RESUMO
Raw-crushed wind-turbine blade (RCWTB), a waste from the recycling of wind-turbine blades, is used as a raw material in concrete in this research. It contains not only fiberglass-composite fibers that bridge the cementitious matrix but also polyurethane and balsa-wood particles. Therefore, concrete containing RCWTB can be notably affected by moisture and temperature fluctuations and by exposure to high temperatures. In this research, the performance of five concrete mixes with 0.0%, 1.5%, 3.0%, 4.5%, and 6.0% RCWTB, respectively, is studied under moist/dry, alternating-sign-temperature-shock, and high-temperature-shock tests. Two damage mechanisms of RCWTB within concrete were found through these tests: on the one hand, micro-cracking of the cementitious matrix, which was verified by microscopic analyses and was dependent on concrete porosity; on the other, damage and degradation of the RCWTB components, as the polyurethane melted, and the balsa-wood particles burned. Both phenomena led to larger remaining-strain levels and reduced concrete compressive strength by up to 25% under temperature and humidity variations, although the bridging effect of the fiberglass-composite fibers was effective when adding RCWTB amounts higher than 3.0%. The compressive-strength loss after the high-temperature-shock test increased with the RCWTB content, reaching maximum values of 8% after an exposure time of 7 days. Statistical analyses revealed that effect of the RCA amount in the concrete was conditioned by the exposure times in all the tests. The accurate definition of those times is therefore key to set an RCWTB content in concrete that ensures its suitable behavior under the environmental conditions analyzed.
Assuntos
Materiais de Construção , Temperatura , Vento , Poliuretanos , ReciclagemRESUMO
Several studies have evidenced that children in out-of-home care (OOHC), including foster family care and residential care, reveal high levels of mental health disorders (ranging from 40% to 88%). This study examines the outcomes in mental health reported by key residential workers in a group of children and youth (N = 492) between 8-17 years old who were in residential child care (RCC) in Spain. The research also aims to explore the relationship between mental health outcomes and the provision of mental health services (i.e., receiving any mental health treatment) as well as the influence of child, family, and placement factors. The design of this study includes two measures: a baseline (T1) and a follow-up two years later (T2). The results indicated that 29.9% of young people enjoyed sustained mental health; 26% meaningful improvement in their mental health; 23.5% meaningful deterioration; and the remaining 20.5% showed no meaningful change. One of the main findings was that receiving mental health treatment had a significant impact on mental health outcomes. It is crucial to establish protocols and systematic detection tools to assess mental health and ensure detection and referral to proper treatment.
La investigación en el ámbito de la protección a la infancia ha destacado la presencia de un alto porcentaje de niños, niñas y adolescentes (NNA) en acogimiento residencial y familiar con trastornos de salud mental (entre el 40% y el 88%). Este estudio tiene como objetivo examinar los cambios experimentados en la salud mental de los NNA durante el proceso de acogida según informan sus educadores de referencia en un grupo de 492 NNA entre 8-17 años que se encontraban en hogares de protección en España. El estudio también tiene como objetivo explorar la relación entre los resultados en salud mental y el tratamiento recibido desde diferentes servicios de salud mental, además de la influencia que puedan ejercer factores del NNA, su familia o el proceso de protección. El diseño del estudio se basa en dos medidas: línea base (T1) y seguimiento dos años después (T2). Los resultados indican que el 29.9% de los NNA mantenía una buena salud mental en las dos medidas, 26% manifestaron una mejora significativa partiendo de niveles clínicos, 23.5% manifestaron un deterioro significativo y el 20.5% no mostraron cambios significativos, manteniendo niveles clínicos en ambas medidas. Una de las principales conclusiones fue que estar recibiendo o no tratamiento en salud mental resultó ser un factor clave en la evolución de los NNA. Por tanto, resulta crucial establecer sistemas de detección de problemas de salud mental en esta población con el fin de derivar precozmente a tratamientos adecuados.
RESUMO
Several studies have evidenced that children in out-of-home care (OOHC), including foster family care and residential care, reveal high levels of mental health disorders (ranging from 40% to 88%). This study examines the outcomes in mental health reported by key residential workers in a group of children and youth (N = 492) between 8-17 years old who were in residential child care (RCC) in Spain. The research also aims to explore the relationship between mental health outcomes and the provision of mental health services (i.e., receiving any mental health treatment) as well as the influence of child, family, and placement factors. The design of this study includes two measures: a baseline (T1) and a follow-up two years later (T2). The results indicated that 29.9% of young people enjoyed sustained mental health; 26% meaningful improvement in their mental health; 23.5% meaningful deterioration; and the remaining 20.5% showed no meaningful change. One of the main findings was that receiving mental health treatment had a significant impact on mental health outcomes. It is crucial to establish protocols and systematic detection tools to assess mental health and ensure detection and referral to proper treatment. (AU)
La investigación en el ámbito de la protección a la infancia ha destacado la presencia de un alto porcentaje de niños, niñas y adolescentes (NNA) en acogimiento residencial y familiar con trastornos de salud mental (entre el 40% y el 88%). Este estudio tiene como objetivo examinar los cambios experimentados en la salud mental de los NNA durante el proceso de acogida según informan sus educadores de referencia en un grupo de 492 NNA entre 8-17 años que se encontraban en hogares de protección en España. El estudio también tiene como objetivo explorar la relación entre los resultados en salud mental y el tratamiento recibido desde diferentes servicios de salud mental, además de la influencia que puedan ejercer factores del NNA, su familia o el proceso de protección. El diseño del estudio se basa en dos medidas: línea base (T1) y seguimiento dos años después (T2). Los resultados indican que el 29.9% de los NNA mantenía una buena salud mental en las dos medidas, 26% manifestaron una mejora significativa partiendo de niveles clínicos, 23.5% manifestaron un deterioro significativo y el 20.5% no mostraron cambios significativos, manteniendo niveles clínicos en ambas medidas. Una de las principales conclusiones fue que estar recibiendo o no tratamiento en salud mental resultó ser un factor clave en la evolución de los NNA. Por tanto, resulta crucial establecer sistemas de detección de problemas de salud mental en esta población con el fin de derivar precozmente a tratamientos adecuados. (AU)
Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Saúde Mental , Proteção da Criança , Terapêutica , EspanhaRESUMO
This study aims to assess whether participation as a supportive volunteer in equestrian therapy (ET) sessions influences participants' physiological health-related parameters, including physical activity and sleep. Physical activity, measured in steps, and hours of sleep were measured in 10 subjects who participated regularly as volunteers in ET sessions using a triaxial accelerometer which continuously recorded their activity for 30 days. On the one hand, the subjects showed higher physical activity levels on days when they volunteered in ET sessions versus the days they did not. A significant difference and large effect magnitude were found. On the other hand, on the days they attended ET, they slept an average of 30 minutes more, with significant differences and a moderate effect. Thus, participation as a volunteer in ET sessions seems to have a positive influence on physical activity and sleep time, so it should be recommended as an activity to promote healthy habits.
RESUMO
BACKGROUND: We studied the effects of a supervised, structured exercise program in a severe sarcoidosis patient. METHODS: After being clinically stable for two years, a 52-year-old woman (stage IV, American Thoracic Society) who originally had irreversible lung fibrosis, pulmonary arterial hypertension (PAH), mild mitral insufficiency, and atrial dilatation, and was candidate for lung transplant, performed a combined high-intensity interval, high load resistance, and inspiratory muscle training for 4.5 years, and was tested (cardiopulmonary exercise testing and dual X-ray absorptiometry) every six months. RESULTS: Cardiorespiratory fitness (CRF) and maximal pulmonary ventilation increased by 44% and 60%, respectively. Ventilatory efficiency also improved (decrease in the ventilatory equivalent for oxygen by 32% and 14% at the ventilatory threshold and respiratory compensation point, respectively). She improved New York Heart Association (NYHA) class (from III to II), and cardiac alterations as well as PAH reversed so that she was not in need of lung transplantation anymore. Likewise, she suffered no more episodes of hemoptysis. Bone health was overall maintained despite the post-menopausal status and the corticoid treatment. CONCLUSIONS: A long-term combined exercise intervention safely contributed-at least partly-to improve CRF and NYHA class in a patient with severe sarcoidosis, suggesting a potential coadjuvant effect to attenuate clinical manifestations.
Assuntos
Aptidão Cardiorrespiratória , Exercício Físico , Sarcoidose , Teste de Esforço , Tolerância ao Exercício , Feminino , Humanos , Pessoa de Meia-Idade , Consumo de Oxigênio , Sarcoidose/terapiaRESUMO
Dada la actual prevalencia de víctimas de violencia de género y el interés que suscita la comprensión del comportamiento delictivo, esta investigación pretende identificar la existencia de pensamientos distorsionados, así como la falta de atribución de responsabilidad, de una muestra de 129 condenados por violencia de género. Se aplicó la "Escala de atribución de responsabilidad y minimización" y el "Inventario de pensamientos distorsionados sobre la mujer y la violencia". Las principales conclusiones obtenidas manifiestan que los agresores asumen la responsabilidad, puesto que no justifican la agresión, aunque en mayor medida culpabilizan a la víctima. Por otro lado, existe una baja frecuencia de pensamientos distorsionados entre los condenados, si bien tienden a interpretar la violencia como un recurso idóneo para la resolución de conflictos. Se encontró relación entre los pensamientos distorsionados sobre la mujer y la violencia, la falta de atribución de responsabilidad y la minimización del daño. A su vez, los pensamientos distorsionados sobre la mujer y la violencia son predictores de la falta de atribución de responsabilidad
Given the current prevalence of gender-based violence and the interest in criminal behavior, the investigation aims to identify distorted thoughts and the lack of attribution of responsibility in a sample of 129 convicts. The scale of measurement Attribution of Responsibility and Minimization and the inventory Distorted Thoughts about Woman and Violence was applied. The main conclusions show that aggressors assume the responsibility given that they do not justify the aggression although they blame the victim to a greater extent. There is also a low frequency of distorted thoughts among convicts, although they tend to interpret violence as a suitable resource to resolve conflicts. A link was found between distorted thoughts about women and violence, the lack of attribution of responsibility, and the justification of damage. In addition, distorted thoughts about women and violence predict the lack of attribution of responsibility
Assuntos
Humanos , Masculino , Violência Doméstica/psicologia , Violência contra a Mulher , Criminosos/psicologia , Comportamento Criminoso , Prisioneiros/psicologia , Responsabilidade Legal , Agressão/psicologia , PensamentoRESUMO
BACKGROUND: The aim of this paper was to analyze how the rest between interval repetitions in intra-set training (at maximal isometric loads) could affect the ability to repeat maximal contractions in subjects with different levels of performance and different experience in strength development work. METHODS: Twenty subjects were divided randomly into two different groups depending on their sport characteristics: ten subjects were trained in strength development work (Group Strenght--23.1±4.6 years; 172.0±5.3 cm; 79.9±12.1 kg; 2175.6±490.8 N; 46.9±4.9 mL/kg.min), and ten subjects were trained in endurance work (Group Endurance--21.3±4.5 years; 172.4±4.1 cm; 60.0±4.6 kg; 815.5±206.5 N; 67.4±4.9 mL/kg.min). To assess the ability to repeat maximal efforts, 20 repetitions of 5 seconds were performed in a half-squat position, with 1 minute of rest between repetitions. RESULTS: For both groups, four different phases were observed in the Interval Maximal Force test during the 20-repetition assessment: potentiation, maintenance, moderate loss, and significant loss. For the GE, the loss in maximum strength capacity began in the fourth repetition (GS4th: 3.4%, ns, Effect Size: 0.09 vs. GE3th: 1.6%; ns; ES: 0.06) and reached a statistically significant value in the twelfth repetition (GS12th: 12.7%, P=0.03, ES: 0.35 vs. GE7th: 12.5%; P=0.01; ES: 0.49). The number of repetitions at which the strength began to decrease depended on the subject's sport characteristic and performance level. CONCLUSIONS: This study shows how an appropriate intra-set rest inclusion can significantly increase the work performed in every set without changing the muscle contraction characteristics, thus delaying muscle fatigue and maintaining the desired training objective.
Assuntos
Contração Isométrica/fisiologia , Força Muscular/fisiologia , Treinamento Resistido/métodos , Descanso/fisiologia , Humanos , Masculino , Fadiga Muscular/fisiologia , Distribuição Aleatória , Adulto JovemRESUMO
This study analyses the effectiveness of a child abuse prevention programme in an educational context. The proposal for action is based on the use of stories as an instrument of primary prevention. The programme aims to improve a childs capacity to face potentially threatening situations and was applied in 10 primary schools of Extremadura (Spain) to 317 pupils aged 9 and 10 years old. There were 12 sessions whose aim was for the children to gain an awareness of abuse, identify situations of abuse and learn strategies to face them. This was done through the use of tutorials and by linking the programme to the aims of the pupils educational stage. The evaluation of the programme shows that the pupils in the experimental group resolved the situations with increasing skill, confidence and determination; and that they could see more clearly where to look for help in terms of protection measures. The tutors evaluated the programme positively, considering the contents useful for prevention
El estudio analiza la eficacia de un programa de prevención del maltrato infantil en el contexto educativo. La propuesta de actuación parte de la utilización del cuento como instrumento para la prevención primaria. El programa trata de mejorar las capacidades de los niños para enfrentarse a situaciones potencialmente amenazantes. El programa fue aplicado en 10 colegios de Educación Primaria de Extremadura (España), a un conjunto de 317 alumnos de 9 y 10 años. Se estructura en 12 sesiones en las que se trata de que los niños tomen conciencia del maltrato, identifiquen situaciones de abuso y aprendan estrategias de afrontamiento, utilizando para ello la acción tutorial y vinculando el programa a los objetivos de la etapa educativa de los alumnos. La evaluación del programa, demuestra cómo los alumnos del grupo experimental resuelven las situaciones con mayor habilidad, confianza y firmeza, y tienen más claro cuáles son las fuentes de ayuda a las que recurrir como medida de protección. Los tutores valoran positivamente el programa, considerando los contenidos útiles para la prevención
Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Maus-Tratos Infantis/prevenção & controle , Reconhecimento Psicológico , Narração , Serviços de Saúde Escolar , Avaliação de Resultado de Ações Preventivas , Confiança/psicologiaRESUMO
This theoretical study reviews two of the most cited profiles of intimate partner batterers in the scientific literature, paying special attention to the most notable differences between them, as well as to their common criteria. The study also discusses one of the longest standing controversies in various research studies, including the particular overview with respect to Spain: it being the constant yet erroneous reference to the equivalence of psychopathy and antisocial personality disorder. Similarly, special attention is paid to the implications of considering intimate partner batterers as having either a psychopathological or psychopathic profile, while also stressing the specific role played by psychopathy in the intimate partner batterer and, concerning psychopathic intimate partner batterers, such aspects as their specific motives for perpetrating intimate partner violence and the evaluation instruments of this particular profile. Finally, a series of future directives for research concerning psychopathic intimate partner batterers are also pointed out
En este estudio teórico se hace una revisión sobre dos de los perfiles de maltratadores conyugales más citados en la literatura científica, resaltando específicamente las diferencias más notables entre ambos, así como también los criterios en los cuales convergen. Se debate también una de las controversias más prolongadas a través de los diversos estudios de investigación, incluyéndose la concreta panorámica al respecto en España, que es la referente a la constante y errónea equiparación entre psicopatía y trastorno antisocial de la personalidad. Asimismo, se presta especial atención a las implicaciones derivadas de considerar a los maltratadores conyugales bien con un perfil psicopatológico o bien con un perfil psicopático, haciendo especial hincapié en el papel específico que juega la psicopatía en el maltrato conyugal y poniendo de relieve aspectos concernientes a los maltratadores psicópatas tales como sus motivaciones específicas para perpetrar violencia conyugal y los instrumentos de evaluación de este concreto perfil. Finalmente, se señalan una serie de directrices futuras de investigación sobre el perfil del maltratador psicopático
Assuntos
Humanos , Maus-Tratos Conjugais/psicologia , Transtorno da Personalidade Antissocial/epidemiologia , Violência Doméstica/psicologia , Fatores de Risco , Conflito Familiar/psicologiaRESUMO
Las señales biológicas son utilizadas como herramientas para el control y evaluación de las cargas de entrenamiento o los efectos agudos y crónicos que provocan en el organismo del deportista. Este parámetro aún hoy puede ser considerado el más popular de los indicadores de carga empleado por atletas y entrenadores. Cada individuo en condiciones de reposo posee un ritmo natural que, a diferencia de lo que pudiéramos pensar, dista mucho de ser estable. Esto resulta una circunstancia excepcional para su aplicación al entrenamiento deportivo. Estas variaciones es lo que conocemos como Variabilidad del Ritmo Cardiaco. El ritmo cardiaco depende directamente del sistema nervioso autónomo o vegetativo, el cual influye también sobre numerosas funciones del organismo rol y evaluación de las cargas de entrenamiento o los efectos agudos y crónicos que provocan en el organismo del deportista. Su control es dependiente de un elevado número de factores, internos y externos, los cuales varían significativamente durante el ejercicio o en situaciones en las que el organismo altera su situación habitual de funcionamiento. Así, podemos observar como durante el ejercicio el balance simpático-vagal depende de la intensidad y duración del ejercicio. Algunos autores proponen que hasta intensidades de aproximadamente el 50% del VO2max los cambios en la variabilidad del ritmo cardiaco se deben principalmente a la disminución de la descarga parasimpático acompañada de un aumento progresivo de la influencia simpática. Encima de esta intensidad la frecuencia cardiaca y sus oscilaciones pasan a estar prioritariamente influenciados por la actividad simpática. En estas situaciones, las oscilaciones del RC también dependen de dos procesos oscilatorios que actúan como mecanismos de retroalimentación: respiración (arritmia sinorespiratoria); presión arterial (influencia barorrefleja). Estos mecanismos, su evaluación, metodología y herramientas de control, son los aspectos que vamos a analizar en esta revisión (AU)
Biological signals are often used as a tool for the control and evaluation of the training loads or for the evaluation of the acute and chronic effects in the organism of athletes. The Heart Rate is still considered nowadays as the most popular of load indicators among athletes and coaches. Every single individual, in rest conditions, has a natural rhythm but unlike we might think, is far from stable. This is an exceptional circumstance for the application in the athletic training. These variations are known as Heart Rate Variability. The Heart Rate depends directly on autonomic or vegetative nervous system. In turn, it influences on several functions of the organism, training loads evaluation and in the acute and chronic effects produced in the organism of the athlete. The control of this parameter depends on a high number of factors, internals and externals, which vary significantly throughout the exercise time or in situations where the body alters normal operating situation. Thus, we can observe that during exercise the sympathetic -vagal balance is dependent of the intensity and duration of the exercise. Some authors suggest that up 50% VO2max approximately, HRV changes are mainly due to the decreased parasympathetic discharge accompanied by a progressive increase of the sympathetic influence. Above this intensity, HR and its oscillations are primarily influenced by sympathetic activity. In these situations, HR oscillations are also dependents of two oscillatory processes which work as feedback mechanism: breathing (Respiratory sinus arrhythmia) and blood pressure (baroreflex influence). These mechanisms, assessment, methodology and control tools are the issues we will discuss in this review (AU)
Assuntos
Humanos , Frequência Cardíaca/fisiologia , Esportes/fisiologia , Monitorização Fisiológica/instrumentação , Esforço Físico/fisiologiaRESUMO
Da Silva-Grigoletto, ME, de Hoyo, M, Sañudo, B, Corrales, L, and García-Manso, JM. Determining the optimal whole-body vibration dose-response relationship for muscle performance. J Strength Cond Res 25(12): 3326-3333, 2011-The aim of this investigation was twofold: first, to determine the optimal duration of a single whole-body vibration (WBV) exposure (phase 1) and second to find out the ideal number of sets per intervention to maximize muscle performance (phase 2). All participants were young (age: 19.4 ± 1.6 years), healthy, physically active men. In both studies, a 30-Hz frequency and a 4-mm peak-to-peak displacement were used. In phase 1, subjects (n = 30) underwent 3 sets of different durations (30, 60, and 90 seconds), whereas in phase 2, subjects (n = 27) underwent 3 interventions where the duration remained fixed at 60 seconds, and the number of sets performed (3, 6, or 9) was modified. The recovery time between sets was set at 2 minutes. In all interventions, each set consisted of 1 isometric repetition in a squat position with knees flexed at 100°. Before and after each session, jump height (countermovement jump [CMJ] and squat jump [SJ]) and power output in half squat (90° knee flexion) were assessed. In phase 1, an improvement in jump ability and power output was observed after the 30- and 60-second intervention (p < 0.01), whereas the 90 second intervention, participants just experienced a decrease in SJ and CMJ (p < 0.05). When comparing the different protocols, the greatest response was achieved using 60 seconds (p < 0.05), which was therefore considered as the optimal duration to be used in phase 2. In the second phase, improvements in jump ability and power output were found with 3 and 6 sets (p < 0.05), whereas with 9 sets, participants actually experienced a decrease in these variables. Intergroup comparison showed a greater effect for the program of 6 sets (p < 0.05). In conclusion, a WBV intervention consisting of six 60-second sets produces improved muscle performance measured by SJ, CMJ, and power output.
Assuntos
Desempenho Atlético , Exercício Físico/fisiologia , Movimento , Força Muscular , Músculo Esquelético/fisiologia , Vibração , Adolescente , Adulto , Humanos , Contração Isométrica , Masculino , Fatores de Tempo , Adulto JovemRESUMO
The aim of this study was to determine whether the in-game role of players (setter, outside, middle, or opposite player) in elite women's volleyball is significantly related to the characteristics of their service. The sample consisted of 1,300 service deliveries (total serves for all matches) made by players in the 8 teams participating in 2 Final 4 stages of the Indesit European Champions League. The variables recorded were in-game role of the server, service type, speed of delivery, service area, target zone, and effectiveness of delivery. Results showed a significant relation between the server's in-game role and service type (p Assuntos
Voleibol/fisiologia
, Desempenho Atlético/fisiologia
, Desempenho Atlético/estatística & dados numéricos
, Feminino
, Humanos
, Fatores de Tempo
, Voleibol/estatística & dados numéricos
RESUMO
This study sought to determine the effects of hyperbaric pressure on heart rate modulation, by analyzing potential changes in heart rate variability (HRV). Ten divers were exposed to pressures of 1, 2, 3, and 4 atmospheres absolute (ATA). The test was performed in a hyperbaric chamber. Heart rate (HR) was recorded in supine subjects for 10 minutes per atmosphere. HRV was analyzed in the frequency mode (fast-Fourier transform and continuous wavelet transform). Results confirmed bradycardia as pressure increased. The drop in HR attained statistical significance after 2, 3, and 4 ATA. Signal energy (normalized TP values) rose progressively, becoming significant at 2 ATA. High frequency and low frequency displayed similar behavior in both cases. Although frequency band peaks did not yield clear results, continuous wave transform analysis showed that the frequency spectrum tended to shift into the high-frequency range as pressure increased. In summary, increased pressure prompted increased bradycardia, and HRV shifted into high-frequency range.
Assuntos
Mergulho/fisiologia , Sistema de Condução Cardíaco/fisiologia , Frequência Cardíaca/fisiologia , Oxigenoterapia Hiperbárica , Adulto , Análise de Variância , Pressão Atmosférica , Feminino , Humanos , Masculino , Processamento de Sinais Assistido por ComputadorRESUMO
This experiment was designed to assess the acute (Study I) and cumulative response (Study II) of muscle performance to differing recovery times after exposure to whole body vibration (WBV). All subjects (mean age 19.7 +/- 1.9) were healthy and physically active. In both studies, subjects were exposed to a WBV bout of 6 exposures of 60 seconds each, with frequency of 30 Hz and amplitude of 4 mm. In Study I, subjects (n = 30) underwent 3 trials (1 per day) on different days with a 2-day wash-out period between trials; each trial included either a 1, 2, or 3 minutes of recovery between exposures to WBV. All subjects underwent all trials, which were randomly assigned. Jump ability and muscle power were measured before and after each bout. In Study II, subjects (n = 45) underwent 12 sessions of WBV training in 4 weeks (3 bouts/wk). The subjects were randomly assigned to 1 of the following 3 groups: WBV with 1-minute recovery periods between exposures, WBV with 2-minute recovery periods between exposures, or control group. Jump ability, muscle power, and strength were measured before and after each bout. In the acute study (I), recovery times of 1 and 2 minutes enhanced all measured parameters (p < 0.05), with the 2-minute recovery being more effective. In the long-term study (II), however, although both periods also enhanced the measured parameters (p < 0.05), the 1-minute recovery proved more effective because the response was modified by systematic stimulation. In conclusion, 2-minute recovery periods provided the most effective acute enhancement of muscle activation, whereas the 1-minute recovery provided a more effective cumulative enhancement of muscle power and jump ability.
Assuntos
Desempenho Atlético , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Vibração , Adulto , Humanos , Masculino , Adulto JovemRESUMO
Middle and long distance athletics races behave as power-laws when time (or average speed) and distance are related, thus suggesting the presence of critical phenomena. Power-laws as a function of the athlete's position in the all-time world ranking allows us to define a Performance Index that reveals the existence of possible multifractal structures associated to the natural barriers to that the athletes tend in their evolution towards better results and in pursuit of world records. The new theories of self-organized critical phenomena provide an explanation for the power-law and fractal structures in systems at, or near, their critical points. In this paper we analyse the athletic races using these theories and as a result of this study a new variety of interpretations are posited.