1 Background

During childhood, there are considerable benefits to be gained from appropriate physical activity (PA), such as promoting physical growth and development, improving academic performance, sharpening willpower, and developing interpersonal communication skills [1–3]. However, in many countries, less than 40% of children are able to achieve the level of PA needed to maintain optimal health daily [4], and in some studies, this figure reaches a staggering 20% [5, 6], which means that worldwide, 8 out of 10 children are physically inactive. Physical inactivity has become one of the most critical factors contributing to life-threatening non-communicable diseases globally [7]. Inadequate PA is not only a serious threat to physical and mental health (e.g., obesity, hypertension, depression, etc.) but also a severe economic cost. For example, physical inactivity costs Australia $13 billion annually in financial losses, including medical expenses, loss of workforce, and premature death [8]. Although PA generally shows a downward trend throughout an individual’s entire life journey, if good and sufficient PA is carried out and maintained during childhood, it can delay the time when they become inactive [9] and prevent the development of harmful habits in the future, such as smoking, etc. [10]. Therefore, there is a growing call for children to become physically active, and it is urgent to make every effort to encourage children to participate in and maintain lifelong PA.

Physical literacy (PL), developed by Whitehead, is currently an effective underlying theory for encouraging lifelong PA participation [11, 12]. Since the concept was first introduced, it has attracted widespread scholarly attention worldwide [13]. The concept of PL has always been controversial and not unified; multiple scholars have attempted to define it [14–17]. However, the concept defined by Whitehead is widely accepted by the global academic community [17]. Whitehead defined physical literacy as "the motivation, confidence, physical competence, knowledge and understanding to maintain physical activity throughout the life course" [18]. The concept encompasses the affective, cognitive, and physical domains and is based on three main philosophical ideas: existentialism, monism, and phenomenology. These philosophical ideas are intertwined and reveal the true nature of PL by documenting an individual’s PA as it interacts with the world [19, 20].

Scholars and educational institutions around the world have recognized that PL is just as crucial as the educational value of literacy and numeracy [21, 22]. Meanwhile, Whitehead described the relationship between PL and PE, stating that PL is the ultimate goal of PE, and PE is the main means to achieve PL [23]. The concept of PL provides direction for active learning by students, active teaching by PE teachers, and active support and PE curriculum development by schools and governments. Therefore, PL is now integrated into physical education (PE) policies worldwide. For example, UNESCO’s QPE (Quality Physical Education) guidelines for PE policymakers use PL as a conceptual basis [24]. Subsequently, many countries or regions responded by setting PL as the target of PE. For example, SHAPE (Society of Health and Physical Educators) America’s third edition of the National Standards for K-12 Physical Education uses the term "physical literacy" instead of "physically educated" [25]. In the Chinese mainland, the government issued a school PE policy in 2016 that explicitly emphasizes the need to improve students’ PL [26]. In Hong Kong and Taiwan, PL was also introduced in the relevant policies [27]. The Australian Sports Commission has also developed PL standards applicable to their country [8]. Some countries in Europe are also working to integrate PL and PE. For example, PL has been included in the new 2021 curriculum for all ages in Greece, this concept has also been adopted in school sports in Denmark [28]. The majority of children’s time is devoted to being in school, so school is seen as the most essential and critical place for developing children’s and youths’ physical and mental health [29]. Adequate sports facilities, a positive PA climate, and a supportive school PA policy all have an impact on students’ active participation in PA and enhance their PL [30–32]. The most critical link, however, is the PE teacher. School PE policies need PE teachers to respond, PE classrooms need PE teachers to lead, and extracurricular PA needs PE teachers to guide. Everything that creates a connection with PA and PE activities within the school is inseparable from PE teachers. Meanwhile, PE teachers have a unique role because, when students are in school, they can have a direct positive impact on students’ physical learning and PA [33], which other subject teachers cannot do. Most importantly, the ultimate goal of PE is PL [34]. To pass on the various outcomes contained in PL to students and enable them to have PL, it is necessary to require PE teachers to understand PL, have PL as well as implement PL in PE [18]. In summary, promoting PL among PE teachers can be recognized as a key opportunity to bring significant health benefits to students [23]. However, many current studies have focused on children, children with disabilities, and older adults. This situation makes it particularly important to review the PL levels of PE teachers and to assess and develop PL among them.

This study aims to: first, systematically review the literature involving PE teachers’ PL levels and analyze current PE teachers’ PL levels and strategies for improving them. Second, find and critically evaluate assessment tools that have been used to assess PL levels of PE teachers in the current studies and to offer appropriate recommendations for future development of relevant tools.

2 Methods

This review strictly follows the reporting checklist of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) systematic evaluation guidelines [35]. PRISMA guidelines is a complete, rigorous, and credible tool, which are becoming more and more indispensable, especially in health-related fields [36]. A protocol was set in advance to improve the inclusion criteria and make the search for literature more comprehensive. Therefore, a search strategy was developed that can retrieve relevant studies with key terms appearing in the title, abstract, and keywords. Six databases were used for the literature search: (1) Web of Science; (2) Scopus; (3) ScienceDirect; (4) PubMed; (5) ProQuest; and (6) SportDiscus. These electronic databases encompass research related to exercise and health, which increases the likelihood that relevant studies will be retrieved and included. The Boolean logic operators were used in the electronic databases, with the search term "physical literacy" AND (teacher OR educator OR instructor OR schoolteacher OR lecturer OR coach OR mentor OR tutor). The term "physical literacy" is enclosed in double quotes to ensure that the search is for articles related to physical literacy, not "physical" or "literacy." Two systematic reviews [17, 37] that have had a profound impact on PL research guided the development of the protocol. The last search was conducted on April 3, 2023.

The criteria that can be included in this systematic review are (1) peer-reviewed publications, and (2) English publications. In order to meet the purpose of this study and address research questions, the exclusion criteria are as follows: (1) The research subject is not a physical education teacher; (2) The assessment method of PL (qualitative or quantitative) is not been reported; (3) book chapters and book reviews; (4) conference papers and readings; (5) theses or dissertations; (6) editorials and forewords; (7) not accessible in full text.

The filtering results from all databases were imported into Excel software. After removing duplicate literature, two reviewers (YH and LF) independently conducted literature screening to evaluate whether these articles met the inclusion and exclusion criteria based on the title, abstract, and keywords. Subsequently, conduct a full-text review of the remaining articles. Any disputes or discrepancies between the two reviewers were resolved through discussion with the third reviewer (LM), and a consensus was reached that 8 articles met the criteria. Fig 1 shows the inclusion and exclusion of literature at each stage.

Download:

• PPT
  PowerPoint slide
• PNG
  larger image
• TIFF
  original image

Fig 1. PRISMA flow diagram showing the process of study identification and selection [36].

https://doi.org/10.1371/journal.pone.0307505.g001

3 Results

3.1 Summary of studies

After identification and screening, only 8 articles out of 671 retrieved from the database finally met the preset eligibility criteria (for the detailed process, see Fig 1). Table 1 shows an overview of the included studies.

Download:

• PPT
  PowerPoint slide
• PNG
  larger image
• TIFF
  original image

Table 1. Summary of studies.

https://doi.org/10.1371/journal.pone.0307505.t001

3.2 Characteristics of studies and participants

The characteristics of the included studies are shown in Tables 2 and 3. There are not many studies on the PL of PE teachers, and they are concentrated in developed countries or regions with better economic development, all of which have been conducted in recent years. The population mainly consists of PE teachers of children and adolescents and also includes pre-service teachers (individuals who are pursuing PE with the intention of becoming licensed teachers). The age of the population mainly ranges from young to middle-aged.

Download:

• PPT
  PowerPoint slide
• PNG
  larger image
• TIFF
  original image

Table 2. Study characteristics.

https://doi.org/10.1371/journal.pone.0307505.t002

Download:

• PPT
  PowerPoint slide
• PNG
  larger image
• TIFF
  original image

Table 3. Participants characteristics.

https://doi.org/10.1371/journal.pone.0307505.t003

3.3 Characteristics of assessment tools

Table 4 displays the assessment tools utilized in the studies incorporated in this review (tools whose names were not known were excluded). There were 12 instruments in total, including 7 developed in the United States, 4 developed in Canada, and 1 developed in Hong Kong. Among them, the Canadian Assessment of Physical Literacy (CAPL) measures four domains related to physical literacy: physical, cognitive, affective, and daily domain. The daily domain is measured through a pedometer and a self-reported questionnaire, which accounts for 32 points. The physical competence domain was measured by body composition (BMI and waist circumference), musculoskeletal fitness (grip, plank, flexibility), Progressive Aerobic Cardiovascular Endurance Run (PACER), and obstacle course, accounting for a total of 32 points. The cognitive and affective domains are both measured by questionnaires, each accounting for 18 points. The scores of the four domains are added together to obtain a total CAPL score (out of 100), and the total PL score is subsequently categorized into four levels: beginning, progressing, achieving, and excelling, depending on age and gender. In CAPL-2, the score for each domain has been changed to 30 points for the physical domain, 30 points for the daily domain, 30 points for the emotional domain, and 10 points for the cognitive domain. The physical competence domain is also simplified by removing the body composition test and retaining only the PACER, plank support, and CAMSA.

Download:

• PPT
  PowerPoint slide
• PNG
  larger image
• TIFF
  original image

Table 4. Characteristics of the assessment instruments involved in the included studies.

https://doi.org/10.1371/journal.pone.0307505.t004

In addition to CAPL and CAPL-2, there is also a tool that measures the physical domain: the TGMD-2(Test of Gross Motor Development, Second Edition). The TGMD-2 is a set of tests comprising two subtests: namely locomotor and object control, each designed to assess distinct aspects of gross motor development. The locomotor subtest evaluates skills related to movement and coordination, while the object control subtest focuses on skills involving the control and manipulation of objects. The TGMD-2 takes a process score, with the examiner scoring the test based on the subject’s performance. In addition, PSPP measures the self-perceived physical domain. There are five subscales, each with 6 items. A four-choice structured alternative format was selected for item design. Each scale has a maximum score of 24 and a minimum score of 6. This includes perceived sports competence, perceived physical strength and muscle development, as well as perceived level of physical conditioning and exercise.

As for cognitive and affective domains, all tests are measured using online or offline questionnaires. All questionnaires are scored on the Likert scale rating system. It is important to note that while most questionnaires measure only one of the affective or cognitive domains, the Perceived Physical Literacy Instrument (PPLI) assesses both affective and cognitive domains, as well as a third domain, communicative domain, using nine questions to assess three domains of physical education teachers’ self-perceived physical literacy: the sense of self and self-confidence, self-expression and communication with others, and knowledge and understanding. Again, a Likert scale was used, with 1 indicating strongly disagree, 5 indicating strongly agree, and 3 indicating neither agree nor disagree.

4 Discussion

Physical literacy as a comprehensive and holistic concept has inspired scholars to explore and practice this concept globally. This systematic review aims to identify instruments/tools for measuring PL among PE teachers, review the level of PL demonstrated by PE teachers in existing studies, analyze underlying factors, and provide recommendations for future research. While most previous systematic reviews on PL have focused on adolescent children, older adults, or children with disabilities, this review uniquely focuses on PE teachers. As far as our knowledge extends, this is the first comprehensive systematic review of PL specifically among PE teachers, encompassing 8 included Studies that highlight limited exploration in this area.

In the 8 included studies, a total of 12 distinct quantitative assessments were then confirmed for validity and reliability. Among these, only three instruments (CAPL-1, CAPL-2, and PPLI) explicitly measured PL levels, with the remaining instruments assessing only one aspect of PL. The CAPL-1 was developed in 2014 by HALO (The Health Active Living and Obesity Research) in Canada. HALO organization, and considering the low relevance of the four dimensions of the CAPL-1 assessment [74], HALO revised it to promulgate the CAPL-2 in 2017, which not only streamlines the items but also optimizes the operational difficulty and time-consuming, making it one of the most popular and highly reliable physical literacy assessment tools today and it has been translated into several versions and is widely used worldwide [46, 75]. Although the CAPL is very popular in the PL assessment area, it is necessary to clarify that the CAPL is designed to be used with 8–12 years old children. In the two studies that reached the inclusion criteria [38, 45], the subjects were pre-service teachers, and the instrument used was the CAPL, which clearly does not fit the age range to which the CAPL is applicable. Hence, the scientific rigor and accuracy of the findings in these studies require further verification.

Another assessment tool that can systematically assess teachers’ PL levels is the PPLI (Perceived Physical Literacy Instrument), an instrument developed by Sum et al. in 2016 specifically to assess PE teachers’ perceived PL levels and was validated to demonstrate strong reliability and validity, including three dimensions: "sense of self-confidence," "self-expression and communication with others," and "knowledge and understanding" [56]. The PPLI was further validated to be equally applicable to adolescents and older adults, with good reliability and validity [57, 76]. Then the PPLI has since been translated into multiple language versions for use in various countries [58–60]. However, one study has shown that PL’s behavioral, psychological, and physical competence is (theoretically and practically) distinct but interrelated and that a comprehensive assessment of the constructs can offer a more precise assessment of a person’s ability to perform PL. To fulfill the purpose of PL assessment, a suitable evaluation of physical skills is essential. [77], which aligns with the concept of PL defined by Whitehead [18]. Furthermore, it has been established that there is a difference between children’s perceived PL and actual PL [78]. In addition, it has also been noted that self-report-based tests of physical competence are not credible [79], so many researchers recommend the use of objective direct measures of physical competence [80]. Therefore, whether there is a difference between the perceived PL of PE teachers, as measured by the PPLI, and the actual PL of teachers needs to be confirmed in future studies.

Other PL assessment tools assess only one domain of PL. In other words, these assessment tools themselves were not developed to assess a person’s PL, only that what they assess happens to align with one or more domains of the PL definition, enabling indirect assessment of certain aspects of PL. For example, physical competence constitutes a crucial component of PL, and within the concept of PL, there is an overlap in meaning between physical competence and some of the terms commonly used in more established fields of current research, such as motor ability, motor control, motor skills, etc. [81–83], and the TGMD-2 included in this review assesses an individual’s motor skills. Meanwhile, due to the relative paucity of tools to assess PL, some researchers have used these tools to assess PL. Although researchers used assessment tools to measure the cognitive and affective domains in the included studies, the lack of a gold standard led to mixed results across assessments. This is because many different factors are included in the affective and cognitive domains. For example, the affective domain includes motivation, confidence, enjoyment, commitment, autonomy, and self-esteem; the cognitive domain includes the knowledge and understanding of the benefits of PA, the knowledge and understanding of the importance of PA, knowledge, and understanding of strategies, rules, and assessment of safety considerations and risks [84]. Moreover, the tools used in the included studies did not assess applied physical competence in different contexts or specific contextual knowledge focused focus on PA (e.g., strategies and organization) which are critical for PE teachers and align more closely with the definition of PL [85]. There are, of course, some valuable assessment tools. The BREQ-3 [50], for example, was developed using self-determination theory, widely recognized as a fundamental framework for comprehending motivation, not only in the context of sports but also more broadly in exercise and PA [85, 86].

This review also reviewed the PE teachers’ PL level in existing studies. Physical competence and level of daily PA were the areas of PL in which PE teachers (including pre-service PE teachers) performed poorly. Three studies [29, 32, 36] measured the physical competence of PE, and all three showed low levels of physical competence. Chen’s [38] findings indicate that pre-service PE teachers’ physical competence was, in some areas, inferior to that of a 12-year-old child. It is difficult for a PE teacher to serve as a teacher role model and for the PE teacher’s authority to be challenged if he or she is still inferior to a child as a responder to school PE policy, an implementer of PE, and a role model for children. In addition, given the unique nature of the role of PE teachers relative to teachers of other subjects, poor physical competence will directly affect the effectiveness of PE teaching as they are required to demonstrate some movements in the PE classes [18, 87, 88]. The reasons for the poor physical competence of PE teachers are multiple, including work ability [89], stress level [90], and lack of PE teacher development training [91], etc. In addition, aging is also a major factor affecting the physical competence of PE teachers, which can lead to the turnover or attrition of PE teachers [92]. Aging brings about a decline in physical competence and this process is irreversible. Nevertheless, PE teachers can exercise regularly to slow down this process [93, 94]. Conversely, PE teachers performed better in cognitive and affective than physical competence. The included studies showed moderate or high performance levels in the cognitive, and affective domains. This may be due to relevant courses taken during school years, current teacher development training, and accumulation of teaching work experience [44]. However, it should be noted that this study also takes pre-service teachers into account due to the limited number of included studies. The definition of pre-service teachers may vary from country to country, but they are still in the training stage and have not obtained a license or entered the workplace. Therefore, they are different from in-service teachers. The results of the included studies also show that there are differences between in-service teachers and pre-service teachers. Nonetheless, the results of this study are still applicable. Including pre-service teachers in the study can expand the research perspective, more comprehensively reflect the current situation and needs in the field of education, and better respond to future educational challenges.

Different groups have different feelings about PL and the content of PL. For PE teachers, the physical competence domain of PL includes their own athletic ability and physical health level that can support them in PE teaching activities, which is the foundation for a PE teacher. The affective domain includes the motivation and confidence of PE teachers to participate in PA and teaching activities, as well as the evaluation of their own and students’ various skills and abilities in PA and PE teaching activities, and communication and interaction with students. The perfect cooperation between PE teachers and students can lead to an excellent PE class. The cognitive domain includes PE teachers’ knowledge and understanding of PA and PE teaching activities, the ability to make informed decisions in the face of various emergencies, and how to adapt themselves and their students to various environments.

As mentioned before, the level of individual PL supports teaching ability in this area [39], and the level of PL also predicts the effectiveness of PE teaching [43]. Therefore, improving and maintaining a high level of PL among PE teachers is also a top priority in school PE. This is an issue that requires significant attention and action from educational policymakers. The teacher’s continuing professional development (CPD) is considered an effective way to improve the PL level of PE teachers. UNESCO’s guidelines for policymakers state that the CPD of teachers should be a priority for developing quality physical education(QPE) in each country [95]. There are already many countries where the CPD of teachers is a mandatory requirement for upholding teacher registration or maintaining teaching standards [96–98]. It has been established that the impact of teachers’ professional development on PE teachers’ PL is significant [44]. However, the content of teacher professional development programs will vary from country to country, with different cultural contexts and realities. Nevertheless, continuous professional development for teachers requires 1) attention to the complexity of the learning process, 2) prioritizing the context of the times and contemporary challenges, 3) integrating research/theory and practice in an innovative way, and 4) fostering the professional development of PE teachers [99]. Based on this, Sum et al. [100] developed PE-CPD specifically for PE teachers in Hong Kong by incorporating the concept of PL in the CPD. The study’s findings demonstrated a significant impact of customized PE-CPD on PE teachers’ beliefs concerning both perceived PL and teaching efficacy. The weakness is that there is a difference between actual PL and perceived PL. Also, with the rapid development of technology in the field of education, more CPD is now conducted in an online format [101, 102]. While online CPD can effectively improve physical literacy’s affective and cognitive domains for PE teachers, it is minimally helpful in their weakest domain, physical competence [103–105]. PL can be developed through PA, so it is necessary to include PA in CPD. Introducing PA as content to PE teachers also means that they can engage in the pursuit of PE [40]. Therefore, when developing CPD for PE teachers in the future, relevant policymakers should consider incorporating the relevant construct of PL, focusing on the overall development of PE teachers’ PL, selecting appropriate training content (e.g., sports with local characteristics, PE teaching methods that incorporate the concept of PL, knowledge of relevant content or relevant scenarios, etc.), and selecting appropriate training formats. (e.g., seminars, workshops, courses, etc.).

Overall, based on the included studies, our findings indicate that there is very little current research on PE teachers’ PL; only one instrument is available to assess PE teachers’ perceived PL, and there is no instrument available to assess PE teachers’ actual PL comprehensively. Moreover, the cognitive and affective of PE teachers are at moderate or high levels, and their physical competence is at a poor level. Future research on this topic could focus on developing tools that can be used to assess the actual PL of PE teachers systematically and comprehensively and how to improve the PL of PE teachers. In developing assessment tools, it is crucial to first unify the concept of PL within the PE teacher population, as the diversity of PL definitions can lead to confusion in PL assessment. Due to different definitions and philosophical underpinnings of PL, the components and methods of PL assessment are different [17, 77]. Indeed, the definition of PL is still a controversial topic [106], and the most widely accepted definition of PL is that of Whitehead [18], on which most PL assessment tools for children have been developed. However, the applicability of this definition to the PE teacher population, or the need to add additional elements, is a topic for future research. Secondly, the traditional/conventional, linear approach no longer meets the current needs of PL assessment [37], but rather an innovative, non-traditional approach should be used. For example, some argue that the results of evaluating PL should not be an intuitive reflection of the concept but rather suggest "charting" the progression of PL [107], which may be a normative and appropriate assessment method. Finally, existing assessment tools are deficient, and future tool development should take them into account. Ensuring that the assessment process is efficient and economical (human and material resources) and that the assessment results are scientific, valid, and accurate is essential. The CPD is an effective way to improve PE teachers’ PL. Future research on the CPD should consider the actual national context, cultural characteristics, governance structures, and the training courses’ novelty and challenge to increase PE teachers’ willingness to participate. Focus on the choice of training content and format to ensure that PE teachers who have participated in the CPD can effectively improve PL and can apply it to their daily PE teaching to enhance students’ PL.

This study has the following limitations: (1) Language bias: only papers published in English were retrieved. Therefore, studies on PL levels of PE teachers in non-English speaking countries may have been missed. (2) All retrieved articles were already published; therefore, some studies, such as the gray literature, may have been missed. (3) no qualitative assessments of physical education teachers’ physical literacy were found in the search results. If some specific qualitative methods (e.g., interviews, focus groups, etc.) were included in the search terms, the search results might contain some qualitative assessments. (4) The systematic review did not answer or present a concept about the PL of PE teachers, which may be considered a limitation.

5 Conclusion and implications

This study represents the first comprehensive paper that offers a systematic review of empirical research related to assessing or measuring PL among PE teachers. The current findings suggest that PE teachers perform poorly in the physical competence domain, and perform better in the cognitive and affective domains. However, there is insufficient literature to analyze the trend of PL among PE teachers.

Nonetheless, this study has important practical application value. First, identifying the deficiencies in the PL level of PE teachers can provide key data support for education departments and policymakers to help them formulate more targeted training and development plans. In particular, CPD programs are considered to be an effective means to improve PE teachers’ PL. By designing and implementing specialized CPD programs, the physical competence and overall PL level of PE teachers can be effectively improved.

Furthermore, there is currently only one assessment tool that can systematically measure PE teachers’ perceived PL (not actual PL); other studies have used instrumental components. This shows that there is an urgent need to develop more comprehensive and systematic assessment tools. These tools can not only help teachers self-assess and improve but also provide researchers with more reliable data to further promote the development of research and practice in the field of PL.

Therefore, future research should first attempt to define a unified concept of PL applicable to PE teachers and then develop tools that can comprehensively assess PL of PE teachers based on this concept. Furthermore, given the small number of studies that could be included at present, future research needs to expand the study criteria to include a wider population, such as teachers or general adults. This would provide a richer database, offer more reliable insights, and aid in the development of comprehensive assessment tools. Tool developers may consider combining qualitative or quantitative approaches in the future. In summary, the findings of this study provide an important reference for the future development of PL assessment tools and training programs for PE teachers, which will help improve the quality of PE and ultimately promote students’ participation in PA and the development of PL levels.

Supporting information