Health-related fitness assessment in childhood and adolescence: a European approach based on the AVENA, EYHS and HELENA studies

Comparison of Estonian Schoolchildren's Physical Activity and Fitness Indicators before and after the COVID-19 Pandemic's Period of Restricted Mobility

It is recognized that the time adolescents spend on physical activity, and the corresponding physical fitness indicators, have diminished over time. However, the exact impact of the COVID-19 pandemic restriction period on physical activity and health-related physical fitness indicators remains unclear. This study sought to determine if and to what degree the primary indicators of physical activity (exercise frequency, exercise intensity, and outdoor physical activity) and health-related physical fitness (strength and endurance) among schoolchildren have shifted, by comparing data from before and after the coronavirus pandemic period. Students aged 12-17 years took part in the study. The physical activity questionnaire and fitness tests were conducted in the autumn of 2017 and spring of 2022. The main results show that moderate- and vigorous-intensity physical activity time and time spent actively outdoors have decreased among adolescents (p < 0.05). There were no significant changes in exercise frequency (p > 0.05). However, there was a statistically significant decline in strength (standing broad jump, bent arm hang) (p < 0.05) and endurance (20 m shuttle run, curl-up) (p < 0.01) when comparing results from before and after the COVID-19 pandemic restriction period. In conclusion, restricted mobility had the greatest impact on the time spent outdoors and, in turn, on physical fitness.

Efficacy of accommodating variable-resistance training on muscle architecture, peak torque, and functional performance in patients with juvenile idiopathic arthritis: A randomized controlled trial

Purpose

This study sought to find out if a 6-week accommodating variable-resistance (AcVR) training might enhance muscle architecture, peak torque, and functional performance in patients with juvenile idiopathic arthritis (Juv-IA).

Methods

Fifty-eight patients with polyarticular Juv-IA (aged 12-18 years) were involved in a randomized controlled trial. They were allocated into two groups: the AcVR group (n = 29; underwent AcVR training, and the control group (n = 29; received the usual exercise regimen). Interventions were applied three times a week over six consecutive weeks. Measurements were done at baseline and after the intervention. The primary outcome measures were muscle architecture and peak torque, with functional capacity being the secondary measure.

Results

Compared to the control group, the AcVR group showed favorable pre-to-post changes in muscle architecture [fascicle length (P = 0.0007, η2p = .18), pennation angle (P = 0.0004, η2p = .20), and muscle thickness (P = 0.001, η2p = .17)]. Further, the AcVR group revealed a greater increase in peak concentric torque of knee extensors at angular speeds of 120°/sec [right side (P = 0.0032, η2p = .08); left side (P = 0.039, η2p = .07)] and 180°/sec [right side (P = 0.01, η2p = .11); left side (P = 0.014, η2p = .10)]. Furthermore, The AcVR group achieved more conducive changes in functional performance [6-min walk test (P = 0.003, η2p = .15), timed up and down stair test (P = 0.009, η2p = .12), and 4 × 10 m shuttle run test (P = 0.036, η2p = .08)].

Conclusion

A 6-week AcVR training is potentially effective for improving muscle architectural qualities, enhancing peak muscle torque, and boosting functional performance in patients with Juv-IA without experiencing any detrimental side effects.

A Multidimensional Approach to Talent Identification in Youth Volleyball through Declarative Tactical Knowledge and Functional Fitness

This study aimed to assess which multidimensional performance indexes were the best predictors of talent identification in volleyball. Fifty-five female players (age: 13.8 ± 1.81 years; mass: 55.12 ± 8.12 kg; height: 158.23 ± 7.62 cm) were clustered into two groups according to some physical characteristics (i.e., the first group included players with more favorable performance predictors). Musculoskeletal Fitness (MSF), Functional Motor Competence (FMC), and Declarative Tactical Knowledge (DTK) were measured as multidimensional indexes of performance. Moderate-to-large differences between groups were found for each index in favor of the first group. Regression analyses were performed to examine the variance explained by MSF, FMC, and DTK in the two groups. A model with FMC components explained slightly more variance in the group predictor variables (R2 = 0.53) than a model using only MSF components (R2 = 0.45). Among FMC components, the score of the Throw-and-Catch test resulted in the best predictor (Odds Ratio = 1.58) for determining group selection, followed by the score of the Supine-to-Stand-and-Go test (Odds Ratio = 0.02). An additional model composed by MSF and FMC significant predictors (i.e., functional fitness index) and DTK explained 63% of the variance (R2 = 0.63), and these were significant predictors of group membership (Odds Ratio = 6.32 and Odds Ratio = 1.51, respectively). A more comprehensive multidimensional analysis of youth performances is warranted to identify and monitor the best players in a youth volleyball context.

The Perils of Misinterpreting and Misusing "Publication Bias" in Meta-analyses: An Education Review on Funnel Plot-Based Methods

Publication bias refers to a systematic deviation from the truth in the results of a meta-analysis due to the higher likelihood for published studies to be included in meta-analyses than unpublished studies. Publication bias can lead to misleading recommendations for decision and policy making. In this education review, we introduce, explain, and provide solutions to the pervasive misuses and misinterpretations of publication bias that afflict evidence syntheses in sport and exercise medicine, with a focus on the commonly used funnel-plot based methods. Publication bias is more routinely assessed by visually inspecting funnel plot asymmetry, although it has been consistently deemed unreliable, leading to the development of statistical tests to assess publication bias. However, most statistical tests of publication bias (i) cannot rule out alternative explanations for funnel plot asymmetry (e.g., between-study heterogeneity, choice of metric, chance) and (ii) are grossly underpowered, even when using an arbitrary minimum threshold of ten or more studies. We performed a cross-sectional meta-research investigation of how publication bias was assessed in systematic reviews with meta-analyses published in the top two sport and exercise medicine journals throughout 2021. This analysis highlights that publication bias is frequently misused and misinterpreted, even in top tier journals. Because of conceptual and methodological problems when assessing and interpreting publication bias, preventive strategies (e.g., pre-registration, registered reports, disclosing protocol deviations, and reporting all study findings regardless of direction or magnitude) offer the best and most efficient solution to mitigate the misuse and misinterpretation of publication bias. Because true publication bias is very difficult to determine, we recommend that future publications use the term "risk of publication bias".

Effectiveness of a dose-graded aerobic exercise regimen on cardiopulmonary fitness and physical performance in pediatric survivors of acute lymphoblastic leukemia: a randomized clinical trial

PURPOSE

To determine whether a 12-week supervised dose-graded aerobic exercise (D-GAE) training, when implemented in conjunction with traditional rehabilitation, could help pediatric survivors of acute lymphoblastic leukemia (ALL) enhance their cardiopulmonary capacity and improve their physical performance.

METHODS

Fifty-eight pediatric survivors of ALL (age 13.78 ± 2.47 years; boys 60.34%) were assigned at random to either undergo the D-GAE in addition to the traditional physical rehabilitation (D-GAE group; n = 29) or the traditional physical rehabilitation solely (control group; n = 29). The cardiopulmonary fitness (peak oxygen uptake (VO2peak), ventilatory equivalent (VEq/VO2), minute ventilation (VE, L/min), oxygen pulse (O2P), maximum heart rate (HRmax), 1-min heart rate recovery (HRR1), and respiratory exchange ratio (RER)) and physical performance (6-min walk test (6-MWT), timed up and down stairs (TUDS), and 4 × 10-m shuttle run test (4 × 10mSRT)) were assessed on the pre- and post-intervention occasions.

RESULTS

The mixed-model ANOVA revealed a meaningful increase of VO2peak (P = .002), VE (P = .026), O2P (P = .0009), HRmax (P = .004), and HRR1 (P = .011), and reduction of VEq/VO2 (P = .003) and RER (P = .003) in the D-GAE group compared with the control group. Besides, the analysis detected a favorable increase in the physical performance for the D-GAE group (6-MWT (P = .007), TUDS (P < .001), 4 × 10mSRT (P = .009)).

CONCLUSION

A 12-week D-GAE program in conjunction with traditional rehabilitation holds promise in enhancing cardiopulmonary fitness and improving the physical performance of pediatric survivors of ALL. Clinicians and physical rehabilitation professionals can, therefore, integrate the D-GAE into the traditional rehabilitation protocols for such a patient population to optimize their cardiopulmonary fitness and physical function, while also facilitating a gradual transition to practice and adaption.

IMPLICATIONS FOR CANCER SURVIVORS

The favorable outcomes of this study bolster the inclusion of D-GAE as a crucial element in the care and rehabilitation of pediatric survivors of ALL. By embracing these findings, healthcare professionals and oncologists can contribute to mitigating the long-term cardiopulmonary and physical complications associated with cancer treatments and fostering a state of enhanced well-being and increased physical activity among survivors.

Correlation of fundamental movement skills with health-related fitness elements in children and adolescents: A systematic review

Objective

To examine the correlations between fundamental movement skills and health-related fitness elements (cardiopulmonary function, flexibility, body composition, muscle strength and endurance) in children and adolescents and investigate the evaluation methods and tools of fundamental movement skills and health-related fitness.

Methods

Six electronic databases (Web of Science, PubMed, ProQuest, Scopus, EBSCO and CNKI) were searched, and the research literature on the correlation between children's and adolescents' fundamental movement skills and health-related fitness published since 2002 was collected. The guidelines of the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement and the Consolidated Standards of Reporting Trials (CONSORT) statement were used to evaluate the quality of the literature, and the sources, samples, measurement methods, main results and statistical data of the study were analyzed, summarized and discussed.

Results

After applying the inclusion and exclusion criteria, 49 studies were included. There were 13 tools for evaluating fundamental movement skills and 4 tools for evaluating comprehensive health-related fitness in the included literature. Sufficient research evidence supports a significant positive correlation between fundamental movement skills and cardiopulmonary function (10, 100%) and muscle strength and endurance (12, 100%), and most studies support the positive correlation between fundamental movement skills and flexibility (4, 66.7%), and the significant negative correlation between fundamental movement skills and body composition (29, 67.4%). Studies used skinfold, AF%, BF%, FM, and FFMI as evaluation methods. They showed a consistently significant negative correlation between body composition and fundamental movement skills (9, 100%), while BMI or waist circumference as evaluation methods showed no consistent significant negative correlation result (20, 58.8%). Moreover, in the sub-item evaluation of fundamental movement skills, object manipulation, locomotor and balance skills were all significantly and positively correlated with cardiopulmonary function and muscle strength and endurance. In contrast, locomotor skills were more closely related to body composition than object manipulation skills.

Conclusion

A significant correlation exists between children's and adolescents' fundamental movement skills and health-related fitness elements.

Does incorporating high intensity interval training in physical education classes improve fitness outcomes of students? A cluster randomized controlled trial

The aim of this study was to determine the efficacy of a high intensity interval training (HIIT) intervention lasting 12 weeks on fitness (cardiorespiratory fitness, muscular strength, muscular endurance, power, speed, flexibility, and balance) and adiposity of 10- to 15-year-old students implemented during their physical education (PE). The focus of this study was to compare two approaches to increasing fitness level among school-aged children, one approach focusing on regular PE sessions in accordance with the curriculum and another one on regular PE classes augmented by HIIT. A cluster-randomized controlled trial was conducted (February-May 2022, Zagreb, Croatia). The total number of students across both groups was 207. General linear models were used to compare fitness and adiposity changes in both groups based on Eurofit test battery. A significant effect of the HIIT intervention was present for the 20-meter shuttle run test (p = 0.001; d = 0.31). The effect of the intervention compared to the control was estimated as an additional 181.2 m, 95 %CI (70.4 to 292.0). An additional intention-to-treat (ITT) analysis showed that the effect of the HIIT intervention on 20-meter shuttle run test remained statistically significant (p = 0.011), though the magnitude of the estimated effect was reduced from 181.2 m; SE = 55.4 to 119.6 m; SE = 46.4. Whilst it appears HIIT had the opposite of the expected effect on body fat percentiles, the effect on body composition was inconsistent. The intervention is registered at the Australian New Zealand Clinical Trials Registry (ANZCTR) [ACTRN12622000209796].

Strength versus aerobic program: effects on body composition and health-related physical fitness levels of youths with Down syndrome

Aims: To determine the effect of a 16-week fitness program (strength vs. aerobic) on different indicators of body composition and components of health-related physical fitness in youths with Down syndrome. Methods and procedures outcomes: Fifty adolescents (19 girls and 31 boys; average age, 18.33 ± 1.42 years) with Down syndrome were recruited and randomized to two groups (strength group vs. aerobic group). Adolescents allocated in the aerobic group carried out a physical activity program three times a week for 16 weeks meanwhile adolescents allocated in the strength group performed a fitness program three times a week for 16 weeks. Results: The exercise group had significant improvements in all health-related physical fitness variables (p < .05) but not on body composition. Conclusions and implications: A sixteen week fitness program consisting of three sessions of 60 min is able to increase levels of health-related physical fitness but not on body composition in youths with Down syndrome. The aerobic program does not seem to show significant differences.

Potential Relevance of a Motor Skill “Proficiency Barrier” on Health-Related Fitness in Youth

This study investigated the potential impact of a motor skill proficiency barrier on measures of cardiorespiratory (CRF) and musculoskeletal (MSF) fitness in youth. A sample of 241 youth (114 girls) aged 10 - 18 years, completed the Motor Competence Assessment battery with composite scores indexed according to age- and gender-adjusted percentile scores. Motor competence (MC) levels were categorized as low (≤ 25%tile - proficiency barrier), moderate (≥ 26%tile to < 75%tile), and high (≥ 75%tile). CRF levels (Health Risk, Needs Improvement, and Healthy) were assessed using the Fitnessgram® 20 m PACER test. Low (≤ 20%tile), moderate (≥ 21%tile to ≤ 80%tile), and high (≥ 80%tile) MSF levels were assessed using grip strength normative data. Two 3 × 3 chi-square tests were conducted to determine the probability of MC level predicting CRF and MSF levels. Results demonstrated statistically significant models for performance on both the PACER (χ2[4, N = 241] = 22.65, p < .001) and grip strength (χ2[4, N = 241] = 23.95, p < .001). Strong evidence of a proficiency barrier impacting CRF was noted, as no low skilled youth met the "Healthy" fitness zone standards for PACER performance. Evidence supporting a barrier with grip strength was not as strong, as 20.8% of youth exhibiting low MC displayed high grip strength. However, all individuals with high levels of MC demonstrated at least moderate grip strength. Results emphasize the importance of developing MC during childhood as it may provide a protective effect against unhealthy CRF and MSF across youth.HighlightsThese data support the notion of Seefeldt's (1980) proficiency barrier as it relates to CRF, as no youth demonstrating low MC met the healthy fitness zone criteria for PACER performance. The development of MC may both directly and indirectly provide a protective effect against unhealthy CRF levels across childhood and adolescence.Evidence supporting a proficiency barrier with MSF as measured by grip strength was not as strong; however, all individuals with high levels of MC demonstrated at least moderate grip strength. Thus, the development of MC may be a protective factor to mitigate low levels of MSF via enhanced neuromuscular function.Promoting the development of MC in a variety of developmentally appropriate activities and settings (e.g. MC skills practice, structured and unstructured play, and performance contexts) is important to promote positive trajectories of CRF and MSF across childhood and adolescence.

Health-Related Physical Fitness in Adolescents from Spain, Estonia and Iceland: A Cross-Sectional, Quantitative Study

The benefits of physical fitness (PF) for health are well-known. Low PF significantly contributes to the prevalence of obesity in adolescents, with an increased risk of developing chronic diseases. The objectives of the present study were to explore the health-related PF components and body composition levels in adolescents in three European cities, and their differences. The present study is a cross-sectional, descriptive, and quantitative research effort with 1717 participants aged between 13−16 years (48% girls), enrolled in public and private secondary schools in Seville (Spain), Reykjavik (Iceland) and Tartu (Estonia). The ALPHA fitness battery test was used with the following tests: handgrip strength, standing broad jump, 4 × 10 m speed-agility, 20 m shuttle run, and anthropometric variables. Regarding body composition, differences were detected for city and gender in height (p < 0.001), weight (p < 0.001), body fat percentage (p < 0.001), and waist circumference (p < 0.001); but no differences were reported for BMI for both city (p = 0.150) and gender (p = 0.738). Similarly, concerning PF, it was detected statistically significant differences between cities and gender in handgrip strength (p < 0.001), jump test (p < 0.001), speed-agility test (p < 0.001), and cardiovascular endurance in both variables (p < 0.001). In total, 26.8% of the boys and 27.3% of the girls were categorized as overweight; 18.1% of the boys and 31.2% of the girls had an excessive percentage of fat mass; and 22.7% of the boys and 22.2% of the girls showed an excessive waist circumference. The participants from Seville presented the lowest results in PF tests. In contrast, Reykjavik, with the highest results in the endurance and speed-agility tests, and Tartu, with higher results in the manual grip strength and long jump tests, shared the highest results.

Jump rope training effects on health- and sport-related physical fitness in young participants: A systematic review with meta-analysis

The aim of this systematic review with meta-analysis was to assess the available body of published peer-reviewed articles related on the effects of jump rope training (JRT) compared with active/passive controls on health- and sport-related physical fitness outcomes. Searches were conducted in three databases, including studies that satisfied the following criteria: i) healthy participants; ii) a JRT programprogramme; iii) active or traditional control group; iv) at least one measure related to health- and sport-related physical fitness; v) multi-arm trials. The random-effects model was used for the meta-analyses. Twenty-one moderate-high quality (i.e., PEDro scale) studies were meta-analysed, involving 1,021 participants (male, 50.4%). Eighteen studies included participants with a mean age <18 years old. The duration of the JRT interventions ranged from 6 to 40 weeks. Meta-analyses revealed improvements (i.e., p = 0.048 to <0.001; ES = 0.23-1.19; I² = 0.0-76.9%) in resting heart rate, body mass index, fat mass, cardiorespiratory endurance, lower- and upper-body maximal strength, jumping, range of motion, and sprinting. No significant JRT effects were noted for systolic-diastolic blood pressure, waist-hip circumference, bone or lean mass, or muscle endurance. In conclusion, JRT, when compared to active and passive controls, provides a range of small-moderate benefits that span health- and sport-related physical fitness outcomes.

Identification of Lifestyle Risk Factors in Adolescence Influencing Cardiovascular Health in Young Adults: The BELINDA Study

Cardiovascular diseases are the leading cause of mortality worldwide. These diseases originate in childhood, and a better understanding of their early determinants and risk factors would allow better prevention. The BELINDA (BEtter LIfe by Nutrition During Adulthood) study is a 10−14-year follow-up of the HEalthy Lifestyle in Europe by Nutrition in Adolescence study (the HELENA study, a European cross-sectional study in adolescents). The study aims to evaluate cardiovascular risk using the PDAY (Pathobiological Determinants of Atherosclerosis in Youth) risk score during young adulthood (21−32 years), and to examine the impact of risk factors identified during adolescence (12.5−17.5 years). Our secondary objective is to compare the characteristics of the BELINDA study population with the HELENA population not participating in the follow-up study. The HELENA study recruited 3528 adolescents during 2006−2007 and reassessed 232 of them 10−14 years later as young adults. We assessed clinical status, anthropometry, nutrition, physical activity (including sedentary behavior), physical fitness, and mental health parameters, and collected biological samples (blood, stool, and hair). Dietary intake, and physical activity and fitness data were also collected. A multivariable linear regression model will be used for the analysis of the primary outcome. A Chi-square and T-test were conducted for the comparison of the descriptive data (gender, age, weight, height, body mass index (BMI), and maternal school level) between participating and non-participating BELINDA adolescents. When comparing the 1327 eligible subjects with the 232 included in the BELINDA study, no significant differences regarding gender (p = 0.72), age (p = 0.60), height (p = 0.11), and weight (p = 0.083) at adolescence were found. However, the participating population had a lower BMI (20.4 ± 3.1 kg/m2 versus 21.2 ± 3.6 kg/m2; p < 0.001) and a higher maternal educational level (46.8% high school or university level versus 38.6%; p = 0.027) than the HELENA population who did not participate in the BELINDA study. The complete phenotyping obtained at adolescence through the HELENA study is a unique opportunity to identify adolescent risk factors for cardiovascular diseases. This paper will serve as a methodological basis for future analysis of this study.

Fit to Play? Health-Related Fitness Levels of Youth Athletes: A Pilot Study

ABSTRACT

Pfeifer, CE, Sacko, RS, Ortaglia, A, Monsma, EV, Beattie, PF, Goins, J, and Stodden, DF. Fit to play? Health-related fitness levels of youth athletes: A pilot study. J Strength Cond Res 36(1): 245-251, 2022-A recent National Strength and Conditioning Association position statement suggests that many youth are not prepared for the physical demands of sport. The purpose of this study was to compare health-related fitness (HRF) of youth athletes with normative findings from the general population. We recruited 136 athletes (63 male and 73 female athletes) aged 11-19 (16.01 ± 1.35) years and collected HRF (body composition, cardiorespiratory endurance, musculoskeletal strength and endurance). Results were categorized based on FITNESSGRAM® standards and compared with Canadian youth general population normative data. Most male athletes were classified as "needs improvement" for cardiorespiratory and muscular endurance, and body mass index (BMI). Conversely, most female athletes were at or above the "healthy fitness zone" for all measures. Male athletes at both age groups (11-14, 15-19; p < 0.001) and female athletes aged 11-14 (p < 0.05) demonstrated lower cardiorespiratory endurance compared with Canadian general population. Female athletes (both age groups) demonstrated greater muscular strength, and male athletes (age, 15-19 years) demonstrated lower BMI than the Canadian general population. The results are concerning as male athletes demonstrated poorer HRF compared with the general population. Although most female athletes were within healthy ranges, a portion of them were still at risk. Considering the demands sport places on the body, evaluating HRF is paramount for performance and injury prevention but more importantly for overall health. Youth sport and strength coaches should evaluate and aim to enhance HRF, as participation in sport does not guarantee adequate HRF. Promoting long-term athletic development and life-long health should be a priority in youth.

Birth weight and breastfeeding are differentially associated with physical fitness components

BACKGROUND/OBJECTIVES

The study purpose was to assess the impact of birth weight and breastfeeding duration on physical fitness components.

SUBJECTS/METHODS

Study participants were 985 adolescents boys and 1246 girls (12.5-17.5 years) participating in the HELENA study. Standardised physical fitness procedures included: cardio-respiratory fitness, flexibility, upper body muscular strength, and lower body explosive strength. Birth weight and breastfeeding duration were assessed by parents' questionnaire. Associations between neonatal data and physical fitness were investigated using linear mixed models.

RESULTS

Significant associations between body muscular strength, and breastfeeding duration were observed in the unadjusted analyses for boys. When adjusting for potential confounding factors (z-score body mass index, fat-free mass, fat mass), only lower body muscular strength, by standing broad jump-a proxy measure of muscular explosivity- was positively associated with breastfeeding duration. Furthermore, significant associations were observed between upper body muscular strength (by hand grip),-a proxy measure of muscular power-in boys as well as in girls.

CONCLUSIONS

Birth weight and breastfeeding duration have different effects on muscular strength components. The present results suggest that birth weight positively influences the development of muscular power, while breastfeeding duration positively influences muscular explosivity.

Physical fitness reference standards in Italian children

Physical fitness in childhood is considered a marker of current and future health. For this reason, there is a need for a simple but reliable test to assess the different components of physical fitness even at school during physical education lessons. However, standard values are required to correctly interpret the results of such tests. Hence, this study aimed to generate sex- and age-specific normative percentile values for health-related physical fitness in Italian children. To this aim, 30,472 children aged 6-11 years from the Friuli Venezia-Giulia region (Italy) were examined. The fitness test battery included the Léger test (cardiorespiratory), the shuttle test (agility), standing long jumps, frontal throws of a basketball (lower and upper limb strength), the sit-and-reach test (flexibility), and the standing balance test. Sex- and age-percentile curves were determined using the General Additive Model for Location Scale and Shape (GAMLSS).Conclusion: The reference standards are provided as 1st, 3rd, 10th, 25th, 50th, 75th, 90th, 97th, and 99th percentiles in the form of both tables and charts and are roughly comparable with those of other European children. What is Known: • Physical fitness in childhood is considered a marker of current and future health; • Several tests have been developed to assess physical fitness in children; • There are general European reference standards for a series of tests of the main fitness components for children. What is New: • The present study provides specific reference standards for a series of tests that are indicative of the main fitness components and easily applied in children, particularly those in the Italian population; • Standing balance test and basketball frontal throw test references in a wide sample of children; • The performance of children in the present study was roughly comparable to that of other European children.

Regulation data for the horizontal jump of children and adolescents

The Horizontal Jump (HJ) is a daily tool that could be used to categorize the level of muscle fitness performance of the lower limbs. The goal was to compare the muscle fitness with those of international studies and to propose percentiles to assess the HJ performance of children and adolescents. A cross-sectional study was conducted. A total number of 3023 children and adolescents between the ages of 6.0 to 17.9 were studied. Weight, height, waist circumference (WC), and lower limb muscle fitness were evaluated. The student HJ performance values in Chile were inferior when compared to HJ performance in Brazil, Poland and Europe. For the Greek study, differences occurred only from age 6 to 15 years old. In comparison to Colombia, students showed better muscle fitness performance. These differences appeared in childhood and lasted until the beginning of adolescence. Percentiles were created to assess the lower limb fitness being an easy tool to be used and applied to classify lower limb strength.

Longitudinal Locomotor Competence and Body Mass Index Across Self-Reported Gender and Vision Level for Youth With Visual Impairments: A 3-Year Investigation

Youth with visual impairments are more likely to be overweight than peers without visual impairments and often struggle with their locomotor skills. Locomotor development can combat unhealthy body weight statuses by supporting physical activity behaviors. There are no longitudinal investigations concerning the locomotor skill and body mass index (BMI) developmental trajectories of youth with visual impairments. The purpose of this study was to examine the 3-year developmental trajectory of the locomotor skills and BMI of youth with visual impairments including differential effects of self-reported gender and degree of vision. Participants (N = 34, Mage = 11.75 years, 47% female) showed severely delayed and arrested locomotor development with increases in BMI across 3 years regardless of self-reported gender or degree of vision. Participants failed to breech a proficiency barrier of motor competence to combat against increases in BMI across time. Additional longitudinal inquiries are needed.

The Seneb's Enigma: Impact of a Hybrid Personal and Social Responsibility and Gamification Model-Based Practice on Motivation and Healthy Habits in Physical Education

Increasing physical activity (PA) and personal and social values are two of the greatest demands in the current educational system. This study examined the effects of a program based on the hybridization of the Personal and Social Responsibility Model and gamification. A total of 58 students (13.89 years old, SD = 1.14) in two groups (experimental and control) participated during a complete academic year. Motivation, physical activity and sedentary behavior were assessed through questionnaires. Physical fitness was evaluated using previously validated field tests. The results showed significant differences over time between the experimental group (EG) and control group (CG) in afterschool physical activity (APA) during the weekend (p = 0.003), sedentary time (p = 0.04) and speed–agility (p = 0.04). There were no significant differences in motivation. In reference to the intervention, the speed–agility (p = 0.000), strength (p = 0.000), agility (p = 0.000), cardiorespiratory fitness (p = 0.001), APA–weekend (p = 0.000), APA–week (p = 0.000) and sedentary time (p = 0.000) increased significantly in the EG. The speed–agility (p = 0.000), APA–weekend (p = 0.03) and sedentary time (p = 0.008) increased in the CG. The implementation of a program based on the hybridization of pedagogical models can be useful in producing improvements in physical fitness, physical activity and sedentary behaviors.

Percentiles and Principal Component Analysis of Physical Fitness From a Big Sample of Children and Adolescents Aged 6-18 Years: The DAFIS Project

Assessing physical fitness has emerged as a proxy of the health status of children and adolescents and therefore as relevant from a public health point of view. DAFIS is a project included in Plan Galicia Saudable (Healthy Galicia Plan) of the regional government of Galicia (Spain). DAFIS consists of an on-line software devoted to record the results of a standard physical fitness protocol carried out as a part of the physical education curriculum. The aims of this study were: to obtain normative values of physical fitness of the Galician school population evaluated in the DAFIS project, and to identify a reduced number of components and tests able to capture a significant amount of the variability in the physical fitness of children and adolescents. From an initial sample of 27784 records, 15287 cases (7543 males, 7744 females) were considered after filtering. Generalized Additive Models for Location, Scale and Shape were used for obtaining percentile curves and tables for each sex. Furthermore, a principal components analysis was performed, selecting the number of components by applying the Kaiser's rule and selecting a subset of variables considering the correlation between each variable and the components. Percentile curves and normative values are reported for each test and sex. Physical fitness was better in boys than in girls throughout age groups, except for flexibility that was consistently higher in girls. Two main components were detected throughout age groups: the first one representing body composition and partially cardiorespiratory fitness and the second one muscular fitness. For boys and girls, waist to height ratio had the highest correlations with the first component in four out of six age groups. The highest correlation with the second component, was most frequently observed for the handgrip test both in boys and girls (four out of six age groups). This study provides evidence about the utility of school community actions like DAFIS aimed to track the health-related fitness of children and adolescents. The results suggest that fat mass distribution (i.e., waist to height ratio and waist circumference) and muscular performance (mainly handgrip) concentrate a high proportion physical fitness variance.

Effects of an Educational Hybrid Physical Education Program on Physical Fitness, Body Composition and Sedentary and Physical Activity Times in Adolescents: The Seneb's Enigma

Physical activity (PA), body composition and sedentary behavior may affect the health of children. Therefore, this study examined the effect of an educational hybrid physical education (PE) program on physical fitness (PF), body composition and sedentary and PA times in adolescents. A 9-month group-randomized controlled trial was conducted in 150 participants (age: 14.63 ± 1.38 years) allocated into the control group (CG, n = 37) and experimental group (EG, n = 113). Cardiorespiratory fitness, speed, strength, agility, flexibility and body mass index (BMI) were assessed through previously validated field tests. Sedentary time, PA at school and afterschool were evaluated with the Youth Activity Profile-Spain questionnaire. Significant differences were observed concerning to the CG in APA-weekend (p = 0.044), speed-agility (p = 0.005) and agility (p = 0.008). Regarding the intervention, cardiorespiratory fitness (p = 0.000), speed-agility (p = 0.000), strength (p = 0.000), flexibility (p = 0.000), agility (p = 0.000), PA in school (p = 0.011), APA-weekday (p = 0.001), APA-weekend (p = 0.000), APA-week (p = 0.000), and sedentary time (p = 0.000) increased significantly in the EG. The use of a hybrid program based on teaching personal and social responsibility and gamification strategies produced enhancements in cardiorespiratory fitness, agility, speed, APA-weekdays and APA-weekends, reducing the sedentary time.

Self-Perceptions, Parents’ Perceptions, Metaperceptions, and Locomotor Skills in Adolescents With Visual Impairments: A Preliminary Investigation

Individuals with visual impairments (VI) trend toward lower motor competence when compared with peers without VI. Various forms of perception often affects motor competence. Thus, it is important to explore factors that influence forms of perception and their differential effects on motor competence for those with VI. Therefore, the purposes of this study were to explore and describe the differential effects of age, gender, and degree of vision on self-perceptions, parents’ perceptions, metaperceptions, and locomotor skills, and to examine potential associations among all variables with actual locomotor competence for adolescents with VI. Adolescents with VI completed two questionnaires and the Test of Gross Motor Development-Third Edition. Parents completed a parent perception questionnaire. Mann–Whitney U and Kruskal–Wallis H analyses showed no differential effects for gender or age on any dependent measures. Degree of vision affected locomotor skills, but not any other factor. Spearman rho correlations showed significant associations among locomotor and self-perceptions, degree of vision and locomotor, and metaperceptions with parents’ perceptions. Adolescents reported relatively high self-perceptions and metaperceptions; however, their actual locomotor competence and parents’ perceptions were relatively low. Findings may help situate future intervention strategies targeting parents supporting their children’s locomotor skills through self-perceptions.

Exploring the relationships between fundamental movement skills and health related fitness components in children

This study examined the relationship between fundamental movement skills (FMS) and health related fitness (HRF) components in children. A cross section of Irish primary school children across all age groups participated in this study (n=2098, 47% girls, age 5-12 years of age, mean age 9.2 ± 2.04). FMS were measured using the Test of Gross Motor Development (TGMD-3), along with two additional assessments of vertical jump and balance. All HRF components were also assessed: body composition through BMI and waist circumference, muscular strength (MS) using a hand dynamometer, muscular endurance (ME) through the plank test, flexibility with back-saver sit-and-reach, and cardiovascular endurance (CVE) using the 20 m PACER test. Hierarchal multiple regressions were used to measure associations between the HRF components and overall FMS and the FMS subtests: locomotor, object control and balance skills. Results show significant positive relationships between FMS and MS (R² = 0.25, β= -0.19), ME (R² = 0.11, β = 0.34), flexibility (R² = 0.13, β = 0.14) and CVE (R² = 0.17, β = 0.39), and an inverse relationship between FMS and body composition (R² = 0.25, β= -0.19). The data presented reinforces the position that the relationship between FMS and HRF is dynamic, and predominantly strengthens with age through the course of childhood. Findings suggest that developing FMS as a child may be important to developing HRF across childhood and into adolescence.

Secular changes in the anthropometric and motor characteristics of Polish male university students between 2000 and 2018

Objectives

To determine changes in the anthropometric and motor characteristics of young males during the first 20 years of the 21st century in Poland.

Materials and Methods

The study was conducted in 2000–2018 on 2691 randomly selected male university students aged 19÷25 (20.0 ± 1.1 years). The participants' body mass and height were measured, and the students participated in 13 motor ability tests. The analyzed traits were evaluated by testing the fit of linear and curvilinear functions to empirical data.

Results

The students evaluated in 2018 were 1.7 cm taller than their peers tested in 2000. Body mass and BMI values continued to decrease between 2000 and 2006 (by 0.46 kg and 0.15 kg/m² per year on average), whereas a steady and significant increase in both parameters was observed between 2006 and 2018 (by 0.45 kg and 0.12 kg/m² per year on average). The results of motor tests were strongly correlated with body mass and BMI, and they continued to improve until 2006, after which a steady decline was observed up to 2018 when the students scored lowest in motor tests.

Conclusions

The trend of increasing body height has been maintained in the studied population, but unlike body mass and BMI, the rate of increase in body height was lower than in the preceding years. A decrease in body mass and BMI is correlated with an improvement in motor tests, whereas an increase in the above parameters leads to a significant decline in all evaluated motor abilities.

Objectively measured sedentary behaviour in overweight and obese prepubertal children: challenging the school

Sedentary lifestyle is associated with unfavourable health outcomes; however, few studies have analysed the daily fluctuations of sedentary behaviour in children. The aim was to characterise sedentary behaviour in low active, overweight/obese prepubertal children and to examine whether there were daily, age- or gender-based differences. In this observational study free-living movement was measured by accelerometry for one week. Eighty-eight low active, overweight/obese children (8- to 12-year-olds) were included. Analysis was conducted for weekends, weekdays, school time and non-school time on weekdays. Participants spent half of their waking hours engaged in sedentary behaviour (48.1%). Short sedentary bouts (1-4 min) accounted for 86% of sedentary time. Sedentary time was similar on weekends and non-school time, while it was highest during school time. Interventions for the management of childhood obesity should include strategies for shifting sedentary time to physical activity on weekends and non-school time and implementing more activity-permissive classroom lessons.

Nine Months of a Structured Multisport Program Improve Physical Fitness in Preschool Children: A Quasi-Experimental Study

Research in preschool children that investigates the impact of different exercise interventions on physical fitness is limited. This pre-post study was aimed at determining if participation in a nine-month structured multisport program (MSG; n = 38) could enhance physical fitness components compared to a formal exercise program (control group (CG); n = 36) among preschool children. Physical fitness was assessed using standardized tests (the standing long jump, sit and reach, 20 m sprint, sit-ups for 30 s, bent-arm hang, medicine ball throw (MBT), grip strength, 4 × 10 m shuttle run, and 20 m shuttle run tests). The structured multisport program involved fundamental/gross and fine motor skills and ball game-based exercises twice a week. The control group was free of any programmed exercise except for the obligatory program in kindergartens. A mixed ANOVA demonstrated significant group-by-time interaction effects for the 4 × 10 m shuttle run, standing long jump, sit-ups, bent-arm hang, grip strength, and sit and reach tests (p < 0.05). There was no significant group-by-time interaction effect for the 20 m sprint test (p = 0.794) or for the 20 m shuttle run test (p = 0.549). Moreover, the MSG and CG performance in the MBT and 20 m shuttle run tests improved to a similar extent from pre- to post-test. Our results indicate that compared to the formal plan, the structured multisport program led to a sustained improvement in physical fitness in healthy 5-to-6-year old children.

Validity, Reliability, and Usefulness of My Jump 2 App for Measuring Vertical Jump in Primary School Children

There is a persistent need in sport science for developing a measuring tool that is affordable, portable, and easy to use. We aimed to examine the concurrent validity and test-retest reliability of the My Jump 2 app compared to a validated OptoJump instrument for measuring jump performance during the squat jump (SJ), countermovement jump (CMJ), and CMJ free arms (CMJAM) in primary school children. A total of 48 participants (11-14 years age), volunteered to participate in this research. The jumps were recorded with a validated OptoJump photoelectric cell system and a concurrent device (iPhone X through My Jump 2 app) at the same time. The participants repeated the testing procedure after two weeks to assess the reliability of the measurements (ICC). Systematic bias between sessions and tools was evaluated using the paired samples t-test and Bland and Altman analysis. High test-retest reliability (ICC > 0.89) was observed for all measures' in-between conditions. Very large correlations in the total sample were observed between the My Jump 2 app and OptoJump for SJ (r = 0.97, p = 0.001), CMJ (r = 0.97, p = 0.001), and CMJAM (r = 0.99, p = 0.001). Bland and Altman's plot depicting limits of agreement for the total sample between the OptoJump and My Jump 2 show that the majority of data points are within the 95% CIs. The results of this study suggest that My Jump 2 is a valid, reliable, and useful tool for measuring jump performance in primary school children.

Socioeconomic Determinants of the Anthropometric Characteristics and Motor Abilities of Polish Male University Students: A Cross-Sectional Study Conducted in 2000-2018

Aim: The aim of this study was to determine the relationships between socioeconomic factors, anthropometric characteristics and motor abilities of male university students. Materials and Methods: The study was conducted from 2000 to 2018 on 2691 male university students aged 19.98 ± 1.05 years, who were randomly selected from students attending obligatory physical education (PE) classes. The participants’ body mass and height were measured, and students participated in 13 motor ability tests that assessed their speed/agility, flexibility, strength and endurance abilities. Multiple independent samples were compared with the Kruskal–Wallis test or the mean-ranks post-hoc test when significant differences were observed in the participants’ motor abilities. Results: Factors such as the place of permanent residence, students’ monthly budget, and mother’s and father’s educational background, significantly (p < 0.05) influenced the body mass, BMI and motor abilities of first-year university students. The participants’ motor abilities (speed/agility, flexibility—partly, strength, strength endurance, and endurance) were most frequently and most significantly determined by their monthly budgets, and were least frequently and least significantly determined by their place of permanent residence. Conclusions: The students’ body height, BMI and motor abilities generally increased with a rise in population in the place of permanent residence, monthly budget, and the parents’ educational attainment.

[Lifestyle and physical condition factors associated with gender-specific BMI in Spanish preadolescents]

Introduction

Obesity has become one of the most serious health problems in our society and is associated with a multitude of conditions and complications at puberty. Through this descriptive, cross-sectional study we intended, first, to know the differences by gender in lifestyle and physical condition variables, and second, to know the determinants related to lifestyle and physical condition for a Spanish population aged 10 to 12 years with a medium socioeconomic status. The variables analyzed were BMI, physical condition variables (agility, flexibility, and cardiorespiratory capacity), and health habit variables (quality and frequency of food, physical activity, sedentary lifestyle, and sleep duration). We found significant differences between girls and boys in food quality and frequency, physical activity, sedentary lifestyle, flexibility, and maximum oxygen consumption variables. In the predictive analysis, the models significantly predicted the BMI for the total sample, the group of boys, and the group of girls. Explanatory variables include quality of breakfast, sedentary lifestyle, VO2 max and agility.

Test-Retest Reliability of Student-Administered Health-Related Fitness Tests in School Settings

PURPOSE

To examine the test-retest reliability of student-administered (SA) health-related fitness tests in school settings and to compare indices of reliability with those taken by trained research-assistants.

METHODS

Participants (n = 86; age: 13.43 [0.33] y) were divided into 2 groups, SA (n = 45, girls = 26) or research-assistant administered (RA; n = 41, girls = 21). The SA group had their measures taken by 8 students (age: 15.59 [0.56] y, girls = 4), and the RA group had their measures taken by 8 research-assistants (age: 21.21 [1.38], girls = 5). Tests were administered twice by both groups, 1 week apart. Tests included body mass index, handgrip strength, standing broad jump, isometric plank hold, 90° push-up, 4 × 10-m shuttle run, back-saver sit and reach, and blood pressure.

RESULTS

Intraclass correlation coefficients for SA (≥.797) and RA (≥.866) groups were high, and the observed systematic error (Bland-Altman plot) between test 1 and test 2 was close to 0 for all tests. The coefficient of variation was less than 10% for all tests in the SA group, aside from the 90° push-up (24.3%). The SA group had a marginally lower combined mean coefficient of variation across all tests (6.5%) in comparison with the RA group (6.8%).

CONCLUSION

This study demonstrates that, following familiarization training, SA health-related fitness tests in school-based physical education programs can be considered reliable.

A Review of Countermovement and Squat Jump Testing Methods in the Context of Public Health Examination in Adolescence: Reliability and Feasibility of Current Testing Procedures

BACKGROUND

In the context of a public health physical fitness (PF) examination in adolescence, a countermovement jump (CMJ) and a squat jump (SJ) are two vertical jump (VJ) tests widely used to evaluate lower limb muscle strength and power, respectively. The main criticism of both the CMJ and SJ test is the lack of test standardization. Therefore, the objectives of this review are: (a) to gather information about both jumps; (b) to investigate whether it is possible to identify common procedures referred to in the CMJ and SJ technical execution, and (c) to design standard operating procedures (SOPs) to promote CMJ and SJ standardization in an adolescent population aged 12-18 years.

METHODS

The review partially adopted the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (PRISMA). Due to growing attention in monitoring physical health through field tests in recent years, articles were collected using the PubMed, Web of Science, and Scopus databases from January 2009 to July 2019. Original articles in which CMJ or SJ were used to assess the muscular strength in adolescents were eligible for further analysis. Articles written in English was imposed as a limit.

RESULTS

A total of 117 studies met the inclusion criteria. The description of the CMJ and SJ test procedures was different within the literature, with discrepancies in the jump technique, number of jumps, and measurement devices used.

CONCLUSIONS

A lack of method standardization for both the CMJ and the SJ test was identified. Based on the literature, SOPs for both VJs were proposed. These are useful in the context of public health PF examination in adolescents, as they facilitate an unbiased comparison of jump performance data between published studies.

Contribution of Organized Sport Participation to Health-Related Fitness in Adolescents

The purpose of this study was to investigate the relationship between organized sport (OS) participation and health-related fitness (HRF) in adolescents. A total of 320 adolescents (176 boys) aged between 10 and 16 years reported their engagement in OS and were assessed on 5 components of HRF (cardiovascular endurance, push-ups, curl-ups, flexibility, and body mass index). Data on OS participation frequency and duration were collected through a self-reported questionnaire. Adolescents were stratified by OS participation (engaged, n = 113; nonengaged, n = 220; 55% boys). Nonparametric quantile regression models were used to estimate the differences in HRF by participation group. Less than 30% of the participants reported they were regularly engaged in OS. Frequency of participation ranged from 2 to 5 days per week (median = 2; SD = 3), and duration of participation ranged from 45 to 180 minutes per week (median = 81.7; SD = 32.4). Adolescents who participated in OS displayed better cardiovascular endurance (+4.1 laps completed), with no statistically significant difference detected on any other HRF component. Our results highlight engagement in OS as a promising strategy for achieving cardiovascular endurance. Engagement in OS alone does not seem to be sufficient to enhance fitness components other than cardiovascular endurance.

Normal weight obesity and physical fitness in Chinese university students: an overlooked association

BACKGROUND

The primary aim of this study was to examine the associations of normal weight obesity (NWO) with physical fitness in Chinese university students. As a secondary aim, we assessed whether possible differences in physical fitness between students classified as NWO and normal weight non-obese (NWNO) were mediated by skeletal muscles mass.

METHODS

A total of 383 students (205 males and 178 females, aged 18-24 years) from two universities volunteered to participate in this study. Body height and weight were measured by standard procedures and body composition was assessed by bio-impedance analysis (InBody 720). NWO was defined by a BMI of 18.5-23.9 kg/m2 and a body fat percentage of > 20% or > 30% in male and female students, respectively. Physical fitness was measured using a 10-min intermittent endurance running test (Andersen test), countermovement jumps (CMJ) and a 5 × 5 m shuttle run test (5mSR). The level of leisure time physical activity (PA) was assessed by a questionnaire.

RESULTS

13.7% of male and 27.5% of female students were classified as NWO. Compared to NWNO, students classified as NWO showed a significantly poorer performance in the Andersen test (males: 1146 ± 70 m vs. 1046 ± 95 m, females: 968 ± 61 m vs. 907 ± 67 m, p < 0.001), CMJ (males: 55.0 ± 7.6 cm vs. 44.9 ± 7.5 cm, females: 39.8 ± 8.0 cm vs. 33.7 ± 5.9 cm, p < 0.001) and 5mSR (males: 18.7 ± 1.0 s vs. 20.0 ± 0.9 s, females: 21.1 ± 1.1 s vs. 22.4 ± 1.3 s, p < 0.001), respectively. The lower levels of physical fitness in NWO were partially explained by lower skeletal muscle mass (p < 0.001) both in male and female students.

CONCLUSIONS

NWO was associated with poorer physical fitness and the relationship was partially mediated by lower skeletal muscle mass. The study indicated that attention should be paid for the potential hidden health risk in university students with normal body mass index but excessive fat mass.

Effect of a Suspension-Trainer-Based Movement Program on Measures of Fitness and Functional Movement in Children: A Pilot Study

PURPOSE

The purpose of this pilot study was to assess the efficacy of a suspension-training movement program to improve muscular- and skill-related fitness and functional movement in children, compared with controls.

METHODS

In total, 28 children [male: 46%; age: 9.3 (1.5) y; body mass index percentile: 68.6 (27.5)] were randomly assigned to intervention (n = 17) or control (n = 11) groups. The intervention group participated in a 6-week suspension-training movement program for two 1-hour sessions per week. Muscular- and skill-related fitness and functional movement assessments were measured at baseline and following the intervention. Analyses of covariance models were used to assess the effects of time and intervention.

RESULTS

The intervention participants achieved greater improvements in Modified Pull-Up performance (P = .01, Cohen's d = 0.54) and Functional Movement Screen score (P < .001, Cohen's d = 1.89), relative to controls.

CONCLUSION

The suspension-training intervention delivered twice a week was beneficial for upper body pulling muscular endurance and the Functional Movement Screen score. Future interventions using this modality in youth would benefit from larger, more diverse samples (through schools or community fitness centers) and a longer intervention length.

Effect of a pilot multi-component intervention on motor performance and metabolic risks in overweight/obese youth

This study evaluated the effect of a multi-component intervention on motor performance (MP) and metabolic risk markers (MRM) in overweight/obese youth. A secondary aim was to examine whether changes in MP are associated to changes in MRM. A 3-month multi-component intervention was performed, consisting of physical exercise sessions (twice/week;1h), nutritional education sessions (once/month), and parental support (twice/week). The sample included 35 volunteers (7-13 y.o), allocated to intervention (INT, n = 17) and control (CONT, n = 18) group. Variables were measured pre (T0) and post intervention (T1). Fasting blood samples were analyzed for MRM. MP tests included the measurement of health related physical fitness components and motor coordination performance (KTK battery). To assess food intake, a 24-hour recall diary was used. GLM-ANCOVA was performed. Standardized scores were calculated for the outcome variables, and multilinear regressions were applied to analyze associations between the key variables. INT group showed improvements in MP, glycolytic and hepatic profiles. After adjustments for MVPA, SB, total intake and maturational stage, negative associations between %ΔMP and %Δglycolytic (β = -.424; 95%CI:-0.343:-0.022), and %Δhepatic scores (β = -.382 95%CI:-0.001:-0.009) were observed. The intervention produced a moderate-to-high effect on the MP and some MRM. Changes in MP were inversely associated with changes in glycolytic and hepatic markers.

A Novel Physical Activity and Sedentary Behavior Classification and Its Relationship With Physical Fitness in Spanish Older Adults: The PHYSMED Study

BACKGROUND

As there is no gold-standard methodology to classify older people in relation to physical activity (PA) and sedentary behavior (SB), this paper aimed to propose a classification combining PA and SB.

METHODS

Within a broader study, 433 subjects, aged 55 years and older (57% females) from Madrid and Majorca, were evaluated for PA and SB by means of validated questionnaires. Physical fitness was analyzed objectively using the EXERNET test battery. Cluster analyses were used to establish behavioral patterns, combining PA and SB.

RESULTS

Males spent more time doing regular PA but less time walking and working at home than females (P < .001). Comparing the groups (inactive and high sedentary, inactive and low sedentary, active and high sedentary, and active and low sedentary), the worst aerobic endurance (P < .001) and lower body strength (P < .05) were obtained in males from both inactive groups. Agility was highest in the active and low sedentary group (P < .05). No significant differences were observed in females.

CONCLUSIONS

The proposed classification is valid, as it classifies subjects according to their PA and SB, and outcomes are related to objectively measured fitness. It could facilitate the work of public health authorities, researchers, and physicians.

Acute Effects of Block Jumps in Female Volleyball Players: The Role of Performance Level

Although the role of jumping ability in female volleyball players is well recognised, the effect of fatigue on this ability is not well known. The aim of the present study was to examine the effect of a series of block jumps (BJ) on jumping ability and whether it varies by performance level. Ten elite (EG) and 11 amateur (AG) female volleyball players performed a fatigue intervention consisting of 45 BJ, being tested for squat jump (SJ), countermovement jump (CMJ) and BJ before and after the intervention. Elasticity index (EI): (100 × (CMJ − SJ)/SJ) and upper limbs coordination index (ULCI): (100 × (BJ − CMJ)/CMJ) were calculated. After the intervention, EG showed a decrease of 4.40% in BJ height (p = 0.04; ES = 0.40), whereas AG presented an increase of 1.27%, which was not significant (p = 0.57; ES = 0.07). However, EG and AG presented no significant differences in SJ (p = 0.965 and p = 0.655) and CMJ (p = 0.742 and p = 0.211) when comparing baseline with post-intervention. Although EI and ULCI showed no significant differences after intervention in any group (AG: p = 0.989 and p = 0.114; EG: p = 0.242 and p = 0.205, respectively), AG presented a medium effect size (ES = 0.50) in EI and a small one in ULCI (ES = 0.37), also EG showed a medium-large effect in ULCI (ES = 0.75). These findings suggest that EG performance in BJ tends to decrease at the end of a specific jump training practice. Therefore, coaches and fitness trainers working with elite volleyball players should focus on exercises to maintain jumping ability during a match.

A Review of the Promotion of Fitness Measures and Health Outcomes in Youth

The relationship between physical fitness and health in adults is well established, yet until recently, empirical support for the impact of physical fitness levels on health markers in children has not been thoroughly documented. The aim of this review was to provide a summary of current literature that has examined the linkage between measures of health-related physical fitness (ie, cardiorespiratory fitness, musculoskeletal fitness, flexibility, and body composition) and health markers in youth. Specifically, this review focused on the findings from the recent 2012 Institutes of Medicine report on Fitness Measures in Youth as well as other subsequent review articles related to the topic. In addition, recommendations for health-related fitness assessments in youth populations are presented.

Reliability of Sargent Jump Test in 4- to 5-Year-Old Children

We assessed the test-retest reliability of the Sargent jump (VJ) for vertical jumping performed by 4 and 5 years old pre-schoolers. The VJ was administered three times (familiarization, test, and retest) to 163 children (mean age: 4.48 ± 0.5 years; 55.8% girls). The results were compared with those obtained in the standing long jump (SLJ) and in the 25 -m dash test to identify how its performance correlated with other measures of leg power. Systematic change in the mean and retest correlations with these other measures were used to help analyze VJ test-retest reliability. Additionally, Pearson correlation coefficients were used to examine the degree of association between the test and retest trials of the VJ. The VJ showed a higher correlation and agreement in the 4-year-old, compared with the 5-year old, group (r_c = 0.956 vs. 0.796; α = 0.95 vs. 0.84; ICC: 0.828; 95% CI: 0.730-0.891 vs 0.739; 95% CI: 0.589-0.834). Effect sizes were small ( d ≤ 0.285) for all the VJ tests performed. Fair to poor significant relationships were established between the VJ (test), VJ (retest), and the SLJ. No significant association was observed between the VJ and the 25 -m dash tests. Our findings suggest that the Sargent jump test is reliable when executed by 4- and 5-year-olds. The lack of a strong association with other measures of leg power should be taken into account at the time of selecting the most appropriate test to assess this strength dimension.

Physical fitness and academic performance in youth: A systematic review

Physical fitness (PF) is a construct of health- and skill-related attributes which have been associated with academic performance (AP) in youth. This study aimed to review the scientific evidence on the association among components of PF and AP in children and adolescents. A systematic review of articles using databases PubMed/Medline, ERIC, LILACS, SciELO, and Web of Science was undertaken. Cross-sectional and longitudinal studies examining the association between at least one component of PF and AP in children and adolescents, published between 1990 and June 2016, were included. Independent extraction of articles was carried out by the two authors using predefined data fields. From a total of 45 studies included, 25 report a positive association between components of PF with AP and 20 describe a single association between cardiorespiratory fitness (CRF) and AP. According to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines: 12 were classified as low, 32 as medium risk, and 1 as high risk of bias. Thirty-one studies reported a positive association between AP and CRF, six studies with muscular strength, three studies with flexibility, and seven studies reported a positive association between clustered of PF components and AP. The magnitude of the associations is weak to moderate (β = 0.10-0.42 and odds = 1.01-4.14). There is strong evidence for a positive association between CRF and cluster of PF with AP in cross-sectional studies; and evidence from longitudinal studies for a positive association between cluster of PF and AP; the relationship between muscular strength and flexibility with AP remains uncertain.

A comparison between active knee extension test and back-saver sit-and-reach test in assessing hamstring flexibility among healthy schoolchildren in India

Objective:

This study evaluated the correlation between the active knee extension test and the back-saver sit and reach test among healthy schoolchildren aged 9–13 years in India.

Method:

Five hundred and two healthy schoolchildren aged between 9–13 years were recruited from selected schools in India, and their hamstring flexibility for the right and the left leg was measured using the back-saver sit and reach test and the active knee extension test. The test protocol for the back-saver sit and reach test was taken from the FITNESSGRAM fitness test (while active knee extension test was performed according to the procedures taken from reliability studies). A Pearson's correlation coefficient was performed to identify the relationship between the two scores.

Results:

The mean (SD) of the test values were as follows: active knee extension test right leg: 29.09 (± 6.51); left leg: 29.07 (± 6.51). Back-saver sit and reach test right leg: 10.81 (± 1.79); left leg: 10.83 (± 1.70). The two showed a moderate correlation (right leg r=-.439 and left leg r=-.429, P≤.05). The active knee extension test was more sensitive to age increments, showing an overall decrease in the scores with advancing age.

Conclusion:

The active knee extension test and the back-saver sit and reach test are both tests that measure hamstring flexibility. The active knee extension test was found to be more sensitive to hamstring length changes, and should be used in the assessment of flexibility.

[Physical fitness reference tables for females in the 10 to 14 age range in Chillán (Chile)]

Objective To develop physical fitness reference tables oriented towards the health of female students in the 10 to 14 year age range, in Chillán, Chile. Method The present is a cross-sectional study. The sample is composed of 250 female students in the 10 to 14 year age range. To evaluate health-related physical fitness, the following tests were used: Body mass index (BMI), Deurengerg Formula (Body fat %), Wells and Dillon's Bench (Flexibility), Sargent Jump Test (lower limbs strength, 1 Mile Test (endurance) and the 30 Seconds Sit Up Test (focalized muscular endurance). Descriptive statistics were used to develop the reference tables. From the results, 5 categories were made: very bad, bad, regular, good, and very good. Age was used as a parameter. Results This study demonstrates the low level of fitness capacity of the group evaluated when compared to national and international references. It shows low levels of cardiorespiratory endurance, strength of lower limbs, flexibility, and focalized muscular endurance. The present study also shows that being overweight is associated with low cardiorespiratory capacity, and that there was a high prevalence of this in the sample compared to the national level of overweight and obesity in females in the 10-14 age range. Conclusion The tests applied in the present study are a reliable and simple tool for assessing the level of health-related fitness capacity. They can be applied in any educational institution, since a large or complex infrastructure for its application is not required.

Distribution of health-related physical fitness in Slovak population

Purpose of the study was to examine relationship between distribution of healthy fitness zone standards of high school students and their type of housing or area of residence. Study sample consisted of 684 students (284 boys, 400 girls) from urban and rural areas of the region Presov in the eastern part of Slovakia. Physical fitness was assessed by four tests: back-saver sit and reach, shoulder stretch, curl-ups and 90° push-ups. Differences by place of residence and types of housing were examined by correspondence analysis of two-dimensional tables with computing Chi square value at significance level p < 0.05. Urban students performed higher level of flexibility, abdominal and upper strength and endurance than rural ones. Boys and girls living in a flat reached higher level of flexibility and abdominal strength/endurance however, they performed worse in upper strength and endurance than those living in a house. Slovak adolescents seem to have a healthier profile in abdominal muscular fitness and upper body flexibility than in lower body flexibility. The relationship between distribution of healthy fitness zone standards and residence area or housing type was revealed only in lower body flexibility, upper strength and endurance of urban and rural girls.

Assessment of handgrip strength in preschool children aged 3 to 5 years

We investigated whether there is an optimal grip span for determining the maximum handgrip strength in preschool children and if it is influenced by gender, age, or hand size. A total of 292 preschool children (3-5 years; 59.2% boys) carried out the handgrip strength test with different grip spans (4.0, 4.5, 5.0, 5.5, and 6.0 cm). The hand size was also measured. We also determined the reliability of the optimal grip span in another group of children (n = 56, 57% boys) who did the test twice, with a 3-hour difference between tests. The results showed that 4.0 cm is the optimal grip span to determine the maximum handgrip strength in preschool children. This result applied to both genders, all age groups, and hand sizes. Paired t-tests showed no significant differences between test and retest. These findings may guide clinicians and researchers in selecting the optimal grip span when measuring handgrip strength in preschool children.Level IV.

Differences in Adolescent Physical Fitness: A Multivariate Approach and Meta-analysis

Physical fitness can be defined as a set of components that determine exercise ability and influence performance in sports. This study investigates the genetic and environmental influences on individual differences in explosive leg strength (vertical jump), handgrip strength, balance, and flexibility (sit-and-reach) in 227 healthy monozygotic and dizygotic twin pairs and 38 of their singleton siblings (mean age 17.2 ± 1.2). Heritability estimates were 49 % (95 % CI 35–60 %) for vertical jump, 59 % (95 % CI 46–69 %) for handgrip strength, 38 % (95 % CI 22–52 %) for balance, and 77 % (95 % CI 69–83 %) for flexibility. In addition, a meta-analysis was performed on all twin studies in children, adolescents and young adults reporting heritability estimates for these phenotypes. Fifteen studies, including results from our own study, were meta-analyzed by computing the weighted average heritability. This showed that genetic factors explained most of the variance in vertical jump (62 %; 95 % CI 47–77 %, N = 874), handgrip strength (63 %; 95 % CI 47–73 %, N = 4516) and flexibility (50 %; 95 % CI 38–61 %, N = 1130) in children and young adults. For balance this was 35 % (95 % CI 19–51 %, N = 978). Finally, multivariate modeling showed that the phenotypic correlations between the phenotypes in current study (0.07 < r < 0.27) were mostly driven by genetic factors. It is concluded that genetic factors contribute significantly to the variance in muscle strength, flexibility and balance; factors that may play a key role in the individual differences in adolescent exercise ability and sports performance.

A lower cardiorespiratory fitness is associated to an unhealthy status among children and adolescents from Bogotá, Colombia

OBJECTIVE

Several studies have shown that low cardiorespiratory fitness (CRF) is a significant independent risk factor for future cardiometabolic disease in adult life. The aim of this study was to examine the relationship between CRF and health status in children and adolescents in Bogotá, Colombia.

METHODS

A cross-sectional study was conducted in 921 children and adolescents aged 9-17 years living in the metropolitan area of the District of Bogotá, Colombia (2,480m asl). CRF was assessed with the 20m shuttle run test (Course-Navette) according to ALPHA-FITNESS and FITNESSGRAM standards. Blood pressure, waist circumference, hip circumference, body composition (body fat percentage, fat body mass, and fat-free mass by bioimpedance), skin fold calipers, body mass index, and sexual maturity (Tanner) were used as indicators of physical health.

RESULTS

After adjusting for sex, age, and sexual maturity, significant inverse relationships were seen between CRF and body mass index (r=-0.107), body fat percentage (r=-0.197), fat body mass (r=-0.159), skin fold (r=-0.246), and waist circumference (r=-0.169); P<.001. Schoolchildren with low CRF levels showed OR 6.06 (95% CI 3.98-9.24) increase in body fat by bioimpedance; OR 4.04 (95% CI 1.83-9.11) risk of overweight/obese by body mass index and OR 2.47 (95% CI 1.14-5.37) abdominal obesity due to increased waist circumference.

CONCLUSION

Approximately two thirds of participants had a CRF level suggesting future cardiovascular disease. Early identification of children and adolescents with low CRF levels will allow for implementing interventions to prevent cardiometabolic disease in adulthood.

[Factors associated with eating disorders in students of the University of Littoral Côte d'Opale]

AIMS

Our study aimed to observe the rate of eating disorders in first year public health students (allied medical and sports) of the University of the Littoral Opal Coast (ULCO) using the SCOFF-F (Sick, Control, One, stone, Fat, Food; French version) questionnaire and to compare morphological characteristics, level of physical condition, level of physical activity and sleep quality.

METHODS

Overall 642 subjects (459 women and 183 men) aged 22years (20.9±4.9years) participated in this study (Universanté-CEMHaVi). Weight, height, and fat mass were measured, and waist-to-hip ratio and body mass index (BMI) were calculated. The level of physical condition was evaluated using several physical tests: Leger and Boucher (20m) and shuttle run (4×10m), Sargent-test and handgrip strength. The SCOFF-F questionnaire followed by a clinical maintenance conducted by a professional was used to detect eating disorders. Several other questionnaires were used to evaluate the physical activity level; General Practice Assessment Questionnaire (GPAQ) and wellness. Sleep quality index was evaluated using Pittsburgh Sleep Quality Index (PSQI).

RESULTS

SCOFF-F was positive in 24.2% of women and 10.2% of men. In women, there were no significant differences between those who had a positive SCOFF-F screening and those who had a negative SCOFF-F screening regarding age, height, waist-to-hip ratio, level of physical condition measured and level of physical activity evaluated. However, significant differences were found between women who had a positive SCOFF-F screening and women who had a negative SCOFF-F screening regarding sleep quality, well-being score, BMI and fat mass. In men, significant differences were found between those who had a positive SCOFF-F screening and those who had a negative SCOFF-F screening regarding BMI and fat mass.

CONCLUSION

This study suggests that in both sexes, having a positive SCOFF-F screening is associated with higher BMI. In women, the increase in BMI and the perturbations in sleep quality and well-being score may indicate bulimia nervosa. The definition of a panel of possible factors associated with eating disorders can help in screening and early detection of eating disorders.