Relative age effects in international age group championships: A study of Spanish track and field athletes

The relative age effect is a well-researched phenomenon, however there is still a dearth of understanding in track and field and female sport. This study investigated the role of relative age on selection for international competition of Spanish age group athletes between 2006– 2014. Six hundred and forty two athletes competed for Spain at U20 or U18 age group international competition (n = 359 males; 283 females) across 9 years. The birthdates of these athletes were compared against the population of registered athletes at that time (14,502 males; 10,096 females). The results highlighted the influential role of relative age on selection to these opportunities. In line with previous research, this effect was mediated by age and gender, with stronger effects for both males and younger athletes (U18). The data best supported the 'maturation-selection' hypothesis as a mechanism for RAEs. These results highlight the need to carefully consider the role and need for international competitive opportunities at different age groups. A number of possible context relevant solutions are discussed , including correction adjustments techniques and competition structure within track and field

Relationship between anaerobic work capacity and critical oxygenation in athletes

Objective: Anaerobic work capacity (AWC) is understood as the maximum power that the athlete can withstand over time, conditioned by high intensity effort and it is important to interpret it for the performance improvement. In addition, the muscle oxygen saturation (SmO 2) provides information on muscle metabolism and hemodynamics. Likewise, critical oxygenation (CO) is the highest metabolic rate that results in a fully oxidative energy supply that reaches a stable state at the substrate level. The main problem is that SmO2 generally offers a traditional laboratory interpretation without application in field tests, Therefore, the purpose of this study is to provide the use of CO as an indicator of AWC performance in high intensity exercise. Methods: Twenty-two male rugby players participated. Peak torques during an isokinetic fatigue test and muscle oxygen consumption (mVO 2) and SmO2 in the vastus lateralis were measured. A correlation and multiple regression analysis were applied to find an explanatory prediction model of the AWC. Results: A greater SmO2 amplitude and CO would mean less anaerobic work (r = -0.58 and r=-0.63) and less force production. In addition, CO along with weight (kg) can explain the AWC by 64% during high intensity exercise. Conclusion: The measurement of critical oxygenation is associated with the AWC, so should be considered a performance factor. These parameters could be included in NIRS sensors to evaluate muscle metabolism

Medición de la oxigenación muscular en reposo y la relación con los saltos en contramovimiento y la composición corporal en jugadores de futbol

The measurement of resting muscle oxygenation capa city is under investigation in team sports. The aim of the current study was to observe the changes after a preseason, in muscle oxygen saturation (SmO2) at rest and the relationship with body composition and jump power in soccer players. 17 soccer players (age 21.8 ± 2.2 years) were enrolled. Body composition, somatotype, countermovement jump (CMJ) and single-leg countermovement jump (SLCMJ) were evaluated. Also, SmO2 at rest in the gastrocnemius muscle using the technique of arterial occlusion in the dominant leg and non-dominant leg was performed. All measurements were made before and after the preseason. The t-student test, Pearson’s correlation and inter-individual response of the subject’s statistic were applied to measure the magnitudes of change and the effect size. An inverse relationship was observed between SmO2 at the initial-occlusion (r= -0.82), final-occlusion (r= -0.79) and SmO2 recovery (r= -0.82) with the SLCMJ power. A moderate relationship was also observed between oxygen consumption and fat mass (r= 0.64). The measurement of SmO2 at rest can be considered as a possible performance parameter because it has determined its relationship with the ability to produce strength and jumping power in soccer playersLa medición de la capacidad de oxigenación del músculo en reposo está bajo investigación en los deportes de equipo. El objetivo del presente estudio fue observar los cambios, después de una pretemporada, en la saturación de oxígeno muscular (SmO2) en reposo y la relación con la composición corporal y la potencia de salto en los jugadores de fútbol. Participaron 17 jugadores de fútbol (edad 21.8 ± 2.2 años). Se evaluó la composición corporal, el somatotipo, el salto de contramovimiento (CMJ) y el salto de contramovimiento de una sola pierna (SLCMJ). Simultáneamente, se midió la SmO2 en reposo en el músculo gastrocnemio utilizando la técnica de oclusión arterial en la pierna dominante y no dominante. Todas las mediciones se realizaron antes y después de la pretemporada. Se aplico la prueba t-student, la correlación de Pearson y la estadística de respuesta inter-individual de los sujetos para medir las magnitudes de cambio y el tamaño del efecto. Se observó una relación inversa entre SmO2 en la oclusión inicial (r= -0.82), la oclusión final (r= -0.79) y la recuperación de SmO2 (r= -0.82) con la potencia SLCMJ. También se observó una relación moderada entre el consumo de oxígeno y la masa grasa (r=0.64). La medición de SmO2 en reposo se puede considerar como un posible parámetro de rendimiento, porque se identificó su relación con la capacidad de producir fuerza y potencia de salto en jugadores de fútboActividad Física y Deport

Spanish version of the Talent Development Environment Questionnaire for sport: Cultural adaptation and initial validation

This study aimed to translate the Talent Development Environment Questionnaire into Spanish and provide an initial validation. A recommended methodology for translation and cultural adaptation of questionnaires was applied. Once this had been completed, three hundred and thirty-two young athletes completed the Talent Development Environment Questionnaire. The results revealed that the five factor solution Talent Development Environment Questionnaire was confirmed. With the exclusion of one item due to low factor loading, the Talent Development Environment Questionnaire-5 had robust statistical support for its factor structure (?2 (df = 305) = 499.64,

Análisis de la carga interna durante una temporada de balonmano femenino adolescente

Este estudio examina la carga interna basada en la frecuencia cardiaca (FC) durante una liga regional en jugadoras adolescentes de balonmano, comparando estos parámetros entre la primera y la segunda parte del partido. Un total de 10 jugadoras adolescentes de balonmano participaron en este estudio (edad 14,70 ± 0,67 años (rango, 14-15), masa corporal 55,78 ± 6,80 kg (rango, 46,70-68,90), talla 160,44 ± 8,53 cm (rango, 150,00-177,00), IMC 21,60 ± 1,10 kg/m2 (rango, 19,90-23,10), masa grasa 30,89 ± 3,70 % Masa Grasa (rango, 24,40-35,60) y VO2max 35,00 ± 1,00 ml·min·kg-1 (rango, 33,76-36,00)). El análisis de la frecuencia cardíaca (n=120) fue registrado durante 12 partidos oficiales usando monitores de frecuencia cardiaca. Las demandas individuales fueron categorizada en 6 zonas de intensidad basándose en el % Frecuencia Cardíaca Máxima (FCmáx): zona I: 0-50%; zona II: 51-60%; zona III: 61-70%; zona IV: 71-80%, zona V: 81-90 y zona VI: 91-100% de la FCmáx. La FCmáx Efectiva y Media durante el partido fueron 204,14±6,12 y 185,71±8,33 ppm, respectivamente. Durante la segunda parte, la frecuencia cardiaca máxima efectiva (201.71±5.23 vs 204.15±6.57 ppm; p=0.001) y media efectiva (183.51±8.61 vs 189.67±7.47 ppm; p=0.000) decrecieron en comparación con las primeras partes. Las jugadoras de balonmano adolescente desarrollaron una alta intensidad durante partidos oficiales, siendo más alta en la primera parte comparada con la segunda.This study examined the internal load based on heart rate (HR) in a teenage female handball team, which is playing in a regional league, comparing these parameters between the first and second half of the matches. A total of 10 adolescent female handball players participated in the study (age 14.70 ± 0.67 years (range, 14-15), weight 55.78 ± 6.80 kg (range, 46.70-68.90), height 160.44 ± 8.53 cm (range, 150.00-177.00), BMI 21.60 ± 1.10 kg/m2 (range, 19.90-23.10), fat mass 30.89 ± 3.70 % Fat Mass (range, 24.40-35.60) and VO2max 35.00 ± 1.00 ml·min·kg-1 (range, 33.76-36.00). Heart Rate (n=120) analyses were registered throughout 12 official matches using Heart Rate monitors. Individual demands were categorized into six intensity zones based on % Maximum Heart Rate (HRmax): zone I: 0-50%; zone II: 51-60%; zone III: 61-70%; zone IV: 71-80%, zone V: 81-90 and zone VI: 91-100% of HRmax. Effective maximum and mean Heart Rate in the total match were 204.14±6.12 and 185.71±8.33 b·min-1, respectively. During the second half, effective maximum (201.71±5.23 vs 204.15±6.57 b·min-1; p=0.001) and effective mean (183.51±8.61 vs 189.67±7.47 b·min-1; p=0.000). Heart Rate decreased comparing to the first half. Female adolescent team handball players develop a high intensity during official matches. This intensity is higher in first half compared to the second half.peerReviewe

High-intensity interval training in normobaric hypoxia leads to greater body fat loss in overweight/obese women than high-intensity interval training in normoxia

Un estímulo hipóxico moderado se considera una modalidad terapéutica prometedora para varios estados patológicos, incluida la obesidad. Hay pruebas científicas que sugieren que cuando se combinan la hipoxia y la actividad física, podrían aportar beneficios a la población obesa. El objetivo del presente estudio fue investigar si la exposición a la hipoxia combinada con dos protocolos diferentes de ejercicio de intervalo de alta intensidad en mujeres con sobrepeso/obesas era más eficaz en comparación con el ejercicio en la normoxia. Los participantes en el estudio incluyeron 82 mujeres con sobrepeso/obesas, que iniciaron un programa de 12 semanas de 36 sesiones, y fueron divididas al azar en cuatro grupos: (1) entrenamiento de intervalo aeróbico en hipoxia (AitH; FiO2 = 17,2%; n = 13), (2) entrenamiento de intervalo aeróbico en normoxia (AitN; n = 15), (3) entrenamiento de intervalo de sprint en hipoxia (SitH; n = 15), y (4) entrenamiento de intervalo de sprint en normoxia (SitN; n = 18). Se evaluaron la masa corporal, el índice de masa corporal, el porcentaje de masa grasa total, la masa muscular, el índice metabólico basal, la oxidación de grasas y carbohidratos y la energía de las grasas y los carbohidratos. Los resultados se midieron en la línea de base (T1), después de 18 sesiones de entrenamiento (T2), 7 días después de la última sesión (T3) y 4 semanas después de la última sesión (T4). La masa grasa en el grupo SitH se redujo significativamente en comparación con el grupo SitN de T1 a T3 (p < 0,05) y de T1 a T4 (p < 0,05) y la masa muscular aumentó significativamente de T1 a T4 (p < 0,05). La masa grasa en el grupo AitH disminuyó significativamente (p < 0,01) y la masa muscular aumentó (p = 0,022) en comparación con el grupo AitN de T1 a T4. Todos los grupos de entrenamiento mostraron una reducción del porcentaje de masa grasa, con una reducción estadísticamente significativa en los grupos de hipoxia (p < 0,05). La masa muscular aumentó significativamente en los grupos de hipoxia (p < 0,05), especialmente en T4. Mientras que la oxidación de las grasas tendió a aumentar y la oxidación de los hidratos de carbono tendió a disminuir en ambos grupos de hipoxia, la tendencia se invirtió en los grupos de normoxia. Así pues, el entrenamiento con intervalos de alta intensidad bajo hipoxia intermitente normobárica durante 12 semanas en mujeres con sobrepeso/obesas parece ser prometedor para reducir el contenido de grasa corporal con un aumento concomitante de la masa muscular.A moderate hypoxic stimulus is considered a promising therapeutic modality for several pathological states including obesity. There is scientific evidence suggesting that when hypoxia and physical activity are combined, they could provide benefits for the obese population. The aim of the present study was to investigate if exposure to hypoxia combined with two different protocols of high-intensity interval exercise in overweight/obese women was more effective compared with exercise in normoxia. Study participants included 82 overweight/obese women, who started a 12 week program of 36 sessions, and were randomly divided into four groups: (1) aerobic interval training in hypoxia (AitH; FiO2 = 17.2%; n = 13), (2) aerobic interval training in normoxia (AitN; n = 15), (3) sprint interval training in hypoxia (SitH; n = 15), and (4) sprint interval training in normoxia (SitN; n = 18). Body mass, body mass index, percentage of total fat mass, muscle mass, basal metabolic rate, fat, and carbohydrate oxidation, and fat and carbohydrate energy were assessed. Outcomes were measured at baseline (T1), after 18 training sessions (T2), 7 days after the last session (T3), and 4 weeks after the last session (T4). The fat mass in the SitH group was significantly reduced compared with the SitN group from T1 to T3 (p < 0.05) and from T1 to T4 (p < 0.05) and muscle mass increased significantly from T1 to T4 (p < 0.05). Fat mass in the AitH group decreased significantly (p < 0.01) and muscle mass increased (p = 0.022) compared with the AitN group from T1 to T4. All training groups showed a reduction in the percentage of fat mass, with a statistically significant reduction in the hypoxia groups (p < 0.05). Muscle mass increased significantly in the hypoxia groups (p < 0.05), especially at T4. While fat oxidation tended to increase and oxidation of carbohydrates tended to decrease in both hypoxia groups, the tendency was reversed in the normoxia groups. Thus, high-intensity interval training under normobaric intermittent hypoxia for 12 weeks in overweight/obese women seems to be promising for reducing body fat content with a concomitant increase in muscle mass.• Junta de Extremadura. Ayuda GR15020, para el Grupo de investigación GAEDAF • Ministerio de Educación, Cultura y Deporte. Beca FPU15/00450peerReviewe

Efeitos de intervenções multicomponentes em marcadores bioquímicos em jovens obesos: um protocolo de revisão sistemática

Physical exercise is effective in modulating circulating inflammatory markers of obesity. However, little is known about the effects of interventions with physical exercise programs accompanied by nutritional and/or psychological guidance, configuring themselves as multicomponent programs. Thus, the aim of this review is to systematically evaluate the evidence related to the effects of multicomponent weight-loss interventions in modulating circulating inflammatory markers in children and adolescents. Therefore, the following databases will be searched to identify all relevant articles: PubMed, SciELO, Lilacs, Web of Science, EMBASE, Scopus, SPORT Discus. Randomized controlled trials and quasi-experimental studies of children and adolescents (6 to 18 years old) will be included. Eligible interventions will target weight-related behaviors (including diet, physical activity, behavior modification and/or combinations thereof ). Two independent reviewers will select studies using Rayyan QCRI software and extract the data to a standard form. The main outcomes of the review will be the circulating values of leptin, interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF- α) in a quantitative way. To assess the methodological quality (or risk of bias) of individual studies, Effective Public Health Practice Project assessment tool will be used. The meta-analysis will be performed using the Review Manager software.O exercício físico é eficaz na modulação dos marcadores inflamatórios circulantes da obesidade. Porém, pouco se sabe sobre os efeitos de intervenções com programas de exercícios físicos acompanhados de orientações nutricionais e/ou psicológicas, configurando-se como programas multicomponentes. Assim, o objetivo deste protocolo é propor uma revisão sistematicamente das evidências relacionadas aos efeitos de intervenções multicomponentes para perda de peso na modulação de marcadores inflamatórios circulantes em crianças e adolescentes. Para tanto, as seguintes bases de dados serão pesquisadas para identificar todos os artigos relevantes: PubMed, SciELO, Lilacs, Web of Science, EMBASE, Scopus, SPORT Discus. Serão incluídos ensaios clínicos randomizados e estudos quase experimentais com crianças e adolescentes (6 a 18 anos). As intervenções elegíveis terão como foco a melhora dos comportamentos relacionados ao peso (incluindo dieta, atividade física, modificação de comportamento e/ou combinações dos mesmos). Dois revisores independentes selecionarão estudos usando o software Rayyan QCRI e extrairão os dados em um formulário padrão. O principal resultado da revisão serão os valores circulantes de leptina, interleucina 6 (IL-6) e fator de necrose tumoral alfa (TNF-α) de forma quantitativa. Para avaliar a qualidade metodológica (ou risco de viés) de estudos individuais será utilizada a ferramenta de avaliação Effective Public Health Practice Project. A meta-análise será realizada no software Review Manager

A multicomponent intervention program with overweight and obese adolescents improves body composition and cardiorespiratory fitness, but not insulin biomarkers

Objective: To verify the effect of a multicomponent intervention with overweight/obese adolescents on physical fitness, body composition, and insulin biomarkers. Methods: A quasi-experimental study with 37 adolescents, aged 10 to 17 years, of both sexes, overweight and obese, allocated in two groups (Intervention—IG Group, n = 17; Control—GC Group, n = 20). The IGs were submitted to a multicomponent intervention for 6 months (three weekly sessions) consisting of physical exercises (sports, functional circuit, recreational, and water activities) and nutritional and psychological guidance. Participants were assessed before and after intervention on body composition [body mass index (BMI), body fat, waist circumference, and waist-to-hip ratio (WHR)], physical fitness [cardiorespiratory fitness (CRF) and abdominal strength], and biomarkers of insulin (glucose, insulin, evaluation of the homeostasis model of insulin, and resistin resistance). The prevalence of responders in both groups was obtained according to the theoretical model applied in previous studies similar to this one to determine the cutoff points for response to intervention. Poisson regression was used to verify the difference in the prevalence ratio (PR) of the interviewees between the groups. Results: The responders' prevalence between groups CG and IG showed significant differences for body fat (CG = 30.0%; IG = 70.6%; PR = 1.396; p < 0.001), WHR (CG = 30.0%; IG = 76.5%; PR = 1.730; p < 0.001), and CRF (CG = 15.0%; IG = 52.5%; PR = 1.580; p < 0.001). Conclusions: A 6-month multicomponent intervention program improved certain body composition parameters and the CRF of overweight and obese adolescents but did not improve insulin biomarkers. Clinical Trial Registration: Clinical Trials under Protocol ID: 54985316.0.0000.534

Acute effects of block jumps in female volleyball players: the role of performance level

Aunque el papel de la capacidad de salto en las jugadoras de voleibol es bien conocido, el efecto de la fatiga en esta habilidad no es bien conocido. El objetivo del presente estudio fue examinar el efecto de una serie de saltos en bloque (BJ) en la capacidad de salto y si varía según el nivel de rendimiento. Diez jugadores de voleibol femenino de élite (EG) y 11 aficionados (AG) realizaron una intervención de fatiga que consistió en 45 BJ, que se probaron para el salto de sentadilla (SJ), el salto de contramovimiento (CMJ) y BJ antes y después de la intervención. Índice de elasticidad (EI): (100 x (CMJ - SJ) / SJ) e índice de coordinación de las extremidades superiores (ULCI): se calcularon (100 x (BJ - CMJ) / CMJ). Después de la intervención, EG mostró una disminución de 4.40% en la altura de BJ (p = 0.04; ES = 0.40), mientras que AG presentó un aumento de 1.27%, que no fue significativo (p = 0.57; ES = 0.07). Sin embargo, EG y AG no presentaron diferencias significativas en SJ (p = 0.965 y p = 0.655) y CMJ (p = 0.742 yp = 0.211) cuando se compararon los valores iniciales con la intervención posterior. Aunque EI y ULCI no mostraron diferencias significativas después de la intervención en ningún grupo (AG: p = 0.989 y p = 0.114; EG: p = 0.242 yp = 0.205, respectivamente), AG presentó un tamaño de efecto medio (ES = 0.50) en EI y una pequeña en ULCI (ES = 0.37), también EG mostró un efecto medio-grande en ULCI (ES = 0.75). Estos hallazgos sugieren que el rendimiento de EG en BJ tiende a disminuir al final de una práctica específica de entrenamiento de salto. Por lo tanto, los entrenadores y preparadores físicos que trabajan con jugadores de voleibol de élite deben concentrarse en los ejercicios para mantener la capacidad de salto durante un partido.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 x (CMJ - SJ)/SJ) and upper limbs coordination index (ULCI): (100 x (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.• Junta de Extremadura. Ayuda GR15020peerReviewe