Physical fitness in childhood and adolescence: a powerful marker of health

Mediating role of physical fitness on the association between diet and health-related quality of life in adolescents

Objective

The aim of this study was to analyse whether the association between adherence to the Mediterranean diet and health-related quality of life (HRQoL) is mediated by physical fitness components (i.e., cardiorespiratory fitness, lower-limb strength, upper-limb strength and motor competence) in adolescents.

Methods

This is a cross-sectional study including mediation analyses. This study involved 181 adolescents (86 girls) aged 15.8 ± 0.3 years recruited from secondary schools and sport clubs located in Castellon (Spain). Adherence to the Mediterranean diet was evaluated using the KIDMED questionnaire. HRQoL was assessed with the KIDSCREEN-10 questionnaire. Cardiorespiratory fitness was assessed using the 20-m shuttle run test. Lower-limb strength was assessed through the standing broad jump test. Upper-limb strength was evaluated using a handgrip dynamometer. Motor competence was assessed using the 4 × 10 m shuttle run test. Mediation analyses were performed for each physical fitness component in order to assess its mediating effect on the association between adherence to the Mediterranean diet and HRQoL. Indirect effects (IE) with confidence intervals (CI) not including zero were interpreted as statistically significant.

Results

Cardiorespiratory fitness and lower-limb strength had a mediating effect on the positive association between adherence to the Mediterranean diet and HRQoL (IE = 0.11, 95 % CI = 0.01; 0.27 and IE = 0.07, 95 % CI = 0.01; 0.19). Upper-limb strength and motor competence did not act as mediators in the association between adherence to the Mediterranean diet and HRQoL (IE = 0.00, 95 % CI = -0.04; 0.07 and IE = 0.01, 95 % CI = -0.03; 0.07, respectively).

Conclusion

Our findings showed that the positive association of adherence to the Mediterranean diet on adolescents' HRQoL was mediated by physical fitness. Educational and public health strategies aiming to improve Spanish adolescents' HRQoL should focus on diet and physical fitness.

Process- and Product-Oriented Fundamental Movement Skills in Early Childhood as Predictors of Later Health-Related Fitness

INTRODUCTION

The skill domains of fundamental movement skills (FMS), emphasizing gross motor movements, including locomotor skills (LMS) and object control skills (OCS), along with process- and product-oriented measures of FMS, may predict cardiorespiratory fitness (CRF) and muscular fitness (MF) differently. This study investigates the longitudinal relationship from early childhood FMS, focusing on process-oriented LMS and OCS and product-oriented FMS, to CRF and MF in late childhood.

METHODS

The study involved 441 Finnish children (49.9% female; mean age at baseline, 5.5 yr) over a 6-yr period. FMS was evaluated using the Test of Gross Motor Development, third version, for process-oriented LMS and OCS, and the Körperkoordinationstest Für Kinder (KTK) was used to evaluate the product-oriented FMS. CRF was assessed through the total number of laps completed in the 20-m shuttle run test, whereas MF was measured via repetitions of curl-ups and push-ups. Employing a two-level cross-classified regression analysis and Cholesky decomposition, this study aimed to determine the contributions of product-oriented KTK and process-oriented LMS and OCS. Adjustments for variations in age, measurement intervals, and maturation were achieved through residualization. In addition, gender and body mass index were incorporated as covariates in the analysis.

RESULTS

The analysis revealed that process-oriented LMS (CRF: Δ R2 = 0.016; MF: Δ R2 = 0.014) significantly predicted later health-related fitness, whereas OCS did not. However, KTK exhibited a better ability to predict both CRF (Δ R2 = 0.092) and MF (Δ R2 = 0.032), overshadowing process-oriented measures.

CONCLUSIONS

In conclusion, the findings suggest that KTK, which potentially encompasses a broader spectrum of fitness elements along with FMS, more effectively predicts health-related fitness components than process-oriented FMS.

No Impact of Anthropometric and Fitness Factors on Speed-Agility in Young Soccer Players: Is It a Cognitive Influence?

PURPOSE

Agility in young soccer players has long been associated with physical attributes like strength, speed, and power. The aims of this study were to investigate the relationship between cognitive factors and agility performance in this unique population.

METHODS

39 young soccer players age 13.56 (SD 0.58) years were assessed for leg-muscle function (jump tests) and maturation status (peak height velocity). The Y-Agility Test, which included decision making in players, was used to measure performance. Cognitive factors such as perceptual skills and decision making were evaluated with the Y-Agility Test.

RESULTS

The linear regression showed an absence of significance between the Y-Agility Test and drop-jump contact (P = .283), Y-Agility Test and drop-jump flight (P = .185), Y-Agility Test and squat jump (P = .868), and Y-Agility Test and countermovement jump (P = .310). The linear mixed-model analyses suggested a difference between early-average maturers (P = .009) and early-late maturers (P = .005) but did not show a difference between average-late subjects (P = 1.000). Drop-jump flight did not show a difference in maturation (early-average P = 1.000; early-late P = 1.000; average P = 1.000). Squat-jump performance did not demonstrate any significance (early-average P = .618; early-late P = 1.000; P = 1.000). Countermovement-jump performance did not show any significance (early-average P = 1.000; early-late P = 1.000; average-late P = .492). Finally, agility performance does not show any significance between maturation levels (early-average maturer P = .450; early-late P = 1.000; average-late P = .830).

CONCLUSION

Agility in young soccer players appears to follow a nonlinear trajectory, with cognitive factors possibly playing a more significant role than previously thought.

Identifying profiles of actual and perceived motor competence measured with aligned instruments: Differences in (enjoyment of) physical fitness

A person-centred approach was used to examine whether children with various actual and perceived motor competence (AMC and PMC) profiles differ in (enjoyment of) physical fitness (PF). The strength of the relationship between AMC and PMC was also assessed through aligned assessment tools. A sample of 287 7-11-year-old children (47.40% boys, Mage = 8.92 ± .78 years) was assessed on AMC with the KörperkoordinationsTest für Kinder (KTK3), and on PF with six validated fitness tests. Animated videos fully aligned with the AMC- and PF-tests were used to assess children's PMC and enjoyment of PF, respectively. Cluster analyses identified one convergent (i.e. high AMC-high PMC) and three partially convergent AMC-PMC profiles (i.e. low AMC-high PMC). Furthermore, children with relatively high AMC (i.e. high-average profile) reported higher PF (F = 30.99, p < .001), while children with relatively high PMC (i.e. average-high profile) reported higher enjoyment of PF (F = 9.02, p < .001). The correlation between AMC and PMC was significant but weak (r = .16). Overall, it seems important to invest in both children's AMC and PMC as they may support a higher (enjoyment of) PF, potentially leading to higher PA-levels.

Teamwork Competencies and Their Influence on Health Literacy and Other Health Variables

The ability to work in a team is a skill of special relevance for multiple facets of life, increasing performance and optimizing the process in any task. This work aimed to study whether teamwork skills were related to different health variables. The sample consisted of 671 military personnel from the Spanish Army. The instrument is composed of the Health Literacy Questionnaire-the Teamwork Skills Questionnaire, and Rosenberg's self-esteem scale. The study concludes that the level of teamwork skills of the military is high, as well as their level of health literacy and their self-perception of health. However, their self-esteem is medium. Teamwork competencies are positively associated with a higher level of health literacy, with a high self-perception of their health, with the level of physical activity and negatively with self-esteem and the number of hospital admissions.

Exploring cardiovascular health in children: the influence of Hemoglobin-to-Platelet ratio in contrasting rural and urban communities

Understanding the associations and possible mechanisms between Cardiorespiratory Fitness (CRF) and residential location is an important focus of public health research. This is a cross-sectional study carried out with 2250 students (6-17 years), from southern Brazil. In addition to age, sex, and body size measurements, we also recorded hemoglobin and platelet count measurements using venous blood samples (10 ml). The CRF was measured using the 6-minute run/walk test, with predictors explored via allometry. Results identified a novel and independent association between the hemoglobin-to-platelet count ratio and children's CRF, after controlling for confounders. We also provide evidence of a possible mechanism for this association, having identified reduced measures of hemoglobin and increased platelet counts observed in children living in urban (vs rural) areas. These results suggest the need for more effective public health practices and policies addressing the built enviroment´s health effects in Brazil and potentially other congested ciries.

Physical Activity, Body Composition, and Fitness Variables in Adolescents After Periods of Mandatory, Promoted or Nonmandatory, Nonpromoted Use of Step Tracker Mobile Apps: Randomized Controlled Trial

BACKGROUND

It is not known whether an intervention made mandatory as a physical education (PE) class assignment and aimed at promoting physical activity (PA) in adolescents can create a healthy walking habit, which would allow further improvements to be achieved after the mandatory and promoted intervention has been completed.

OBJECTIVE

The aims of this study were to (1) investigate whether, after a period of using a step tracker mobile app made mandatory and promoted as a PE class assignment, adolescents continue to use it when its use is no longer mandatory and promoted; (2) determine whether there are changes in the PA level, body composition, and fitness of adolescents when the use of the app is mandatory and promoted and when it is neither mandatory nor promoted; and (3) analyze whether the covariates maturity status, gender, and specific app used can have an influence.

METHODS

A total of 357 students in compulsory secondary education (age: mean 13.92, SD 1.91 y) participated in the study. A randomized controlled trial was conducted consisting of 2 consecutive 10-week interventions. Participants' PA level, body composition, and fitness were measured at baseline (T1), after 10 weeks of mandatory and promoted app use (T2), and after 10 weeks of nonmandatory and nonpromoted app use (T3). Each participant in the experimental group (EG) used 1 of 4 selected step tracker mobile apps after school hours.

RESULTS

The results showed that when the use of the apps was neither mandatory nor promoted as a PE class assignment, only a few adolescents (18/216, 8.3%) continued the walking practice. After the mandatory and promoted intervention period (T1 vs T2), a decrease in the sum of 3 skinfolds (mean difference [MD] 1.679; P=.02) as well as improvements in the PA level (MD -0.170; P<.001), maximal oxygen uptake (MD -1.006; P<.001), countermovement jump test (MD -1.337; P=.04), curl-up test (MD -3.791; P<.001), and push-up test (MD -1.920; P<.001) in the EG were recorded. However, the changes between T1 and T2 were significantly greater in the EG than in the control group only in the PA level and curl-up test. Thus, when comparing the measurements taken between T1 and T3, no significant changes in body composition (P=.07) or fitness (P=.84) were observed between the EG and the control group. The covariates maturity status, gender, and specific app used showed a significant effect in most of the analyses performed.

CONCLUSIONS

A period of mandatory and promoted use of step tracker mobile apps benefited the variables of body composition and fitness in adolescents but did not create a healthy walking habit in this population; therefore, when the use of these apps ceased to be mandatory and promoted, the effects obtained disappeared.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06164041; https://clinicaltrials.gov/study/NCT06164041.

Secular Contrasts in Physical Fitness and Athletic Skills in Japanese Elementary School Students (11-Year-Olds)

Since 1964, Japan has been conducting a wide fitness and athletic skills evaluation among 2000-3000 school children. This study used data made public by the Japan Sports Agency from four events that have continuously been evaluated from 1964 to 2021-grip strength, 50 meter dash, repetitive side jumps, and softball throw-to depict a secular trend over the course of 58 years. This is to statistically categorize these into generations, establishing secular contrast by identifying high and low scores for each event within the categorized generations, with the intent to examine the factors embedded within the background. The generations that had the highest average across all four events were the measurements made in 1970-1993 for males and in 1972-1994 for females. Changes made to the curriculum guidelines may have played a role in the differences found within each event. The goal of physical education and its syllabus and assigned hours in the curriculum guidelines are revised approximately every 10 years to meet social demand. Changes in the social and living environments surrounding children may be exhibited in the form of secular contrast in the measured physical fitness and athletic skills.

Impact of the ActTeens Program on physical activity and fitness in adolescents: a cluster randomized controlled trial

BACKGROUND

The aim of our study was to evaluate the impact of the ActTeens Program on physical activity and health-related physical fitness among adolescents in Brazil.

METHODS

The "ActTeens Program" was conducted using a cluster-randomized controlled trial during 24-week school term. The sample consisted of 317 adolescents (52.7% girls; 13.61 ± 0.70 years) from four secondary schools that were randomly assigned to intervention group (N = 169) or control group (N = 148). This school-based physical activity (PA) intervention involved two components: (i) structured physical activity sessions delivered within physical education (PE) and (ii) healthy lifestyle guidance (mHealth). The primary outcome was PA assessed using Physical Activity Questionnaire for Adolescents (PAQ-A); secondary outcomes included muscular (MF) and cardiorespiratory fitness (CRF) assessed using 90-push-up, handgrip dynamometer, standing long jump, and 20 m PACER shuttle run test. Assessments were conducted at baseline, 12- and 24-week. Intervention effects were assessed using linear mixed models (LMM).

RESULTS

For the primary outcome (PA), no significant group-by-time effects were observed for physical education based-PA (0.3 score; 95%CI: -0.1; 0.6; and - 0.01 score; 95%CI: -0.03; 0.03, at 12-wk and 24-wk respectively) and total PA (-0.02 score; 95%CI: -0.2; 0.2; and - 0.01score; 95%CI: -0.2; 0.2, at 12 and 24 weeks respectively). After 24 weeks, we observed a significant group by time effects for lower body muscular fitness (12.9 cm; 95%CI, 3.2 to 22.2).

CONCLUSION

The implementation of aerobic and muscle-strengthening exercises used in the ActTeens intervention did not lead to improvements in physical activity. The intervention resulted in improved lower body muscular fitness, however, we found no significant differences for upper body muscular and cardiorespiratory fitness.

The Effects of a School-Based Physical Activity Program on Physical Fitness in Egyptian Children: A Pilot Study from the DELICIOUS Project

BACKGROUND

Ensuring the physical fitness of Egyptian children is of paramount importance to their overall well-being, given the unique socio-cultural and educational barriers they face that may hinder their active participation. As part of the DELICIOUS project, the "Be Fit Program" aims to increase the level of physical fitness among Egyptian school-aged children. This study explores the effectiveness of a structured, six-week physical activity (PA) program in improving various facets of physical fitness in children, including body composition, speed, coordination, muscular strength, and cardiovascular endurance. With the increasing prevalence of sedentary lifestyles, such efforts are imperative to improve overall health outcomes.

METHODS

A cohort of 125 children, aged 8.50 to 12.25 y (mean age 10.19 ± 1.03 y), participated in the study. Their body composition, speed, coordination, strength, and aerobic fitness were assessed before and after the Be Fit Program using the revised International Physical Performance Test Profile. Paired t-tests were used to detect changes between the pre- and post-tests.

RESULTS

Following the six-week intervention, statistical analyses revealed significant improvements in coordination and lower body strength (p < 0.01). Aerobic endurance showed marginal improvements, approaching statistical significance (p = 0.06). Conversely, there were no statistically significant changes in body composition, speed, or upper body strength (p > 0.05).

CONCLUSIONS

The study confirms that tailored, non-competitive physical activities can positively influence specific fitness components in Egyptian children. However, achieving holistic improvements across all targeted fitness domains may require further strategic adjustments or a longer program duration. This pilot study underscores the importance of culturally tailored, school-based PA programs and highlights the continued need for research and program refinement to comprehensively improve children's fitness in the Egyptian context.

Exercise prescription for the prevention and treatment of chronic diseases in primary care: Protocol of the RedExAP study

BACKGROUND

Existing evidence supports the effectiveness of exercise in preventing and treating chronic diseases, yet its integration into clinical practice remains limited. This study protocol aims to address the evidence-practice gap by exploring barriers to exercise prescription in primary care and developing a clinical practice guideline (CPG).

METHODS

Employing a qualitative approach, focus groups will be conducted to investigate primary care professionals' challenges in prescribing exercise and patients' adherence to recommendations. Phenomenological analysis will facilitate data interpretation. Data triangulation, expert analysis, and quality criteria will ensure study reliability. The CPG development process is outlined, emphasizing transdisciplinary collaboration and patient involvement.

CONCLUSION

The RedExAP study responds to the imperative for evidence-based exercise integration in primary care. The study's combined qualitative exploration and CPG development present the potential to improve health outcomes and cost-effectiveness. By elucidating primary care professionals' and patients' perspectives, the study contributes to enhancing exercise prescription adoption. The innovative transdisciplinary approach aligns with the 2030 Agenda, promoting better population health and greater social well-being, showing promise in alleviating chronic disease burdens. This study's findings lay the groundwork for advancing evidence-based exercise interventions within primary care to transform chronic disease management.

Effects of a staff-led multicomponent physical activity intervention on preschooler's fundamental motor skills and physical fitness: The ACTNOW cluster-randomized controlled trial

BACKGROUND

Fundamental motor skills (FMS) and physical fitness (FIT) play important roles in child development and provide a foundation for lifelong participation in physical activity (PA). Unfortunately, many children have suboptimal levels of PA, FMS, and FIT. The Active Learning Norwegian Preschool(er)s (ACTNOW) study investigated the effects of a staff-led PA intervention on FMS, FIT, and PA in 3-5-year-old children.

METHODS

Preschools in Western Norway having ≥ six 3-4-year-old children were invited (n = 56). Of these, 46 agreed to participate and were cluster-randomized into an intervention (n = 23 preschools [381 children, 3.8 yrs., 55% boys]) or a control group (n = 23 [438, 3.7 yrs., 52% boys]). Intervention preschools participated in an 18-month PA intervention involving a 7-month staff professional development between 2019 and 2022, amounting to 50 h, including face-to-face seminars, webinars, and digital lectures. Primary outcomes in ACTNOW were cognition variables, whereas this study investigated effects on secondary outcomes. FMS was measured through 9 items covering locomotor, object control, and balance skills. FIT was assessed as motor fitness (4 × 10 shuttle-run test) and upper and lower muscular strength (handgrip and standing long jump). PA was measured with accelerometers (ActiGraph GT3X +). All measures took place at baseline, 7-, and 18-month follow-up. Effects were analysed using a repeated measures linear mixed model with child and preschool as random effects and with adjustment for baseline scores.

RESULTS

Participants in the intervention preschools showed positive, significant effects for object control skills at 7 months (standardized effect size (ES) = 0.17) and locomotor skills at 18 months (ES = 0.21) relative to controls. A negative effect was found for handgrip strength (ES = -0.16) at 7 months. No effects were found for balance skills, standing long jump, or motor fitness. During preschool hours, sedentary time decreased (ES = -0.18), and light (ES = 0.14) and moderate-to-vigorous PA (ES = 0.16) increased at 7 months, whereas light PA decreased at 18 months (ES = -0.15), for intervention vs control. No effects were found for other intensities or full day PA.

CONCLUSIONS

The ACTNOW intervention improved some FMS outcomes and increased PA short-term. Further research is needed to investigate how to improve effectiveness of staff-led PA interventions and achieve sustainable improvements in children's PA, FMS, and FIT.

TRIAL REGISTRATION

Clinicaltrials.gov, identifier NCT04048967 , registered August 7, 2019.

FUNDING

ACTNOW was supported by the Research Council of Norway (grant number 287903), the County Governor of Sogn og Fjordane, the Sparebanken Sogn og Fjordane Foundation, and the Western Norway University of Applied Sciences.

Study on the relationship and related factors between physical fitness and health behavior of preschool children in southwest China

OBJECTIVE

To investigate the physical fitness level and health behavior status of preschool children in China, explore the relationship between physical fitness and health behavior, and further reveal the main factors affecting health behavior, to provide a reference for improving the physical fitness level of preschool children and maintaining healthy behavior.

METHODS

A total of 755 preschool children (394 boys and 361 girls, aged 4.52 ± 1.11 years) were selected from Chongqing and Liupanshui in China by cluster random sampling method for questionnaire survey and physical monitoring, and SPSS21.0 software was used to process and analyze the data.

RESULTS

(1) Heart rate (p = 0.015), protein content (p < 0.001), and time spent on the balance beam (p < 0.001) were significantly lower in boys than in girls, while BMI (p = 0.012), muscle mass (p < 0.001), and distance of standing long jump (p < 0.001) were significantly higher in boys than in girls. Meanwhile, systolic blood pressure (p = 0.004) and diastolic blood pressure (p = 0.001) of rural children were significantly higher than those of urban children, while BMI (p < 0.001) and sitting forward flexion (p = 0.019) were significantly lower than those of urban children. (2) The light-intensity physical activity (LPA) and moderate to vigorous physical activity (MVPA) of boys were significantly higher than that of girls (p < 0.001), and the MVPA of urban children was significantly higher than that of rural children (p = 0.001), and the former participated in sports classes more frequently (p < 0.001). (3) There was a significant correlation between physical activity (PA) and physical fitness indicators of preschoolers. Participating in sports interest classes was only significantly correlated with systolic blood pressure (r = 0.08) and sitting forward flexion (r = 0.09). (4) The PA level of preschool children was related to gender, household registration, kindergarten nature, age, residence environment, parental support, and participation degree. Participation in sports interest classes was related to gender, the nature of the kindergarten, household registration, age, and parent participation. Daily screen time was related to household registration, the nature of the kindergarten, the environment of residence, and the value perception of parents.

CONCLUSIONS

There were different degrees of correlation between preschool children's physical fitness and health behaviors, and children's health behaviors were closely related to gender, environment, parents, and other factors. Therefore, how to increase the protective factors of children's health behaviors and controlling the risk factors may be crucial to promoting the development of good health behaviors and improving the physical fitness of preschool children.

Lifestyle as a Modulator of the Effects on Fitness of an Integrated Neuromuscular Training in Primary Education

The objective was to evaluate changes in fitness after an integrated neuromuscular training (INT) intervention in primary school children and to evaluate how lifestyle behaviors and parental education modulate these changes. One hundred and seventy children (7.45 ± 0.34 years; 52% girls) were included. Cardiorespiratory fitness (half-mile run test), a 10 × 5 m shuttle run test, standing broad jump (SBJ), handgrip dynamometer, body mass index (BMI) and fat mass percentage (FM%) were assessed before and after the 3-month intervention (20 min of INT in the physical education class, twice per week). The Mediterranean diet (MD), sleep time and parental education level (PEL) were evaluated by questionnaires, and adherence to physical activity (PA) recommendations was measured with a triaxial accelerometer before the intervention. After the intervention, there were improvements in the 10 × 5 test and the SBJ. Only girls had improvements in the handgrip test, BMI SDS and FM%. After correcting for confounding variables, only BMI was significantly improved whereas strength improved in the participants non-compliant with the PA recommendations or pertaining to families of high PEL. The INT produced improvements in fitness in a brief period and in different subgroups of pupils (inactive and with diverse sociocultural environments).

Individual and school correlates of body mass index and cardiorespiratory fitness in primary school children from the REACT project: A multivariate multilevel analysis

OBJECTIVE

This paper examines the relationship between body mass index (BMI) and cardiorespiratory fitness (CRF) using a multivariate multilevel approach and investigates the links between individual and school-related correlates with children's BMI and CRF.

METHODS

This cross-sectional sample included 1014 children (6-10 years) from 25 Portuguese primary schools. BMI was calculated, and CRF was assessed with the PACER test. Fundamental movement skills (FMS) included five object control tasks. Moderate-to-vigorous physical activity (MVPA), sleep, and sedentary time were assessed with the ActiGraph wGT3X-BT accelerometer. Socioeconomic status (SES) and school variables were also obtained. A multivariate multilevel model was used, and alpha was set at 5%.

RESULTS

BMI and CRF systematically increased with age. Most of the joint variance (94.4%) was explained at the child level, and BMI and CRF were correlated at this level (ρ = -.37). More active children demonstrated higher CRF levels and had lower BMI levels; sedentary and sleep time were not significantly associated with BMI or CRF. FMS were positively associated with CRF but were not significantly associated with BMI. Children at higher SES were more fit and had lower BMI than their peers of lower SES. Finally, school-level variables were not significantly related to BMI and CRF.

CONCLUSION

BMI and CRF had a low but statistically significant negative correlation in this sample of children. Most of the variation in BMI and CRF was explained by child-level characteristics.

Junior parkrun pilot in Australia: A real world evaluation

ISSUE ADDRESSED

Regular physical activity is important for children's health. Parkrun supports communities to deliver free, weekly, 5 km events in 22 countries around the world and is the largest physical activity model delivered at scale in the world. Junior parkrun aims to encourage children aged 4-14 years to be active outdoors through providing safe, cost-free and non-competitive weekly timed walk, run or jog over a 2-km distance. The aim of this study is to evaluate the junior parkrun pilot in Australia.

METHODS

A process evaluation was conducted using routinely collected data of junior parkrun participants, as well as a self-completed questionnaire.

RESULTS

A total of 1827 children had registered and participated in at least one junior parkrun over the course of the pilot period. Participants had, on average, attended 10% of the junior parkrun events including and subsequent to their first participation by the end of the study period. Majority of parents (61%) said that junior parkrun had increased their child's physical activity either a little or a lot, and most agreed or strongly agreed that junior parkrun was fun (90%), enjoyable (91%), energising (85%) and challenging (70%).

CONCLUSION

The junior parkrun pilot appears to show promise in Australia for enabling children to engage in physical activity, in their local communities in a fun and inclusive way.

SO WHAT

Parkrun junior can co-exist with other organised sports programs; however, it can also specifically target those not participating in any sports, given the high levels of enjoyment in a non-competitive, non-team environment.

Cardiorespiratory fitness and muscular fitness correlates in youth: A hierarchy of behavioral, contextual, and health-related outcomes

OBJECTIVES

Despite the health importance of identifying correlates of physical fitness in youth, no investigation to date has explored the influence of behavioral, health-related, and contextual correlates simultaneously. We investigated the hierarchical relationship of multiple modifiable correlates favoring or diminishing cardiorespiratory and muscular fitness in youth.

DESIGN

Cross-sectional investigation.

METHODS

In a sample of 5174 children and adolescents, 31 correlates were hierarchized according to their impact on cardiorespiratory and muscular fitness assessed using the FITESCOLA® fitness battery. A Chi-squared Automatic Interaction Detection approach was employed and measures of correlation and association were used to investigate the relationship between physical fitness and correlates.

RESULTS

In children, body mass index was the most relevant factor to discriminate between high and low cardiorespiratory and muscular fitness of the upper, middle, and lower body. While body mass index was more important than any other correlate to differentiate levels of upper and lower body muscular fitness during adolescence, specific characteristics of sports participation emerged as key factors to discriminate between high and low cardiorespiratory fitness and middle body muscular fitness. Other correlates, including the self-report of active recess time, active commuting to school, favorable neighborhood conditions, and limited time on screens and cellphones, were demonstrative of favorable physical fitness levels.

CONCLUSIONS

Both body composition and sports-related characteristics emerged as the two most relevant factors of physical fitness in youth. Additional health benefits may be obtained from building supportive environments for sports and healthy exercise habits within the household and at different school education levels.

Physical Fitness Surveillance and Monitoring Systems Inventory for Children and Adolescents: A Scoping Review with a Global Perspective

Surveillance of health-related physical fitness can improve decision-making and intervention strategies promoting health for children and adolescents. However, no study has comprehensively analyzed surveillance/monitoring systems for physical fitness globally. This review sought to address this gap by identifying: (1) national-level surveillance/monitoring systems for physical fitness among children and adolescents globally, (2) the main barriers and challenges to implementing surveillance/monitoring systems, and (3) governmental actions related to existing surveillance/monitoring systems. We used a scoping review to search, obtain, group, summarize, and analyze available evidence. Our review involved three stages: (1) identification of surveillance systems through a systematic literature review, with complementary search of the grey literature (e.g., reference lists, Google Scholar, webpages, recommendations), (2) systematic consultation with relevant experts using a Delphi method to confirm/add systems and to gather and analyze information on the barriers and challenges to implementing systems, and (3) Web searches for public documents on government sites and surveillance/monitoring system pages, and direct internet searches to identify relevant governmental actions related to surveillance systems. A total of 15 fitness surveillance/monitoring systems met our inclusion criteria. Experts identified a lack of government support and funding, and the low priority of fitness on the public health agenda as the main barriers/challenges to implementation. Several governmental actions related to surveillance systems were identified, including policies, strategies, programs, and guidelines. We propose a Global Observatory of Physical Fitness to help address these issues.

Region of Murcia's 2022 report card on physical activity for children and youth

Objective

The aim of this review was to summarize the process and results of the Region of Murcia's 2022 Report Card on Physical Activity for Children and Youth.

Methods

Indicators from the Global Matrix initiative (Overall Physical Activity, Organized Sport & Physical Activity, Physical Fitness, Active Play, Active Transport, Sedentary Behaviors, Family & Peers, School, Community & Environment, and Government) were evaluated based on the best available data in the Region of Murcia.

Results

Active play was the indicator with the highest grade (B+), followed by Organized Sport & Physical Activity (B) and Active Play (B). School and Family and Peers indicators obtained a C+ and C grade, respectively. Both Community and Environment and Sedentary Behaviors indicators received a D+ grade. The grade for Overall Physical Activity and Government indicators was D. Physical Fitness was the indicator with the lowest grade of this Report Card (D-). None of the indicators received an incomplete grade (INC) because of a lack of available information.

Conclusions

The present Report Card offers evidence highlighting the low level of physical activity in Spanish children and adolescents living in the Region of Murcia. Further studies and surveillance efforts are urgently needed for most of the indicators analyzed, which should be addressed by researchers and the Region of Murcia's Government for this specific population. A strong commitment from the Government of the Region of Murcia is needed at all levels to promote a cultural change that will lead children and young people in this region to improve the current situation.

Breastfeeding, Walking Onset, and Abdominal Obesity Are Determinants of Physical Fitness among Latin American and Spanish Schoolchildren: A Cross-Cultural Study

OBJECTIVE

To comp+are levels of physical fitness between Ecuador and Spain and identify whether breastfeeding period, walking onset, and abdominal obesity are determinants of physical performance in schoolchildren from Ecuador and Spain.

METHODS

a total of 352 schoolchildren (6-12 years old) from Ecuador (n = 176) and Spain (n = 176) joined in this study. Anthropometric measures, socio-demographic characteristics, and physical fitness were evaluated.

RESULTS

Spanish schoolchildren showed better performance in handgrip strength, standing long jump, and 25 m sprint (p = 0.021; p < 0.001; p < 0.001; p < 0.001, respectively). Furthermore, Spanish children showed better cardiorespiratory fitness (p < 0.001) and a higher VO2 max (p = 0.002) with regards to their peers. In addition, children from Ecuador and Spain showed an influence of breastfeeding period (p ranged from <0.001 to 0.043) and walking onset (p ranged from <0.001 to 0.032) on physical performance. Moreover, physical fitness components were protective factors of abdominal obesity in Ecuadorian and Spanish schoolchildren (p ranged from =0.001 to 0.049).

CONCLUSIONS

Our findings revealed the influence of the infancy period and the onset of walking on children's physical performance, highlighting the importance of these factors in motor development during early childhood and also their influence in middle childhood and throughout adulthood.

Cardiovascular and cardiorespiratory effects of high-intensity interval training in body fat responders and non-responders

This study aimed to investigate cardiovascular and cardiorespiratory adaptations to exercise intervention among participants who showed higher (responders-RSBFP) and lower (non-responders-NRSBFP) levels of body fat percentage (BFP) responsiveness. Adolescents (42.5% males) participated in a ten-week school-based high-intensity interval training (HIIT), followed by a comparison of BFP, blood pressure (BP), and cardiorespiratory fitness (CRF). RSBFP age of 16.15 ± 0.36 years, body height 170.82 ± 8.16 cm, weight 61.23 ± 12.80 kg, and BMI 20.86 ± 3.29 kg/m2. Meanwhile, NRSBFP age of 16.04 ± 0.36 years, body height 168.17 ± 8.64 cm, weight 57.94 ± 8.62 kg, and BMI 20.47 ± 2.24 kg/m2. HIIT intervention impacted BFP, with a higher decrease in the RSBFP than the NRSBFP (ΔBFPRs = - 2.30 ± 3.51(10.34%) vs. ΔBFPNRs = 1.51 ± 1.54(6.96%) p < 0.001). The primary comparison showed a statistically significant interaction effect in relation to CRF (F(1,71) = 14.12; p < 0.001). Detailed comparisons showed large and significant CRF changes in RSBFP (7.52%; d = 0.86; p < 0.001) but not in NRSBFP (2.01%; d = 0.11; p = 0.576). In addition, RSBFP and NRSBFP benefited equally in SBP (5.49%, d = 0.75; p < 0.001; 4.95%, d = 0.74; p < 0.001, respectively). These findings highlight that exercise benefits on body fat may be mainly related to gains in CRF. Due to substantial intra-individual variability in adaptation, there is a need for personalized intervention tailored for those with different reaction thresholds in body mass components.

Exercise blood pressure, cardiorespiratory fitness, fatness and cardiovascular risk in children and adolescents

Cardiovascular disease remains the leading cause of mortality on a global scale. Individuals who possess risk factors for cardiovascular disease, such as high blood pressure (BP) and obesity, face an elevated risk of experiencing organ-specific pathophysiological changes. This damage includes pathophysiological changes in the heart and peripheral vascular systems, such as ventricular hypertrophy, arterial stiffening, and vascular narrowing and stenosis. Consequently, these damages are associated with an increased risk of developing severe cardiovascular outcomes including stroke, myocardial infarction, heart failure, and coronary heart disease. Among all the risk factors associated with cardiovascular disease, high blood pressure emerges as the most prominent. However, conventional resting BP measurement methods such as auscultatory or oscillometric methods may fail to identify many individuals with asymptomatic high BP. Recently, exercise BP has emerged as a valuable diagnostic tool for identifying real (high) blood pressure levels and assessing underlying cardiovascular risk, in addition to resting BP measurements in adults. Furthermore, numerous established factors, such as low cardiorespiratory fitness and high body fatness, have been confirmed to contribute to exercise BP and the associated cardiovascular risk. Modifying these factors may help reduce high exercise BP and, consequently, alleviate the burden of cardiovascular disease. A significant body of evidence has demonstrated cardiovascular disease in later life have their origins in early life. Children and adolescents with these cardiovascular risk factors also possess a greater propensity to develop cardiovascular diseases later in life. Nevertheless, the majority of previous studies on the clinical utility of exercise BP have been conducted in middle-to-older aged populations, often with pre-existing clinical conditions. Therefore, there is a need to investigate further of the factors influencing exercise BP in adolescence and its association with cardiovascular risk in early life. Our previously published work showed that exercise BP is a potential useful method to detect adolescents with increased cardiovascular risk. Children and adolescents with cardiovascular risk factors are more likely to develop cardiovascular diseases later in life. However, previous studies on the clinical utility of exercise BP have largely focused on middle-to-older aged populations with pre-existing clinical conditions. Therefore, there is a need to investigate further the factors influencing exercise BP in adolescence and its association with future cardiovascular risk. Our previous studies, which focused on exercise BP measured at submaximal intensity, have shown that exercise BP is a potentially useful method for identifying adolescents at increased cardiovascular risk. Our previous findings suggest that improving cardio-respiratory fitness and reducing body fatness may help to reduce the risk of developing cardiovascular disease and improve overall cardiovascular health. These findings have important implications for the development of effective prevention and early detection strategies, which can contribute to improved public health outcomes.

A Novel Summer Camp Integrating Physical, Psychological, and Educational Health in Youth: The THINK Program

Numerous youth summer programs focus upon physical fitness, nutritional health, psychological well-being, or education. Few, however, have integrated all of these elements into a single program. The Translational Health in Nutrition and Kinesiology (THINK) program provides an integrative nutrition and exercise science curriculum that is interfaced with social emotional learning (SEL) and STEM education to enhance healthy behaviors in youth. The purpose of this study was to determine whether the THINK program could improve physical fitness, nutrition habits, SEL, and STEM education in a 6-week summer program covering a 3-year period. Participants from South Miami were enrolled in THINK (n = 108, 58 males, 50 females, 12.03 + 0.56 years). Physical fitness assessments, the Positive Youth Development Inventory (PYDI), the Students' Attitude Towards STEM Survey, and the Adolescent Food Habits Checklist (ADFH) were recorded at baseline and post-testing. Means and standard error values were evaluated for all dependent variables. Paired samples t-tests (SPSS version 27) were used to determine changes. Improvements in cardiorespiratory fitness (p < 0.001), power (p < 0.006), flexibility (p < 0.001), agility (p < 0.001), muscular endurance (p < 0.001), lean body mass (p < 0.001), ADFH (p < 0.001), and PYDI (p = 0.038) were found. An integrative summer fitness program can result in improvements in physical fitness, nutrition habits, and SEL in as little as six weeks.

The Influence of Kindergarten Environment on the Development of Preschool Children's Physical Fitness

The aim of this research is to find out to what extent the special qualifications of physical education teachers and the physical environment of kindergartens influence the physical development of preschoolers. Forty-four kindergartens across Estonia participated in the study, half of which had a physical education teacher (PEt), whereas the remaining 22 kindergartens were taught by non-qualified kindergarten teachers (NoPEt). Six Eurofit fitness tests were used to assess the physical development of children (n = 704; aged 6-7 years old, with an average age of 6.55 ± 0.5 years). An analysis of variance was used to compare the mean values of the fitness test results of the two groups. Linear regression analysis was applied to clarify the influence of individual and environmental factors on children's fitness scores. In kindergartens where the position of a PEt had been created, the results of children's physical fitness were statistically significantly better, more specifically in handgrip strength (m = 12.0, 95% CI = 11.8-12.3 vs. m = 11.5, 95% CI = 11.2-11.7) and in speed tests (m = 23.0, 95% CI = 22.8-23.2 vs. m = 23.6, 95% CI = 23.3-23.8). According to the teacher interviews, these kindergartens also had more rooms and areas specially created for physical exercises. The study revealed that the physical development of children is, when controlling for other individual and environmental factors, influenced by the professional qualification of the PE teacher (95% CI = 0.06-0.56) as well as children's participation in sports training (95% CI = 0.29-0.83). These findings are important for preschool institutions and municipalities in designing the optimal physical environment for facilitating children's physical fitness.

Changes in Muscle Mass and Strength in Adolescents Following High-Intensity Functional Training with Bodyweight Resistance Exercises in Physical Education Lessons

(1) Background: The growing prevalence of obesity, diabetes, hypertension, and declining physical fitness among children and adolescents due to sedentary lifestyles has increased attention toward preventive intervention to tackle this issue. This study investigated the age-related effects of high-intensity functional training (HIFT), based on bodyweight resistance exercises conducted during physical education lessons, on muscle mass and strength improvement. (2) Methods: Adolescent males (n = 116) were allocated to four HIFT experimental groups (EGs) and four standard physical education program control groups (CGs) according to age (15, 16, 17, and 18 years [y]). The changes in muscle mass (absolute and relative to height [SMI]), hand-grip strength (HGS), sit-ups (SUs), and standing broad jump (SBJ) were analyzed using two-way analysis of variance (ANOVA) with Bonferroni tests. (3) Results: HIFT significantly increased muscle mass and scores in all strength tests (p < 0.01), while chronological age was significant for HGS (p < 0.01). Interactions between HIFT and chronological age categories were observed for HGS (p = 0.01) and SBJ (p < 0.03). Detailed post hoc tests revealed improvement in muscle mass across all chronological age categories for both approaches (p < 0.05). The 18y-EG group improved HGS over their control peers (p < 0.01), the EG groups significantly improved their SU results (p < 0.01), and SBJ improved in the 15y-EG and 18y-EG groups compared to their control (p < 0.01). (4) Conclusions: This research highlights the effectiveness of a school-based HIFT program in promoting muscle mass gains and enhancing muscle strength among adolescents. The findings offer valuable insights for implementing bodyweight exercises during physical education classes.

The Role of Sports Club Participation on Stability of Motor Performance and Body Composition: A Longitudinal Study in Primary School Children

Methods

MP and BC of 295 children (161 girls) with a mean age of 8.42 ± 0.36 years were measured annually with the German Motor Test 6-18. Based on self-reports, children were divided into three groups according to consistent (CON), partial (PAR), and nonparticipation (NO) in SC. NO and PAR were then combined into NO-PAR. The stability of MP and BC was determined using Pearson's correlation coefficient (r). Associations of SC participation, MP, and BC were examined using robust mixed-model ANOVA (mmANOVA) additionally with first grade as covariate (ANCOVA).

Results

More girls (39%) than boys (25%) were classified in PAR. The stability of MP (r = .755) and BMI (r = .889) was moderately high. Children in CON (r = .847) showed lower stability in BMI than NO-PAR (r = .923). mmANOVA revealed better overall MP for both sexes in CON except for balance and BMI. Boys in CON showed better performance in flexibility, endurance, and speed than NO-PAR. ANCOVA confirmed unadjusted results for boys.

Conclusion

Lower stability of BMI due to CON indicates a greater variance in ranking and thus the chance to adjust weight management in childhood. Girls' MP benefited less from SC participation, which may be due to their more frequent rates in PAR. Therefore, interventions to increase engagement in SC should focus on a stepwise approach from none to partial and finally to long-term participation.

Predictive approach of health indicators from the physical activity habits of active youth

The aim of this study is to analyse the relationship between sport modalities practiced, physical fitness, body composition, and healthy habits in an active young population, using a statistical model for prediction. A total of 2255 (1528 boys and 727 girls) children and adolescents aged 6-17 years old who were involved in extracurricular sports from rural areas of Spain participated. Physical fitness was assessed through validated field test and, body composition was determinated using bioelectrical impedance analysis. Adherence to the Mediterranean diet was assessed by KIDMED questionnaire. The general sport variable was significant in VO2max when comparing the invasion and combat modalities to the reference level (court/net). The sex and age variables revealed significant differences in all physical fitness and body composition parameters. Health parameters, such as hours of additional practice, adherence to the Mediterranean diet, and previous experience, showed significant differences. The study concludes that the sport modality variables of training, sex, age, and maturational period have an impact on body composition and fitness parameters in this population. Therefore, by focusing on factors associated with lower values in health indicators, we can prevent health problems during adulthood, such as cardiorespiratory deficits.

Acute Pilates and plyometric exercise in school-based settings improve attention and mathematics performance in high school students

The aim of this study was to examine the effects of acute Pilates and plyometric exercise in a school-based setting on attention and mathematics test performance in high school students. Forty 10th-grade students (21 females and 19 males; age: [15.0 ± 0.5] years, body mass index: [21.4 ± 2.8] kg/m2) participated in this crossover and quasi-experimental study. In week 1, students were familiarized with the d2 test of attention and Pilates and plyometric exercises activities, and body composition measurements were taken. In both weeks 2 and 3, students completed the d2 test of attention and mathematics test with 20 questions following a single session of low-to-moderate-intensity exercise and a classroom-based non-exercise activity, in a non-randomized order. The exercise sessions included 30 mins of plyometric exercises for male students and Pilates exercise for female students, with intensities corresponding to 10-14 on the Borg rating of perceived exertion scale6-20. Compared to the non-exercise activity, a 30-min of Pilates and plyometric exercise resulted in significant improvements in attention score (mean difference [Δ] ​= ​54.5 score; p ​< 0.001; Cohen's effect sizes [d] ​= ​1.26) and concentration performance (Δ ​= ​20.7 score; p ​= ​0.003; d ​= ​0.51). The students scored significantly higher on the mathematics test after participating in the exercise sessions compared to the non-exercise condition (Δ% ​= ​11.7; p ​< ​0.001; d ​= ​0.76). There were no significant differences between genders (p ​> ​0.05). These findings demonstrate the effectiveness of acute light-to-moderate-intensity Pilates and plyometric exercises in school-based settings for improving attention and mathematics performance in adolescents.

Muscular fitness profiles in relation to the response in body fat during school-based high-intensity intervention

BACKGROUND

We aimed to assess the equivalence of the muscular fitness (MF) between body fat percentage (BFP) responders (RsBFP) and non-responders (NRsBFP) to school-based high-intensity interval training (HIIT). Adolescents aged 16 (N.=73, 42.5% of males) were identified as RsBFP (N.=45) or NRsBFP (N.=28). MF was assessed based on hand strength (HS), abdominal muscle strength (ABS), and leg power (VJ).

METHODS

Profile analysis showed distinct patterns of MF changes in both response categories. Despite the presence of parallelism (Wilks' Λ=0.979, Pillai's V=0.212, P=0.473), a gradient of increasing changes (HS-ABS-VJ) was found in the RsBFP, while a gradient of decreasing changes was shown in the NRsBFP, and a significant level of inequality (F(1,71)=7.823, P=0.047, partial eta-squared [η2p] 0.041).

RESULTS

One-way analysis showed a significant and moderate effect on VJ (F(1,71)=7.080, P=0.010, η2P=0.091), a close to significant effect on ABS (F(1,71)=3.300, P=0.074, η2P=0.044) and lack of an effect on HS (F(1,71)=0.699, P=0.406, η2P=0.010). The test of equal means across the condition categories (separately for RsBFP and NRsBFP) indicated that there was no multivariate statistically significant within-group effect (F(2, 70)=0.517, P=0.599).

CONCLUSIONS

The findings may help teachers assess the potential and indirect changes in muscle performance after employing a body weight intervention (based on the HIIT program). A more targeted approach to treating adolescents with excessive BF, in parallel with improving MF, can be individually tailored.

Longitudinal Associations Between Enjoyment of Physical Education, Cardiorespiratory Fitness, and Muscular Fitness Among Finnish Adolescents

INTRODUCTION

Students' experiences in physical education (PE) can shape future physical activity (PA) behaviors. PE enjoyment is associated with PA; however, the relationship between PE enjoyment and fitness has not been extensively investigated. The aim of this study was to examine if changes in PE enjoyment were associated with changes in cardiorespiratory fitness (CRF) and muscular fitness (MF) among Finnish adolescents.

METHODS

Study participants were students (n = 1147; 11.27 [±0.32] years at baseline) attending public schools in Finland. Data were collected yearly (2017-2021). The 20 m shuttle run assessed CRF, curl-up/push-up tests assessed MF, and the enjoyment subscale of the Sport Commitment Questionnaire-2 measured PE enjoyment. The random intercept cross-lagged panel model, including repeated measures (within-level) and latent levels (between-level) of PE enjoyment, CRF and MF, was tested. Sex, body mass index, moderate to vigorous PA, and peak height velocity were included as covariates in the analysis.

RESULTS

Over 5 years, PE enjoyment decreased, CRF increased until Timepoint 3, and MF remained stable. Positive associations between PE enjoyment and fitness were observed, indicating the greater the PE enjoyment, the higher the fitness. For PE enjoyment, CRF and MF repeated measures were positively associated with measurement of the next year. PE enjoyment was positively related to CRF and MF the years thereafter.

CONCLUSION

Our findings highlight the importance of quality PE experiences for enjoyment and fitness gains during the transition from primary to secondary school. These findings are important given youth fitness levels are associated with future health status.

Temporal trends and distributional changes in cardiorespiratory fitness among Chinese children and adolescents from 1985 to 2019

OBJECTIVES

The aim of this study was to analyze the temporal trends in cardiorespiratory fitness (CRF) and body mass index (BMI) among children and adolescents from 1985 to 2019.

METHODS

A total of 1 840 212 children and adolescents aged 7-18 years (921 223 boys) were tested for CRF from 1985 to 2019. CRF was tested by 50-m × 8 shuttle run for boys and girls aged 7-12 years, 1000-m run for boys aged 13-18 years, and 800-m run for girls aged 13-18 years. Trends in BMI from 2000 to 2019 were also investigated.

RESULTS

Cardiorespiratory fitness decreased during the entire 34 years among children and adolescents in all sex and age categories, and the most rapid decline occurred from 1995 to 2005. Some positive trends in CRF were observed among adolescents aged 13-15 years from 2005 to 2019 and among girls aged 16-18 years from 2014 to 2019. The variation in the CRF distribution was not uniform, with Z-scores for participants with high CRF levels changing little or increasing (CRF stabilized or improved) and Z-scores for participants with low CRF levels continuing to decrease (CRF decreased). BMI increased over time for boys and girls in all age categories, with an acceleration of the increase for adolescents in recent years.

CONCLUSIONS

This study revealed that the overall CRF levels of Chinese children and adolescents decreased over three decades but stabilized or improved in recent years. BMI continued to increase. Our findings are important for the focus on future domestic physical fitness and public health.

Effects of 16-week circuit training on physical fitness parameters, pulmonary function, and quality of life in healthy women

BACKGROUND

Circuit training (CT) is an important type of training that can combine different types of exercises in a single form of training. This study aimed to investigate the effects of 16-week CT on physical fitness parameters, pulmonary function, and quality of life in healthy women.

METHODS

Twenty-nine healthy women (median age: 37.00 [31.50/39.50] years) were included in the study. CT was applied to the participants for a total of 16 weeks. Participants' body composition with the Bioelectrical Impedance Analysis System, knee flexor and extensor muscle strength with the Biodex System-4 Pro, flexibility with the sit-and-reach test, pulmonary function with a spirometer device, and quality of life with Short Form-36 were assessed.

RESULTS

A significant difference was found between the participants' pretest and posttest median and interquartile range values of waist-hip ratio, body mass index, right/left knee flexor/extensor mean peak torque (60°/s,180°/s), right hamstring/quadriceps (H/Q) ratio (60°/s), flexibility, and SF-36 Mental Health Score (P˂0.050). There was no significant difference between the participants' pretest and posttest median and interquartile range values of total body fat, fat percentage, right H/Q ratio (180°/s), left H/Q ratio (60°/s,180°/s), pulmonary function, and Short Form-36 Physical Function Score (P˃0.050).

CONCLUSIONS

CT decreased waist-hip ratio and body mass index, increased knee flexor/extensor strength and flexibility, and improved mental health. The 16-week CT may be an alternative approach to improve physical fitness parameters and mental health without any positive effects on body fat and pulmonary functions in healthy women.

Assessing basic motor competences, physical fitness, and executive function in 4-5-year-old children: a longitudinal study in a primary care setting

BACKGROUND

To evaluate the progression of physical fitness (PF), basic motor competence (BMC), and executive function (EF) over one year in children aged 4-5 years at a health center.

METHODS

In this longitudinal analysis, children's BMC was evaluated using the MOBAK KG test for object and self-movement. The PREFIT Battery gauged PF through handgrip strength, standing long jump, and other fitness measures, while the Early Years Toolbox appraised EF.

RESULTS

Adjustments for confounding factors showed notable improvements in BMC, particularly in object movement (OM; mean difference 0.789, p = 0.044) and self-movement (SM; mean difference 0.842, p = 0.037), with overall MOBAK scores also increasing (mean difference 1.632, p = 0.018). Enhancements in the standing long jump (mean difference 9.036 cm, p = 0.014) and EF tasks "Mr. Ant" (mean difference 0.669, p < 0.001) and "Go/No-Go" (mean difference 0.120, p < 0.001) were evident, signifying substantial BMC gains and some progress in PF and EF.

CONCLUSION

This research underscores the positive impact of regular training on BMC and PF in young children. Significant BMC development and associated improvements in PF and EF over the study period highlight the importance of structured activities in early childhood. These findings advocate for standardized training programs to enhance childhood health and encourage active lifestyles.

TRIAL REGISTRATION

NCT05741879. Registered February 14, 2023, Version 1.

Anthropometric Influence on Preschool Children's Physical Fitness and Motor Skills: A Systematic Review

Early childhood is a critical period for physical and motor development with implications for long-term health. This systematic review examined the relationship between anthropometric characteristics and measures of physical fitness and motor skills in preschool-aged children (typically 2-6 years). The search strategy was applied in four databases (PubMed, ProQuest Central, Scopus, and Web of Science) to find articles published before 11 April 2024. The results consistently demonstrated significant associations between anthropometric variables (height, weight, body mass index [BMI], body composition) and physical performance measures. Notably, height and mass were often better predictors of fitness status than BMI alone. Indicators of undernutrition (stunting, wasting) were negatively associated with motor development, emphasizing the importance of adequate nutrition. While some studies reported impaired fitness and motor skills among overweight/obese preschoolers compared to normal-weight peers, others found no differences based on weight status. Relationships between physical activity levels, anthropometrics, and motor outcomes were complex and inconsistent across studies. This review highlights key findings regarding the influence of anthropometric factors on physical capabilities in early childhood. Early identification of children with impaired growth or excessive adiposity may inform tailored interventions to promote optimal motor development and prevent issues like obesity. Creating supportive environments for healthy growth and age-appropriate physical activity opportunities is crucial during this critical developmental window.

A multimodal approach integrating cognitive and motor demands into physical activity for optimal mental health: Methodological issues and future directions

Physical activity is known for its positive effects on cognition and affect, with existing literature suggesting that these mental health benefits may be optimally experienced by incorporating cognitive and motor demands during physical activity (PA). However, the existing body of literature lacks a comprehensive guideline for designing the qualitative characteristics of a PA program. Accordingly, this narrative review aimed to (1) provide a working two-dimension model that operationally defines the cognitive and motor demands involved in PA and the rationale for systematically studying these qualitative aspects of PA, (2) identify methods to assess the cognitive and motor demands of PA and address associated methodological issues, and (3) offer potential future directions for research on the cognitive and motor aspects of PA in support of the development of PA programs designed to maximize PA-induced cognitive and affective benefits. We anticipate this article to inform the need for future research and development on this topic, aiming to create clear, evidence-based guidelines for designing innovative and effective PA interventions.

The effect of physical fitness on psychological health: evidence from Chinese university students

BACKGROUND

Despite frequent discussions on the link between physical and mental health, the specific impact of physical fitness on mental well-being is yet to be fully established.

METHOD

This study, carried out between January 2022 and August 2023, involved 4,484 Chinese University students from eight universities located in various regions of China. It aimed to examine the association between physical fitness on psychological well-being. Descriptive statistics, t-tests, and logistic regression were used to analyze the association between physical fitness indicators (e.g., Body Mass Index (BMI), vital capacity, and endurance running) and mental health, assessed using Symptom Checklist-90 (SCL-90). All procedures were ethically approved, and participants consented to take part in.

RESULTS

Our analysis revealed that BMI, vital capacity, and endurance running scores significantly influence mental health indicators. Specifically, a 1-point increase in BMI increases the likelihood of an abnormal psychological state by 10.9%, while a similar increase in vital capacity and endurance running decreases the risk by 2.1% and 4.1%, respectively. In contrast, reaction time, lower limb explosiveness, flexibility, and muscle strength showed no significant effects on psychological states (p > 0.05).

CONCLUSION

Improvements in BMI, vital capacity, and endurance running capabilities are associated with better mental health outcomes, highlighting their potential importance in enhancing overall well-being.

Adolescent mental health and cardiorespiratory fitness: A comparison of two cohorts 12 years apart

The aim of the study was to compare the mental health and cardiorespiratory fitness (CRF) of adolescents in two cross-sectional cohorts, one measured in 2003 and the other in 2015, both at age 15 and across sexes. The study also sought to estimate the association between mental health and CRF in the two cohorts and examine the relationship between the level of CRF and mental health in each cohort overall and by sex. Data from 443 participants born in 1988 (228 males, 215 females) and 303 participants born in 1999 (126 males, 177 females) were analyzed. Mental health was assessed using self-reports of body image, self-esteem, and symptoms of depression and anxiety. CRF was estimated using a maximal cycle ergometer test. From 2003 to 2015, body image scores improved (p = .043), self-esteem remained stable, and CRF declined significantly (p < .001). No self-esteem differences were observed between sexes in any cohort. Males had higher CRF and body image scores than females in both cohorts (p < .001 for all comparisons). Higher CRF correlated with fewer depressive symptoms across sexes and cohorts. Specifically, higher CRF was associated with anxiety in females and improved body image in males (2003) and both sexes (2015). Increased CRF was linked to higher self-esteem in females but not in males. Overall, higher CRF levels were associated with better mental health outcomes for both sexes. These results highlight the potential of improving adolescent mental health through increased physical fitness.

Comparison of physical activity and physical fitness in children and adolescents of Chinese Han and Tibet ethnicity

Background

Physical activity (PA) and physical fitness (PF) are important markers of health status in children and adolescents in different ethnicities. In this study, we aimed to compare the PA and PF indicators between Tibetan and Han children and adolescents.

Methods

Children and adolescents of 4-9 grades were recruited in Shigatse (n = 963) and Shanghai (n = 2,525) respectively. The information related to demographic, PA, and PF was collected via a self-reported questionnaire. PA was assessed through the participation of moderate to vigorous PA (MVPA), muscle-strengthening exercise (MSE) and organized sport participation (OSP). PF was estimated using the International Fitness Scale containing components of overall fitness, cardiorespiratory fitness, speed and agility, muscular strength and flexibility.

Results

Han (mean age = 13.45 ± 3.3 years; 49.7% girls) and Tibet (mean age = 13.8 ± 2.5 years; 48.3% girls) children and adolescents from Shanghai and Shigatse completed the questionnaire survey. It was revealed that Tibetan students had higher MVPA, MSE and OSP than children and adolescents of Han ethnicity (p < 0.01, small to medium effect size). A relatively higher percentage of student in Shanghai did not participate in any form of PA. On the other hand, less Tibetan students thought their PF indicators including overall fitness, cardiorespiratory fitness, speed and agility, muscular strength and flexibility were poor or very poor than their counterparts of Han ethnicity (p < 0.01, small to medium effect size).

Conclusion

Tibetan children and adolescents have higher levels of PA and PF in comparison to their Han counterparts. More children and adolescents of Han ethnicity engage in no PA and think their PF indicators were poor.

Association between Gross Motor Competence and Physical Fitness in Chilean Children Aged 4 to 6 Years

The preschool period is considered critical for the development of motor competence, but as far as we know, no studies have investigated the association between motor competence and physical fitness in Chilean children. The aim of this study was to analyse the association between gross motor competence and physical fitness, controlling for possible confounding factors. A cross-sectional study was conducted with a sample of 144 preschool children (56.25% girls) with an average age of 5.3 years (4 to 6 years) from the Araucanía region, Chile. Motor competence was measured using the Children's Movement Assessment Battery, 2nd Edition (MABC-2). Regarding physical fitness, the components of cardiorespiratory fitness, lower body muscle strength and speed/agility were evaluated using the Battery to Assess FITness in PREschool (PREFIT). Partial correlation models and analysis of variance (ANCOVA) were used to assess differences in physical fitness between motor competence categories, controlling for age and body mass index. The mean fitness scores for cardiorespiratory fitness, lower body muscle strength and speed/agility components were significantly higher in children with higher gross motor competence. In terms of effect size, large values were found for the lower body strength component in model 1 for boys and in model 2 for the total samples of girls and boys. The results of this study suggest that good levels of gross motor competence are associated with better physical fitness levels.

Reduced exercise capacity for muscle mass in adolescents living with obesity

BACKGROUND

Adolescents living with obesity (AlwO) can have limited exercise capacity. Exercise capacity can be predicted by a 2-factor model comprising lung function and leg muscle function, but no study has looked at cycling leg muscle function and its contribution to cycling exercise capacity in AlwO.

METHODS

Twenty-two nonobese adolescents and 22 AlwO (BMI > 95 percentile) were studied. Anthropometry, body composition (dual-energy X-ray absorptiometry), spirometry, 30-s isokinetic work capacity, and maximal exercise (cycle ergometry) were measured.

RESULTS

AlwO had greater total body mass, lean body mass, and lean leg mass (LLM). Lung function trended higher in AlwO. Leg 30-s work did not differ in absolute terms or per allometrically scaled LLM. Peak oxygen consumption did not differ between the groups in absolute terms or as percent predicted values (79.59 ± 14.6 vs. 82.3 ± 11.2% predicted control versus ALwO) but was lower in AlwO when expressed per kg body mass, kg lean body mass, scaled lean body mass, and LLM. Peak oxygen consumption related to both lung function and 30-s work, with no observed group effect. 30-s leg work related to the scaled LLM, with a small group effect. There was some correlation between leg work and time spent in moderate to vigorous physical activity in AlwO (rs = 0.39, p = .07).

CONCLUSION

AlwO have larger LLM and preserved exercise capacity, when expressed as percentage of predicted, but not per allometrically scaled LLM. Increasing time spent in moderate to vigorous activity may benefit AlwO.

Secular trends and sociodemographic, biological, and behavioural factors associated with handgrip strength in adolescents in southern Brazil: An allometric approach

The purpose of this study was to analyse secular trend in handgrip strength (HGS) in adolescents using an allometric approach and identify the factors associated. The sample comprised 657 and 1004 adolescents (14 to 19 years) in 2007 and 2017/2018, respectively, of public schools in Florianópolis, Brazil. The dependent variable was HGS normalised to body mass and height. Covariance analysis was used to examine secular trends in HGS, and multiple linear regression was used to identify associated factors. The independent variables were sociodemographic, biological, and behavioural factors. Comparison of HGS between surveys indicated a negative secular trend in both sexes (p < 0.001). In boys, there was a positive association of HGS with age and FFM in both surveys. In 2017/18, there was a positive association with sexual maturation and a negative association with sitting time and fat percentage. In girls, FFM was positively associated with HGS in both surveys. In 2007, there were positive associations of HGS with age and vigorous physical activity, whereas, in 2017/18, negative associations were observed with economic level and sitting time. The findings of the present study show a decline in adolescent HGS. And behavioural changes appear to be contributing to declines in HGS.

Cardiorespiratory and Muscular Fitness in Children and Adolescents with Obesity

PURPOSE OF REVIEW

Examine the current state of literature related to the impact of obesity in children and adolescents on health-related physical fitness and the resultant cardiometabolic disease risk.

RECENT FINDINGS

Cardiorespiratory fitness of children and adolescents has declined over the past few decades which corresponds with an increase in obesity rates. Children with obesity are more likely to have low cardiorespiratory fitness which is associated with higher cardiometabolic disease risk and poorer mental health. The impact of obesity on muscular fitness in children and adolescents is more difficult to ascertain, but in general measures of physical function are lower in children with obesity which has also been associated with higher cardiometabolic disease risk. Components of health-related physical fitness are trending negatively in children and adolescents and appear to be related to the increase in prevalence of obesity. The resultant cardiometabolic disease risk has also risen which suggests a greater disease burden in the future. These disparaging findings highlight the need for aggressive interventions to improve physical fitness in children and adolescents.

Impact of COVID-19 Pandemic Lockdown on Body Mass Index and Physical Fitness in Chinese College Students

PURPOSE

To explore the impact of COVID-19 pandemic lockdown (CoPL) on body mass index (BMI) and physical fitness among college students.

METHODS

Two one-year cohorts, one with no pandemic lockdown (NoPL) exposure and one with CoPL exposure, were included. Baseline measurements were performed in October 2018 (NoPL) and October 2019 (CoPL), and follow-up data were collected one year later. Participants were divided into "deterioration", "no-change", and "improvement" groups based on their quartile distribution of one-year differences (follow-up-baseline) for lower 25%, middle 50%, and upper 25%. Baseline-category logit regression models were used to determine the odds ratios of deterioration and improvement in BMI and physical fitness, with "no-change" used as baseline.

RESULTS

A total of 2,594 and 2,525 students were included in NoPL and CoPL cohorts, respectively. CoPL was associated with higher odds for deterioration in BMI (male), explosive strength, upper-limb muscle strength, abdominal muscle strength, and cardiorespiratory fitness, but lower odds for deterioration in BMI (female) and flexibility. CoPL was associated with lower odds for improvement in BMI (male), explosive strength, lower-limb and upper-limb muscle strength, and cardiorespiratory fitness, but higher odds for improvement in BMI (female) and flexibility.

DISCUSSION

Not all dimensions of health outcomes were negatively impacted by the lockdown, as deterioration in BMI in males, muscle strength, and cardiorespiratory fitness following the CoPL were more than that in the absence of the lockdown, while deterioration in BMI in females and flexibility were less than that in the absence of the lockdown.

Is change of direction influenced by motor competencies? A possible response from a MOBAK-based study in Italian schoolchildren

BACKGROUND

Change of direction (COD) ability requires higher motor control capacity and helps children improve individual motor skills. Likewise, basic motor competencies (BMC) are relevant during child maturation and may interleave with COD ability. This study aimed to investigate the possible individual determinants between the COD ability and the BMC, cognitive skills, and anthropometrics characteristics in Italian primary school children aged 6 to 11.

METHODS

Children of both sexes (N.=221) were recruited from primary schools (grade 1 to 5) of Northwestern Italy. COD was assessed by 10×5 m Shuttle Run Test; motor coordination by the Motor Coordination (Motorische Basiskompetenzen, MOBAK) 1-6 test battery, whereas Trail Making Test was used to assess cognitive performance.

RESULTS

A stepwise linear regression indicated that motor competencies level - assessed by the MOBAK Test - is the most fitting dimension describing COD performance for girls, with the highest R2 in Grade 5 (SEE=0.56); and the lowest SEE in Grade 5 (SEE=1.44); moreover, for boys the highest in Grade 3 (SEE=0.52) and the lowest SEE in Grade 4 (SEE=1.30).

CONCLUSIONS

This study confirms the biunivocal relationship between COD and BMC, and the need for physical education teachers and trainers to stimulate both, during growth.

Muscle strength deficits are associated with low bone mineral density in young pediatric cancer survivors: The iBoneFIT project

BACKGROUND

Pediatric cancer survivors are at increased risk of muscle weakness and low areal bone mineral density (aBMD). However, the prevalence of muscle strength deficits is not well documented, and the associations of muscle strength with aBMD are unknown in this population. Therefore, this study aimed to investigate the prevalence of upper- and lower-body muscle strength deficits and to examine the associations of upper- and lower-body muscle strength with age-, sex, and race-specific aBMD Z-scores at the total body, total hip, femoral neck, and lumbar spine.

METHODS

This cross-sectional study included 116 pediatric cancer survivors (12.1 ± 3.3 years old, mean ± SD; 42.2% female). Upper- and lower-body muscle strength were assessed by handgrip and standing long jump test, respectively. Dual‑energy X‑ray absorptiometry was used to measure aBMD (g/cm2). Associations between muscle strength and aBMD were evaluated in multivariable linear regression models. Logistic regression was used to evaluate the contribution of muscle strength (1-decile lower) to the odds of having low aBMD (Z-score ≤ 1.0). All analyses were adjusted for time from treatment completion, radiotherapy exposure, and body mass index.

RESULTS

More than one-half of survivors were within the 2 lowest deciles for upper- (56.9%) and lower- body muscle strength (60.0%) in comparison to age- and sex-specific reference values. Muscle strength deficits were associated with lower aBMD Z-scores at all sites (B = 0.133-0.258, p = 0.001-0.032). Each 1-decile lower in upper-body muscle strength was associated with 30%-95% higher odds of having low aBMD Z-scores at all sites. Each 1-decile lower in lower-body muscle strength was associated with 35%-70% higher odds of having low aBMD Z-scores at total body, total hip, and femoral neck.

CONCLUSION

Muscle strength deficits are prevalent in young pediatric cancer survivors, and such deficits are associated with lower aBMD Z-scores at all sites. These results suggest that interventions designed to improve muscle strength in this vulnerable population may have the added benefit of improving aBMD.

Cardiorespiratory fitness has declined among French children since 1999, although the decline appears to be getting smaller

BACKGROUND

Cardiorespiratory fitness (CRF) is a strong marker of current and future health. The aim of this study was to assess the national temporal trends in CRF for French children and adolescents between 1999 and 2022.

METHODS

CRF data were obtained from several cross-sectional studies on 15 420 (51.1% boys) French children and adolescents aged 9-16 years between 1999 and 2022. The 20-m shuttle run test (20mSRT) estimated CRF. Body mass index (BMI) was calculated from measured height and body mass, with BMI z-scores (BMIz) calculated using WHO growth curves. The 20mSRT results were corrected for protocol and converted to z-scores (20mSRTz) using international sex- and age-specific norms. With additional adjustment for BMIz, temporal trends in mean 20mSRT performance (20mSRTz) were estimated using linear regression, with the distance max (Dmax) method used to locate a breakpoint and linear segments fitted to points below and above the breakpoint. Trends in distributional characteristics were assessed visually and described as the ratio of the coefficients of variation (CVs).

RESULTS

After adjustment for protocol, age, sex, and BMIz, a large decline in mean 20mSRT performance (trend per decade (95% CI): -1.42 SDs (-1.45, -1.39) or -18.4% (95% CI: -18.8, -18.0)) between 1999 and 2022 was found. Dmax located a breakpoint for the two-linear-segment model in year 2010. There was a large decline in mean 20mSRT performance pre-2010 (trend per decade (95% CI): -2.31 SDs (-2.39, -2.24)), which reduced 0.06-fold to a negligible decline post-2010 (trend per decade (95% CI): -0.15 SD (-0.20, -0.10)). We also found that the trend in mean 20mSRT performance was not uniform across the population distribution. Between 1999 and 2022, there was a small trend in distributional asymmetry, with slightly smaller declines experienced by the high performers (above the 75th percentile).

CONCLUSIONS

Our data suggest a large decline in the 20mSRT performance of French children and adolescents since 1999. This declining trend seems to have diminished considerably since 2010. Such declines in CRF could translate into declines in health status. Although a slowing in the declining trend in CRF in recent years is encouraging, more data are needed to confirm these findings.

Effectiveness of mHealth App-Based Interventions for Increasing Physical Activity and Improving Physical Fitness in Children and Adolescents: Systematic Review and Meta-Analysis

BACKGROUND

The COVID-19 pandemic has significantly reduced physical activity (PA) levels and increased sedentary behavior (SB), which can lead to worsening physical fitness (PF). Children and adolescents may benefit from mobile health (mHealth) apps to increase PA and improve PF. However, the effectiveness of mHealth app-based interventions and potential moderators in this population are not yet fully understood.

OBJECTIVE

This study aims to review and analyze the effectiveness of mHealth app-based interventions in promoting PA and improving PF and identify potential moderators of the efficacy of mHealth app-based interventions in children and adolescents.

METHODS

We searched for randomized controlled trials (RCTs) published in the PubMed, Web of Science, EBSCO, and Cochrane Library databases until December 25, 2023, to conduct this meta-analysis. We included articles with intervention groups that investigated the effects of mHealth-based apps on PA and PF among children and adolescents. Due to high heterogeneity, a meta-analysis was conducted using a random effects model. The Cochrane Risk of Bias Assessment Tool was used to evaluate the risk of bias. Subgroup analysis and meta-regression analyses were performed to identify potential influences impacting effect sizes.

RESULTS

We included 28 RCTs with a total of 5643 participants. In general, the risk of bias of included studies was low. Our findings showed that mHealth app-based interventions significantly increased total PA (TPA; standardized mean difference [SMD] 0.29, 95% CI 0.13-0.45; P<.001), reduced SB (SMD -0.97, 95% CI -1.67 to -0.28; P=.006) and BMI (weighted mean difference -0.31 kg/m2, 95% CI -0.60 to -0.01 kg/m2; P=.12), and improved muscle strength (SMD 1.97, 95% CI 0.09-3.86; P=.04) and agility (SMD -0.35, 95% CI -0.61 to -0.10; P=.006). However, mHealth app-based interventions insignificantly affected moderate to vigorous PA (MVPA; SMD 0.11, 95% CI -0.04 to 0.25; P<.001), waist circumference (weighted mean difference 0.38 cm, 95% CI -1.28 to 2.04 cm; P=.65), muscular power (SMD 0.01, 95% CI -0.08 to 0.10; P=.81), cardiorespiratory fitness (SMD -0.20, 95% CI -0.45 to 0.05; P=.11), muscular endurance (SMD 0.47, 95% CI -0.08 to 1.02; P=.10), and flexibility (SMD 0.09, 95% CI -0.23 to 0.41; P=.58). Subgroup analyses and meta-regression showed that intervention duration was associated with TPA and MVPA, and age and types of intervention was associated with BMI.

CONCLUSIONS

Our meta-analysis suggests that mHealth app-based interventions may yield small-to-large beneficial effects on TPA, SB, BMI, agility, and muscle strength in children and adolescents. Furthermore, age and intervention duration may correlate with the higher effectiveness of mHealth app-based interventions. However, due to the limited number and quality of included studies, the aforementioned conclusions require validation through additional high-quality research.

TRIAL REGISTRATION

PROSPERO CRD42023426532; https://tinyurl.com/25jm4kmf.

Associations of physical fitness with cortical inhibition and excitation in adolescents and young adults

Objective

We investigated the longitudinal associations of cumulative motor fitness, muscular strength, and cardiorespiratory fitness (CRF) from childhood to adolescence with cortical excitability and inhibition in adolescence. The other objective was to determine cross-sectional associations of motor fitness and muscular strength with brain function in adolescence.

Methods

In 45 healthy adolescents (25 girls and 20 boys) aged 16-19 years, we assessed cortical excitability and inhibition by navigated transcranial magnetic stimulation (nTMS), and motor fitness by 50-m shuttle run test and Box and block test, and muscular strength by standing long jump test. These measures of physical fitness and CRF by maximal exercise were assessed also at the ages 7-9, 9-11, and 15-17 years. Cumulative measures of physical measures were computed by summing up sample-specific z-scores at ages 7-9, 9-11, and 15-17 years.

Results

Higher cumulative motor fitness performance from childhood to adolescence was associated with lower right hemisphere resting motor threshold (rMT), lower silent period threshold (SPt), and lower motor evoked potential (MEP) amplitude in boys. Better childhood-to-adolescence cumulative CRF was also associated with longer silent period (SP) duration in boys and higher MEP amplitude in girls. Cross-sectionally in adolescence, better motor fitness and better muscular strength were associated with lower left and right rMT among boys and better motor fitness was associated with higher MEP amplitude and better muscular strength with lower SPt among girls.

Conclusion

Physical fitness from childhood to adolescence modifies cortical excitability and inhibition in adolescence. Motor fitness and muscular strength were associated with motor cortical excitability and inhibition. The associations were selective for specific TMS indices and findings were sex-dependent.

The impact of exercise on the gut microbiota in middle-aged amateur serious runners: a comparative study

Introduction

Exercise, health, and the gut microbiota (GM) are strongly correlated. Research indicates that professional athletes, especially ultra-marathon runners, have unique GM characteristics. However, more research has focused on elite athletes, with little attention given to amateur sports enthusiasts, especially those in the middle-aged population. Therefore, this study focuses on the impact of long-term running on the composition and potential functions of the GM in middle-aged individuals.

Methods

We compared the GM of 25 middle-aged serious runnerswith 22 sedentary healthy controls who had minimal exercise habitsusing 16S rRNA gene sequencing. Additionally, we assessed dietary habits using a food frequency questionnaire.

Results and Discussion

Statistical analysis indicates that there is no significant difference in dietary patterns between the control group and serious runners. Diversity analysis results indicate that there is no significant difference in α diversity between the two groups of GM, but there is a significant difference in β diversity. Analysis of the composition of GM reveals that Ruminococcus and Coprococcus are significantly enriched in serious runners, whereas Bacteroides, Lachnoclostridium, and Lachnospira are enriched in the control group. Differential analysis of functional pathway prediction results reveals significant differences in the functional metabolism levels of GM between serious runners and the control group. Further correlation analysis results indicate that this difference may be closely related to variations in GM. In conclusion, our results suggest that long-term exercise can lead to changes in the composition of the GM. These changes have the potential to impact the overall health of the individual by influencing metabolic regulation.

The concurrent validity and test-retest reliability of a submaximal exercise test in adolescents with autism

PURPOSE

There is a need for valid and reliable clinical assessment tools to assess cardiorespiratory fitness (CRF) levels in adolescents with autism. Therefore, this study aimed to examine the concurrent validity and test-retest reliability of the Astrand-Rhyming Test (ART) in this population.

MATERIALS AND METHODS

45 adolescents with autism aged 12-18 years (n = 32 males, 14.47 ± 1.79 years) performed the ART twice (test-retest reliability) and completed a maximal cardiopulmonary exercise test (CPET) (concurrent validity). Reliability parameters included Pearson correlations, intraclass correlation coefficients (ICCs), standard error of measurements (SEM), minimal detectable changes (MDC), coefficients of variation, paired sample t-tests, linear regressions and Bland-Altman plots. The concurrent validity was evaluated with Pearson correlations, ICCs, paired sample t-tests, linear regressions and Bland-Altman plots.

RESULTS

Strong test-retest reliability (r = 0.84-0.85, ICC = 0.84-0.85) was found for the ART, but the wide limits of agreement intervals suggest the presence of substantial variability. The large SEM (4.73-5.08 mL/kg/min) and MDC (13.20-14.07 mL/kg/min) values suggest lower absolute reliability. Moderate to strong levels of association (r = 0.74-0.75) and agreement (ICC = 0.59-0.66) were found between estimated (ART1) and measured (CPET) VO2 max levels, but significant systematic differences (5.71-8.82 mL/kg/min) were observed.

CONCLUSION

The ART is an accessible and promising method to monitor submaximal CRF levels over time but is less appropriate to estimate maximal CRF levels in this population.