Multistage 20-m Shuttle Run Test Research Articles

Quantification of cardiac troponin-i in saliva of student-athletes at rest and following a multistage 20-m shuttle run test

Quantification of cardiac troponin-i in saliva of student-athletes at rest and following a multistage 20-m shuttle run test

Normative values of cardiorespiratory fitness in Croatian children and adolescents.

Although defining normative values of cardiorespiratory fitness have been the topic of many Western societies, little evidence has been provided for less developed countries like Croatia. Since cardiorespiratory fitness rapidly declines in Croatian children and adolescents, the newly established normative values would help health-related professionals and physical education teachers to detect 'talented' groups and direct them towards sport and 'risky' groups for planning special interventions. Therefore, the main purpose of the study was to determine normative reference values of cardiorespiratory fitness. A total of 1,612 children and adolescents aged 7-14 years (mean±SD; age 9.7±2.4 years; stature 151.0±17.6 cm; body mass 45.1±19.1 kg; 52.5% girls) participated in this cross-sectional study. Cardiorespiratory fitness was assessed by the Maximal multistage 20-m shuttle run test and the performance was expressed as the number of stages. Maximal oxygen uptake (VO2max) was estimated by equations. Smoothed percentile curves were calculated. Boys outperformed girls in the maximal number of levels achieved after the 20-m shuttle run test and in the VO2max values at each age category. In boys, a gradually higher level of performance between ages 11 and 14 was observed, while in girls the values started to rise after the age of 8. Our study provides one of the first sex- and age-specific normative values for cardiorespiratory fitness assessed by the 20-m shuttle run test in Croatian children and adolescents.

Relationship between respiratory muscles ultrasound parameters and running tests performance in adolescent football players. A pilot study.

Assessing the relationship between ultrasound imaging of respiratory muscles during tidal breathing and running tests (endurance and speed) in adolescent football players. Ultrasound parameters of the diaphragm and intercostal muscles (shear modulus, thickness, excursion, and velocity), speed (30-m distance), and endurance parameters (multi-stage 20-m shuttle run test) were measured in 22 male adolescent football players. The relation between ultrasound and running tests were analysed by Spearman's correlation. Diaphragm shear modulus at the end of tidal inspiration was moderately negatively (R=-0.49;p=0.2) correlated with the speed score at 10 m. The diaphragm and intercostal muscle shear modulus ratio was moderately to strongly negatively correlated with the speed score at 10 m and 30 m (about R=-0.48;p=0.03). Diaphragm excursion was positively correlated with the speed score at 5 m (R=0.46;p=0.04) and 10 m (R=0.52;p=0.02). Diaphragm velocity was moderately positively correlated with the speed score at 5 m (R=0.42;p=0.06) and 30 m (R=0.42;p=0.07). Ultrasound parameters were not significantly related to all endurance parameters (R≤0.36;p≥0.11). Ultrasound parameters of the respiratory muscles are related to speed score in adolescent football players. The current state of knowledge does not allow us to clearly define how important the respiratory muscles' ultrasound parameters can be in predicting some performance parameters in adolescent athletes.

The Multistage 20-m Shuttle Run Test for Predicting VO2Peak in 6-9-Year-Old Children: A Comparison with VO2Peak Predictive Equations.

Simple SummaryCardiorespiratory fitness is one of the main components of physical fitness. For children, a simple test that can be used to assess cardiorespiratory fitness is the multistage 20-m shuttle run test (20mSRT). Research has often used a portable gas analyzer to measure cardiorespiratory fitness in clinical and scientific settings; however, this may not be practical due to the high cost of the device. Moreover, the use of such a device with children is almost impracticable in school environments. Thus, to avoid using such a device, one possibility is to use equations for predicting peak oxygen consumption, which is recognized as one of the best indicators of aerobic fitness. In the present study, 22 equations were used to determine which predictive equations had greater agreement with VO2peak values measured by direct oximetry through performance of the 20mSRT. Furthermore, we verified if wearing and carrying a portable gas analyzer constrained the children’s performances. To accomplish these aims, 67 boys and 63 girls were included in the analysis. Our results showed that only six predictive equations correctly predicted the peak oxygen consumption. In addition, for girls, higher values of maximal speed, total laps, and total time were found when a portable gas analyzer was used. This information is helpful to strength and conditioning professionals and to schoolteachers if portable gas analyzers are unavailable or if the environment is not suitable for such assessments.This study aimed (i) to verify if using and carrying a portable gas analyzer (PGA) constrained the performance of school children on the multistage 20-m shuttle run test (20mSRT), (ii) to verify which peak oxygen consumption (VO2peak) predictive equations have greater agreement with VO2peak values measured by direct oximetry using the 20mSRT. The study participants were 130 children ((67 boys (age 7.76 ± 0.97 years) and 63 girls (age 7.59 ± 0.91 years)), who performed two randomized trials of the 20mSRT with and without a PGA. Twenty-two predictive equations predicted the VO2peak values through the performance of the test with and without a PGA. Without a PGA, lower values of maximal speed (MS), total laps (TL), and total time (TT) were found for girls than for boys with a PGA. Only six equations were considered to correctly predict VO2peak. In general, higher MS, TL, and TT values were found with the use of a PGA. The predicted VO2peak values from the 20mSRT varied significantly among the published predictive equations. Therefore, we suggest that the six equations that presented satisfactory accuracy could be practically used to examine cardiorespiratory fitness in schools and in research with large populations when direct measurement of VO2peak is not feasible.

Aerobic Capacity and Restitution Efficiency Level in Relation to the Training Experience and Weekly Training Volume of Male and Female Judo National Team Members in the Cadet Age Group (U18) during the Preparatory Period.

This study aims to analyze the relationship between the level of aerobic capacity and post-exercise restitution during the preparation period, with training experience and weekly training volume. All (12) athletes (six women; six men) participating in the training camp of the Polish national judo team in the cadet age group were tested. The Maximal Multistage 20-m Shuttle Run Test was used to investigate the level of aerobic capacity, and the Klonowicz coefficient of restitution (COR) 3 min after exercise (COR 3′) and 5 min after exercise (COR 5′) was used to determine the level of post-exercise restitution efficiency. The results showed that higher training experience significantly affected the deterioration of COR 3′ in female athletes and improved the results in the capacity test of male athletes. Female and male athletes with a higher weekly training volume had a higher HR at the end of the performance test. Considering the demonstrated correlations, special attention should be paid to matching the loads in training programs to the age of the athletes, introducing into training programs the teaching of body management during fatigue. Failing to adjust this may make participation impossible in competitions at the international level for older age groups.

Characteristics of the level of psychomotor abilities of female handball players.

BackgroundHandball is a high-intensity game, during which players run, change directions with or without the ball, interact with the opponent and make different decisions in both offensive and defensive actions. Players‘ performance may depend on a number of factors, including explosive force, power, speed and agility. Players‘ results may be significantly influenced by their, psychomotor abilities. This article presents an analysis of selected psychomotor abilities of female handball players at different level of competition.MethodsTest2Drive computer tests were used. The following four tests were used to measure psychomotor abilities: the Simple Reaction Time Test (SIRT), the Choice Reaction Time Test (CHORT), the Hand-Eye Coordination Test and the Spatial Anticipation Test (SPANT). The study covered a group of 118 female handball players (average age 19.6 ± 3.16), playing in the PGNiG Polish Women’s Superliga, the Polish 1st Handball League and 2nd the Polish 2nd Handball League, in the playing positions: goalkeepers, centre players, pivot players and wing players. The study also included analyses of the players‘ body composition and aerobic capacity through the use of the multistage 20-m shuttle run test. In addition, the players‘ psychomotor abilities were analysed depending on the level of competition and playing position.ResultsThe analysis of the reaction time and movement time showed statistically significant differences between the results obtained by the female handball players on different levels of competition. Moreover the female players from the Polish Women’s Superliga exhibited the fastest reaction times according to the SIRT, the CHORT and the SPANT. Additionally, on the basis of the linear Pearson correlation coefficient, a statistically significant relationship was determined between the players‘ psychomotor abilities (movement time in the SIRT, the CHORT and the SPANT) and elements of their body composition or aerobic capacity.ConclusionsThe analysis showed that the higher the level of competition (leagues), the shorter the female handball players‘ reaction times. The study also revealed that the players‘ body mass index and percentage of fat content reassociated with movement times, while their aerobic capacity (measured in the multistage 20-m shuttle run test) had a significant influence on their reaction times. This study shows that reaction time it’s one of ability which should be consider to develop in training of female handball players.

The Impact of the Daily Mile™ on School Pupils' Fitness, Cognition, and Wellbeing: Findings From Longer Term Participation.

BackgroundSchool based running programmes, such as The Daily Mile™, positively impact pupils’ physical health, however, there is limited evidence on psychological health. Additionally, current evidence is mostly limited to examining the acute impact. The present study examined the longer term impact of running programmes on pupil cognition, wellbeing, and fitness.MethodData from 6,908 school pupils (mean age 10.2 ± 0.7 years), who were participating in a citizen science project, was examined. Class teachers provided information about participation in school based running programmes. Participants completed computer-based tasks of inhibition, verbal and visual-spatial working memory, as well as the Children’s Feeling scale and Felt arousal scale to determine subjective wellbeing. A multistage 20-m shuttle run test was used to estimate fitness.ResultsFrom our total sample of 6,908 school pupils, 474 participants had been taking part in a running programme for <2 months (Shorter term participation); 1,004 participants had Longer Term participation (>3 months); and 5,430 did not take part in a running programme. The Longer Term participation group had higher fitness levels than both other groups and this remained significant when adjusted for age, sex and SES. Moderated regression analysis found that for the Shorter Term participation group, higher shuttle distance was associated with better visual-spatial working memory. Effect sizes were small though.ConclusionWe identified small and selective positive impact of participation in school based running programmes on fitness and cognition. While no long term benefit was identified for cognition or wellbeing, the impact on fitness and short term benefit suggest schools should consider participation.

Defining Optimal Cut-Points for Cardiorespiratory Fitness Associated With Overweight/Obesity in Children: A School-Based Study.

The main purpose of the study was to define optimal criterion-referenced cut-points for cardiorespiratory fitness (CRF) associated with overweight/obesity. In this cross-sectional study, participants were 1,612 children aged 7–14 years (mean age ± SD = 9.7 ± 2.4 years; 52.5% girls). CRF was assessed by the Maximal multistage 20-m shuttle run test, from which maximal oxygen uptake (VO2max) was estimated. Anthropometric indices included body-mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR). Receiver operating characteristic (ROC) curves were performed to determine cut-off points. In boys, the optimal cut-off points of CRF in defining overweight/obesity for BMI, WC, and WHtR were 44.6, 46.4, and 46.9 mlO2/kg/min. The areas under the curves (AUC) were 0.83 (95% CI 0.78–0.88, p < 0.001), 0.77 (95% CI 0.71–0.83, p < 0.001), and 0.90 (95% CI 0.86–0.93, p < 0.001). In girls, the optimal cut-off points were 41.0, 40.8, and 40.7 mlO2/kg/min for BMI, WC, and WHtR, with the AUCs of 0.86 (95% CI 0.82–0.90, p < 0.001), 0.83 (95% CI 0.79–0.88), and 0.88 (95% CI 0.84–0.93, p < 0.001). In conclusion, our newly developed cut-off points for CRF assessed by the Maximal multistage 20-m shuttle run test may adequately detect primary school-aged boys and girls with general and abdominal obesity.

Does the Multistage 20-m Shuttle Run Test Accurately Predict VO2max in NCAA Division I Women Collegiate Field Hockey Athletes?

Laboratory assessments of maximal oxygen uptake (VO2max) are considered the “gold standard” for ascertaining cardiovascular fitness, but they are not always practical for use in team sport settings. Therefore, the purpose of the current study was to compare the criterion assessment of VO2max on a treadmill to the progressive, multistage 20-m shuttle run test (i.e., Beep test), and to determine the predictability of 6 previously established Beep test predictive equations (i.e., Chatterjee, Flouris, Leger, Leger and Gadoury, Ramsbottom, St. Clair-Gibson). Collegiate women field hockey athletes (n = 65, mean±SD: age 19.6 ± 1.2 years; weight 64.7 ± 6.1 kg) completed criterion VO2max (mean ± SD: 46.4 ± 4.6 mL·kg−1·min−1) and Beep tests to volitional fatigue. According to Bland–Altman and Ordinary Least Products Regressions, the Ramsbottom (46.5 ± 4.2 mL·kg−1·min−1) and Flouris (46.3 ± 3.8 mL·kg−1·min−1) equations were considered valid predictions of criterion measured VO2max (46.4 ± 4.6). The Chatterjee, Leger, Leger and Gadoury, and St. Clair-Gibson equations overestimated VO2max, and are not recommended for use with women collegiate field hockey athletes. The Ramsbottom and Flouris estimates of VO2max from 20-m shuttle performances may be used in this population. For accurate estimates of VO2max, the clientele’s age, fitness level, and training history should be considered when selecting equations.

Effect of a Scalable School-Based Intervention on Cardiorespiratory Fitness in Children

Cardiorespiratory fitness is an important marker of childhood health and low fitness levels are a risk factor for disease later in life. Levels of children's fitness have declined in recent decades. Whether school-based physical activity interventions can increase fitness at the population level remains unclear. To evaluate the effect of an internet-based intervention on children's cardiorespiratory fitness across a large number of schools. In this cluster randomized clinical trial, 22 government-funded elementary schools (from 137 providing consent) including 1188 students stratified from grades 3 and 4 in New South Wales, Australia, were randomized. The other schools received the intervention but were not included in the analysis. Eleven schools received the internet-based intervention and 11 received the control intervention. Recruitment and baseline testing began in 2016 and ended in 2017. Research assistants, blinded to treatment allocation, completed follow-up outcome assessments at 12 and 24 months. Data were analyzed from July to August 2020. The internet-based intervention included standardized online learning for teachers and minimal in-person support from a project mentor (9-10 months). Multistage 20-m shuttle run test for cardiorespiratory fitness. Of 1219 participants (49% girls; mean [SD] age, 8.85 [0.71] years) from 22 schools, 1188 students provided baseline primary outcome data. At 12 months, the number of 20-m shuttle runs increased by 3.32 laps (95% CI, 2.44-4.20 laps) in the intervention schools and 2.11 laps (95% CI, 1.38-2.85 laps) in the control schools (adjusted difference = 1.20 laps; 95% CI, 0.17-2.24 laps). By 24 months, the adjusted difference was 2.22 laps (95% CI, 0.89-3.55 laps). The cost per student was AUD33 (USD26). In this study, a school-based intervention improved children's cardiorespiratory fitness when delivered in a large number of schools. The low cost and sustained effect over 24 months of the intervention suggests that it may have potential to be scaled at the population level. http://anzctr.org.au Identifier: ACTRN12616000731493.

Health-related physical fitness among adolescent school boys in Madinah city, western Saudi Arabia

This study aimed to measure health-related physical fitness components (cardiorespiratory fitness, body fat, muscle strength, flexibility) among adolescent school boys in Madinah, western Saudi Arabia. The participants comprised 36 male students who performed a maximal multistage 20-m shuttle run test to estimate maximal oxygen consumption (VO2max). Body fat percentage (BF%) was determined using the bioelectrical impedance scale; hand grip strength was measured using a hand grip dynamometer; and flexibility was determined using the sit and reach test. The results of the health-related physical fitness tests reveal that the mean (± SD) value of estimated VO2max was 41.1 ± 6.9 (ml.kg.min). The mean (± SD) values of BF%, right-hand grip strength, left-hand grip strength, and flexibility were 18.7 ± 8.6 (%), 33.3 ± 5.6 (kg), 32.8 ± 5.7 (kg), and 15.8 ± 3.9 (cm), respectively. With the exception of flexibility, we conclude that it is necessary to improve health-related physical fitness components, particularly muscle strength, among Saudi adolescent school boys in Madinah city.

Relationships among Actual Motor Competence, Perceived Motor Competence, and Health-Related Fitness in College-Aged Males.

Actual motor competence (MC), perceived motor competence (PMC), and health-related fitness (HRF) exhibit a dynamic and reciprocal relationship in child populations, but little is known about the nature of these relationships in young adulthood. The purpose of the study was to assess these relationships in a sample of college-aged males. A total of 55 participants enrolled in an undergraduate Kinesiology course completed the study. Perceived motor competence (PMC) was assessed with the Physical Self-Perception Profile questionnaire; MC was assessed using maximum throw and kick speed and maximum jump distance; HRF was assessed with a two-minute push-up test, two-minute sit-up test, and the Multistage 20-m Shuttle Run Test. Pearson’s bivariate correlations were calculated to assess relationships among PMC total score, MC scores, and HRF scores. Two separate indices were calculated to create composite total MC and total HRF scores used for subsequent analyses. Significant correlations were found between PMC total score, MC index, and HRF index. Multiple linear regressions were used for analyzing predictive measures for HRF and PMC scores. From the two regression models, significance varied among total MC scores, PMC scores, and HRF individual measures. These findings may suggest that relationships among MC, HRF, and PMC strengthen over developmental time in young adult males.

Adherence and Health-Related Outcomes of Beginner Running Programs: A 10-Week Observational Study

ABSTRACT Purpose: This study aimed to explore the determinants of adherence and assess changes in fitness and health outcomes in participants of group-based beginner running programs. Methods: Participants completed adherence diaries (n = 34) during the 10-week program, and underwent fitness and health testing (n = 20) at the program start and end. Diaries included weekly visual analogue scales of enjoyment, motivation, confidence, fatigue, satisfaction, and support along with a record of training sessions. Space was provided for free-text comments. Fitness was assessed by the multi-stage 20-m shuttle run test, and measurements were taken of resting heart rate, blood pressure, body composition, and free-living physical activity. Results: Overall adherence to the 10-week program was 53 ± 27% with injury the most common reason for missing sessions and for discontinuing training. Adherence to group sessions was positively correlated with enjoyment, motivation, confidence, satisfaction with progress, and social support. Qualitative analysis of diary entries indicated three distinct themes (self-awareness, social support, personal challenge) underlying progression through the program. Significant changes were observed after 10 weeks in distance run on the fitness test (+189 ± 133 m), body mass index (−0.54 ± 0.72 kg/m2), and percentage body fat (−1.5 ± 1.6%). Blood pressure, resting heart rate, and physical activity were unchanged. Conclusion: Engagement in beginner running programs was associated with improvements in cardiorespiratory fitness and body composition within 10 weeks. A larger and longer-term study is required to determine if these programs can lead to sustained engagement in running and additional health benefits.

Physical Performance, Body Composition and Somatotype in Colombian Judo Athletes

Background: Judo is a grappling sport that requires a combination of powerful actions (e.g., throwing techniques) and aerobic capacity. Physical performance, body composition and somatotype influences athletes' performance. Problem and aim. Analyze the physical performance, body composition and somatotype of elite Colombian judokas and compare them with athletes from other countries. In addition, to investigate the correlation between body composition and physical performance. Methods: Fifteen judoists, eight women (21±4.7 years) and seven men (20.5±3.9 years), participated in the present study. The athletes were black belt and had international and national competition experience, winning medals in the Pan-American Games, Central and South American Championships. Squat jumps (SJ) and countermovement jumps (CMJ) on a contact platform were performed to evaluate lower limbs power. The maximum oxygen uptake (VO2max) was estimated using the multistage 20-m shuttle run test. The Anthropometric measurements were taken for body fat and skeletal muscle mass estimation. Pearson correlation was performed between body composition and physical performance variables. Results: In summary, lower physical performance, and higher body fat percentages were observed in Colombian judoists compared to elite judoists. In other countries Moderate negative correlation was observed between aerobic power and body fat percentage (r=-0.67), and the endomorph characteristic (r=-0.69). In addition, the skeletal muscle mass presented a very large correlation with power from both SJ (r=0.88) and CMJ (r=0.89) (p Conclusion: Elite Colombian judokas presented lower physical performance, and higher body fat percentage than other elite judokas. The somatotype was adequate and in accordance with that reported at the elite level.

Assessment of physical fitness and its correlates in Chinese children and adolescents in Shanghai using the multistage 20-M shuttle-run test.

The aim of this study was to evaluate the effectiveness of a multistage 20-m shuttle-run test (20-m SRT) in assessing the physical fitness of Chinese children and adolescents in Shanghai. A total of 4833 children and adolescents (2437 males and 2396 females, aged 7-17 years) were enrolled in this study. Height, weight, body fat percentage, fat-free mass, BMI, and skinfold thickness were measured or calculated. The participants were randomly grouped for performing the 20-m SRT. The maximal oxygen uptake (VO2max and VO2max/kg ) was estimated from the 20-m SRT using the model of Leger et al. RESULTS: All the measured and calculated parameters (age, height, weight, body fat percentage, fat-free mass, BMI, skinfold thickness, and the results of the 20-m SRT, as well as the estimated VO2max and VO2max/kg ) had significant correlations with each other (P < .05). The multiple regression analyses indicated that (1) results of the 20-m SRT were significantly associated with age, sex, height, and fat-free mass (P < .05); (2) VO2max/kg was significantly associated with sex, age, weight, BMI, fat-free mass, and skinfold thickness (P < .001); and (3) VO2max was markedly associated with sex, age, height, weight, BMI, fat-free mass, and skinfold thickness (P < .001). There were differences between males and females in the results of multiple regression analyses. Results of the 20-m SRT and the estimated VO2max and VO2max/kg from the 20-m SRT can be used for evaluating the physical fitness of children and adolescents in Shanghai. Gender may be a factor affecting the effectiveness of the 20-m SRT.

Association between the PPARa and PPARGCA gene variations and physical performance in non-trained male adolescents.

The purpose of the research was to examine if some genetic variations are associated with some endurance, power and speed performances (multi-stage 20-m shuttle run, standing broad jump, 20m sprint test and Abalakov jump) in a group of 586 non-trained male adolescents (mean ± SD age: 13.20 ± 0.25years). Polymorphisms in PPARa and PPARGC1A implicated in physical performance traits were analyzed. DNA was extracted and the samples were genotyped for PPARa and PPARGC1A polymorphisms by a PCR based method followed by gel electrophoresis. The discrepancies in the study phenotypes among variations of the PPARa and PPARGC1A polymorphisms were analyzed by one-way analysis of covariance (ANCOVA), after age, weight and height adjustment. To examine whether the genotype and allele frequencies between adolescents with high and low performances were different, we divided them into two groups: ≥ 90th and < 90th of the percentile. The genotype and allele frequencies between adolescents with high and low performances were compared with the Chi square test. Our analysis demonstrated the effects of the PPARa and PPARGC1A polymorphisms only on [Formula: see text] (p = 0.010 and p = 0.010 respectively). Also, we observed significant differences in PPARa and PPARGC1A genotypes (p = 0.034 and p = 0.024) or allele frequencies (p = 0.031 and p = 0.001) between groups for the multi-stage 20-m shuttle run test. Findings of this research suggest that both the PPARa and PPARGC1A polymorphisms are associated with estimating endurance-related phenotype and endurance capacity in male non-athletes adolescents.

The relationship between motor competence and health-related fitness in children and adolescents.

Background and aimsIn the last twenty years, there has been increasing evidence that Motor Competence (MC) is vital for developing an active and healthy lifestyle. This study analyses the associations between motor competence and its components, with health-related fitness (HRF).MethodsA random sample of 546 children (278 males, mean = 10.77 years) divided into four age groups (7–8; 9–10; 11–12; 13–14 years old) was evaluated. A quantitative MC instrument (evaluating stability, locomotor and manipulative skills), a maximal multistage 20-m shuttle-run test and the handgrip test, height and BMI were used in the analyses. Pearson correlations and standard regression modelling were performed to explore the associations between variables.ResultsModerate to strong significant correlations (0.49 < r < 0.73) were found between MC and HRF, for both sexes, and correlation values were stable across the age groups. The MC model explained 74% of the HRF variance, with the locomotor component being the highest predictor for the entire sample (β = .302; p < .001). Gender-related differences were found when boys and girls were analysed at each age group. Locomotor MC for girls was the most consistent significant predictor of HRF across all age groups (0.47 < β < 0.65; all p≤.001). For boys, significant predictors were locomotor and manipulative MC (0.21 < β < 0.49; all p < .05) in the two younger age groups (7–8 and 9–10 years) and stability (0.50 < β < 0.54; all p≤.001) for the older two age groups (11–12 and 13–14 years).ConclusionThese results support the idea that: (1) the relationship between overall MC and HRF is strong and stable across childhood and early adolescence; (2) when accounting for the different MC components, boys and girls show different relationship patterns with HFR across age.

Link between Motor Competence and Health Related Fitness in Children and Adolescents.

This study examined motor competence (MC) behavior in 6- to 14-year-old children, and investigated the differences in health-related fitness (HRF) between high and low MC groups, according to sex and age. A sample of 564 children (288 males) participated in this study, divided into three age groups (6–8 years; 9–11 years; 12–14 years). Total MC and its three components (stability, locomotor, and manipulative) were assessed with a quantitative instrument. HRF was evaluated using a maximal multistage 20-m shuttle-run test and the handgrip test. Participants were divided into tertiles according to their MC level and high and low MC groups were analyzed. Overall, MC increased across age groups for both sexes, but boys presented better results than girls. The high MC group outperformed their low MC peers in all HRF variables, independent of their age group. Although cardiovascular fitness increased with age for both the high and low MC groups, the differences between these groups were greater in older children compared to younger children, within the study age range. The findings suggest that MC interventions should be considered as an important strategy to enhance HRF, and girls at a young age should be a priority target.

Comparison of Maximum Oxygen Intake (VO2max) In Ten and Fourteen-Year-Old Girls // Usporedba maksimalnog primitka kisika (VO2max) djevojčica dobi 10 i 14 godina

The objective of the present research was to determine whether aerobic capacity of fourteen-year-old girls is higher than that of ten-year-old girls. The research aimed to establish if the level of cardio respiratory fitness in girls decreases with age, and if their overall physical activity also decreases. A low level of cardio respiratory fitness from an early age has been confirmed in a number of studies, and it has been highly correlated with a sedentary lifestyle. Research participants were 94 fourth and eighth grade primary school girls. The variables were anthropometric measures for body height, body weight, waist circumference, and hips circumference. All the measurements were done in accordance with the International Biological Program (IBP). Body fat percentage (BF%) was also measured with the Omron (Type BF511, Japan). A multistage 20m shuttle run test was used to obtain the values for aerobic capacity, and PAQ-C questionnaire was used to estimate the level of physical activity. The results indicate that only 5% of female students meet the recommendations for physical activity while 83% engage in moderate physical activity. Statistically significant differences were determined for the variables used to estimate the aerobic capacity, with ten-year-old girls (p=0.00) having better aerobic capacity than the fourteen-year-old girls. Furthermore, ten-year-old girls were found to be significantly more physically active (p=0.00). The results of the correlation test between the aerobic capacity (VO2 max) and the overall physical activity (PA) indicate significant positive correlation (r = 0.42; p = 0.00). Girls who do not engage in physical activity at least for the recommended 60 minutes need to be directed towards various forms of healthy lifestyle with a special emphasis on everyday physical exercise that may increase their aerobic capacity.

Expression analysis of selected classes of circulating exosomal miRNAs in soccer players as an indicator of adaptation to physical activity

Recently studies have shown that, depending on the type of training and its duration, the expression levels of selected circulating myomiRNAs (c-miR-27a,b, c-miR-29a,b,c, c-miR-133a) differ and correlate with the physiological indicators of adaptation to physical activity. To analyse the expression of selected classes of miRNAs in soccer players during different periods of their training cycle. The study involved 22 soccer players aged 17-18 years. The multi-stage 20-m shuttle run test was used to estimate VO2 max among the soccer players. Samples serum were collected at baseline (time point I), after one week (time point II), and after 2 months of training (time point III). The analysis of the relative quantification (RQ) level of three exosomal myomiRNAs, c-miRNA-27b, c-miR-29a, and c-miR-133, was performed by quantitative polymerase chain reaction (qPCR) at three time points – before the training, after 1 week of training and after the completion of two months of competition season training. The expression analysis showed low expression levels (according to references) of all evaluated myomiRNAs before the training cycle. Analysis performed after a week of the training cycle and after completion of the entire training cycle showed elevated expression of all tested myomiRNAs. Statistical analysis revealed significant differences between the first and the second time point in soccer players for c-miR-27b and c-miR-29a; between the first and the third time point for c-miR-27b and c-miR-29a; and between the second and the third time point for c-miR-27b. Statistical analysis showed a positive correlation between the levels of c-miR-29a and VO2 max. Two months of training affected the expression of c-miR-27b and miR-29a in soccer players. The increased expression of c-miR-27b and c-miR-29 with training could indicate their probable role in the adaptation process that takes place in the muscular system. Possibly, the expression of c-miR-29a will be found to be involved in cardiorespiratory fitness in future research.