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1.
Little is known about the influence of different types and sources of social support on physical activity in adolescents. The aim of this study was to analyse the association between physical activity and different types and sources of social support in adolescents. The sample consisted of 2,859 adolescents between 14–19 years of age in the city of João Pessoa, in Northeastern Brazil. Physical activity was measured with a questionnaire and social support from parents and friends using a 10-item scale five for each group (type of support: encouragement, joint participation, watching, inviting, positive comments and transportation). Multivariable analysis showed that the types of support provided by parents associated with physical activity in adolescents were encouragement for females (P < 0.001) and adolescents between 14–16 years of age (P = 0.003), and transportation (P = 0.014) and comments (P = 0.037) for males. The types of social support provided by friends were: joint participation in male adolescents (P < 0.001) and in these 17–19-year-olds (P < 0.001), and comments in both genders (males: P = 0.009; females: P < 0.001) and 14–16-year-olds (P < 0.001). We conclude that the type of social support associated with physical activity varies according to its source, as well as the gender and age of the adolescents.  相似文献   

2.
Abstract

Throughout adolescence, swimmers begin to carry out demanding endurance and high-intensity training sets, the effect of which on redox status is largely unknown. The aim of the present study was to investigate the effects of 2000-m continuous swimming and 6 × 50-m maximal swimming on the redox status of adolescent swimmers. Fifteen male and 15 female swimmers, aged 14–18 years, provided blood samples before, immediately after, 1 h after, and 24 h after each exercise for the determination of redox status parameters. Oxidative damage was short-lived and manifest as increases in 8-hydroxy-2?-deoxyguanosine (8-OHdG) 1 h after high-intensity exercise (39%, P < 0.001) and in malondialdehyde immediately after both exercises (65%, P < 0.001). Alterations in antioxidant parameters were sustained during recovery: reduced glutathione decreased 24 h post-exercise (11%, P = 0.001), uric acid increased gradually after high-intensity exercise (29%, P < 0.001) and bilirubin peaked 24 h post-exercise (29%, P < 0.001). Males had higher 8-OHdG (49%, P = 0.001) and uric acid (29%, P < 0.001) concentrations than females. However, females showed higher values of malondialdehyde than males immediately post-exercise (30%, P = 0.039), despite lower pre-exercise values. In conclusion, both endurance and high-intensity exercise perturbed the redox balance without inducing prolonged oxidative damage in trained adolescent male and female swimmers. These swimming training trials were not found to be detrimental to the redox homeostasis of adolescents.  相似文献   

3.
Abstract

The main aim of this study was to develop and test psychometrically the Physical Education Predisposition Scale, to assess secondary school students' cost–benefit assessment of physical education (PE) participation (PE attitude affective and attitude cognitive) and self-perceptions (PE perceived competence and self-efficacy). Secondary aims were to explore how the two variables were related, and to investigate age and gender differences. Altogether, 315 Year 8 and 9 students (aged 12–14 years) from four North West England schools completed the Physical Education Predisposition Scale. Principal components analysis revealed the presence of a simple two-factor solution explaining 60.7% of the variance. Factor 1 (labelled Perceived PE Worth) reflected attitude affective and attitude cognitive (α = 0.91), and factor 2 (Perceived PE Ability) represented perceived competence and self-efficacy (α = 0.89). Significant positive correlations were observed between the factors (r = 0.67 to 0.71, P < 0.001). Boys scored significantly higher than girls on Perceived PE Worth (P < 0.001) and Perceived PE Ability (P = 0.02). Similarly, Year 8 students scored significantly higher than Year 9 students on Perceived PE Worth (P = 0.005) and Perceived PE Ability (P < 0.001). Our results support the potential of the Physical Education Predisposition Scale as a concise measurement tool for use in the PE setting, for both teachers and researchers.  相似文献   

4.
Abstract

There is empirical evidence that children’s physical activity is dependent on climatic conditions. In addition, a correlation between physical activity level and physical fitness has been identified. In this longitudinal study, we investigate whether seasons have an influence on physical fitness. A total of 145 German elementary school children were tested every six months over a two-year period. We used the German Motor Test 6–18 to assess physical fitness. Performance in the 6-min endurance run (P < 0.001), bidirectional jumping (P < 0.001), the standing long jump (P = 0.026), the 20 m sprint (P = 0.006) and the stand-and-reach task (P = 0.017) was significantly better in summer than in winter. There were no differences in the ability to balance backwards (P = 0.120); in the winter, the results for push-ups (P < 0.001) and sit-ups (P < 0.001) were better than those in the summer. We have shown that physical fitness is significantly influenced by the season. Consequently, when children’s fitness tests are used (e.g. as the basis for intervention programs, for classifying health-risk groups or for recognising talent), the season in which testing occurred should be reported and accounted for in future studies.  相似文献   

5.
The aim of this study was to determine if a potential relationship among physical activity (PA), fundamental movement skills and weight status exists amongst early adolescent youth. Participants were a sample of 85 students; 54 boys (mean age = 12.94 ± 0.33 years) and 31 girls (mean age = 12.75 ± 0.43 years). Data gathered during physical education class included PA (accelerometry), fundamental movement skills and anthropometric measurements. Standard multiple regression revealed that PA and total fundamental movement skill proficiency scores explained 16.5% (P < 0.001) of the variance in the prediction of body mass index. Chi-square tests for independence further indicated that compared with overweight or obese adolescents, a significantly higher proportion of adolescents classified as normal weight achieved mastery/near-mastery in fundamental movement skills. Results from the current investigation indicate that weight status is an important correlate of fundamental movement skill proficiency during adolescence. Aligned with most recent research, school- and community-based programmes that include developmentally structured learning experiences delivered by specialists can significantly improve fundamental movement skill proficiency in youth.  相似文献   

6.
This study examined fundamental movement skill (FMS) proficiency among male (N = 216) and female (N = 198) Irish primary school pupils from Year 2 to Year 7 (9.0 ± 1.7 years). Following anthropometric measurements, participants were video-recorded performing 15 FMS and scored using the TGMD-3, Victorian Fundamental Movement skills Manual and the Get skilled: Get active guidelines. Percentage mastery ranged between 1.4% (gallop) and 35.7% (slide). A two-way ANOVA evaluated the effect of sex (male/female) and class group (Year 2/3/4/5/6/7) on individual skills, locomotor subtest, object-control subtest and total TGMD-3 (GMQ) scores. No significant sex ×class interaction effects were found. Large effect sizes were reported for male superiority in object-control subtest (ηp2 = 0.26) and GMQ (ηp2 = 0.16) scores (both p < 0.001). Older classes had higher object-control subtest scores than younger classes, but scores plateaued after Year 5. Furthermore, overweight participants had significantly lower locomotor subtest (p < 0.001, d = 0.7), object-control subtest (p = 0.03, d = 0.3) and GMQ scores (p < 0.001, d = 0.5) than non-overweight participants. This study highlights very poor levels of FMS mastery among Irish schoolchildren and stresses the need for developmentally appropriate, FMS intervention programmes that are inclusive regardless of age, sex or weight status.  相似文献   

7.
Abstract

This aim of this study was to compare the new Actigraph (GT1M) with the widely used Model 7164. Seven days of free-living physical activity were measured simultaneously using both the Model 7164 and GT1M in 30 Indian adolescents (mean age 15.8 years, s = 0.6). The GT1M was on average 9% lower per epoch than model 7164, thus a correction factor of 0.91 is suggested for comparison between the two monitors. The differences between monitors increased in magnitude with intensity of activity (P < 0.001) but remained randomly distributed (r = 0.01, P = 0.96). No significant difference was observed between monitors for time spent in moderate (P = 0.31) and vigorous (P = 0.34) physical activity when using the same epoch length. The Model 7164 classified less time as sedentary (P < 0.001) and more time as light-intensity activity (P < 0.001) than the GT1M. In conclusion, data from the GT1M can be compared with historical data using average counts per minute with a correction factor, and the two models might be comparable for assessing time spent in moderate to vigorous physical activity in children when using the same epoch length.  相似文献   

8.
This study examined differences in children’s body mass index (BMI) and body fatness (BF%) as a function of gender and fundamental movement skill (FMS) proficiency. Following ethics approval and parental consent, 248, 6–11 year-old children (112 boys, 136 girls) underwent assessment of 7 FMS: sprint run, side gallop, hop, kick, catch, throw and vertical jump. FMS tertiles (“high”, “medium” or “low” FMS) were created based on the summed components of the FMS. Skinfold measures were used to calculate BF%. Physical activity (PA) was assessed using pedometry and maturation predicted using anthropometry. Data were analysed using a 2 (Gender) × 3 (FMS tertile) ways analysis of covariance (ANCOVA), controlling for age, maturation and PA. Age (P = .001) and maturation (P = .006) were associated with BMI. Girls classified as high FMS proficiency had significantly lower BMI compared to girls with low and medium FMS proficiency. Age (P = .0001) and maturation (P = .007) were associated with BF%. BF% was also higher for girls with low FMS compared to those with medium and high FMS. BF% and BMI were not different across FMS tertile in boys. Such findings suggest focusing on FMS may be especially important for healthy weight, particularly in girls.  相似文献   

9.
Purpose: This study aimed to investigate the relationship between fundamental movement skills (FMS) and markers of health among a cohort of Irish primary school children. Methods: Participants (N = 296, mean age: 7.99 ± 2.02 years) were senior infant (n = 149, mean age: 6.02 ± 0.39 years) and 4th class (n = 147, mean age: 9.97 ± 0.40 years) students from three primary schools in Cork, Ireland. FMS proficiency (TGMD-2) and markers of health (BMI percentile, waist circumference percentile, blood pressure percentiles, resting heart rate, cardiorespiratory fitness, objectively measured physical activity; PA) measurements were recorded. Correlation and hierarchical stepwise multiple linear regression analyses were conducted to investigate the relationship between FMS and markers of health. Results: A small, positive relationship was found between FMS (Gross Motor Quotient; GMQ) and cardiorespiratory fitness with small negative correlations between GMQ and 550 m time SDS among 6-year-olds (r(129) = ?.286, p < .05) and 10-year-olds (r(132) = ?.340, p < .05). A moderate, positive correlation was found between GMQ and light PA (r(71) = .400, p < .05). Small positive correlations were revealed between GMQ and moderate PA (r(71) = .259, p < .05) and between GMQ and total PA (r(71) = .355, p < .05). After adjusting for age, sex, the interaction effect of age and sex, and school attended, FMS explained 15.9% and 24.8% of the variance in 550 m time SDS among 6- and 10-year-olds, respectively, and 6% and 6.5% of the variance in light PA and moderate PA, respectively. After adjusting for age and sex, FMS explained 11.6% of the variance in total PA. Conclusion: A wide range of FMS is important for children’s cardiorespiratory fitness and PA.  相似文献   

10.
Abstract

In this study, we investigated the relationship between physiological, anthropometric, and skill qualities and playing performance in professional rugby league players. Fifty-eight high-performance rugby league players underwent measurements for anthropometry (height, body mass, sum of seven skinfolds), physiological (speed, change of direction speed, lower body muscular power, repeated-sprint ability, prolonged high-intensity intermittent running ability, and estimated maximal aerobic power), technical skill (tackling proficiency, draw and pass proficiency), and perceptual skill (reactive agility, pattern recall, pattern prediction) qualities. National Rugby League matches were coded for attacking (e.g. line breaks, try assists, etc.) and defensive (e.g. missed tackles, tackling efficiency, etc.) statistics commonly used to assess rugby league playing performance. The number of line break assists was significantly associated (P < 0.05) with greater playing experience (r = 0.36), dual-task draw and pass proficiency (r = 0.54), reactive agility (r = 0.29), and pattern recall (r = 0.32) and prediction (r = 0.28) ability, while faster speed over 40 m (r = ?0.42) was associated (P < 0.05) with a higher number of tries scored. Greater age and playing experience, better lower body muscular power, and faster 10 m and 40 m speed were significantly associated (P < 0.05) with the number of tackle attempts (positive), tackles completed (positive), and proportion of missed tackles (negative). These findings demonstrate that well-developed physical and skill qualities are associated with effective playing performance in National Rugby League players.  相似文献   

11.
Abstract

The purpose of this study was to evaluate the impact of an extra-curricular school sport programme to promote physical activity among adolescents. One hundred and sixteen students (mean age 14.2 years, s = 0.5) were assigned to an intervention (n = 50) or comparison group (n = 66). The 8-week intervention involved structured exercise activities and information sessions. Four days of pedometer monitoring and time spent in non-organized physical activity and sedentary behaviours were measured at baseline and post-test. At baseline, participants were classified using steps per day as low-active (girls <11,000, boys <13,000) or active (girls ≥ 11,000, boys ≥ 13,000) and the effects of the intervention were assessed using these subgroups. Adolescents in the intervention group classified as low-active at baseline increased their step counts across the 8-week intervention (baseline: 7716 steps/day, s = 1751; post-test: 10,301 steps/day, s = 4410; P < 0.05) and accumulated significantly more steps (P < 0.05) than their peers in the comparison group (baseline: 8414 steps/day, s = 2460; post-test: 8248 steps/day, s = 3674; P = 0.879). The results of the present study provide further evidence that physical activity monitoring using pedometers is an effective strategy for increasing activity among low-active adolescents.  相似文献   

12.
Socio-economic status during childhood has been shown to be a strong predictor of adult health outcome. Therefore, we examined associations of parental educational level, household income and migrant background with physical fitness, spinal flexibility, spinal posture as well as retinal vessel diameters in children of an urban Swiss region. A total of 358 first graders of the Swiss canton Basel-Stadt (age: 7.3, SD: 0.4) were examined. Physical fitness (20 m shuttle run test, 20 m sprint, jumping sidewards and balancing backwards), spinal flexibility and spinal posture (MediMouse®, Idiag, Fehraltdorf, Switzerland) and retinal microcirculation (Static Retinal Vessel Analyzer, Imedos Systems UG, Jena, Germany) were assessed. Parental education, household income, migrant background and activity behaviour were evaluated with a questionnaire. Parental education was associated with child aerobic fitness (P = 0.03) and screen time (P < 0.001). Household income was associated with jumping sidewards (P = 0.009), balancing backwards (P = 0.03) and sports club participation (P = 0.02). Migrant background was associated with BMI (P = 0.001), body fat (P = 0.03), aerobic fitness (P = 0.007), time spent playing outdoors (P < 0.001) and screen time (P < 0.001). For spinal flexibility and retinal vessel diameter, no associations were found (0.06 < P < 0.8). Low parental education, low household income and a migrant background are associated with poor physical fitness, higher BMI and body fat percentage and low-activity behaviour.  相似文献   

13.
Abstract

The aim of this study was to assess the extent to which measures derived from the new FIFA referees’ fitness tests can be used to monitor a referee's match-related physical capacity. Match-analysis data were collected (Prozone®, Leeds, UK) from 17 soccer referees for 5.0 (s = 1.7) FA Premier League matches per referee during the first 4 months of the 2007–08 season. Physical match performance categories included total distance covered, high-intensity running distance (speed >5.5 m · s?1), and sprinting distance (>7.0 m · s?1). The two tests were a 6 × 40-m sprint test and a 150-m interval test. Heart rate demand was correlated with total match distance covered (r = ?0.70, P = 0.002) and high-intensity running (r = ?0.57, P = 0.018) in the interval test. The fastest 40-m sprint was related to total distance covered (r = ?0.69, P = 0.002), high-intensity running (r = ?0.76, P < 0.001), and sprinting distance (r = ?0.75, P = 0.001), while mean time for the 40-m sprints was related to total distance covered (r = ?0.70, P = 0.002), high-intensity running (r = ?0.77, P < 0.001), and sprinting distance (r = ?0.77, P < 0.001). The referees who recorded the best interval-test heart rate demand and fastest 40-m time produced the best physical match performances. However, only the sprint test and in particular the fastest 40-m time had appropriate construct validity for the physical assessment of soccer referees.  相似文献   

14.
ABSTRACT

The aim of this study was to examine the relationship between the peak velocity derived from the Carminatti Test (T-CAR) (PVT-CAR) and physical match performance in young soccer players. Thirty-three youth soccer players were recruited from 2 non-professional clubs. Friendly matches and small-sided game were performed. Physical match demands were assessed using Global Positioning System (GPS) technology. On a separate occasion, the players were submitted to the T-CAR. Players were categorised into 3 groups based on their T-CAR performance: Low (PVT-CAR ≤ P33), Intermediate (P33 > PVT-CAR < P66) and High (PVT-CAR ≥ P66). The PVT-CAR (15.5 ± 0.7 km·h?1) was significantly related to high-intensity activities (HIA; r = 0.78, P < 0.001), high-intensity running (HIR; r = 0.66, P < 0.001), sprinting (r = 0.62, P < 0.001) and total distance (TD) covered (r = 0.47, P < 0.01) during friendly matches. The PVT-CAR was strongly correlated with the amount of HIA (r = 0.81, P < 0.001), HIR (r = 0.85, P < 0.001) and TD covered (r = 0.81, P < 0.001) during small-sided game. No significant correlation was observed between the PVT-CAR and distance of sprinting (r = 0.49, P = 0.067) during small-side game. Furthermore, players in the High group covered significantly more TD (10%) and did more HIA (42%), sprinting (31%) and HIR (25%) during friendly matches compared to the players classified as having Low performance on the T-CAR. These differences still remained after adjusting for chronological age (CA), maturity and body size. In conclusion, the current study gives empirical support to the ecological and construct validity of this novel field test (T-CAR) as an indicator of match-related physical performance in young soccer players during pubertal years.  相似文献   

15.
ABSTRACT

The Functional Movement Screen? (FMS?) is aimed at assessing fundamental movements and is often used to identify players’ injury risk. The purpose of this study was to determine whether the FMS? can be used to predict injuries in veteran footballers (aged > 32 years). Eighteen veteran football teams (n = 238) were recruited and prospectively followed for 9 months. The players (44 ± 7 years; 178 ± 7 cm, 84 ± 11 kg) performed the FMS? at the start of the study period. Players’ exposure hours and injuries were recorded. The difference of FMS? overall score between injured and uninjured players was not significant (11.7 ± 2.9 vs 12.2 ± 2.8 points; Mann-Whitney U-test P = 0.17). Players scoring <10 (score < 1 standard deviation [SD]) below the mean) had a significantly higher injury incidence (z-statistics P < 0.05) compared to an intermediate reference group (mean ± 1 SD; scores of 10–14). No lower injury incidence for players with scores of >14 (score > 1 SD above the mean) was found. Further analyses of potential risk factors suggest higher age, lower body mass and a longer football career to be risk factors for injuries. The findings of this study suggest that the suitability of the FMS? for injury prediction in veteran footballers is limited.  相似文献   

16.
The purpose of this investigation was to measure the interface pressure exerted by lower body sports compression garments, in order to assess the effect of garment type, size and posture in athletes. Twelve national-level boxers were fitted with sports compression garments (tights and leggings), each in three different sizes (undersized, recommended size and oversized). Interface pressure was assessed across six landmarks on the lower limb (ranging from medial malleolus to upper thigh) as athletes assumed sitting, standing and supine postures. Sports compression leggings exerted a significantly higher mean pressure than sports compression tights (P < 0.001). Oversized tights applied significantly less pressure than manufacturer-recommended size or undersized tights (P < 0.001), yet no significant differences were apparent between different-sized leggings. Standing posture resulted in significantly higher mean pressure application than a seated posture for both tights and leggings (P < 0.001 and P = 0.002, respectively). Pressure was different across landmarks, with analyses revealing a pressure profile that was neither strictly graduated nor progressive in nature. The pressure applied by sports compression garments is significantly affected by garment type, size and posture assumed by the wearer.  相似文献   

17.
Physical education (PE) teachers have a physically demanding job, putting them at a considerable risk for musculoskeletal injuries. To structurally develop tailored injury prevention programmes for PE teachers, a clear understanding of the extent, characteristics and underlying factors of their musculoskeletal injuries compared to referents is necessary. Therefore, the current study prospectively followed 103 PE teachers and 58 non-PE teachers, who registered musculoskeletal injuries and time of exposure to sports participation during one school year. Pearson χ2-tests and independent samples t-tests determined significant differences between PE and non-PE teachers regarding demographics and variables possibly related to injury occurrence. PE teachers had 1.23 and non-PE teachers 0.78 injuries/teacher/school year. This difference was significantly different after adjustment for hours spent weekly on intracurricular teaching during the career and for injury history during the preceding six months (P = 0.009; OR = 0.511; 95% CI = 0.308–0.846). PE teachers’ most affected body parts were the knee and the back. PE teachers had a more extensive injury history (P < 0.001), a higher work- (P < 0.001) and sport index (P < 0.001), practiced more sports (P < 0.002) and taught more extracurricular sports (P = 0.001). Future injury prevention programmes should take account for the great injury history and heavy physical load in PE teachers.  相似文献   

18.
This study aimed to analyse the effects of two factors (number of players and training regimes) on players’ physiological and technical demands in basketball ball-drills. Twenty-one young basketball players performed four different ball-drills (two levels for each factor). The number of players involved was 2vs2 and 4vs4, while ball-drill regimes were continuous and intermittent. Physiological demand was assessed using the percentage of maximal heart rate (%HRmax), Edwards’ training load and rating of perceived exertion (RPE). Furthermore, the following technical actions were collected: dribbles, steals, rebounds, turnovers, passes (total, correct, wrong and % of correct pass) and shots (total, scored, missed and % of made shot). A 2 × 2 (number of players × regime) two-way ANOVA with repeated measures was applied for physiological parameters and technical actions. The 2vs2 condition showed higher %HRmax (P < 0.001), Edwards’ training load (P < 0.001), RPE (P < 0.001), number of dribbles (P < 0.001), rebounds (P < 0.001), passes [total (P = 0.005) and correct (P = 0.005)] and shots [total (P < 0.001) scored (P < 0.001) and missed (P < 0.001)] than 4vs4. Moreover, the continuous regime revealed higher %HRmax (P < 0.001), Edwards’ training load (P < 0.001), RPE (P = 0.006) and dribbles (P < 0.001) than the intermittent regime. This study showed that both number of players and regime are useful variables able to modify basketball ball-drills workload.  相似文献   

19.
Abstract

The aims of the present study were (1) to analyse the physical demands of top-class referees and (2) to compare their official FIFA fitness test results with physical performance during a match. The work rate profiles of 11 international referees were assessed during 12 competitive matches at the 2003 FIFA Under-17 World Cup and then analysed using a bi-dimensional photogrammetric video analysis system based on direct lineal transformation (DLT) algorithms. In the first 15 min of matches, the referees were more active, performing more high-intensity exercise (P < 0.01) than in the first 15 min of the second half. During the second half of matches, the referees covered a shorter distance (P < 0.01), spent more time standing still (P < 0.05), and covered less ground cruising (P < 0.05), sprinting (P < 0.05), and moving backwards (P < 0.001) than in the first half. Also in the second 45 min, the distance of referees from infringements increased (P < 0.05) in the left attacking zone of the filed. There was also a decrease (P < 0.05) in performance in the period following the most high-intensity activity, compared with the mean for the 90 min. Time spent performing high-intensity activities during a match was not related to performance in the 12-min run (r 2 = 0.30; P < 0.05), the 200-m sprint (r 2 = 0.05; P < 0.05), or the 50-m sprint (r 2 = 0.001; P < 0.05). The results of this study show that: (1) top-class referees experienced fatigue at different stages of the match, and (2) the typical field tests used by FIFA (two 50-m and 200-m sprints, followed by a 12-min run) are not correlated with match activities.  相似文献   

20.
Abstract

The agreement between self-reported and objective estimates of activity energy expenditure was evaluated in adolescents by age, sex, and weight status. Altogether, 403 participants (217 females, 186 males) aged 13–16 years completed a 3-day physical activity diary and wore a GT1M accelerometer on the same days. Partial correlations (controlling for body mass) were used to determine associations between estimated activity energy expenditure (kcal · min?1) from the diary and accelerometry. Differences in the magnitude of the correlations were examined using Fisher's r to z transformations. Bland–Altman procedures were used to determine concordance between the self-reported and objective estimates. Partial correlations between assessments of activity energy expenditure (kcal · min?1) did not differ significantly by age (13–14 years: r = 0.41; 15–16 years: r = 0.42) or weight status (normal weight: r = 0.42; overweight: r = 0.39). The magnitude of the association was significantly affected by sex (Δr = 0.11; P < 0.05). The agreement was significantly higher in males than in females. The relationship between activity energy expenditure assessed by the objective method and the 3-day diary was moderate (controlling for weight, correlations ranged between 0.33 and 0.44). However, the 3-day diary revealed less agreement in specific group analyses; it markedly underestimated activity energy expenditure in overweight/obese and older adolescents. The assessment of activity energy expenditure is complex and may require a combination of methods.  相似文献   

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