A cidade não pode parar: a Maratona do Rio de Janeiro em 2020 na era da pandemia / The city cannot stop: the Rio de Janeiro Marathon in the era of the pandemic / La ville ne peut pas s'arrêter: le Marathon de Rio de Janeiro à l'ère de la pandémie

Neste artigo, iremos apresentar como ocorreu a edição virtual da Maratona do Rio de Janeiro em 2020, ainda sem autorizações sanitárias para a realização de grandes eventos. Para isso, analisaremos o Guia do corredor, apresentado aos corredores na época. A competição é realizada por meio de uso de aplicativos, mas o atleta é estimulado a correr com o slogan "Não correr nunca foi uma opção". Abordamos os conceitos de necrodemografia e necropolítica. Entende-se que a Maratona do Rio pratica uma espécie de necropolíti-ca ao organizar a competição em pleno período pandêmico do Brasil, apesar de valorizar a paisagem da rua em suas plataformas comunicacionais.

In this article, we will present how the virtual edition of the Rio de Janeiro Marathon took place in 2020 in the middle of the pandemic, still without health permits to hold major events. For this, we will analyze the Runner's Guide presented to the runners at the time. The competition is carried out using applications, but the athlete is encouraged to run with the slogan "Not running was never an option". We approach the concepts of necrodemography and necropolitics. It is understood that the Rio Marathon practices a kind of necropolitics when organizing the competition in the middle of the pandemic period in Brazil, despite valuing the street landscape in its communication platforms.

Dans cet article, nous allons vous présenter comment s'est déroulée l'édition virtuelle du Marathon de Rio de Janeiro en 2020, toujours sans autorisations sanitaires pour les grands événements. Pour cela, nous analyserons le Guide du marathonien, présenté aux marathoniens à l'époque. La compétition se déroule à l'aide d'applications, mais l'athlète est encouragé à courir avec le slogan "Ne pas courir n'a jamais été une option". Nous abordons les concepts de nécrodémographie et de nécropolitique. Il est entendu que le Marathon de Rio pratique une sorte de nécropolitique en organisant la compétition en pleine pandémie au Brésil, malgré la valorisation du paysage de rue dans ses plateformes de communication.

Health profile and training habits of 42k marathoners, temuco chile / Perfil de salud y hábitos de entrenamiento de maratonistas 42k, temuco chile / Perfil de saúde e hábitos de treinamento de maratonistas de 42k, temuco chile

ABSTRACT Context: participation of runners in marathons increases each year, making them an attractive population to investigate. In Chile, the characteristics of marathoners in decentralized and emerging races, such as the Temuco Araucanía International Marathon (MITA), are not yet known. Objective: to describe health profile, sociodemographic characteristics, and training habits of the 42K runners enrolled in MITA during the years 2017, 2018 and 2019. Methods: Non-probabilistic convenience sample composed of people over 18 years of age, who signed informed consent. The data were obtained through a survey prepared by the authors, and were analyzed with the statistical program Stata 16.0 to describe the group based on the variables of health profile, sociodemographic characteristics and training habits. Results: 135 adult marathoners were included (n=42-2017, n=45-2018, n=48-2019). The mean age was 39.5±9.1 years and 86.6% were men. Fifteen percent self-reported comorbidities, 96.7% were non-smokers, 80% were normal weight, 65% had a high educational level and 87% were workers. Regarding training habits, it is noteworthy that the frequency was 4.9±1 days per week, with a mean duration of 89±1 minutes per session. Finally, 71.9% of the sample reported doing high intensity training. Conclusions: the MITA 42K runners are generally healthy subjects, nonsmokers and without comorbidities; mostly men, normal weight, middle age, with a high educational level and workers. They present a high frequency of weekly training, with an average duration of 90 minutes per session, this being carried out at high intensity by almost 2/3 of the sample. Knowledge of the health profile and training habits of runners is a first step to responsibly generate guidelines that contribute to strengthening the safe practice of this sport. Level of Evidence IV; Descriptive and Cross-Sectional Study.

RESUMEN Introducción: la participación de corredores en maratones aumenta cada año, convirtiéndolos en una población atractiva de investigar. En Chile, aún no se conocen las características de maratonistas de carreras descentralizadas y emergentes, como la Maratón Internacional Temuco Araucanía (MITA). Objetivo: describir el perfil de salud, las características sociodemográficas y los hábitos de entrenamiento de los corredores de 42K, inscriptos en MITA durante los años 2017, 2018 y 2019. Métodos: Muestra no probabilística por conveniencia mayores de 18 años, que firmaron el término de consentimiento informado. Los datos fueron obtenidos a través de la aplicación de una encuesta de elaboración original, analizados con programa estadístico Stata 16.0 para describir al grupo en función de las variables perfil de salud, sociodemográficas y hábitos de entrenamiento. Resultados: Se incluyeron 135 adultos maratonistas (n=42-2017, n=45-2018, n= 48-2019) La edad promedio fue de 39,5±9,1 años y 86,6% fueron hombres. El 15% auto reportó comorbilidades, 96,7% eran no fumadores; 80% eran normopeso, con un 65% de participantes con nivel educacional alto y 87% trabajadores. En cuanto a los hábitos de entrenamiento, se destaca que la frecuencia es de 4,9±1 días por semana, con una duración media de 89±1 minutos por sesión y finalmente, el 71,9% de la muestra reporta realizar entrenamiento de alta intensidad. Conclusiones: los corredores 42K del MITA son en general sujetos sanos, no fumadores y sin comorbilidades; en su mayoría hombres, normopeso, de edad media, con un nivel educacional alto y trabajadores. Presentan una alta frecuencia de entrenamiento semanal, con una duración promedio de 1:30 minutos por sesión, siendo realizada a alta intensidad casi 2/3 de la muestra. El conocimiento del perfil de salud y hábitos de entrenamiento de los corredores, constituye un primer paso para generar, de forma responsable, lineamientos que contribuyan a fortalecer la práctica segura de este deporte. Nivel de Evidencia IV; Estudio Descriptivo y Transversal.

RESUMO Introdução: a participação de corredores em maratonas aumenta a cada ano, tornando-os uma população atrativa para investigação. No Chile, ainda não são conhecidas as características dos maratonistas em corridas descentralizadas e emergentes, como a Maratona Internacional Temuco Araucanía (MITA). Objetivo: descrever o perfil de saúde, características sociodemográficas e hábitos de treinamento dos corredores de 42K inscritos no MITA durante os anos de 2017, 2018 e 2019. Métodos: Amostra não probabilística de conveniência composta por pessoas maiores de 18 anos, que assinaram o termo de consentimento livre e esclarecido. Os dados foram obtidos por meio de um questionário elaborado pelos autores e foram analisados com o programa estatístico Stata 16.0 para descrever o grupo com base nas variáveis de perfil de saúde, características sociodemográficas e hábitos de treinamento. Resultados: foram incluídos 135 maratonistas adultos (n=42-2017, n=45-2018, n=48-2019). A média de idade foi de 39,5±9,1 anos e 86,6% eram homens. Comorbidades autorreferidas 15%, 96,7% não fumantes, 80% eutróficos, 65% com alta escolaridade e 87% trabalhadores. Em relação aos hábitos de treino, destaca-se que a frequência foi de 4,9±1 dias por semana, com duração média de 89±1 minutos por sessão. Por fim, 71,9% da amostra relatou fazer treinamento de alta intensidade. Conclusões: os corredores do MITA 42K são indivíduos geralmente saudáveis, não fumantes e sem comorbidades; em sua maioria homens, eutróficos, de meia idade, com alto nível educacional e trabalhadores. Apresentam uma elevada frequência de treino semanal, com duração média de 90 minutos por sessão, sendo este realizado em alta intensidade por quase 2/3 da amostra. O conhecimento do perfil de saúde e hábitos de treino dos corredores é um primeiro passo para gerar com responsabilidade orientações que contribuam para o fortalecimento da prática segura deste esporte. Nível de Evidência IV; Estudo Descritivo e Transversal.

Dermatoglyphic Profiles of Competitive Athletes: CrossFit and Ultra-Marathon / Perfiles Dermatoglíficos de Deportistas Competitivos: CrossFit y Ultramaratón

SUMMARY: In the sports field, sports are usually classified according to the predominance of the energy system used during the competition; sports like Crossfit and ultra-marathon could be totally opposite due to the needs of athletes to achieve good places. Due to the above, the objective was established to compare the dermatoglyphic profiles of CrossFit and Ultra-marathon athletes according to the predisposition of the energy systems, aerobic and anaerobic, used in the competitions. Cross-sectional descriptive study, where the dermatoglyphic profile of 21 athletes of national presence (10 crossfit and 11 ultra-marathon runners) was determined, through the Computerized Dermatoglyphic System, brand Salus Dermatoglifia, according to the Cummins and Midlo protocol, which consists of taking the fingerprints of the 10 fingers of the hands. The fingerprint designs of the human being (arch, loop and whorl) and the elements contained in them (nucleus and delta) were analyzed, differences were established through the Analysis of Variance test in the SPSS V.25 statistical package. The results show significant differences between the average scores of the line count of both disciplines (108 and 165), being higher in ultra-marathon runners, associated with greater aerobic resistance. Another significant and relevant finding was the presence of arch-type fingerprints only in CrossFit athletes associated, along with low line count, with strength and power. It is concluded that Crossfit and Ultra-marathon athletes have dissimilar natural physical characteristics, which is why they participate and excel in different sports where they have enhanced their natural physical abilities through training.

En el ámbito deportivo, los deportes suelen clasificarse según el predominio del sistema energético utilizado durante la competición; Deportes como el Crossfit y la ultramaratón podrían ser totalmente opuestos debido a las necesidades de los deportistas de conseguir buenos lugares. Debido a lo anterior, se estableció como objetivo comparar los perfiles dermatoglíficos de atletas de CrossFit y Ultramaratón según la predisposición de los sistemas energéticos, aeróbico y anaeróbico, utilizados en las competencias. Estudio descriptivo transversal, donde se determinó el perfil dermatoglífico de 21 deportistas de presencia nacional (10 crossfit y 11 ultramaratonistas), a través del Sistema Dermatoglífico Computarizado, marca Salus Dermatoglifia, según el protocolo Cummins y Midlo, el cual consta de tomando las huellas dactilares de los 10 dedos de las manos. Se analizaron los diseños dactilares del ser humano (arco, asa y verticilo) y los elementos contenidos en ellos (núcleo y delta), se establecieron diferencias mediante la prueba de Análisis de Varianza en el paquete estadístico SPSS V.25. Los resultados muestran diferencias significativas entre las puntuaciones medias del recuento de líneas de ambas disciplinas (108 y 165), siendo superiores en los corredores de ultramaratón, asociado a una mayor resistencia aeróbica. Otro hallazgo significativo y relevante fue la presencia de huellas dactilares tipo arco sólo en atletas de CrossFit asociadas, junto con un bajo número de líneas, con fuerza y potencia. Se concluye que los atletas de Crossfit y Ultramaratón tienen características físicas naturales disímiles, por lo que participan y destacan en diferentes deportes donde han potenciado sus capacidades físicas naturales a través del entrenamiento.

Effects of physical training on speed and strength in long-distance runners / Efeitos do treinamento físico sobre a velocidade e a força de corredores de longa distância / Efectos del entrenamiento físico en la velocidad y la fuerza de los corredores de fondo

ABSTRACT Introduction Long-distance running is characterized by high speed and long-term endurance. It belongs to the group of long-duration high-speed sports dominated by long-term continuous muscular activity. Objective Explore the effect of physical training in long-distance running on improving speed and strength in athletes. Methods A total of 40 student-athletes at a university in a particular city were selected as research subjects. The experimental grouping was performed by lottery, with 20 in the control group and 20 in the experimental group. Results After the independent sample t-test, the results exhibited P=0.023, less than 0.05, showing that long-distance running physical training is very effective in improving speed and strength; the baseline performance of the experimental group was slightly lower than that of the control group, after training, the mean score of the students in the experimental group elevated compared with the control group. Conclusion Long-distance running physical training can significantly improve speed and strength. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução A corrida de longa distância é caracterizada por um alto grau de combinação de velocidade e resistência a longo prazo. Ela pertence ao grupo de esportes de alta velocidade de longa duração, dominado pela atividade muscular contínua de longo prazo. Objetivo Explorar o efeito do treinamento físico em corrida de longa distância sobre a melhoria da velocidade e da força em seus atletas. Métodos Um total de 40 estudantes de atletismo em uma universidade de uma determinada cidade foram selecionados como objetos de pesquisa, e o agrupamento experimental foi realizado por sorteio, com 20 no grupo de controle e 20 no grupo experimental. Resultados Após o teste t de amostra independente, os resultados exibiram P=0,023, menos de 0,05, mostrando que o treinamento físico de corrida de longa distância é muito eficaz para melhorar a velocidade e a força; o desempenho basal do grupo experimental foi ligeiramente inferior ao do grupo controle, após o treinamento, a pontuação média dos alunos do grupo experimental elevou-se em relação ao grupo controle. Conclusão O treinamento físico de corrida de longa distância pode melhorar significativamente a velocidade e a força. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción Las carreras de larga distancia se caracterizan por un alto grado de combinación de velocidad y resistencia a largo plazo. Pertenece al grupo de deportes de alta velocidad de larga duración en los que predomina la actividad muscular continua de larga duración. Objetivo Explorar el efecto del entrenamiento físico en carreras de fondo sobre la mejora de la velocidad y la fuerza en sus atletas. Métodos Se seleccionó como objeto de investigación a un total de 40 estudiantes de atletismo de una universidad de una ciudad determinada, y el agrupamiento experimental se realizó por sorteo, con 20 en el grupo de control y 20 en el grupo experimental. Resultados Tras la prueba t de muestras independientes, los resultados arrojaron un P=0,023, inferior a 0,05, lo que demuestra que el entrenamiento físico de carrera de larga distancia es muy eficaz para mejorar la velocidad y la fuerza; el rendimiento de partida del grupo experimental fue ligeramente inferior al del grupo de control; tras el entrenamiento, la puntuación media de los alumnos del grupo experimental se elevó en comparación con la del grupo de control. Conclusión El entrenamiento físico de carreras de larga distancia puede mejorar significativamente la velocidad y la fuerza. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Effect of balance training on the physical fitness of marathon runners / Efeito do treinamento de equilíbrio sobre a aptidão física dos maratonistas / Efecto del entrenamiento del equilibrio en la aptitud física de corredores de maratón

ABSTRACT Introduction: As a comprehensive sport, Marathon presents high demands concerning the athletes' comprehensive capacity. Objective: This paper explores to what extent balance skill training can effectively contribute to improving physical fitness for marathon runners. Methods: 120 marathon runners were selected for the pilot experiment. The experimental group received balance training, while the control group underwent no intervention. Results: In the experimental group, the time with eyes closed and feet apart increased from 33.559 ± 15.8570 to 37.203 ± 15.5865s, the time spent in the T-shaped run from 10.144 ± 0.5063s to 9.908 ± 0.5225s, the time spent in the standing long jump from 2.831 ± 0.2648m to 3.058 ± 0.3183m, and the time spent in the T-shaped run from 55.544 ± 2.2581 to 60.845 ± 2.4367 times/min. The total FMS score changed from 14.618 ± 0.9392 to 18.481 ± 1.3909. Shoulder flexibility increased from 2.777 ± 0.4756 to 2.917 ± 0.2994, and active straight knee raise changed from 2.306 ± 0.4692 to 2.803 ± 0.403. Conclusion: Daily balance training can be added to usual marathon training to improve the fitness of its athletes. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: A maratona, enquanto esporte integral, apresenta altas exigências relativas à capacidade plena dos atletas. Objetivo: Este artigo tenta explorar em que medida o treinamento da habilidade de equilíbrio pode efetivamente contribuir para o aprimoramento da aptidão física aos praticantes do esporte de corrida de maratona. Métodos: 120 corredores de maratona foram selecionados para o experimento piloto. O grupo experimental recebeu treinamento de equilíbrio, enquanto o grupo de controle não sofreu qualquer intervenção. Resultados: No grupo experimental, o tempo com olhos fechados e pés separados aumentou de 33,559 ± 15,8570 para 37,203 ± 15,5865s, o tempo gasto na corrida em forma de T de 10,144 ± 0,5063s para 9,908 ± 0,5225s, o tempo gasto no salto em pé em distância de 2,831 ± 0,2648m para 3,058 ± 0,3183m, e o tempo gasto na corrida em forma de T de 55,544 ± 2,2581 para 60,845 ± 2,4367 vezes/min. A pontuação total de FMS mudou de 14,618 ± 0,9392 para 18,481 ± 1,3909. A flexibilidade do ombro aumentou de 2,777 ± 0,4756 para 2,917 ± 0,2994, e o levantamento reto do joelho ativo mudou de 2,306 ± 0,4692 para 2,803 ± 0,403. Conclusão: O treinamento de equilíbrio diário pode ser adicionado ao treino de maratona habitual para melhorar a aptidão física de seus atletas. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: El maratón, como deporte integral, presenta grandes exigencias en cuanto a la capacidad integral de los atletas. Objetivo: Este trabajo pretende explorar hasta qué punto el entrenamiento de las habilidades de equilibrio puede contribuir eficazmente a la mejora de la condición física de los corredores de maratón. Métodos: Se seleccionaron 120 corredores de maratón para el experimento piloto. El grupo experimental recibió entrenamiento de equilibrio, mientras que el grupo de control no se sometió a ninguna intervención. Resultados: En el grupo experimental, el tiempo con los ojos cerrados y los pies separados aumentó de 33,559 ± 15,8570 a 37,203 ± 15,5865s, el tiempo empleado en la carrera en forma de T de 10,144 ± 0,5063s a 9,908 ± 0,5225s, el tiempo empleado en el salto de longitud de pie de 2,831 ± 0,2648m a 3,058 ± 0,3183m, y el tiempo empleado en la carrera en forma de T de 55,544 ± 2,2581 a 60,845 ± 2,4367 veces/min. La puntuación total de FMS pasó de 14,618 ± 0,9392 a 18,481 ± 1,3909. La flexibilidad de los hombros aumentó de 2,777 ± 0,4756 a 2,917 ± 0,2994, y la elevación activa de la rodilla pasó de 2,306 ± 0,4692 a 2,803 ± 0,403. Conclusión: El entrenamiento diario del equilibrio puede añadirse al entrenamiento habitual de maratón para mejorar la forma física de sus atletas. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Relief of sports fatigue after marathon races by pnf stretching / Alívio da fadiga esportiva após corridas de maratona por alongamento pnf / Alivio de la fatiga deportiva tras carreras de maratón mediante estiramientos pnf

ABSTRACT Introduction: Marathon running requires stretching practices to relieve fatigue after exercise. The Proprioceptive Neuromuscular Facilitation (PNF) technique is an advanced stretching technique that allows segmenting of a specific muscle group for simultaneous stretching and strengthening. Objective: This paper explores the effect of PNF stretching exercise on relieving sports fatigue after marathon races. Methods: In this paper, 160 marathon runners were selected for the experiment, and randomly divided into experimental and control groups. The experimental group performed the PNF stretching exercise, while the control group remained with traditional stretching without any new intervention. Fatigue was assessed according to the heart rate, collected before, during, and after the experiment. Results: After nine weeks of PNF stretching training, the heart rate in the experimental group changed from 65.35 to 62.46 in the morning; during training, the group's heart rate changed from 180.79 to 173.04; after recovery, the first group's heart rate changed from 82.88 to 81.88. In the control group, the heart rate of the group also showed changes from 65.29 to 68.86 in the morning; during training, it changed from 180.7 to 175.49; and after recovery, from 86.23 to 88.4. Conclusion: PNF stretching exercise has a positive effect on relieving sports fatigue after marathon races. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: A corrida de maratona requer práticas de alongamento para aliviar a fadiga após o exercício. A técnica de Facilitação Neuromuscular Proprioceptiva (PNF) é uma técnica avançada de alongamento que permite segmentar um grupo muscular específico, para alongamento e fortalecimento simultâneos. Objetivo: Este artigo tenta explorar o efeito do exercício de alongamento PNF no alívio da fadiga esportiva após corridas de maratona. Métodos: Neste artigo, 160 corredores de maratona foram selecionados para o experimento, divididos aleatoriamente em grupos experimental e controle. O grupo experimental fez o exercício de alongamento PNF, enquanto o grupo de controle permaneceu com o alongamento tradicional, sem qualquer nova intervenção. A fadiga foi avaliada segundo a frequência cardíaca, coletada antes, durante e após o experimento. Resultados: Após nove semanas de treinamento de alongamento PNF, a frequência cardíaca no grupo experimental alterou-se de 65,35 para 62,46 pela manhã; durante o treinamento, a frequência cardíaca do grupo alterou-se de 180,79 para 173,04; após a recuperação, a frequência cardíaca do primeiro grupo alterou-se de 82,88 para 81,88. No grupo de controle, a frequência cardíaca do grupo também exibiu alterações de 65,29 para 68,86 pela manhã; Durante o treinamento, mudou de 180,7 para 175,49; e após a recuperação, de 86,23 para 88,4. Conclusão: O exercício de alongamento PNF tem um efeito positivo no alívio da fadiga esportiva após corridas de maratona. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: Las carreras de maratón requieren prácticas de estiramiento para aliviar la fatiga tras el ejercicio. La técnica de Facilitación Neuromuscular Propioceptiva (PNF) es una técnica avanzada de estiramiento que permite segmentar un grupo muscular específico, para estirar y fortalecer simultáneamente. Objetivo: Este trabajo pretende explorar el efecto del ejercicio de estiramiento PNF en el alivio de la fatiga deportiva tras carreras de maratón. Métodos: En este trabajo, se seleccionaron 160 corredores de maratón para el experimento, divididos aleatoriamente en grupos experimental y de control. El grupo experimental realizó el ejercicio de estiramiento PNF, mientras que el grupo de control permaneció con el estiramiento tradicional, sin ninguna nueva intervención. La fatiga se evaluó en función de la frecuencia cardiaca, recogida antes, durante y después del experimento. Resultados: Tras nueve semanas de entrenamiento de estiramientos PNF, la frecuencia cardiaca del grupo experimental pasó de 65,35 a 62,46 por la mañana; durante el entrenamiento, la frecuencia cardiaca del grupo pasó de 180,79 a 173,04; tras la recuperación, la frecuencia cardiaca del primer grupo pasó de 82,88 a 81,88. En el grupo de control, la frecuencia cardiaca del grupo también mostró cambios de 65,29 a 68,86 por la mañana; durante el entrenamiento, cambió de 180,7 a 175,49; y tras la recuperación, de 86,23 a 88,4. Conclusión: El ejercicio de estiramiento PNF tiene un efecto positivo en el alivio de la fatiga deportiva después de correr un maratón. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Effects of resistance training on exercise tolerance in marathon runners / Efeitos do treinamento de resistência sobre a tolerância ao exercício em corredores de maratona / Efectos del entrenamiento de resistencia sobre la tolerancia al ejercicio en corredores de maratón

ABSTRACT Introduction: A high index of exercise tolerance is fundamental for marathon runners, indicating a good capacity to perform the exercises considering their maximum duration and workload. Objective: Evaluate the effects of resistance training with different loads on exercise tolerance of marathon runners. Methods: 120 professional long-distance runners were selected as volunteers for the experiment. Divided into experimental groups A, B and Control, the intervention had a 9-week period. The experimental groups A and B received resistance training with different loads, while the Control group did not undergo training intervention. Results: Upper limb muscle mass increased from 3.38 ± 0.18 to 3.75 ± 0.37 in group A; from 3.40 ± 0.15 to 3.66 ± 0.31 in group B; peak biceps brachii moment increased from 53.60 ± 6.27 to 62.97 ± 8.87 in group A; from 53.67 ± 5.68 to 58.48 ± 6.16 in group B; from 5. 37 ± 2.16 to 5.73 ± 2.67 in group A; from 7.21 ± 2.62 to 6.76 ± 4.36 in group B; and from 154.86 ± 19.69 to 108.30 ± 31.75 in group A; group B presented a reduction from 156.97 ± 46.13 to 116.45 ± 39.09, and the data from the control group did not change significantly. Conclusion: Resistance training with different loads in daily training can effectively improve the endurance of long-distance runners. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: Um índice elevado de tolerância ao exercício é fundamental para corredores de maratona, sinalizando uma boa capacidade para a realização dos exercícios considerando sua duração máxima e carga de trabalho. Objetivo: Avaliar os efeitos do treinamento de resistência com distintas cargas sobre a tolerância ao exercício dos corredores de maratona. Métodos: Foram selecionados 120 corredores profissionais de longa distância como voluntários para o experimento. Divididos em grupo experimental A, B e Controle, a intervenção teve um período de 9 semanas. Os grupos experimentais A e B receberam treinamento de resistência com cargas diferentes, enquanto o grupo Controle não sofreu intervenção de treinamento. Resultados: A massa muscular dos membros superiores elevou-se de 3,38 ± 0,18 para 3,75 ± 0,37 no grupo A; de 3,40 ± 0,15 para 3,66 ± 0,31 no grupo B; o momento de pico do bíceps braquial aumentou de 53,60 ± 6,27 para 62,97 ± 8,87 no grupo A; de 53,67 ± 5,68 para 58,48 ± 6,16 no grupo B; de 5. 37 ± 2,16 para 5,73 ± 2,67 no grupo A; de 7,21 ± 2,62 para 6,76 ± 4,36 no grupo B; e de 154,86 ± 19,69 para 108,30 ± 31,75 no grupo A; o grupo B apresentou redução de 156,97 ± 46,13 para 116,45 ± 39,09, e os dados do grupo de controle não sofreram alterações significativas. Conclusão: O treinamento de resistência com diferentes cargas no treinamento diário pode efetivamente melhorar a resistência dos corredores de longa distância. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: Un alto índice de tolerancia al ejercicio es fundamental para los corredores de maratón, indicando una buena capacidad para realizar los ejercicios, considerando su máxima duración y carga de trabajo. Objetivo: Evaluar los efectos del entrenamiento de resistencia con diferentes cargas sobre la tolerancia al ejercicio de corredores de maratón. Métodos: 120 corredores profesionales de larga distancia fueron seleccionados como voluntarios para el experimento. Divididos en los grupos experimentales A, B y Control, la intervención tuvo una duración de 9 semanas. Los grupos experimentales A y B recibieron entrenamiento de resistencia con diferentes cargas, mientras que el grupo Control no se sometió a intervención de entrenamiento. Resultados: La masa muscular del miembro superior aumentó de 3,38 ± 0,18 a 3,75 ± 0,37 en el grupo A; de 3,40 ± 0,15 a 3,66 ± 0,31 en el grupo B; el momento máximo del bíceps braquial aumentó de 53,60 ± 6,27 a 62,97 ± 8,87 en el grupo A; de 53,67 ± 5,68 a 58,48 ± 6,16 en el grupo B; de 5. 37 ± 2,16 a 5,73 ± 2,67 en el grupo A; de 7,21 ± 2,62 a 6,76 ± 4,36 en el grupo B; y de 154,86 ± 19,69 a 108,30 ± 31,75 en el grupo A; el grupo B presentó una reducción de 156,97 ± 46,13 a 116,45 ± 39,09, y los datos del grupo control no sufrieron cambios significativos. Conclusión: El entrenamiento de resistencia con diferentes cargas en el entrenamiento diario puede mejorar eficazmente la resistencia de los corredores de fondo. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Impacts of core training on athletes' performance in long-distance running / Impactos do treino do core no desempenho de atletas na corrida de longa distância / Efectos del entrenamiento del core en el rendimiento de atletas en carreras de larga distancia

ABSTRACT Introduction: Long-distance runners cannot achieve training effects by relying only on speed endurance training. Core training exercises significantly improve stability, allowing learning of techniques with superior movement efficiency. Several factors that affect the development of athletes' special skills are considered, highlighting their main strengths and working on intermediate characteristics. Objective: Verify the impacts of core training on athletes' performance in long-distance running. Methods: This paper had 18 middle-distance runners as volunteers for the research. The athletes' physical conditioning and athletic performance before and after training were examined. Statistical analyses on the indicators of the experimental and control groups were analyzed based on the T-test. Results: There were significant differences in endurance, core muscle elasticity, core strength, explosive power, and stability (P<0.05); the results showed that the differences in core stability between the left and right legs of the experimental group were significant (P<0.05). Conclusion: Core strength exercise is more conducive to exercising a myocardial group in medium and long-distance exercise than conventional strength exercise. Core strength exercises can compensate for a lack of regular strength. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: Corredores de longa distância não podem alcançar efeitos de treinamento apenas contando com os treinos de resistência de velocidade. Os exercícios de treino do core melhoram significativamente a estabilidade que permite um aprendizado da técnica com eficiência superior do movimento. Para isso, são considerados vários fatores que afetam o desenvolvimento das habilidades especiais dos atletas, destacando seus principais pontos fortes e trabalhando nas características intermediárias. Objetivo: Verificar os impactos do treino do core no desempenho de atletas na corrida de longa distância. Métodos: Este artigo teve a participação de 18 corredores de média distância como voluntários para a pesquisa. Foi examinado o condicionamento físico dos atletas e o desempenho atlético antes e depois dos treinos. As análises estatísticas nos indicadores dos grupos experimentais e de controle foram analisadas com base no teste-T. Resultados: Houve diferenças significativas na resistência, elasticidade muscular essencial, força do core, potência explosiva e estabilidade (P<0,05); os resultados mostraram que as diferenças na estabilidade do núcleo entre as pernas esquerda e direita do grupo experimental foram significativas (P<0,05). Conclusão: O exercício de força do core é mais propício ao exercício de um grupo miocárdio em exercícios de média e longa distância do que o exercício de força convencional. Exercícios de força do core podem compensar a falta de força regular. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: Los corredores de larga distancia no pueden conseguir los efectos del entrenamiento basándose únicamente en el entrenamiento de la velocidad y la resistencia. Los ejercicios de entrenamiento del core mejoran significativamente la estabilidad que permite un aprendizaje de la técnica con una eficiencia de movimiento superior. Para ello, se tienen en cuenta varios factores que afectan al desarrollo de las capacidades especiales de los deportistas, destacando sus principales puntos fuertes y trabajando sobre las características intermedias. Objetivo: Verificar los impactos del entrenamiento del core en el rendimiento de los atletas en carreras de larga distancia. Métodos: Este artículo contó con la participación de 18 corredores de media distancia como voluntarios para la investigación. Se examinó la condición física y el rendimiento deportivo de los atletas antes y después del entrenamiento. Los análisis estadísticos en los indicadores de los grupos experimental y de control se analizaron a partir de la prueba T. Resultados: Hubo diferencias significativas en la resistencia, la elasticidad de los músculos centrales, la fuerza central, la potencia explosiva y la estabilidad (P<0,05); los resultados mostraron que las diferencias en la estabilidad central entre las piernas izquierda y derecha del grupo experimental eran significativas (P<0,05). Conclusión: El ejercicio de fuerza del núcleo favorece más el ejercicio del grupo miocárdico en el ejercicio de media y larga distancia que el ejercicio de fuerza convencional. Los ejercicios de fuerza del core pueden compensar la falta de fuerza habitual. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Evaluation of left ventricular structure and systolic function in amateur marathoners by three-dimensional speckle tracking echocardiography / 中华超声影像学杂志

Objective:To assess the left ventricular(LV) structure and systolic function in amateur marathon runners using real-time three-dimensional speckle tracking echocardiography(3D-STE) and analyze its correlation with the running volume.Methods:A total of 84 amateur marathon runners were recruited between January 2019 and October 2021 in Hangzhou and were divided into short-term (ST) group(≤6 months) and more extended-term(MET) group(>6 months–2 years) based on their time of participating in the marathon. Thirty-nine healthy volunteers were enrolled from the Affiliated Hospital of Hangzhou Normal University during the same period as a control group. The running volume of ST and MET runners were recorded, LV end-diastolic volume(EDV), end-systolic volume(ESV), LV mass(LVM), LV ejection fraction(LVEF), LV global longitudinal strain(GLS), global circumferential strain(GCS), global radial strain(GRS), global area strain (GAS), twist, and torsion were measured by conventional echocardiography and 3D-STE. The differences of those parameters among the three groups were compared. The correlation between 3D-STE parameters and the running volume was further analyzed.Results:In ST amateur marathon runners, LV EDV was higher compared with controls( P<0.05). Compared with ST and control groups, LV EDV, ESV, and LVM of MET runners were increased(all P<0.05). In addition, compared with control group, GLS of MET runners was increased( P<0.05). The LVEF, GCS, GRS, GAS, twist, and torsion showed no statistically significant differences among the three groups(all P>0.05). In amateur marathon runners LV EDV, ESV, LVM had statistically significant positive correlations with an average weekly running volume and total running volume (all P<0.01). Multivariate linear regression analysis showed that the total running volume was an independent correlation factor in LV EDV of amateur marathon runners (β=0.618, P<0.01). Conclusions:Amateur marathon runners participating in a short term marathon mainly show an increase in LV EDV, the longitudinal systolic function of the LV can be enhanced in the early stage of the marathon.

Effectiveness of a Conditioning Program on Amateur Female Marathon Runners.

There is a sudden rise in the participation of middle-aged women in marathons across India without proper knowledge about how to prepare for these marathons. This leads to rise in injuries in them like low back pain, knee pain, stress fractures, urinary incontinence etc., some of which can easily be avoided. There is a need to find out a suitable conditioning program for these participants that will target problems affecting this age group and gender specifically. The objective of this study was to determine the effect of conditioning program on post run physical functioning in female amateur marathon runners. Pain Assessment, DOMS, Modified Borg Scale were used for assessing the individuals. METHODSIn this comparative study, 52 amateur female marathon runners, were randomly allocated into two groups with 26 runners in each group. We evaluated pain and exertion using pain assessment and Borg Scale. Occurrence of incontinence was assessed by asking a simple ‘yes’ or ‘no’ question. Delayed onset muscle soreness (DOMS) was assessed using pain pressure threshold (PPT) 24 hrs. post run. RESULTSThere was a significant effect of the conditioning program on these female runners compared to administration of no conditioning at all. There was a reduction of pain in all the components of the pain scale (p= <0.001). Exertion of the trained runners was also less (p= <0.001) as well as in the occurrence of incontinence (p= <0.0430). PPT was also substantially increased in them (p= <0.001). CONCLUSIONSThe conditioning program administered to amateur female marathon runners was effective in reducing their risk of injuries and problems related to women’s health that occur while running a marathon.

Speed and heart rate variation during marathon running in a hot environment / Variación de la velocidad y la frecuencia cardiaca durante un maratón en un ambiente caluroso

Abstract The purpose of the study was to analyze the variation of running speed and heart rate in amateur runners during a marathon in a hot environment. Eighteen runners (weight: 65.2 ± 12.21 kg, height: 168.4 ± 10.6 cm, VO2max: 52.9 ± 7.1 ml/kg/min) took part of a beach-side marathon (42195 m) under a temperature of 27.8 ± 3.52 ºC and at 0-80 m altitude. Pearson's correlation showed a significant linear relationship between the increase in thermal stress index (WGBT) and the speed variation (r= 0.168, p= 0.049). In this respect, the total duration of the race revealed a direct relationship with speed (r= 0.675, p= 0.003) and heart rate (r= 0.631, p= 0.007) variation. Multiple regressions analysis showed that 61.6% of the final race time was explained by the speed variation in the 26 to 30 km course section (r 2 = 0.61; F= 26.17; p< 0.001) and 37% by the heart rate variation in the 31 to 35 km section (r 2 = 0.37; F= 10.38; p< 0.001). In conclusion, an increase in the environmental temperature provoked a decrease in running pacing, with a stronger effect in the second half of the race. Therefore, coaches should take these aspects into account in training and strategies to mitigate the impact of these conditions on the physical and physiological performance of amateur runners.

Resumo O presente estudo teve como objetivo analisar a variação da velocidade da corrida e a frequência cardíaca em corredores amadores durante uma maratona em um ambiente de alto índice térmico. Dezoito corredores amadores (peso: 65,2 ± 12,21 kg, altura: 168,4 ± 10,6 cm, VO2max: 52,9 ± 7,1 ml/kg/min) correram uma maratona (42195 m) em proximidade ao mar, sob um índice térmico de 27,8 ± 3,52 ºC e com percurso de 0-80 metros acima do nível do mar. O teste de Pearson apresentou uma correlação significativa entre o aumento do índice de estresse térmico (IBUTG) e a variação da velocidade (r= 0,168, p= 0,049). Neste sentido, a duração total da corrida apresentou uma relação direta com a velocidade (r= 0,675, p= 0,003) e a variação da frequência cardíaca (r= 0,631, p= 0,007). O tempo final da corrida se interpretou em 61,6% e 37% pela variação da velocidade de 26 a 30 km (r 2 = 0,61; F= 26,17; p< 0,001) e pela variabilidade da frequência cardíaca no lapso de 31 a 35 km (r 2 = 0,37; F= 10,38; p< 0,001), respectivamente. Em suma, o índice térmico provoca uma diminuição no ritmo da velocidade, sendo esse efeito maior na segunda metade da corrida. Devido a isso, os preparadores devem planejar treinamentos e estratégias para mitigar o impacto dessas condições no desempenho físico e fisiológico dos corredores amadores.

Resumen El objetivo del presente estudio fue analizar la variación de la velocidad de carrera y la frecuencia cardíaca en corredores aficionados durante un maratón en un entorno de alto índice térmico. Dieciocho corredores aficionados (peso: 65.2 ± 12.21 kg, altura: 168.4 ± 10.6 cm, VO2max: 52.9 ± 7.1 ml/kg/min) corrieron un maratón (42 195 m) en cercanía al mar bajo un índice térmico de 27.8 ± 3.52ºC y con recorrido de 0-80 m.s.n.m. La prueba de Pearson mostró una correlación significativa entre el aumento del índice de estrés termal (TGBH) y la variación de la velocidad (r = 0.168, p = 0.049). En este sentido, la duración total de la carrera presentó una relación directa con la velocidad (r = 0.675, p = 0.003) y la variación de la frecuencia cardíaca (r= 0.631, p = 0.007). El tiempo final de carrera se explicó en un 61.6% y 37% por la variación de la velocidad de 26 a 30 km (r 2 = 0.61; F = 26.17; p < 0.001) y por la variabilidad de la frecuencia cardíaca en el lapso de 31 a 35 km (r 2 = 0.37; F= 10.38; p < 0.001) respectivamente. En conclusión, el índice térmico provoca una disminución en el ritmo de la velocidad, este efecto mayor en la segunda mitad de la carrera. Por lo anterior, entrenadores deben planificar entrenamientos y estrategias para mitigar el impacto de estas condiciones en el desempeño físico y fisiológico de los corredores amateur.

Prevalence Of Shin Splint In Recreational Marathon Runner

Background: It is essential to find out the presence of shin splint in recreational marathon runners to prevent the injury from causing more damage. This study was conducted to identify shin splint in recreational marathon runners in Krishna Hospital, Karad. This study was designed to provide meaningful insight into the cause of shin splint in recreational marathon runners. Objectives of the study were to find out the impact of shin splint in recreational marathon runners and to assess the severity of shin splint in recreational marathon runners of age group 20-30 years both males and females in Krishna Hospital, Karad. Material and Methods: 190 recreational marathon runners who fit in the criteria were given Runner’s Questionnaire and were asked to fill it. Result: There was marked significance pain was present during(p=0.04) and running throughout(p<0.0001) in recreational marathon runners. Conclusion: It was concluded from the present study that there is a prevalence of shin splint in marathon runners. Shin splint was found more in females (55.3%)than in males (44.7%). Based on the duration of pain and shoe surface was found to be more prevalent to cause shin splint in marathon runners.

MRI of foot pain in amateur marathoners and analysis of related factors / 中华放射学杂志

Objective@#To study the MRI manifestations of foot injuries in amateur marathoners and the diagnostic value of MRI for foot injuries.@*Methods@#Forty-eight amateur marathoners were prospectively recruited from October 2018 to March 2019. Participants were grouped according to the FASS criteria. All participants underwent bilateral foot MRI examinations. The MRI features of foot in amateur marathoners with and without foot pain were analyzed.The association with gender, age, time to participate in marathon, amount of running per week, number of times to complete the whole marathon and the symptoms of foot pain was studied.@*Results@#There were 28 sides in FASS in grade 0, including 8 males and 20 females, 8 hydrocele of the first metatarsophalangeal joint, 6 edema of bone marrow, 4 edema of soft tissue, 4 hydrocele of tendon sheath, and 6 without abnormal manifestations of MRI. There were 68 sides in FASS grade 1, including 42 males and 26 females, 38 Achilles tendinitis, 14 plantar fasciitis, 12 Achilles tendon bursitis and 4 posterior ankle impingement syndrome. The incidence of foot pain in amateur marathoners was related to gender (OR=1.060, P=0.043), unrelated to age (OR=0.248, P=0.078), number of marathons completed (OR=1.006, P=0.956), time to participate in marathon (OR=1.008, P=0.944), amount of running per week (OR=0.971, P=0.407).@*Conclusion@#Among amateur marathon runners, the foot pain is mainly caused by Achilles tendon and plantar fascia, while those without foot pain are mainly characterized by joint effusion, tendon sheath effusion and bone marrow edema. Gender is the only factor affecting the incidence of foot pain in amateur marathoners. MRI examination is an effective method to determine foot injury and has important clinical application value in the diagnosis and treatment of foot injury.

The value of diffusion tensor imaging in the quantitative study of thigh muscles in amateur marathon runners / 中华放射学杂志

Objective@#To test the differences in diffusion properties-namely fractional anisotropy (FA) and apparent diffusion coefficient(ADC)-between amateur marathon runners and healthy volunteers′ thigh muscles using diffusion tensor imaging (DTI) at rest.@*Methods@#Thirty amateur marathon runners(Group A) and 20 healthy volunteers (Group B) were recruited. All were males and their age was between 28 to 53 years. All subjects underwent both thigh DTI examination. DTI parameters FA and ADC were evaluated in thigh muscles(rectus femoris, vastus lateralis, vastus intermedius, vastus medialis, adductor longus, adductor magnus, biceps femoris long head, semitendinosus and semimembranosus)in all subjects. We tested the differences in diffusion properties between GroupA and B using independent sample t test.@*Results@#The average FA value of the thigh muscles measured in Group A was (0.24±0.03), which was significantly lower than that in Group B=(0.27±0.03)(t=5.164,P<0.01). The average ADC value of the thigh muscles measured in Group A was (1.74±0.10)×10-3mm2/s, which was significantly higher than that in Group B=(1.70±0.09)×10-3mm2/s (t=2.060,P<0.05). The FA value of Group A was lower than that of Group B in the rectus femoris, vastus lateralis, vastus medialis, biceps femoris long head, semitendinosus and semimembranosus (P<0.05). The ADC value of Group A was higher than that of Group B in the vastus intermedius, vastus medialis and biceps femoris long head (P<0.05).@*Conclusions@#In the absence of positive findings from conventional MRI, DTI technique can non-invasively assess the subtle changes in the bilateral thigh muscles of amateur marathon runners at rest in the early stage of microscopic molecular level, providing important imaging evidence for early changes in skeletal muscle caused by marathon.

MRI features and related factors of ankle injury in amateur marathoners / 中华放射学杂志

Objective@#To explore the factors, characteristics and imaging manifestations of ankle joint injury in amateur marathoners (no formal training and no marathon career).@*Methods@#From December 2018 to March 2019, the amateur marathon runners in Guangdong Zhuhai had been recruited as research subjects according to the study inclusion and exclusion criteria. The questionnaires were used to collect relevant data, and the subjects underwent MRI scans of the ankle joint. The ankle joint special phased array coils were used to perform fast spin echo sequence (TSE) coronal T1WI and proton density-weighted fat-suppression sequence (PDWI-FS). Axial, coronal and sagittal scans, three-dimensional-double echo steady-state sequence (3D-DESS) and three-dimensional variable flip angle fast spin echo sequence (3D-SPACE) scans were also acquired. The results of the examination were independently analyzed by two radiologists (5 and 17 years of work experience, respectively) on the ligament, tendon, bone marrow and ankle joint injuries. When they had inconsistent views, the diagnosis provided by the third radiologist (27 years of work experience) was considered a final diagnosis. The relationship between ankle injury and different running postures, the number of participating in marathons and training intensity was analyzed, and the independent sample χ2 was used for statistical analysis. The consistency of two radiologists was tested by Kappa test.@*Results@#According to the inclusion and exclusion criteria, 39 subjects were included, with 64 ankles totally, 35 right ankles and 29 left ankles. MRI showed that (1) Ligament injuries: 28 ankles were anterior talofibular ligament injuriy;50 ankles were posterior talofibular ligament injury; 60 ankles the calcaneofibular ligament injuries and 54 ankles were deltoid ligament injuries, without complete injury. (2) Tendon sheath effusion and injuries: peritendinous effusion was common, with 47 flexor hallucis longus tenosynovitis, 49 posterior tibialis tenosynovitis, 37 flexor digitorum longus tenosynovitis, 7 peroneus longus tenosynovitis and 5 peroneus brevis tenosynovitis. (3) Synovitis effusion: 43 posterior ankle synovitis and local effusion. (4) Others: cartilage injury in 2 ankles, bone marrow edema in 8 ankles, and among them stress fracture in 2 ankles. The two radiologists had good consistency with the Kappa value of 0.91. Regarding the running posture, the incidence of ligaments injuries was obviously higher in those who landed on the hind foot than in those landed on front and middle foot,and the difference was statistically significant(P=0.013, χ2 value was 6.191).The incidence of tendon injuries was higher in those who landed on the front middle foot than in those landed on the hind foot, and the difference was statistically significant (P=0.029, χ2 value was 4.775). Those with larger training (training running ≥300 km/month) had significant ankle injury (P=0.005, χ2 value was 7.844).@*Conclusion@#The MRI features of ankle joint injuries in amateur marathon volunteers are related to different running postures and training intensity.

Quantitative T2* MRI study of knee articular cartilage of amateur marathon runners after running a half marathon / 中华放射学杂志

Objective@#To study the effects of half marathon loading on the T2* mapping assessment of knee joint cartilage.@*Methods@#Twenty male amateur marathon runners with more than three years of running age were enrolled. The T1WI, PDWI, 3D-DESS, and T2* mapping were performed on right knee joint before and after the half marathon within 3h and after a period of approximately 1 week. Cartilage was divided into 6 regions: medial and lateral femoral cartilage, medial and lateral tibial cartilage and patella and trochlea cartilage. Femoral cartilage was partitioned into central weight-bearing regions, posterior cartilage nonweight-bearing regions with the posterior boundary of the meniscus as the dividing mark. All cartilage was further divided into deep and superficial layers according to the thickness 1/2, and the ROI was delineated to obtain the T2* value of the corresponding area. One-way repeated measures analysis was performed to test the difference of T2* values pre- and post-marathon. LSD tests were used to estimate the different influences of physiological activities on each articular cartilage area.@*Results@#All cartilage areas of the knee joint did not show cartilage injury during the examination. The differences in the global T2* values of the superficial layers of the knee cartilage before and after the half-marathon marathon were statistically significant (t=5.145, P<0.05), but the global T2* value of the deep region were not (t=1.864, P>0.05). After a week, the T2* values of all cartilage areas were not statistically different from those before running (t=1.062, 0.309; P>0.05).@*Conclusion@#After a single half marathon, the changes of knee cartilage composition in male amateur marathon runners are reversible. In the absence of positive findings in conventional MRI, T2* mapping can indirectly reflect changes in biochemical composition of the articular cartilage during exercise.

MRI of foot pain in amateur marathoners and analysis of related factors / 中华放射学杂志

Objective To study the MRI manifestations of foot injuries in amateur marathoners and the diagnostic value of MRI for foot injuries. Methods Forty?eight amateur marathoners were prospectively recruited from October 2018 to March 2019. Participants were grouped according to the FASS criteria. All participants underwent bilateral foot MRI examinations. The MRI features of foot in amateur marathoners with and without foot pain were analyzed.The association with gender, age, time to participate in marathon, amount of running per week, number of times to complete the whole marathon and the symptoms of foot pain was studied. Results There were 28 sides in FASS in grade 0, including 8 males and 20 females, 8 hydrocele of the first metatarsophalangeal joint, 6 edema of bone marrow, 4 edema of soft tissue, 4 hydrocele of tendon sheath, and 6 without abnormal manifestations of MRI. There were 68 sides in FASS grade 1, including 42 males and 26 females, 38 Achilles tendinitis, 14 plantar fasciitis, 12 Achilles tendon bursitis and 4 posterior ankle impingement syndrome. The incidence of foot pain in amateur marathoners was related to gender(OR=1.060, P=0.043), unrelated to age(OR=0.248, P=0.078), number of marathons completed(OR=1.006, P=0.956), time to participate in marathon(OR=1.008,P=0.944), amount of running per week (OR=0.971,P=0.407). Conclusion Among amateur marathon runners, the foot pain is mainly caused by Achilles tendon and plantar fascia, while those without foot pain are mainly characterized by joint effusion, tendon sheath effusion and bone marrow edema. Gender is the only factor affecting the incidence of foot pain in amateur marathoners. MRI examination is an effective method to determine foot injury and has important clinical application value in the diagnosis and treatment of foot injury.

The value of diffusion tensor imaging in the quantitative study of thigh muscles in amateur marathon runners / 中华放射学杂志

Objective To test the differences in diffusion properties?namely fractional anisotropy (FA) and apparent diffusion coefficient(ADC)?between amateur marathon runners and healthy volunteers′thigh muscles using diffusion tensor imaging (DTI) at rest. Methods Thirty amateur marathon runners(Group A) and 20 healthy volunteers (Group B) were recruited. All were males and their age was between 28 to 53 years. All subjects underwent both thigh DTI examination. DTI parameters FA and ADC were evaluated in thigh muscles(rectus femoris, vastus lateralis, vastus intermedius, vastus medialis, adductor longus, adductor magnus, biceps femoris long head, semitendinosus and semimembranosus)in all subjects. We tested the differences in diffusion properties between GroupA and B using independent sample t test. Results The average FA value of the thigh muscles measured in Group A was (0.24 ± 0.03), which was significantly lower than that in Group B=(0.27±0.03)(t=5.164,P<0.01). The average ADC value of the thigh muscles measured in Group A was (1.74±0.10)×10?3mm2/s, which was significantly higher than that in Group B=(1.70±0.09)×10?3mm2/s (t=2.060,P<0.05). The FA value of Group A was lower than that of Group B in the rectus femoris, vastus lateralis, vastus medialis, biceps femoris long head, semitendinosus and semimembranosus (P<0.05). The ADC value of Group A was higher than that of Group B in the vastus intermedius, vastus medialis and biceps femoris long head(P<0.05). Conclusions In the absence of positive findings from conventional MRI, DTI technique can non?invasively assess the subtle changes in the bilateral thigh muscles of amateur marathon runners at rest in the early stage of microscopic molecular level, providing important imaging evidence for early changes in skeletal muscle caused by marathon.

MRI features and related factors of ankle injury in amateur marathoners / 中华放射学杂志

Objective To explore the factors, characteristics and imaging manifestations of ankle joint injury in amateur marathoners (no formal training and no marathon career). Methods From December 2018 to March 2019, the amateur marathon runners in Guangdong Zhuhai had been recruited as research subjects according to the study inclusion and exclusion criteria. The questionnaires were used to collect relevant data, and the subjects underwent MRI scans of the ankle joint. The ankle joint special phased array coils were used to perform fast spin echo sequence (TSE) coronal T1WI and proton density?weighted fat?suppression sequence (PDWI?FS). Axial, coronal and sagittal scans, three?dimensional?double echo steady?state sequence (3D?DESS) and three?dimensional variable flip angle fast spin echo sequence (3D?SPACE) scans were also acquired. The results of the examination were independently analyzed by two radiologists (5 and 17 years of work experience, respectively) on the ligament, tendon, bone marrow and ankle joint injuries. When they had inconsistent views, the diagnosis provided by the third radiologist (27 years of work experience) was considered a final diagnosis. The relationship between ankle injury and different running postures, the number of participating in marathons and training intensity was analyzed, and the independent sample χ2 was used for statistical analysis. The consistency of two radiologists was tested by Kappa test. Results According to the inclusion and exclusion criteria, 39 subjects were included, with 64 ankles totally, 35 right ankles and 29 left ankles. MRI showed that (1) Ligament injuries: 28 ankles were anterior talofibular ligament injuriy;50 ankles were posterior talofibular ligament injury; 60 ankles the calcaneofibular ligament injuries and 54 ankles were deltoid ligament injuries, without complete injury. (2) Tendon sheath effusion and injuries: peritendinous effusion was common, with 47 flexor hallucis longus tenosynovitis, 49 posterior tibialis tenosynovitis, 37 flexor digitorum longus tenosynovitis, 7 peroneus longus tenosynovitis and 5 peroneus brevis tenosynovitis. (3) Synovitis effusion: 43 posterior ankle synovitis and local effusion. (4) Others: cartilage injury in 2 ankles, bone marrow edema in 8 ankles, and among them stress fracture in 2 ankles. The two radiologists had good consistency with the Kappa value of 0.91. Regarding the running posture, the incidence of ligaments injuries was obviously higher in those who landed on the hind foot than in those landed on front and middle foot,and the difference was statistically significant(P=0.013, χ2 value was 6.191).The incidence of tendon injuries was higher in those who landed on the front middle foot than in those landed on the hind foot, and the difference was statistically significant (P=0.029, χ2 value was 4.775). Those with larger training (training running ≥300 km/month) had significant ankle injury (P=0.005, χ2 value was 7.844). Conclusion The MRI features of ankle joint injuries in amateur marathon volunteers are related to different running postures and training intensity.

Quantitative T2*MRI study of knee articular cartilage of amateur marathon runners after running a half marathon / 中华放射学杂志

Objective To study the effects of half marathon loading on the T2* mapping assessment of knee joint cartilage. Methods Twenty male amateur marathon runners with more than three years of running age were enrolled. The T1WI, PDWI, 3D?DESS, and T2*mapping were performed on right knee joint before and after the half marathon within 3h and after a period of approximately 1 week. Cartilage was divided into 6 regions: medial and lateral femoral cartilage, medial and lateral tibial cartilage and patella and trochlea cartilage. Femoral cartilage was partitioned into central weight?bearing regions, posterior cartilage nonweight?bearing regions with the posterior boundary of the meniscus as the dividing mark. All cartilage was further divided into deep and superficial layers according to the thickness 1/2, and the ROI was delineated to obtain the T2* value of the corresponding area. One?way repeated measures analysis was performed to test the difference of T2*values pre?and post?marathon. LSD tests were used to estimate the different influences of physiological activities on each articular cartilage area. Results All cartilage areas of the knee joint did not show cartilage injury during the examination. The differences in the global T2*values of the superficial layers of the knee cartilage before and after the half?marathon marathon were statistically significant (t=5.145, P<0.05), but the global T2*value of the deep region were not (t=1.864, P>0.05). After a week, the T2* values of all cartilage areas were not statistically different from those before running (t=1.062, 0.309; P>0.05). Conclusion After a single half marathon, the changes of knee cartilage composition in male amateur marathon runners are reversible. In the absence of positive findings in conventional MRI, T2* mapping can indirectly reflect changes in biochemical composition of the articular cartilage during exercise.