ABSTRACT
The purpose of this systematic review was: a) to determine the quality of evidence from studies assessing the effects of different lower limb strengthening protocols on muscle activity, strength, and power in sedentary and/or physically inactive subjects; and b) to determine the effectiveness of lower extremity strengthening protocols on muscle activity, strength, and power in sedentary and/or physically inactive subjects. Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statements were followed using keywords associated with strength training, lower limb, sedentary, and physical inactivity. Four databases were used: Medline via PubMed, Web of Science, Scopus and SPORTDiscus. Methodological quality was assessed using the PEDro scale. A total of 164 articles were retrieved, six included in this review. Four studies were classified as fair methodological quality, and two were considered of good methodological quality. Due to the heterogeneity in methodological aspects and the limited number of articles including the variables under study, it was not possible to establish a measure of effectiveness of lower limb strengthening protocols on muscle activity, strength, or power. In conclusion, strength training in the lower limb seems to improve the levels of strength, power, and muscular activity in sedentary subjects. However, due to the limited number of articles, methodological variability, and training methods used, it is necessary to conduct new studies that control these variables.(AU)
El propósito de esta revisión sistemática fue: a) determinar la calidad de la evidencia de los estudios que evaluaron los efectos de diferentesprotocolos de fortalecimiento de miembros inferiores sobre la actividad, la fuerza y la potencia muscular en sujetos sedentarios y/o físicamenteinactivos; y b) determinar la efectividad de los protocolos de fortalecimiento sobre la actividad, fuerza y potencia muscular de miembros infe-riores en sujetos sedentarios y/o físicamente inactivos. Se siguieron los criterios PRISMA (Preferred Reporting Items for Systematic Review andMeta-Analyse) utilizando palabras clave asociadas con el entrenamiento de fuerza, extremidades inferiores, sedentarismo e inactividad física. Serevisaron cuatro bases de datos: Medline vía PubMed, Web of Science, Scopus y SPORTDiscus. La calidad metodológica se evaluó mediante laescala PEDro. Se recuperaron 164 artículos en total, seis incluidos en esta revisión. Cuatro estudios se clasificaron como de calidad metodológicaregular y dos se consideraron de buena calidad metodológica.Debido a la heterogeneidad en los aspectos metodológicos y al escaso número de artículos que incluyeron las variables en estudio, no fue posibleestablecer una medida de efectividad de los protocolos de fortalecimiento de miembros inferiores sobre la actividad, la fuerza o la potenciamuscular. En conclusión, el entrenamiento de fuerza en el miembro inferior parece mejorar los niveles de fuerza, potencia y actividad muscular ensujetos sedentarios. No obstante, debido al número limitado de artículos, la variabilidad metodológica y los métodos de entrenamiento utilizados,es necesario realizar nuevos estudios que controlen estas variables.(AU)
Subject(s)
Humans , Male , Female , Clinical Protocols , Lower Extremity/injuries , Muscle Strength , Sedentary Behavior , Plyometric Exercise , Resistance TrainingABSTRACT
CONTEXT: Current devices to assess strength performance in handball may not be sufficiently sports-specific and reliable methods. Functional electromechanical dynamometry is a new technology that allows the development of accurate strength tests in athletes. PURPOSE: To determine the absolute and relative reliability and to compare the reliability of the right and left side, and mean and peak force of 3 specific strength tests in handball players with a functional electromechanical dynamometer: unilateral pullover, standing lift, and step forward. METHODS: Fourteen male handball players of the first Spanish division (28.79 [4.81] y; 10.38 [4.63] y of professional experience) performed a repeated-measurement design. Three testing sessions were performed (one per week). The first measurement consisted of 4 isometric tests (right and left unilateral pullover, and right and left standing lift) to obtain isometric peak force, and in the second and third sessions, 6 incremental tests until failure (right and left unilateral pullover, and right and left standing lift, right and left step forward) were performed. RESULTS: The tests provided high reliability or acceptable reliability for mean and peak strength of unilateral pullover, standing lift and step forward (intraclass correlation coefficient = .83-.97; coefficient of variation = 3.90-11.57). Effect side was negligible in any of the parameters, except for a small effect side in the left peak force for unilateral pullover and a small effect side on the left side for a step forward. Significant differences in reliability (coefficient of variation ratio > 1.15) were found between the right and left sides and peak and mean force in all exercises except peak force in unilateral pullover and step forward. CONCLUSION: These results confirm that the tests could be applied to assess physical performance in handball at the same time as regular gym training. Moreover, this is an excellent opportunity to individualize the player's weekly load.
Subject(s)
Muscle Strength , Sports , Humans , Male , Reproducibility of Results , Athletes , ExerciseABSTRACT
Introduction: The purpose of this systematic review was: a) to determine the quality of evidence from studies assessing the effects of different lower limb strengthening protocols on muscle activity, strength, and power in sedentary and/or physically inactive subjects; and b) to determine the effectiveness of lower extremity strengthening protocols on muscle activity, strength, and power in sedentary and/or physically inactive subjects. Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statements were followed using keywords associated with strength training, lower limb, sedentary, and physical inactivity. Four databases were used: Medline via PubMed, Web of Science, Scopus and SPORTDiscus. Methodological quality was assessed using the PEDro scale. A total of 164 articles were retrieved, six included in this review. Four studies were classified as fair methodological quality, and two were considered of good methodological quality. Due to the heterogeneity in methodological aspects and the limited number of articles including the variables under study, it was not possible to establish a measure of effectiveness of lower limb strengthening protocols on muscle activity, strength, or power. In conclusion, strength training in the lower limb seems to improve the levels of strength, power, and muscular activity in sedentary subjects. However, due to the limited number of articles, methodological variability, and training methods used, it is necessary to conduct new studies that control these variables.
Introducción: El propósito de esta revisión sistemática fue: a) determinar la calidad de la evidencia de los estudios que evaluaron los efectos de diferentes protocolos de fortalecimiento de miembros inferiores sobre la actividad, la fuerza y la potencia muscular en sujetos sedentarios y/o físicamente inactivos; y b) determinar la efectividad de los protocolos de fortalecimiento sobre la actividad, fuerza y potencia muscular de miembros inferiores en sujetos sedentarios y/o físicamente inactivos. Se siguieron los criterios PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyse) utilizando palabras clave asociadas con el entrenamiento de fuerza, extremidades inferiores, sedentarismo e inactividad física. Se revisaron cuatro bases de datos: Medline vía PubMed, Web of Science, Scopus y SPORTDiscus. La calidad metodológica se evaluó mediante la escala PEDro. Se recuperaron 164 artículos en total, seis incluidos en esta revisión. Cuatro estudios se clasificaron como de calidad metodológica regular y dos se consideraron de buena calidad metodológica. Debido a la heterogeneidad en los aspectos metodológicos y al escaso número de artículos que incluyeron las variables en estudio, no fue posible establecer una medida de efectividad de los protocolos de fortalecimiento de miembros inferiores sobre la actividad, la fuerza o la potencia muscular. En conclusión, el entrenamiento de fuerza en el miembro inferior parece mejorar los niveles de fuerza, potencia y actividad muscular en sujetos sedentarios. No obstante, debido al número limitado de artículos, la variabilidad metodológica y los métodos de entrenamiento utilizados, es necesario realizar nuevos estudios que controlen estas variables.
Subject(s)
Muscle Strength , Resistance Training , Humans , Muscle Strength/physiology , Sedentary Behavior , Lower Extremity , Resistance Training/methods , Muscles , Meta-Analysis as Topic , Systematic Reviews as TopicABSTRACT
The use of strength training is important for athletes in combat sports such as judo and jiu-jitsu. Specificity is key when prescribing strength training programs for athletes, considering maximal strength, muscular power and strength-endurance. Grappling combat sports require grip control, which is necessary to execute throwing techniques and groundwork. The aim of this study was to verify the bilateral strength deficit in general and in grappling combat sport-specific action in the control group and grapplers. A sample of 73 subjects, divided into 2 groups, was used: the Student Group (15 females and 16 males) and the Grappler Group (29 males and 13 females). The male and female participants attended four laboratory sessions over a 48-hour interval, the first two to familiarize themselves with the Electromechanical Functional Dynamometer (EMFD), and the last two to collect maximal isometric strength data, using a standard grip and a judo/jiujitsu specific grip. Significant differences in mean and peak forces (p < 0.001) were found, with high performance combat sport athletes having greater maximal isometric strength compared to students both bilaterally and unilaterally (p < 0.001). All comparisons also indicated higher values for males compared to females (p < 0.001). The results suggest that specific training in combat sports as well as sex differences play a significant role in maximal isometric strength performance. The type of grip used affects the application of force in the upper limb isometric strength tests, finding a main effect of grip type (p < 0.001), with the standard grip obtaining higher levels. However, the dominance between hands remains constant. More research is needed on specific judogi/jiu-jitsu-gi grips and their impact on maximal isometric strength with the EMFD.
ABSTRACT
The aim of this study was to determine if specific physical tests are sufficiently discriminant to differentiate players of similar anthropometric characteristics, but of different playing levels. Physical tests were conducted analyzing specific strength, throwing velocity, and running speed tests. Thirty-six male junior handball players (n = 36; age 19.7 ± 1.8 years; 185.6 ± 6.9 cm; 83.1 ± 10.3 kg; 10.6 ± 3.2 years of experience) from two different levels of competition participated in the study: NT = 18 were world top-level elite players, belonging to the Spanish junior men's national team (National Team = NT) and A = 18 players of the same age and anthropometric conditions, who were selected from Spanish third league men's teams (Amateur = A). The results showed significant differences (p < 0.05) between the two groups in all physical tests, except for two-step-test velocity and shoulder internal rotation. We conclude that a battery combining the Specific Performance Test and the Force Development Standing Test is useful in identifying talent and differentiating between elite and sub-elite players. The current findings suggest that running speed tests and throwing tests are essential in selecting players, regardless of age, sex, or type of competition. The results shed light on the factors that differentiate players of different levels and can help coaches in selecting players.
Subject(s)
Athletic Performance , Running , Male , Humans , Adolescent , Young Adult , Adult , Athletes , Exercise Test/methods , AnthropometryABSTRACT
It is currently unknown the most effective potentiation protocol to increase maximum strength. Hence, we investigated the separated and combined effects of post-tetanic potentiation (PTP) induced by whole-body electrostimulation (WB-EMS) and post-activation potentiation (PAP) induced by voluntary maximum isometric contractions on maximum isometric strength. Ten trained males were randomly evaluated on four occasions. In session A, maximum isometric strength (split squat) was measured in minutes 1, 4, and 8. In session B, the measurements were taken in minutes 2, 6, and 10. In session C, a WB-EMS protocol was applied to elicit PTP and the measurements were performed in minutes 1, 4, and 8. In session D, the same WB-EMS protocol was applied and the measurements were taken in minutes 2, 6, and 10. No significant differences in maximum isometric strength were observed between: (i) the control and WB-EMS in minutes 1 vs. 1 and 2 vs. 2; (ii) the control and PAP in minutes 1 vs. 4, 1 vs. 8, 2 vs. 6, and 2 vs. 10; and (iii) the PAP and WB-EMS plus PAP in minutes 4 vs. 4, 8 vs. 8, 6 vs. 6, and 10 vs. 10. In contrast, the WB-EMS plus PAP revealed a significant increase of 54% (~450 N) compared to the WB-EMS in minutes 4 and 8 compared to the minute 1 (p < 0.001), but not between minutes 2 vs. 6 and 2 vs. 10. The present results showed that PTP induced by WB-EMS in isolation or combined with PAP induced by voluntary maximum isometric contractions did not produce a significant increase in maximum isometric strength compared to the control and PAP alone, respectively.
ABSTRACT
AIM: To determine the absolute and relative reliability of functional trunk tests, using a functional electromechanical dynamometer to evaluate the isokinetic strength of trunk flexors and to determine the most reliable assessment condition, in order to compare the absolute and relative reliability of mean force and peak force of trunk flexors and to determine which isokinetic condition of evaluation is best related to the maximum isometric. METHODS: Test-retest of thirty-seven physically active male student volunteers who performed the different protocols, isometric contraction and the combination of three velocities (V1 = 015 m s-1 , V2 = 0.30 m s-1, V3 = 0.45 m s-1) and two range of movement (R1 = 25% cm ; R2 = 50% cm) protocols. RESULTS: All protocols to evaluate trunk flexors showed an absolute reliability provided a stable repeatability for isometric and dynamic protocols with a coefficient of variation (CV) being below 10% and a high or very high relative reliability (0.69 < intraclass correlation coefficient [ICC] > 0.86). The more reliable strength manifestation (CV = 6.82%) to evaluate the concentric contraction of trunk flexors was mean force, with 0.15 m s-1 and short range of movement (V1R1) condition. The most reliable strength manifestation to evaluate the eccentric contraction of trunk flexors was peak force, with 0.15 m s-1 and a large range of movement (V1R2; CV = 5.07%), and the most reliable way to evaluate isometric trunk flexors was by peak force (CV = 7.72%). The mean force of eccentric trunk flexor strength with 0.45 m s-1 and short range of movement (V3R1) condition (r = 0.73) was best related to the maximum isometric contraction. CONCLUSION: Functional electromechanical dynamometry is a reliable evaluation system for assessment of trunk flexor strength.
ABSTRACT
Introducción: El Complex Training se ha utilizado para lograr la potenciación post-activación (PAP) de las capacidades físicas y, al hacerlo, mejorar el rendimiento deportivo de los atletas. Sin embargo pocos estudios han considerado una activación con intensidades en zonas de potencia. Objetivo: Determinar el efecto agudo de un protocolo de Complex Training en press banca sobre la velocidad del lanzamiento de la granada en pentatletas militares. Método: Diecinueve pentatletas militares fueron parte del estudio. El estudio tuvo un diseño cuasi experimental intrasujeto. El protocolo de Complex Training consistió en: 4 series de 5 repeticiones al 30% de 1RM + 4 repeticiones al 60% de 1RM + 3 lanzamientos de granada separada por 15 segundos. Las variables medidas fueron: velocidad máxima (Vmax) y promedio (Vpro) del lanzamiento de la granada a través de un Radar Gun, las potencias máximas (Pmax) y promedio (V pro) en press banca a través de un encoder lineal y concentraciones de lactato [La] post esfuerzo. Para el análisis estadístico se utilizó ANOVA de medias repetidas y para el tamaño del efecto la prueba Eta Cuadro Parcial. Resultados: La Vmax, Vpro y Pmax no presentaron modificaciones significativas entre la serie control y las cuatro series experimentales (p = 0,90; p = 0,94; p = 0,06). Sin embargo las Ppro de press banca y las [La] sufrieron un descenso significativo (p = 0,002; p = 0,001). Conclusiones: Los resultados del estudio no mostraron efectos positivos del protocolo de Complex Training sobre las velocidades de lanzamiento de la granada en pentatletas militares, por lo tanto no se consiguió PAP en la musculatura involucrada en el lanzamiento del proyectil. También se observó fatiga general y local durante la aplicación del protocolo. Se sugiere seguir indagando las cargas de activación realizando cambios en la intensidad y pausas de las cargas
Introduction: Complex Training (CT) has been used to achieve Post-activation Potentiation (PAP) of physical capabilities and, in doing so, improve athletes sports performance, however few studies have taking into account an activation with intensities in power zones. Objective: To determine the acute effect of Complex Training on bench press on grenade throwing velocity on military pentathletes. Method: Nineteen military pentathletes were part of the study. The study had a quasi-experimental intra-subject design. The Complex Training protocol consisted of 4 sets of 5 repetitions at 30% one Repetition Maximum (1RM) + 4 repetitions at 60% 1RM + 3 grenade throws with a 15-second rest. The measured variables were: maximum velocity and grenade throw average through a Radar Gun, peak power and bench press average through a lineal encoder and post-effort Lactate [La]. For the statistical analysis repeated measures of ANOVA was used, and for the size of the effect an Eta-squared test was used. Results: The maximum velocity, average velocity and peak power did not show significant modifications between the control series and the 4 experimental series (p = 0.90; p = 0.94; p = 0.06). However, the average power of bench press and [La] showed a significant fall (p = 0.002: p = 0.001). Conclusions: The results of the study did not show effects in Complex Training on maximum and average velocity of grenade throwing in military pentathletes; hence, Post Activation Potentiation was not reached in the muscles involved in the projectile throwing. General and local fatigue was also observed during the application of the protocol. It is recommended to continue researching on activation loads, performing changes in the intensity and pauses of each load
Subject(s)
Humans , Muscle Strength/physiology , Athletic Performance/physiology , Resistance Training/methods , Track and Field/physiology , Physical Conditioning, Human/methodsABSTRACT
Introducción: Tanto la Resistencia Variable (RV) como la Potenciación Post Activación (PAP) han sido utilizadas como metodologías de entrenamiento para mejorar la fuerza explosiva en deportistas, pero hasta el momento no se sabe cuántas investigaciones existen en las principales bases de datos que relacionen ambas variables. Objetivo: Investigar cuáles fueron los métodos de RV utilizados para generar PAP entre enero de 2011 y enero de 2016. El objetivo secundario fue visualizar las intensidades de estimulación y los cambios en los niveles de fuerza explosiva reportados en cada uno de los estudios consultados. Método: El diseño corresponde a una Revisión Sistemática de los estudios previamente publicados que relacionaron la RV con PAP. La búsqueda sistemática incluyó artículos publicados desde enero de 2011 a enero de 2016 en Web of Science (WOS), Scopus, Sport Discuss, PubMed y Medline. Para la selección de los estudios, se identificaron sólo aquellos artículos que usaron RV como metodología de entrenamiento para generar PAP. Resultados: Se identificaron nueve artículos, los cuales fueron estratificados según el entrenamiento que realizaban: (i) Resistencia variable intra-sesión (n = 3), (ii) Resistencia variable intra-repetición (n =1) y (iii) Resistencia variable intra-serie (n = 5). Por otro lado, ocho de los nueve estudios consultados estuvieron centrados en los miembros inferiores y ninguno de forma específica en los miembros superiores. También se pudo observar, que todos aquellos estudios que reportaron cambios significativos en la fuerza explosiva trabajaron sobre el 80 % de 1RM. Conclusiones: No existe evidencia suficiente para conocer el verdadero efecto de la RV sobre la PAP, más aún en los miembros superiores. Sin embargo, hay indicios que la resistencia variable intra-serie puede generar cambios agudos en los niveles de fuerza explosiva trabajando sobre un 80 % de 1RM
Introduction: The Variable Resistance (VR), as well as the Post-Activation Potentiation (PAP) have been used as training methodologies to improve the explosive strength in athletes. By the moment, there is no specific knowledge of the number of investigations connecting both variables that exist in the main data bases. Objective: The aim of this study was to find out which were the VR methods used to generate PAP between January 2011 and January 2016. The secondary aim was to visualize the stimulus intensity and the variations in the explosive strength levels recounted in every one of the studies consulted for this research. Method: the design is a systematic revision of the studies previously published that connected VR with PAP. The systematic research included articles published since January 2011 until January 2016 in the Web of Science (WOS), Scopus, Sport Discuss, PubMed, and Medline. For the studies selection, only those articles using VR as a training methodology to generate PAP were identified. Results: Nine articles were identified, which were stratified according to the training performed: (i) Intra-Session Variable Resistance (n = 3), (ii) Intra-Repetition Variable Resistance (n = 1), and (iii) Intra-Set Variable Resistance (n = 5). On the other hand, eight out of nine studies were focused on the lower limbs and none of them focused specifically on the upper limbs. It was also observed that all those studies showing significant variation in explosive strength worked with over 80 % 1RM. Conclusions: There is no conclusive evidence to identify the real effect of VR over PAP, and clearly not for the upper limbs. However, there are indicators that the Intra-Set Variable Resistance can generate acute changes in the explosive strength levels working over 80 % 1RM
