Physical activity (PA) decreases with age. The school transition is noted for significant changes in PA behaviour. Motor competence (MC), health-related fitness (HRF), and perceived competence (PC) are generally positively associated with PA. The aim of this study was to examine longitudinal cross-lagged relationships between PA, MC, HRF, and PC across the school transition from final year of primary school to first year of second-level school in Irish youth. PA (accelerometery), object-control and locomotor MC (TGMD-III), PC (perceived athletic competence subscale of the Self-Perception Profile for Adolescents), and HRF (20 m shuttle run, horizontal jump, vertical jump, push-ups, curl-ups) were measured in final year of primary school (6th class) and first year of second-level school (1st year). In the sixth class, 261 participants (53% female; mean age 12.22 ± 0.48 years) were tested. In first year, 291 participants (48% female; mean age: 13.20 ± 0.39 years) were tested. In total, 220 participants were involved in the study at both timepoints. Cross-lagged regression in AMOS23, using full information maximum likelihood estimation, was conducted to test reciprocal and predictive pathways between variables. The full cross-lagged model showed acceptable fit (χ² = 69.12, df = 8, p < 0.01, NFI = 0.93, CFI = 0.94). HRF was the strongest predictor of future PA (β = 0.353), and also predicted PC (β = 0.336) and MC (β = 0.163). Object-control MC predicted future PA (β = 0.192). Reciprocal relationships existed between object-control MC and PA, and between object-control MC and PC. HRF was the strongest predictor of PA. Object-control MC also predicted PA. PA promotion strategies should target the development of HRF and object-control MC in primary school to reduce the decline in PA frequently observed after the school transition.

Physical literacy provides a foundation for lifelong engagement in physical activity, resulting in positive health outcomes. Direct pathways between physical literacy and health have not yet been investigated thoroughly. Associations between physical literacy and well‐being in children ( n = 1073, mean age 10.86 ± 1.20 years) were analysed using machine learning. Motor competence (TGMD‐3 and BOT‐2) and health‐related fitness (PACER and plank) were assessed in the physical competence domain. Motivation (adapted‐Behavioural Regulation in Exercise Questionnaire) and confidence (modified‐Physical Activity Self‐Efficacy Scale) were assessed in the affective domain. Well‐being was measured using the KIDSCREEN‐27. Accuracy of predicting well‐being from physical literacy was investigated using five machine learning classifiers (decision tree, random forest, XGBoost, AdaBoost, k ‐nearest neighbour) in the full sample and across subgroups (sex, socioeconomic status [SES], age). XGBoost predicted well‐being from physical literacy with an accuracy of 87% in the full sample. Predictive accuracy was lowest in low SES participants. Contribution of physical literacy features differed substantially across subgroups. Physical literacy predicts well‐being in children but the relative contribution of physical literacy features to well‐being differs substantially between subgroups.

Health-related fitness (HRF) is theoretically defined as a multidimensional construct containing the components cardiorespiratory endurance, muscular strength, muscular endurance, flexibility and body composition. Given the range of field-based HRF tests available, health practitioners face a difficult task in selecting tests that best reflect the HRF construct as defined in the literature. This study aimed to investigate the underlying factor structure of the theoretical HRF construct with a view to identifying field-based tests representative of HRF in youth. Participants were 261 children (53% female, 47% male; mean age 12.22 ± 0.48 years). Indicators of four fitness components (20m shuttle run, curl-ups, push-ups, horizontal jump, vertical jump, handgrip, and modified back-saver sit-and-reach) were measured. Confirmatory factor analysis of the four-component model revealed a low contribution of flexibility (.10) to the overall model, leading to its removal. The subsequent three-component model showed better fit across all fit statistics (NFI, TLI, CFI, RMSEA, SRMR). Analysis of indicator loadings led to the removal of handgrip (.37), further improving model fit. The reduced three-component model was re-specified as a first-order model containing five indicators, and showed the best fit (NFI, CFI, SRMR). These findings suggest that a fitness construct in youth is adequately represented by three HRF components included in the theoretical definition (cardiorespiratory endurance, muscular strength, muscular endurance). These components load onto the same construct and can be tested using five tests (20m shuttle run, curl-ups, push-ups, horizontal jump, vertical jump) suitable for field-based research.

This study investigates the role of Perceived Athletic Competence (PAC) and Health-Related Fitness (HRF) in mediating the reciprocal relationship between Motor Competence (MC) and Physical Activity (PA) during the transition from primary to secondary school. MC, PA, PAC and HRF were measured in 224 participants (baseline age 12.26 ± .037 years; 51% female) in final year of primary school and one year later in first year of secondary school. Path analysis in AMOS 23 was used to test the mediating influence of PAC and HRF on the MC-PA relationship. Fit indices showed that, in both directions, HRF and PAC mediated the relationship between MC and PA (PA predicting MC; χ2 = 3.91, p = .272, CFI = .99, RMSEA = .04. MC predicting PA: χ2 = 6.46, p = .167, CFI = .99, RMSEA = .04). Pathways were stronger through HRF than through PAC, indicating that HRF is the more substantial mediator of the MC-PA relationship during the school transition. Pathways were stronger in the direction of PA predicting MC than in the reverse direction. Interventions seeking to influence PA and MC across the school transition should focus on HRF as it is a primary mediator of the MC-PA relationship.

Physical literacy (PL) is highlighted as a construct that can positively impact physical activity (PA). Measurement methods and definitions for PL exist, but vary between research groups. This variation affects the ability to compare research findings. The purpose of this study was to assess the construct validity of PL in children. PL was operationalised according to Whitehead’s (2001 ) definition, comprising confidence, motivation, physical competence, and knowledge and understanding. Participants ( n = 1073; mean age 10.86 ± 1.20 years: 53% male) were measured on: (i) confidence (Physical Activity Self-Efficacy Scale; Bartholomew et al., 2006 ), (ii) motivation (Behavioural Regulation in Exercise-Adapted; Sebire et al., 2013 ), (iii) physical competence (health-related fitness: 20 m shuttle run, back-saver sit-and-reach, handgrip strength, plank); balance (Bruininks-Oseretsky Test of Motor Proficiency 2; Bruininks, 2005 ); object-control and locomotor skills (Test of Gross Motor Development-3rd edition (TGMD-3); Ulrich, 2016 ); and (iv) knowledge and understanding (PA and sedentary guidelines). Confirmatory factor analysis (CFA) was conducted to analyse the factor structure of PL. The best-fitting model (χ² = 209.8, df = 99, p < 0.001; comparative fit index = 0.95, normed fit index = 0.91, Tucker–Lewis index = 0.93, root mean square error of approximation = 0.032, 95% confidence interval: 0.026–0.038) was a three-component model containing the domains of motivation, confidence, and physical competence. The knowledge and understanding domain did not fit the model well. Factor loadings were highest for confidence and motivation. Findings support the adoption of a pragmatic approach to PL measurement. CFA results indicated a similar factor structure as has been identified in other studies which have used different tools to measure PL domains.

Whole-school physical activity (PA) promotion programmes are recommended to increase youth PA. Evaluation of programmes is essential to ensure practice is guided by evidence. This paper evaluates the Active School Flag (ASF), a whole-school PA promotion programme in Ireland, using the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework. ASF was evaluated across three levels—(1) administration, (2) application, (3) outcomes—using a mixed-methods case study design. Existing data sources were reviewed, the programme coordinator was interviewed, and a pilot study was conducted to investigate impact on 3rd and 5th class students (3 schools, n = 126 students, age range 8–12 years). In-school Moderate to Vigorous Physical Activity (MVPA; by accelerometery), motivation for PA (BREQ), PA self-efficacy (PASES), school affect and peer social support (Kidscreen27) were measured pre-programme (0 months), post-programme (8 months), and at retention (12 months). Teacher perceptions of classroom behaviour (CBAST) were also measured pre- and post-programme. ASF has been successful in engaging 46% of primary schools nationally. Students’ in-school moderate–vigorous PA increased in all pilot-study schools from pre-programme to retention (η² = 0.68–0.84). ASF programme design facilitates implementation fidelity, adoption and maintenance through buy in from schools and government stakeholders. ASF presents as an effective PA promotion programme in the short-to-medium term for primary schools. This RE-AIM evaluation provides evidence of ASF effectiveness, alongside valuable findings that could support programme improvement, and inform future similar programmes.