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1.
J Strength Cond Res ; 35(Suppl 12): S70-S75, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32149873

RESUMEN

ABSTRACT: Hajek, F, Keller, M, Taube, W, von Duvillard, SP, Bell, JW, and Wagner, H. Testing-specific skating performance in ice hockey. J Strength Cond Res 35(12S): S70-S75, 2020-Skating performance generally determines overall performance in ice hockey but has not been measured adequately in the past. Consequently, the aim of the study was to develop and validate a specific overall skating performance test for ice hockey (SOSPT) that includes similar movements and intensities as in competition. Ten male elite under-14-year and under-18-year old ice hockey players performed the SOSPT (2 heats only) and a 40-m on-ice sprinting test twice within 8 days. Additionally, 14 under-15, 18 under-17, and 20 under-20 male elite ice hockey players performed only the SOSPT (4 heats). Time was measured from the first subject's movement during a V-start until crossing the line (40-m on-ice sprinting test), first touch of the shoulder on the mat (heat #1 in the SOSPT) or first touch of the puck with the stick (heat #2 in the SOSPT) using a hand stopwatch. We found a high test-retest reliability of the SOSPT and 40-m on-ice sprinting test (interclass correlation coefficient, >0.7; coefficient of variation, <5%) with highly significant differences (p < 0.001) between the under-15, under-17, and under-20 players, a high correlation (r > 0.70) between an expert rating and the SOSPT, and a low correlation between the 40-m on-ice sprinting test and the SOSPT in the under-14 and under-18 players. The results of the study reveal that the SOSPT is a reliable and valid test to determine the specific overall skating performance in ice hockey players and is more suitable compared with straight skating tests of the 40-m on-ice sprinting test.


Asunto(s)
Hockey , Patinación , Prueba de Esfuerzo , Humanos , Masculino , Movimiento , Reproducibilidad de los Resultados
2.
J Sports Sci Med ; 20(3): 492-499, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34267589

RESUMEN

The aim of this study was to determine whether the first sensation of stretching (ROMFSS) may predict the maximum range of motion (ROMMAX) in male (N = 37) and female (N = 32) volunteer subjects, and to assess the reliability of the ROM perceived by subjects in relation to a pre-determined ROM (ROM50%). Subjects attempted three experimental sessions with 48 hours between sessions 1 and 2 and 28 days between sessions 1 and 3. Within each session, five trials were performed with isokinetic equipment to assess posterior thigh muscle flexibility. The results revealed a strong and significant correlation between ROMMAX and ROMFSS for both sexes, females (r = 0.96, p < 0.001, R2 = 0.92) and males (r = 0.91, p < 0.001; R2 = 0.82). The accuracy of the model verified by the standard error of estimate (SEE) was high in the equations proposed for both female (SEE = 4.53%) and male (SEE = 5.45%). Our results revealed that ROMFSS may predict the ROMMAX for both male and female subjects. The ROMFSS may contribute to the development of evaluation methods that do not subject the individuals to conditions that may include unnecessary risk of injury and is well suited to monitor the training process of stretching exercises with submaximal loads.


Asunto(s)
Ejercicios de Estiramiento Muscular/fisiología , Músculo Esquelético/fisiología , Sensación/fisiología , Femenino , Humanos , Masculino , Músculo Esquelético/lesiones , Percepción/fisiología , Factores de Riesgo , Muslo
3.
J Sports Sci ; 37(21): 2411-2419, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31280702

RESUMEN

There are well-known biological differences between women and men, especially in technical-coordinative variations that contribute to sex differences in performance of complex movements like the most important offensive action in volleyball, the spike jump. The aim of this study was to investigate sex-dependent performance and biomechanical characteristics in the volleyball spike jump. Thirty female and male sub-elite volleyball players were analysed while striking a stationary ball with maximal spike jump height. Twelve MX13 Vicon cameras with a cluster marker set, two AMTI force plates, surface EMG, and a Full-Body 3D model in Visual3D were used. Main findings include sex differences (P< .05) in jump height (pη2 = .73), approach [speed (pη2 = .61), step length], transition strategy [plant angle, neuromuscular activation (pη2 = .91), horizontal force maxima and impulses], acceleration distances [centre of mass displacement (pη2 = .21), minimal knee and hip angles], use of torso and arms [incline, angular velocity (pη2 = .23)]. Correlations support that the results cannot be explained fully by strength and power differences between sexes but represent the product of technical-coordinative variations. Their relevance is acknowledged for both sexes and numerous performance determinants displayed sex differences. The integration of such attributes into sex-specific training seems promising but its effect requires further investigation.


Asunto(s)
Rendimiento Atlético/fisiología , Destreza Motora/fisiología , Voleibol/fisiología , Aceleración , Fenómenos Biomecánicos , Femenino , Humanos , Extremidad Inferior/fisiología , Masculino , Músculo Esquelético/fisiología , Ejercicio Pliométrico , Factores Sexuales , Estudios de Tiempo y Movimiento , Torso/fisiología , Extremidad Superior/fisiología , Adulto Joven
4.
J Strength Cond Res ; 33(4): 1056-1064, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30707133

RESUMEN

Wagner, H, Sperl, B, Bell, JW, and von Duvillard, SP. Testing specific physical performance in male team handball players and the relationship to general tests in team sports. J Strength Cond Res 33(4): 1056-1064, 2019-Team handball is exemplified by frequent changes in intensities and different complex movements during games, whereas physical performance has often been tested predominantly using standardized general tests. The study aimed (a) to determine the relationship between specific and general physical performance as well as between specific aerobic capacity and agility, and (b) to ascertain the relevance of these tests for strength and conditioning professionals. Seventy-two male indoor court players performed a game-based performance test (GBPT) including team handball-specific techniques, upper-body and lower-body strength tests, a 30-m sprint test, a countermovement jump Abalakov (CMJA) test (with arm swing), and an incremental treadmill-running test. To assess the specific physical performance using the general test performance, we used linear regression calculations. In addition, a principal component factor analysis was calculated. Linear regression analyses revealed a low correlation (R < 0.5) between specific and general aerobic performance, 30-m sprinting time and specific agility in the GBPT, jump height in the CMJA test and jump height in the jump shot, as well as isokinetic shoulder rotation torque and ball velocity in the jump shot. However, a moderate correlation (R > 0.5) was found between specific aerobic performance and specific agility in the GBPT. Principal component factor analysis yielded separate components for specific and general physical performance with a cumulative variance of 69%. The results of this study clearly indicated that general and team handball-specific performance are separate components. Recommendations to strength and conditioning professionals and coaches in team handball were presented.


Asunto(s)
Umbral Anaerobio , Prueba de Esfuerzo/métodos , Movimiento/fisiología , Rendimiento Físico Funcional , Deportes/fisiología , Adolescente , Adulto , Humanos , Masculino , Fuerza Muscular , Análisis de Componente Principal , Carrera/fisiología , Adulto Joven
5.
J Strength Cond Res ; 31(11): 3083-3093, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28968288

RESUMEN

Wagner, H, Gierlinger, M, Adzamija, N, Ajayi, S, Bacharach, DW, and von Duvillard, SP. Specific physical training in elite male team handball. J Strength Cond Res 31(11): 3083-3093, 2017-Specific physical training in elite team handball is essential for optimal player's performance; however, scientific knowledge is generally based on temporary training studies with subelite athletes. Therefore, the aim of the study was to analyze the effects of specific physical training in an elite male handball team over the entire season. Twelve players of a male handball team from the First Austrian Handball League conducted a 1-year specific physical training program in addition to their normal (team handball techniques and tactics) weekly training. Performance was measured with 5 general and 4 specific tests as well as game statistics during competition. Repeated measures analysis of variances and paired sample t-test were used to analyze differences in performance during training. We found a significant increase in oxygen uptake, offense time, defense time, fast break time, and jump height in the specific tests. Game performance statistics revealed a lower throwing percentage in the hosting team (59%) compared with the rival teams (63%). Our results indicated that specific endurance and agility are an acceptable modality in elite male team handball. However, performance in competition is strongly influenced by specific techniques and tactics. We recommend to strength and conditioning professionals that they tailor strength and power training, coordination and endurance as specific as possible, using free weights, agility exercises that include change in direction and jumps as well as short (10-15 seconds) high-intensity intervals.


Asunto(s)
Atletas , Rendimiento Atlético/fisiología , Entrenamiento de Fuerza/métodos , Deportes/fisiología , Adolescente , Adulto , Tamaño Corporal , Prueba de Esfuerzo , Humanos , Estudios Longitudinales , Masculino , Consumo de Oxígeno , Medicina Deportiva , Adulto Joven
6.
J Strength Cond Res ; 30(10): 2794-801, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24942169

RESUMEN

Wagner, H, Orwat, M, Hinz, M, Pfusterschmied, J, Bacharach, DW, von Duvillard, SP, and Müller, E. Testing game-based performance in team-handball. J Strength Cond Res 30(10): 2794-2801, 2016-Team-handball is a fast paced game of defensive and offensive action that includes specific movements of jumping, passing, throwing, checking, and screening. To date and to the best of our knowledge, a game-based performance test (GBPT) for team-handball does not exist. Therefore, the aim of this study was to develop and validate such a test. Seventeen experienced team-handball players performed 2 GBPTs separated by 7 days between each test, an incremental treadmill running test, and a team-handball test game (TG) (2 × 20 minutes). Peak oxygen uptake (V[Combining Dot Above]O2peak), blood lactate concentration (BLC), heart rate (HR), sprinting time, time of offensive and defensive actions as well as running intensities, ball velocity, and jump height were measured in the game-based test. Reliability of the tests was calculated using an intraclass correlation coefficient (ICC). Additionally, we measured V[Combining Dot Above]O2peak in the incremental treadmill running test and BLC, HR, and running intensities in the team-handball TG to determine the validity of the GBPT. For the test-retest reliability, we found an ICC >0.70 for the peak BLC and HR, mean offense and defense time, as well as ball velocity that yielded an ICC >0.90 for the V[Combining Dot Above]O2peak in the GBPT. Percent walking and standing constituted 73% of total time. Moderate (18%) and high (9%) intensity running in the GBPT was similar to the team-handball TG. Our results indicated that the GBPT is a valid and reliable test to analyze team-handball performance (physiological and biomechanical variables) under conditions similar to competition.


Asunto(s)
Rendimiento Atlético/fisiología , Prueba de Esfuerzo/métodos , Carrera/fisiología , Deportes/fisiología , Adolescente , Adulto , Frecuencia Cardíaca/fisiología , Humanos , Ácido Láctico/sangre , Masculino , Consumo de Oxígeno/fisiología , Reproducibilidad de los Resultados , Adulto Joven
7.
Nursing ; 46(1): 59-64, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26692313

RESUMEN

The authors evaluated the use of a new transfer device (roller tray) and compared it with three commonly used devices (slide board, nylon tube, and roller board). Caregivers experienced the greatest low back stress moving patients weighing 70 to 90 kg (approximately 150 to 200 lb). Qualitative data overwhelmingly favored the new roller tray with disposable absorbent underpads over the other devices. Caregivers experienced the greatest L4-5 torque not when transferring the heaviest patients (over 90 kg or approximately 200 lb), but rather when transferring those weighing 70 to 90 kg. These "middle-weight" patients are often moved using only two instead of three caregivers or a lift team, as are used for heavier patients. Caregivers should use three caregivers (two pullers and one pusher) even when patients are medium weight. The researchers' nursing faculty members are enthusiastic about using the new transfer device in their teaching stations.


Asunto(s)
Traumatismos de la Espalda/prevención & control , Movimiento y Levantamiento de Pacientes/instrumentación , Enfermería , Traumatismos Ocupacionales/prevención & control , Diseño de Equipo , Humanos , Movimiento y Levantamiento de Pacientes/enfermería
8.
J Sports Sci Med ; 14(4): 799-810, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26664277

RESUMEN

The purpose of the study was to measure the demands of off-road cycling via portable spirometry, leg-power output (PO), heart rate (HR) and blood lactate (BLa) concentration. Twenty-four male competitive cyclists (age: 29±7.2 yrs, height: 1.79 ± 0.05 m, body mass: 70.0 ± 4.9 kg, VO2peak: 64.9 ± 7.5 ml·kg(-1)·min(-1)) performed simulated mountain bike competitions (COMP) and laboratory tests (LabT). From LabT, we determined maximal workload and first and second ventilatory thresholds (VT1, VT2). A high-performance athlete (HPA) was used for comparison with three groups of subjects with different sport-specific performance levels. Load profiles of COMP were also investigated during uphill, flat and downhill cycling. During the COMP, athletes achieved a mean oxygen uptake (VO2COMP) of 57.0 ± 6.8 ml·kg(-1)·min(-1) vs. 71.1 ml·kg(-1)·min(-1) for the HPA. The POCOMP was 2.66±0.43 W·kg(-1) and 3.52 W·kg(-1) for the HPA. POCOMP, VO2COMP and HRCOMP were compared to corresponding variables at the VT2 of LabT. LabT variables correlated with racing time (RTCOMP) and POCOMP (p < 0.01 to <0.001; r-0.59 to -0.80). The VO2peak (LabT) accounted for 65% of variance of a single COMP test. VO2COMP, POCOMP and also endurance variables measured from LabTs were found as important determinants for cross-country performance. The high average VO2COMP indicates that a high aerobic capacity is a prerequisite for successful COMP. Findings derived from respiratory gas measures during COMPs might be useful when designing mountain bike specific training. Key pointsCross- country cycling is characterized by high oxygen costs due to the high muscle mass simultaneously working to fulfill the demands of this kind of sports.Heart rate and blood lactate concentration measures are not sensitive enough to assess the energy requirements of COMP. Therefore, respiratory gas and power output measures are helpful to provide new information to physiological profile of cross- country cycling.An excellent cycling-specific capacity is a prerequisite for successful off-road cycling.Data determined from LabT might be utilized to describe semi-specific abilities of MB- athletes on a cycle ergometer, while data originating from COMP might be useful when designing a mountain bike specific training.

9.
J Sports Sci Med ; 13(4): 808-16, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25435773

RESUMEN

Team handball is a complex sport game that is determined by the individual performance of each player as well as tactical components and interaction of the team. The aim of this review was to specify the elements of team-handball performance based on scientific studies and practical experience, and to convey perspectives for practical implication. Scientific studies were identified via data bases of PubMed, Web of Knowledge, SPORT Discus, Google Scholar, and Hercules. A total of 56 articles met the inclusion criteria. In addition, we supplemented the review with 13 additional articles, proceedings and book sections. It was found that the specific characteristics of team-handball with frequent intensity changes, team-handball techniques, hard body confrontations, mental skills and social factors specify the determinants of coordination, endurance, strength and cognition. Although we found comprehensive studies examining individual performance in team-handball players of different experience level, sex or age, there is a lack of studies, particularly for team-handball specific training, as well as cognition and social factors. Key PointsThe specific characteristics of team-handball with frequent intensity changes, specific skills, hard body confrontations, mental skills and social factors define the determinants of coordination, endurance, strength and cognition.To increase individual and team performance in team-handball specific training based on these determinants have been suggested.Although there are comprehensive studies examining individual performance in team-handball players of different experience level, sex, or age are published, there is a lack of training studies, particularly for team-handball specific techniques and endurance, as well as cognition and social factors.

10.
J Sports Sci ; 31(10): 1045-53, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23362842

RESUMEN

The purpose of the study was to assess the average physical intensity and energy expenditure during a single round of golf on hilly and flat courses in a heterogeneous group of healthy men and women of varying age and golf handicap. Forty-two males and 24 females completed an incremental cycle-ergometer exercise test to determine exercise performance markers. The heart rate (HR), duration, distance, walking speed, ascent and descent were measured via a global positioning system (GPS)/HR monitor during the game and energy expenditure was calculated. Playing 9 or 18-holes of golf, independent of the golf course design, the average HR was not significantly different between sexes or the subgroups. The intensities were light with respect to the percentage of maximal HR and metabolic equivalents of task (METs). Total energy expenditure of all participants was not significantly different for hilly (834 ± 344 kcal) vs. flat courses (833 ± 295 kcal) whereas male players expended significantly greater energy than female players (926 ± 292 vs. 556 ± 180 kcal), but did not have significantly greater relative energy expenditure (2.8 ± 0.8 vs. 2.2 ± 0.7 METs). As a high volume physical activity, playing golf is suggested to yield health benefits. Since the intensity was well below recommended limits, golf may have health related benefits unrelated to the intensity level of the activity.


Asunto(s)
Metabolismo Energético/fisiología , Ejercicio Físico/fisiología , Golf/fisiología , Frecuencia Cardíaca , Equivalente Metabólico , Esfuerzo Físico/fisiología , Factores Sexuales , Adulto , Anciano , Femenino , Sistemas de Información Geográfica , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Ambulatorio , Valores de Referencia , Caminata/fisiología , Adulto Joven
11.
Eur J Appl Physiol ; 112(8): 3079-86, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22194004

RESUMEN

The aim of the study was to investigate the independent relationship between maximal lactate steady state (MLSS), blood lactate concentration [La] and exercise performance as reported frequently. Sixty-two subjects with a wide range of endurance performance (MLSS power output 199 ± 55 W; range: 100-302 W) were tested on an electronically braked cycle ergometer. One-min incremental exercise tests were conducted to determine maximal variables as well as the respiratory compensation point (RCP) and the second lactate turn point (LTP2). Several continuous exercise tests were performed to determine the MLSS. Subjects were divided into three clusters of exercise performance. Dietary control was employed throughout all testing. No significant correlation was found between MLSS [La] and power output at MLSS. Additionally, the three clusters of subjects with different endurance performance levels based on power output at MLSS showed no significant difference for MLSS [La]. MLSS [La] was not significantly different between men and women (average of 4.80 ± 1.50 vs. 5.22 ± 1.52 mmol l(-1)). MLSS [La] was significantly related to [La] at RCP, LTP2 and at maximal power. The results of this study support previous findings that MLSS [La] is independent of endurance performance. Additionally, MLSS [La] was not influenced by sex. Correlations found between MLSS [La] and [La] at maximal power and at designated anaerobic thresholds indicate only an association of [La] response during incremental and MLSS exercise when utilizing cycle ergometry.


Asunto(s)
Tolerancia al Ejercicio , Ácido Láctico/sangre , Contracción Muscular , Músculo Esquelético/metabolismo , Resistencia Física , Recreación , Adulto , Umbral Anaerobio , Análisis de Varianza , Ciclismo , Biomarcadores/sangre , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Consumo de Oxígeno , Respiración , Factores Sexuales , Factores de Tiempo , Adulto Joven
12.
J Sports Sci ; 30(1): 21-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22111879

RESUMEN

The importance of proximal-to-distal sequencing in human performance throwing has been reported previously. However, a comprehensive comparison of the proximal-to-distal sequence in team-handball throwing in athletes with different training experience and competition is lacking. Therefore, the aim of the study was to compare the ball velocity and proximal-to-distal sequence in the team-handball standing throw with run-up of players of different skill (less experienced, experienced, and elite). Twenty-four male team-handball players (n = 8 for each group) performed five standing throws with run-up with maximal ball velocity and accuracy. Kinematics and ball trajectories were recorded with a Vicon motion capture system and joint movements were calculated. A specific proximal-to-distal sequence, where elbow flexion occurred before shoulder internal rotation, was found in all three groups. These results are in line with previous studies in team-handball. Furthermore, the results of the present study suggest that in the team-handball standing throw with run-up, increased playing experience is associated with an increase in ball velocity as well as a delayed start to trunk flexion.


Asunto(s)
Rendimiento Atlético/fisiología , Desempeño Psicomotor/fisiología , Adolescente , Adulto , Brazo/fisiología , Fenómenos Biomecánicos , Codo/fisiología , Humanos , Masculino , Rotación , Carrera/fisiología , Hombro/fisiología , Adulto Joven
13.
Int J Sports Physiol Perform ; 17(6): 901-907, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35235906

RESUMEN

PURPOSE: In elite team handball, talent identification and selection of the best young players is a fundamental process in several national federations and clubs; however, literature addressing the specific game-based performance in team handball is almost nonexistent. Consequently, the aim of the study was to assess and compare the team-handball-specific game-based performance of elite male team handball players of different ages. METHODS: Twelve under-23, 10 under-19, 10 under-17, and 10 under-15 elite male players performed the team-handball game-based performance test. During testing, oxygen uptake, heart rate, sprinting time in defense, offense, fast breaks, and fast retreats, as well as ball velocity and jump height in the jump shot, were measured. RESULTS: Significant differences (P < .05) between under-23, under-19, under-17, and under-15 players were found for absolute peak oxygen uptake, defense, offense and fast break time, ball velocity, and jump height in the game-based performance test, as well as in body weight and height. CONCLUSION: The results revealed that with increasing age, elite male team handball players are heavier and taller (body weight and height); faster (team-handball offense, defense, and fast break); jump higher and throw faster (in the team-handball jump shot); and perform better aerobically (absolute peak oxygen uptake). The better performance in the under-23 and under-19 players compared with male adult players competing in a lower National Federation league (not on top-elite level) demonstrates that highly specific game-based physical performance determines the potential for developing young male team handball players for competition at the top level.


Asunto(s)
Rendimiento Atlético , Adolescente , Adulto , Rendimiento Atlético/fisiología , Estatura , Peso Corporal , Prueba de Esfuerzo/métodos , Humanos , Masculino , Oxígeno
14.
Arch Phys Med Rehabil ; 92(10): 1527-33, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21872843

RESUMEN

OBJECTIVE: To compare the effectiveness of 2 different volumes of resistance training (RT) combined with aerobic training in residential cardiac rehabilitation (CR). DESIGN: Randomized prospective cohort study. SETTING: Center for inpatient CR. PARTICIPANTS: Patients (N=295) with a mean age ± SD of 62.7±11.7 years participated in the study. INTERVENTIONS: Patients were randomly divided into 2 groups (group 1 and group 2) with different volumes of RT; 2 sets × 12 repetitions (REPS) (group 1) and 3 sets × 15 REPS (group 2) per session, 2 times per week; each RT session consisting of 10 different resistance exercises. In addition, patients also completed continuous moderate intensity aerobic training composed of cycle ergometry 6 times per week for 17±4 minutes (mean ± SD) and walking 5 times per week for 45 minutes. MAIN OUTCOME MEASURES: At entry and after 26±4 (mean ± SD) days of CR, blood pressure, heart rate, maximal oxygen consumption, and maximal power determined during cycle ergometry, strength determined via RT, and blood biochemistries were assessed. Data were analyzed via a 2-way (group × time) repeated measures analysis of variance. RESULTS: Statistical analysis revealed equivalent improvements in exercise capacity, muscular strength, hemodynamics, and blood chemistries regardless of RT volume (comparison-wise type I error rate, α<.01). CONCLUSIONS: Our results show that nearly doubling (3 sets × 15 REPS vs 2 sets × 12 REPS) the volume of RT as part of a residential CR program does not yield further improvement in strength and cardiovascular risk factors.


Asunto(s)
Rehabilitación Cardiaca , Entrenamiento de Fuerza/métodos , Análisis de Varianza , Biomarcadores/análisis , Enfermedades Cardiovasculares/diagnóstico por imagen , Enfermedades Cardiovasculares/fisiopatología , Prueba de Esfuerzo , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular/fisiología , Consumo de Oxígeno/fisiología , Resistencia Física/fisiología , Estudios Prospectivos , Resultado del Tratamiento , Ultrasonografía
15.
J Pediatr Endocrinol Metab ; 24(7-8): 419-25, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21932575

RESUMEN

The purpose of this study was to evaluate the associations of visfatin and adiponectin concentrations with insulin resistance and body composition in regularly physically active pubertal girls. In 129 girls, aged 13-15 years (pubertal stages 3-5), visfatin, adiponectin, insulin resistance measured by homeostasis model assessment (HOMA), and body composition measured by dual-energy X-ray absorptiometry were evaluated. Visfatin concentration was related to HOMA and overall adiposity (body mass index, fat mass) markers, whereas adiponectin concentration was related to overall adiposity (fat mass), central adiposity (trunk fat) and fat free mass values. These relationships remained significant (p < 0.05) after adjusting for pubertal stage. Visfatin was independently related to body mass index (beta = 0.936; p = 0.0001) and HOMA (beta = 0.444; p = 0.039) indices, whereas adiponectin was independently related to fat free mass (beta = 0.889; p = 0.003) and trunk fat (beta = -0.468; p = 0.042) values. In conclusion, visfatin could be related to insulin resistance and overall adiposity indices, whereas adiponectin was related to different body composition values in regularly physically active pubertal girls.


Asunto(s)
Atletas , Composición Corporal , Citocinas/sangre , Resistencia a la Insulina , Nicotinamida Fosforribosiltransferasa/sangre , Grasa Abdominal/crecimiento & desarrollo , Absorciometría de Fotón , Adiponectina/sangre , Adiposidad , Adolescente , Índice de Masa Corporal , Femenino , Humanos , Actividad Motora , Pubertad/sangre
16.
J Sports Sci Med ; 10(1): 73-80, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-24149298

RESUMEN

In team-handball competition, the players utilize various throwing techniques that differ in the lower body movements (with and without run-up or jump). These different lower body movements influence changes in the upper body movements and thus also affect the performance. A comprehensive analysis of 3D-kinematics of team-handball throws that may explain these differences in performance is lacking. Consequently, the purpose of this study was (1) to compare performance (ball velocity and throwing accuracy) between the jump throw, standing throw with and without run-up, and the pivot throw; (2) to calculate the influence of kinematic parameters to ball velocity; and (3) to determine if these four throwing techniques differ significantly in kinematics. Three-dimensional kinematic data (angles, angular velocities and their timing, ball velocity and velocity of the center of mass) of 14 elite team-handball players were measured using an 8 camera Vicon MX13 motion capture system (Vicon, Oxford, UK), at 250 Hz. Significant difference was found between the four throwing techniques for ball velocity (p < 0. 001), maximal velocity of the center of mass in goal-directed movement (p < 0.001), and 15 additional kinematic variables (p < 0.003). Ball velocity was significant impacted by the run-up and the pelvis and trunk movements. Depending on floor contact (standing vs. jump throws), elite players in the study used two different strategies (lead leg braces the body vs. opposed leg movements during flight) to accelerate the pelvis and trunk to yield differences in ball velocity. However, these players were able to utilize the throwing arm similarly in all four throwing techniques. Key pointsElite team-handball players achieved the greatest ball velocity in the standing throw with run-up (100%), followed by the standing throw without run-up (93%), jump throw (92%) and pivot throw (85%).Depending on the floor contact (standing vs. jump throws) the elite players of the study used two different strategies (lead leg braces the body vs. opposed leg movements during flight) to accelerate the pelvis and trunk that caused differences in ball velocity.Elite team-handball players were able to utilize the throwing arm similarly in all four throwing techniques.

17.
J Sports Sci Med ; 10(4): 748-53, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-24149569

RESUMEN

We measured physiological responses of elderly recreational skiers of different fitness and skiing abilities. Six subjects (mean age: 61.2 ± 4.6 yrs; Wt: 76.8 ± 15.6 kg; Ht: 1.69 ± 0.10 m; BMI: 26.9 ± 5.0) were tested in a laboratory and during 30 and 75 min of recreational downhill skiing. Oxygen uptake (VO2), heart rate (HR), blood lactate (LA) concentration, and diastolic (DBP) and systolic (SBP) blood pressure were used to estimate energy demands while skiing. During maximal testing in a laboratory, subjects achieved a mean maximal VO2max of 28.2 ± 7.5 ml.kg(-1).min(-1) and a mean HRpeak of 165 ± 4 bpm (98 ± 1% of HRmax). Mean maximal workload measured on a cycle ergometer was 2.2 ± 0.7 W.kg(-1) with a mean LApeak of 7.4 ± 1 mmol.l(-1). During field testing, mean VO2 during skiing was 12 ± 2 ml.kg(-1).min(-1) (45 ± 16% of VO2max). Skiing VO2peak was 19 ± 5 ml. kg(-1).min(-1) (72 ± 23% of VO2max) was lower than VO2max in the lab (p = 0.04). Mean HR during skiing was 126 ± 2 bpm (77 ± 1% of HRmax from lab tests). Skiing HRpeak was 162 ± 2 bpm. This was not different from HRmax in the lab (p = 0.68). Mean LA after 30 and 75 min of skiing was not different (2.2 ± 0.8 mmol.l(-1) and 2.0 ± 0.8, respectively, p = 0.71). Both LA samples during skiing were lower than lab tests (p < 0.0001). There was no difference for DBP between field and laboratory tests; however, SBP increased after 30 min of skiing to 171 ± 20 (p < 0.009) and 165 ± 17 (p < 0.003) after 75 min. These remained below the mean peak SBP determined in lab tests (218+31). Mean oxygen demand during 30 and 75 min of recreational skiing is only 45% of VO2max while mean HR is 77% of HRmax. This departure from linearity not often seen in typical aerobic activities suggests that alpine skiing requires a combination of aerobic and anaerobic activity. Blood LA remained low during skiing suggesting that elderly skiers may govern their intensity via signals closer to VO2 and LA compared to HR or BP. Key pointsRecreational Alpine skiing for elderly population does not pose health risksBlood pressure and heart rate during recreational Alpine skiing is retain within normal limitsBlood lactate levels remain relatively low and do not contribute to fatigueOxygen uptake and blood lactate are better markers of intensity in elderly Alpine skier compared to heart rate and blood pressure.

18.
Eur J Cardiovasc Prev Rehabil ; 17(3): 296-302, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19741541

RESUMEN

BACKGROUND: Cardiovascular rehabilitation (CR) is an important component of care for patients with cardiovascular disease (CVD) and has been well documented and promoted by various health organizations and position statements worldwide. PURPOSE: The purpose of this study was to investigate whether patients readmitted to CR on average 16 months after their previous discharge, maintained the reduction in CVD risk factors, maintained or improved functional capacity, occurrence of adverse cardiovascular events, and possible modifications in prescribed medications. METHODS: Five hundred and seventy patients (60+/-10 years) underwent cycle ergometry and blood sampling at the beginning, the end of 21+/-2 days of the previous CR, and again at readmission to CR. The CR consisted of cycling for 17+/-4 min at frequency of six times a week and daily walking for 45 min at 60-70% of the maximal individual heart rate. RESULTS: Blood total cholesterol, low-density lipoprotein-cholesterol, triglycerides, and body mass index decreased significantly during CR. Resting blood pressure, maximal performance (watts), maximal oxygen uptake, and heart rate recovery improved significantly in 1 min (P<0.001). At readmission, all traditional CVD risk factors increased significantly, although medication was unchanged and angiotensin-converting enzyme inhibitors were partly replaced by angiotensin II receptor antagonists. Exercise performance remained unchanged. CONCLUSION: At readmission, we observed an increase in CVD risk factors, although, physical fitness remained stable. Thus, failure of lifestyle modification after CR indicates the cause for concern. Reinforcement of home setting sessions of CR patients or other strategies to enhance long-term compliance to lifestyle changes could reduce the observed attrition in CR benefits.


Asunto(s)
Rehabilitación Cardiaca , Fármacos Cardiovasculares/uso terapéutico , Terapia por Ejercicio , Cooperación del Paciente , Instituciones Residenciales , Conducta de Reducción del Riesgo , Anciano , Biomarcadores/sangre , Glucemia/metabolismo , Presión Sanguínea , Índice de Masa Corporal , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/fisiopatología , Distribución de Chi-Cuadrado , Tolerancia al Ejercicio , Femenino , Frecuencia Cardíaca , Humanos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Organización y Administración , Consumo de Oxígeno , Readmisión del Paciente , Aptitud Física , Recuperación de la Función , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
19.
J Sports Sci Med ; 9(1): 15-23, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-24149381

RESUMEN

The jump throw is the most applied throwing technique in team- handball (Wagner et al., 2008); however, a comprehensive analysis of 3D-kinematics of the team-handball jump throw is lacking. Therefore, the purpose of our study was: 1) to measure differences in ball release speed in team- handball jump throw and anthropometric parameters between groups of different levels of performance and (2) to analyze upper body 3D-kinematics (flexion/extension and rotation) to determine significant differences between these groups. Three-dimensional kinematic data was analyzed via the Vicon MX 13 motion capturing system (Vicon Peak, Oxford, UK) from 26 male team-handball players of different performance levels (mean age: 21.2 ± 5.0 years). The participants were instructed to throw the ball (IHF Size 3) onto a target at 8 m distance, and to hit the center of a square of 1 × 1 m at about eye level (1.75 m), with maximum ball release speed. Significant differences between elite vs. low level players were found in the ball release speed (p < 0.001), body height (p < 0.05), body weight (p < 0.05), maximal trunk internal rotation (p < 0.05), trunk flexion (p < 0.01) and forearm pronation (p < 0.05) as well as trunk flexion (p < 0.05) and shoulder internal rotation (p < 0.001) angular velocity at ball release. Results of our study suggest that team-handball players who were taller and of greater body weight have the ability to achieve a higher ball release speed in the jump throw, and that an increase in trunk flexion and rotation angular velocity improve the performance in team-handball jump throw that should result in an increase of ball release speed. Key pointsTeam-handball players who were taller and of greater body weight have the ability to achieve a higher ball release speed.An increase in trunk flexion, trunk rotation and shoulder internal rotation angular velocity should result in an increase of ball release speed.Trunk movements are normally well observable for experienced coaches, easy correctable and therefore practical to improve the performance in team-handball jump throw of low level players during training without using complex measurement devices.

20.
Int J Sports Physiol Perform ; 15(7): 1019-1025, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32534447

RESUMEN

PURPOSE: To determine the effect of in-season differential training on volleyball spike-jump technique and performance in elite-level female players. METHODS: During the season, spike jumps of 12 elite female players (Austrian Volleyball League Women) were recorded by 13 Qualisys Oqus cameras (250 Hz) and an AMTI force plate (1000 Hz). First measurement was made at the beginning of the investigation. Two identical measurements were repeated after a first and a second interval. The first interval served as control phase. The second interval was comparable in length and regular program but included differential training (6 wk, 8 sessions of 15-20 min) as a modified warm-up. It addressed specific performance determinants. Analyses of variances were calculated for the 3 measurements and for the development during control and intervention phase. RESULTS: Initial jump height (0.44 [0.09] m) changed by -4.5% during the control phase and +11.9% during the intervention (P < .001, ηp2=.70). All approach variables, arm backswing, and velocity-conversion strategy improved compared with the control phase (Δ%: 6.1-51.2%, P < .05, ηp2=.40-.80). Joint angles, countermovement depth, maximal angular velocities, and torso incline were not affected (Δ%: -2.9-9.1%, P = .066-.969, ηp2=.00-.27). CONCLUSIONS: In-season differential training led to technical adaptations and increased spike-jump height in elite female players. The differential training program allowed players to experience a range of adaptability and to adjust toward an individual optimum in technical components of performance determinants. Coaches are encouraged to apply technical differential training to elite athletes and to target biomechanical performance factors specifically.

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