Corrective Adjustment Procedures as a strategy to remove Relative Age Effects: Validation across male and female age-group long jumping.

OBJECTIVES: To validate the application of Corrective Adjustment Procedures for removing Relative Age Effects in youth athletic contexts, this study estimated the longitudinal relationships between decimal age (chronological and relative) and performance in male and female long jumpers. Using trendlines, Corrective Adjustment Procedures were applied, and Relative Age Effect distributions associated with performance attainment were re-examined. DESIGN: Retrospective longitudinal design examining competitive long-jump data between 2005 and 2019. METHODS: In Part I, participants were 689 junior Italian long jumpers (age range = 11.01-17.99 years; 56.6% females) who participated in ≥three events. Longitudinal modelling and regression equations quantified the sex-specific relationships between decimal age and long jump performance. In Part II, equations were utilised to adjust individual performance within an independent sample (N = 13,639; 50.1% females) of age-matched jumpers. Relative Age Effect distributions within attainment levels (i.e., Top 25-10%) were examined based on raw and correctively adjusted performance. RESULTS: Irrespective of sex, Relative Age Effects were prevalent across all age-groups with medium-large effect sizes at 12-17 (males and females) and 12-17 years (females) of age (Cramer's V range = 0.07-0.28). Relative Age Effect bias magnitude also increased with attainment level (i.e., Top 25-10%). Following Corrective Adjustment Procedure application, typical Relative Age Effects were removed with non-significant deviations in relative age distributions regardless of sex or age-group or attainment level (Top 25 or 10%). CONCLUSIONS: Findings provide efficacy for Corrective Adjustment Procedure application to remove Relative Age Effects across youth long jumping events. Corrective Adjustment Procedures suggest potential in improving performance evaluation, identification of technically skilled performers, and sporting experiences.

The Most Active Child Is Not Always the Fittest: Physical Activity and Fitness Are Weakly Correlated.

The present cross-sectional study aimed to evaluate the impact of physical activity level (PA) on physical fitness by controlling for individual characteristics in Italian children. A total of 329 children (girls n = 155, 42.6%; from five primary schools, 17 classes) aged 8-10 filled out the Physical Activity Questionnaire for Older Children (PAQ-C) to assess their PA level and performed anthropometric measurements (body mass, height, and BMI) and physical tests for measuring sprint (20 m sprint), cardiorespiratory fitness (shuttle-run test), balance (single-leg stance), handgrip strength (handgrip), lower-limb power (standing long-jump), peak force (countermovement jump), and low-back flexibility (sit-and-reach) skills. Linear mixed-effects models were applied to determine the relationship between physical fitness and PAQ-C score controlling for individual characteristics (i.e., gender, age, BMI). Results reported significant relationships between PAQ-C scores and sit-and-reach, shuttle-run, long-jump, and sprint tests. All considered physical tests were correlated with gender, age, and BMI, except for sit-and-reach from BMI. The variance in age, gender, BMI, and PAQ-C score accounted altogether for 30.0% of the variance in handgrip, 23.0% in single-leg stance, 26% in sit-and-reach, 36% in shuttle-run, 31% in long-jump, 34% in sprint, and 31% in countermovement jump. Therefore, the relationship between PA and fitness is not absolute and depends on the test and children's characteristics.

The Daily Mile: 15 Minutes Running Improves the Physical Fitness of Italian Primary School Children.

The Daily Mile™ is an innovative school-based intervention that requires children to run or jog outside for 15 min at a self-selected pace during class time. Today, only one study has investigated the efficacy of The Daily Mile on physical fitness, which was conducted with Scottish children. Thus, we aimed to evaluate the feasibility and effectiveness of The Daily Mile in Italian primary schools. A total of 486 children participated in The Daily Mile for 3 months (experimental group), whereas 309 children continued their daily school routine (control group). The 6-min run test, standing long jump, body mass index, and waist-to-height ratio were assessed. Their teachers completed surveys for assessing the intervention acceptability. After correction for age and gender, significant group × time interactions were observed in the 6-min run test and standing long jump results. In the post-test period, the experimental group showed improvement in the 6-min run test and standing long jump results. Overall, the teachers were satisfied with the program and found it suitable for their school context and easy to implement. The Daily Mile was successfully implemented and smoothly accepted in the day routine of Italian primary schools.

Elite national athletes reach their peak performance later than non-elite in sprints and throwing events.

OBJECTIVES: The aim of this study was to describe and analyse the performance career trajectories for Italian athletes that participated in sprint, hurdles, discus throw, and shot-put athletics events. DESIGN: Retrospective study, data collected between 1994 and 2014. METHODS: A total of 5929 athletes (female: n=2977, 50.2%) were included in the study. The age of entering competition and personal best performance was identified in the official competition records. Personal best performances were ranked in percentiles and top-level athletes were considered those in the highest 4% of the performance distribution. RESULTS: Overall, when controlling for the age of entering competition, top-level athletes reached their personal best later (i.e., around 23-25 years old) for all events compared to the rest of the athletes. Moreover, regression analysis showed that entering competitions later was linked to better performances during adulthood. Also, only 17%-26% [90% CI] of the top-level adult athletes were considered as such when they were 14-17 years old. CONCLUSIONS: Together, these findings suggest that early sport success is not a strong predictor of top-level performance at senior level. Entering sport-specific competitions later and lengthening the sports career at beyond 23-25 years of age may be important factors to reach top-level performance in sprint and throwing events.

Participation in a school-based walking intervention changes the motivation to undertake physical activity in middle-school students.

The motivation to perform physical activity is a crucial factor in achieving a persistent active lifestyle. However, motivation decreases with increasing age from childhood to adolescence. The promotion of physical activity in educational settings might be an important tool to increase motivation and, consequently, to decrease sedentary behavior. The aim of this study was to explore the effect of a 4-month school-based walking intervention on motivation to participate in physical activity among Italian middle-school students. This study included 276 students (mean age 13 ± 1 years, 41.3% female). A total of 138 students (intervention group) participated in a brief walking intervention that was added to their routine daily school activity, while a convenience sample of 138 students performed the routine daily school activity. The activity consisted of walking one kilometer outside of school buildings during the morning break. Motivation data were collected before and after the walking breaks using the Participation Motivation Questionnaire (PMQ). Controlling for age, significant interactions between group and time were observed in the "Social Status" [F(1,273) = 4.851; p = 0.028], "Team" [F(1,273) = 6.015; p = 0.015] and "Energy Release" components [F(1,273) = 8.527; p = 0.038]. Specifically, a significant decrease in the "Social Status" components of the PMQ and an increase in the "Team" and "Energy Release" components were observed in the intervention group. On the contrary. control group showed an increase in "Social Status" and a decrease in the "Team" and "Energy Release" components. Within this developmental context, incorporation of the walking activity helped to modify the motivational orientation towards physical activity to include more intrinsic factors, which were related to the possibility of remaining with classmates and peer groups and releasing a surplus of energy.

Feasibility of implementing an outdoor walking break in Italian middle schools.

Brief bouts of physical activity during the school day are an innovative method for increasing physical activity in the school setting. The purpose of the study was to investigate if the introduction of an outdoor active break, based on walking and running, in a middle school in Italy is feasible in terms of implementation (i.e., adherence, costs, safety) and acceptability (i.e., satisfaction, intent to continue use, perceived appropriateness). One hundred and forty students (aged 12 ± 1 years) and 20 teachers (aged 50 ± 8 years) participated in the activity for four months. The activity consisted of walking (or running) one kilometer outside the school buildings during the mid-morning. Data from questionnaires regarding the satisfaction with and the acceptability of the activity were collected. The activity was safely performed three to four days a week, without any costs to the school or to students' parents. Students and teachers were satisfied with the activity (positive answers from 95% and 89% of each group, respectively). Moreover, the teachers reported that the program was easy to organize and did not negatively influence their teaching activities. The intervention was easily and safely implemented, and it was considered suitable for the daily routine of an Italian middle school. Further studies are needed to examine its impact on physical activity levels and academic achievement.

Correction: Career Performance Trajectories in Track and Field Jumping Events from Youth to Senior Success: The Importance of Learning and Development.

[This corrects the article DOI: 10.1371/journal.pone.0170744.].

Career Performance Trajectories in Track and Field Jumping Events from Youth to Senior Success: The Importance of Learning and Development.

INTRODUCTION: The idea that early sport success can be detrimental for long-term sport performance is still under debate. Therefore, the aims of this study were to examine the career trajectories of Italian high and long jumpers to provide a better understanding of performance development in jumping events. METHODS: The official long-jump and high-jump rankings of the Italian Track and Field Federation were collected from the age of 12 to career termination, for both genders from the year 1994 to 2014. Top-level athletes were identified as those with a percentile of their personal best performance between 97 and 100. RESULTS: The age of entering competitions of top-level athletes was not different than the rest of the athletic population, whereas top-level athletes performed their personal best later than the rest of the athletes. Top-level athletes showed an overall higher rate of improvement in performance from the age of 13 to the age of 18 years when compared to all other individuals. Only 10-25% of the top-level adult athletes were top-level at the age of 16. Around 60% of the top-level young at the age of 16 did not maintain the same level of performance in adulthood. Female high-jump represented an exception from this trend since in this group most top-level young become top-level adult athletes. CONCLUSIONS: These findings suggest that performance before the age of 16 is not a good predictor of adult performance in long and high jump. The annual rate of improvements from 13 to 18 years should be included as a predictor of success rather than performance per se. Coaches should be careful about predicting future success based on performances obtained during youth in jumping events.