANOVA with repeated measures on the last factor and students' total score in the design fluency test as the dependent variable, showed a significant Group × Time interaction, F (3, 136) = 19.06, p < .001, η 2 = .30. Follow-up comparisons showed significant improvements in the total score of the design fluency test from pre-to post-test for Group 1, t (28) = 8.83, p < .001, d = 1.15, Group 2, t (35) = 10.00, p < .001, d = 1.12, and Group 3, t (35) = 9.38, p < .001, d = 1.10, while no difference from pre-to post-test was found for control group students, t (38) = 1.14, p = .26.

Effects on situational interest
A MANOVA showed nonsignificant differences, F (12, 186) = 1.48, p = .14, between the three experimental groups on students' scores in the six subscales of the situational interest questionnaire.

Discussion
The present study adopted the approach of "moving with thought and fun" for promoting students' physical activity and triggering their executive functions. In particular, the effects of three different types of cognitively challenging physical activity games on students' executive functions and situational interest were explored. The results showed positive effects of these games on students' executive functions. No differences were found on executive functions and situational interest between the three experimental groups with the different types of physical activity games. These results are presented next in detail and are discussed with reference to previous respective research and empirical and theoretical evidence regarding the role of physical education in enhancing students' physical and cognitive development.
Students who participated in a single physical education session with cognitively challenging physical activity games improved their executive functions from pre-to post-test and outperformed control group students who were not involved in a physical education session in the testing days. In particular, the positive effects of physical activity games were found for all three conditions of the design fluency test used for measuring students' executive functions and the total score calculated as the sum of the scores in the three test conditions. Moreover, considering the effect sizes of the improvements from pre-to post-test for the three groups, the effects on students' executive functions can be considered high.
These results are consistent with previous research in physical education showing that acute physical activity interventions can enhance students' executive functions (e.g., Jager et al., 2014;Kubesch et al., 2009). Moreover, this is the first study, to our best knowledge, showing that an acute bout of cognitively challenging physical activity games can have positive effects on students' executive functions. Most importantly, the positive effects of the physical activity games on students' executive functions were generally large in size and resulted after students participated in a single physical education session. This is consistent with previous findings showing that even single sessions of physical activity, including 60-min game-based (i.e., basketball) activity (Cooper et al., 2018) or a 20-min sport sequence with cognitively engaging and playful forms of physical activity, had positive effects on students' executive functions (Jager et al., 2014). However, considering that mixed results regarding the acute effects of physical activity on students' executive functions have also been reported (Paschen et al., 2019), possible differences on the effects of typical repetitive types of physical activity versus cognitively challenging physical activity games on students' executive functions have yet to be examined.
For explaining the positive effects of the physical activity games on students' executive functions one can consider the characteristics of these games. In particular, cognitively challenging physical activity games emphasize variability of practice (Pesce et al., 2019) and involve students in unpredictable conditions requiring problem solving and mental engagement (Tomporowski et al., 2011). Moreover, these games set challenges to students by adding movements or increasing their coordinative difficulty, altering the rules to make the game more challenging, changing game intensity or duration, or both, altering the roles of students during the game, and shifting the .32* *Significant correlation (p < .01) structure of the game to encourage problem solving and divergent discovery (Pesce, 2012). All these game conditions can facilitate students' cognitive development. Indeed, executive functions are optimally developed when students are involved in cognitively complex physical activity experiences including novel, challenging, diversified but not highly repetitive and automatized tasks (Pesce et al., 2016;Schmidt et al., 2015).
The results of this study also suggested that all three types of physical activity games based on the three principles of mental engagement (i.e., contextual interference, mental control, and promoting discovery; Tomporowski et al., 2015) were equally effective, compared to the control group, in enhancing students' executive functions. This is an interesting result suggesting that the unique characteristics of each type of cognitively challenging physical activity games can challenge students' executive functions. That is, each one of the three principles of mental engagement used for designing these games can be considered effective in creating appropriate conditions for triggering students' executive functions. In particular, the physical activity games highlighting contextual interference involve students in nonrepeating, changing and random game conditions requiring them to make unpredictable sequences of actions. These conditions force students to elaborate and think deeply about the features of the game, to memorize better the requirements of the various movement plans and to put much more mental effort for reconstructing and planning multiple mental operations during the game (Tomporowski et al., 2010). The physical activity games highlighting mental control involve students in reacting in alternating signals to go and stop overriding prior actions, in holding and manipulating information regarding the appropriate movements needed, and in stopping what they are doing to act in a totally different way. These conditions trigger students' executive functions of response inhibition, working memory, and cognitive flexibility (Diamond, 2015). The physical activity games highlighting discovery involve students in providing multiple solutions to a problem and to open-ended games and allow for several options strategies to be used (Tomporowski et al., 2015). Such conditions provide students with the flexibility to shift their attention between the demands of the task, to change their perspectives or approaches to solve a problem, and to put high levels of mental effort which are closely linked with the development of the cognitive flexibility. However, all these interpretations need empirical support from research exploring further the underlying mechanisms of the effects of each type of the cognitively challenging physical activity games on students' executive functions.
Regarding the effects of the physical activity games on situational interest, the results of this study showed nonsignificant differences between the three groups with different types of physical activity games on students' scores in the six subscales of the situational interest questionnaire. Generally, students of all three groups scored high in the four out of six subscales of the situational interest questionnaire. In particular, students' scores were above the middle of the scale in all subscales with the exception of their scores in novelty that lied in the middle point of the scale and in challenge that were below the middle of the scale. These scores suggest that physical activity games had appealing features attracting students' situational interest (A. Chen et al., 2006). Indeed, students may enjoy their involvement in the physical activity games, were cognitively concentrated and put mental energy and was triggered to explore and discover new movement patterns during the games (S. Chen et al., 2014). These results are important because instant enjoyment is considered a powerful source of motivation representing a key factor underlying students' motivation for maintaining positive engagement in physical education (Grasten et al., 2012;Roure & Pasco, 2018). That is, appropriately designed physical activity games can offer students an attractive, cognitively demanding, and enjoyable means of involving in physical activity, triggering their executive functions, and learn while having fun. This is an important aspect of the physical activity games because it is consistent with students' views that the perceived benefits of physical activity participation are centered on fun, achievement, and physical-related factors (Hohepa et al., 2006). Indeed, fun and enjoyment is considered major motivators for engaging in physical activity among adolescents and adults (Bragg et al., 2009).
The moderate levels of novelty reported by students may be explained by the fact that students were familiar with some of the physical activity games included in each group. Actually, some of the physical activity games were known to students but they were modified to become more cognitively challenging. For example, although students are familiar with tag games, the tag game used in this study (i.e., hop, pop, and tag) included characteristics that challenged students' cognitive engagement. Despite this, students' scores in novelty were in the midpoint of the scale indicating that students acknowledged some innovative aspects in these physical activity games. Moreover, students reported low levels of challenge for the physical activity games. Considering that challenge is defined as the level of difficulty relative to one's ability (S. Chen et al., 2014) students may perceive that the physical activity games were not so difficult for them to participate successfully. However, it should be considered that usually students overestimate their performance in physical education (e.g., Kolovelonis & Goudas, 2018. Generally, challenge should be at an optimal level (not too difficult or too easy) for motivating students but not frustrating and therefore decreasing their enjoyment from participating in the tasks (Roure & Pasco, 2018).
The present acute experiment which was conducted in authentic learning environments provided evidence for the positive role that physical education can play on enhancing students' cognitive development. The result of the present study provided support to the new approach of shifting "from simply moving to moving with thought" (Diamond, 2015, p. 1) suggesting that physical activity programs should focus both on health-related outcomes and energy expenditure and cognitive development (Pesce et al., 2018). All three types of cognitively challenging physical activity games involved students in physical activity tasks triggering their cognitive functions and keeping their situational interest for participating in these games generally high. Thus, these games may be considered appropriate for promoting a holistic approach for students' development, meeting multiple objectives such as physical and mental development (Tomporowski et al., 2011).
The results of the present study can inform practical implications for physical education and good practices in designing effective physical education programs targeting students' physical and cognitive development in a holistic manner (Schmidt et al., 2015). The physical activity games are considered an appropriate content for meeting physical education standards and goals, such as achieving and maintaining a health-enhancing level of physical activity and fitness and promoting self-expression, enjoyment and cognitive development (e.g., American Alliance for Health, Physical Education, Recreation and Dance, 2013). Traditional forms of physical activity tasks may be not so appealing for many students and thus, some students may be reluctant to participate in physical activity tasks (Dalle Grave et al., 2011). For overcoming this issue, physical educators should consider involving in their programs cognitively challenging physical activity games. These games have the advantage of involving students in attractive and enjoyable forms of physical activity, triggering at the same time their executive functions (Tomporowski et al., 2015). Considering that all types of cognitively challenging physical activity games had a significant impact on students' executive functions, physical education programs may include a combination of the three types of these games. Physical educators may select the types of the games based on the specific characteristics of each type of game and how these fit to the learning objectives of each session. Moreover, physical educators can adapt the physical activity tasks or games that are usually used during physical education to make them more challenging and cognitive demanding for their students. The three principles of highlighting contextual interference, emphasizing mental control, and promoting discovery (Tomporowski et al., 2015) can be used as a guide in this process. Moreover, physical educators should design physical activity tasks requiring from students to be active and to make frequent problem-solving decisions (Tomporowski et al., 2010). Physical educators may also consider involving their students in the process of adopting and creating their own cognitively challenging physical activity games.
Limitations of this study should be acknowledged. Considering that the main aim of this study was to compare the three types of cognitively challenging physical activity games, a passive control group (i.e., without physical education in testing days) was involved. This approach has also been used in previous research examining the effects of physical activity programs on participants' executive functions (e.g., Jager et al., 2014;Pirrie & Lodewyk, 2012). Future research should also compare the effects of these games with the effects of other physical activity tasks (e.g., regular routines for physical activity) or other types of physical education content (e.g., teaching skills of team or individual sport) on students' executive functions. Such research should also examine the effects of the combined use of the three types of physical activity games in a single physical education session. The use of a single measure for measuring students' executive functions may also be considered as a limitation of this study. However, this approach was used for measuring students' executive functions immediately after the acute intervention in order to minimize confounding effects of elapsed time or other confound variables after the implementation of the games.
Although the present study showed that all three types of cognitively challenging games were equally effective on triggering students' executive functions, future research should further explore this issue involving a variety of tests for measuring executive functions as well as other related variables (e.g., motor coordination, motor creativity). Moreover, future research should examine the effectiveness of long-term interventions including a large number of physical education sessions consisted of cognitively challenging physical activity games. Such research may also examine the retention of the effects of these games and their effects on other related variables, such as students' self-efficacy, their motivation for participating in physical education or their intentions for participating in physical activity out of school. The physical activity games can increase students' levels of physical activity during physical education session. However, this study did not involve a measure of students' physical activity. Thus, future research should measure the amounts of students' physical activity when playing these games and examine if the amount of the physical activity spent during the physical education session is associated with students' executive functions.