Anticoncepção oral e hipotrofia muscular: existe correlação? / Oral contraception and muscle atrophy: is there a correlation?

As pílulas anticoncepcionais consistem na formulação combinada de um estrogênio e um progestagênio ou em apresentações simples de progestagênio isolado com a finalidade de bloquear a ovulação e alterar as condições do útero e das tubas uterinas, bloqueando parcialmente a foliculogênese e a inibição do pico de gonadotrofinas. Desse modo, no que concerne à temática, diversas publicações na mídia de ampla divulgação afirmam que os anticoncepcionais orais têm papel importante na sarcopenia e na hipotrofia, incluindo perda de força muscular e redução do desempenho físico. Assim, o presente trabalho tem por objetivo avaliar, por meio de pesquisas de artigos, a correlação entre anticoncepcionais hormonais orais e hipotrofia muscular. Foi concluído que os artigos científicos especializados no tema são ainda bastante inconclusivos, sugerindo que há indicações de que usuárias de anticoncepcional oral sejam mais suscetíveis ao dano muscular induzido por exercícios, contudo ainda não há consenso.

Anticonception pills consist of a combined formulation of an estrogen and a progestogen or simple presentations of progestogen alone with the purpose of blocking ovulation and altering the conditions of the uterus and uterine tubes, partially blocking folliculogenesis and inhibiting the gonadotropin peak. Thus, with regard to the subject, several widely publicized media publications claim that oral contraceptives play an important role in sarcopenia and hypotrophy, including loss of muscle strength and reduced physical performance. So, the present work aims to evaluate through article searches the correlation between oral hormonal contraceptives and muscle hypotrophy. It was concluded that scientific articles specialized on the subject are still quite inconclusive, suggesting that there are indications that oral contraceptive users are more susceptible to exercise-induced muscle damage, however there is still no consensus.

Exercise-induced muscle damage and physiotherapy: a visualized analysis / 中国康复理论与实践

ObjectiveTo conduct a visualized analysis of the researches related to the physiotherapy for exercise-induced muscle damage, identify the present situation, and predict the hotspots and developing trends. MethodsRelevant literature about physiotherapy of exercise-induced muscle damage were collected in Web of Science Core Collection from the establishment of the database to October 31, 2022, and CiteSpace 6.1.R3 software was used for visualized analysis. ResultsA total of 357 articles were included, involving 51 countries/regions, 532 authors and 346 institutions. The annual number of documents issued showed an overall upward trend. The country with the highest number of documents was the United States, the organization was Edith Cowan University, and the author was Howatson Glyn. Keywords with high attention in the last three years were performance, eccentric exercise, recovery and soreness. Cited document clustering words were exercise-induced muscle damage, delayed-onset muscle soreness, foam rolling and exercise performance. ConclusionExercise-induced muscle damage is a muscle micro-injury, and the most important concerns are post-injury muscle soreness, myofascial pain and ultrastructural changes. Researches about physiotherapy of exercise-induced muscle damage are gradually increasing. Main physiotherapy treatments include cryotherapy, cold water therapy, massage, foam rolling and eccentric exercise. Presently, eccentric exercise is a hot topic in this field, and foam rolling would be hot in the future.

A Review on the Effect of Nutrition on Exercise-Induced Muscle Damage (EIMD)

A muscle strain develops when a muscle lengthens or is torn. This would be frequently caused by muscle exhaustion, abuse, or misuse. Exercise-Induced Muscle Damage (EIMD) is defined based on indicators appearing soon after initiating an exercise session and continues for up to 14 days after the end of the session. Muscle damage from trauma, inherited genetic illnesses, pathology or complete circumstances are highly common and cause significant socio-economic consequences. Athletes care about EIMD-related loss of muscle strength and discomfort since they can affect their performance significantly. This current review is intended to highlight the updated findings and its present preventive and management strategies. The review also discussed the pathophysiology behind EIMD in detail to highlight the understanding points regarding EIMD. The frequency of EIMD following exercise must are linked with strength training, and muscle strain as measured by an increased level of serum kinase (CK). the percentage of tissue micro-injuries. EIMD is quite frequent among athletes and also among the general population. This review has discussed the available diet and nutrition to prevent such EIMD and tackle, it if EIMD sets in. Finally, this current review has covered EIMD from all the phases and recommendations have been made for further study, especially in clinical trials.

O efeito agudo do fst-7 no desempenho, variáveis metabólicas e respostas perceptivas em homens bem treinados / Acute effect of fst-7 on performance, metabolic variables, and perceptual responses in well-trained men

O método Fascia Stretch Training 7 Sets (FST-7) ganhou popularidade nos últimos anos sendo disseminado por fisiculturistas norte-americanos. O objetivo do presente estudo foi comparar os efeitos do protocolo de treinamento do método FST-7 com ou sem alongamento passivo entre as séries nas variáveis metabólicas (lactato [LAC] e creatinofosfoquinase [CPK]), desempenho (volume total de treinamento ­ VTT) e percepção subjetiva de esforço (PSE) em homens bem treinados. Nove homens (23, 2 ± 1,7 anos; 174,2 ± 6,2 cm; 84,6 ± 9,8 kg, 3,4 ± 1,0 anos de experiência em treinamento de força) foram submetidos ao teste e re-teste de 10 repetições máximas (10RM) nos exercícios supino reto livre e crucifixo horizontal com halteres em dias distintos, respeitando 48 horas de intervalo entre a s sessões de teste e re-teste. Decorridas 72 horas do último dia de teste, os participantes realizaram os protocolos experimentais de forma randomizada com 72 horas de intervalo entre as sessões. As coletas sanguíneas foram realizadas 10 minutos antes e imediatamente após os protocolos de treinamento. O protocolo sem alongamento aumentou significativamente a concentração de LAC (p = 0,029). No entanto, o mesmo não ocorreu para a concentração de CPK (p = 0,302). O VTT foi maior para o protocolo sem alongamento (p < 0,001) e a PSE foi maior para o protocolo com alongamento entre as séries (p = 0,003). Concluímos que o método FST-7 com alongamento resultou em uma maior PSE, o que pode estar relacionado com o declínio do desempenho, traduzido pelo menor VTT em relação à condição sem alongamento. Adicionalmente, o menor VTT pode ter afetado o menor acúmulo de LAC observado no método FST-7 com o alongamento. (AU)

The Fascia Stretch Training 7 Sets (FST-7) method has gained popularity in the recent years being disseminated by American bodybuilders. The purpose of the study was to compare the effects of the Fascia Stretch Training 7 Sets (FST-7) method with or without passive stretching between sets on metabolic variables (lactate [LAC] and creatine kinase [CK]), performance (total training volume - TTV) and rating of perceived exertion (RPE) in trained men. For this, nine recreationally trained men (23.2 ± 1.7 years; 174.2 ± 6.2 cm; 84.6 ± 9.8 kg, 3.4 ± 1.0 years of experience in strength training) were submitted to the test and re-test of 10 repetition maximum (10RM) in the barbell bench press and fly with dumbbells on different days, respecting a 48-hour interval between the test and re-test sessions. After 72 hours of the last test day, participants performed the experimental protocols in randomized order with a 72-hour interval between sessions. Blood samples were taken 10 minutes before and immediately after the training protocols. The protocol without stretching was significantly increased LAC concentrations (p = 0.029). However, the same did not occur for the concentration of CK (p = 0.302). The TTV was higher for the protocol without stretching (p < 0.001), and the RPE was significantly higher for the protocol with stretching between sets (p = 0.003). We concluded that the FST-7 method with stretching resulted in higher RPE, which may be related to the decline in performance, translated by the lower TTV in relation to the condition without stretching. This lower TTV may have affected the lower LAC accumulation observed in the FST-7 method with stretching. (AU)

The effects of active vs. passive recovery on riding performance during a simulated motocross race

Abstract Aims: Motocross consists of two races of 30 min with a break in between. Recovery between races is paramount to performance, this study aimed to compare the effects of active and passive recovery between motocross races on riding performance. Methods: Thirteen elite and non-elite racers performed two races of 30 min with 1 h break, twice with two-week interval. Between the races active (20 min ergometer cycling at 60% of HRmax) or passive recovery (no activity) were executed in a randomized order. Lap times, heart rate during riding, blood lactate, reaction time, handgrip strength, upper back pull strength, counter movement jump height, and medicine ball throw distance were measured before and after both races. Serum creatine kinase enzyme activity and strength tests were assessed also 24 h after the races. Results: No statistically significant differences were observed in any variables between protocols. A significant drop in handgrip strength was found post-race values (p < 0.001). Post-racing creatine kinase values were above resting levels. Conclusion: These results do not support the use of active recovery in between motocross races for restoration of neuromuscular or riding performance. Motocross seems to cause some exercise-induced muscle damage; thus, some rest is required to recover homeostasis.

Effects of cumulative school soccer matches separated by 24-h or 48-h intervals on physical recovery status of U-19 players / Efeitos de partidas consecutivas de futebol escolar com intervalos de 24 e 48 horas no estado de recuperação física de jogadores Sub-19

Abstract This study aimed to evaluate the effects of cumulative school soccer matches separated by 24-h or 48-h intervals on the recovery status of U-19 players. Thirty-four school athletes (17.6 ± 1.1 years) who played in an U-19 school soccer competition (composed of one group with four teams and another group with three teams, followed by semifinals and final) were examined before three matches, which lasted 70 min. Seventeen athletes had a 24-h rest interval between each match (GGG group), while 18 athletes had a 48-h rest interval between the second and third matches (GG48hG group). Total Quality Recovery, countermovement jump, 10-m sprint, and maximum lumbar isometric strength were measured. The internal load of each match was calculated by the product of the session Rating of Perceived Exertion and match time. There was a 22% reduction in Total Quality Recovery (p< 0.001) and 12% in 10-m sprint performance (p< 0.001) before the third match in the GGG group, while the GG48hG group showed no changes for the same variables (p> 0.05). The countermovement jump decreased before the second match in both groups (GGG= 12% and GG48hG= 10%; p< 0.001), with no difference between groups (p> 0.05). In addition, both groups showed no changes in the isometric strength or the internal load match over the games (p> 0.05). Despite not providing complete muscle recovery, a 48-h interval between the second and third matches seems to have minimized the reduction of muscle performance due to consecutive matches.

Resumo Este estudo teve como objetivo avaliar os efeitos de partidas consecutivas de futebol escolar com intervalos de 24 e 48 horas no estado de recuperação física de jogadores Sub-19. Foram avaliados 35 homens (17,6±1,1 anos) atletas escolares sub-19. Durante a competição, foram realizados três jogos de 70-min de duração. Dezessete atletas tiveram intervalo de 24h entre cada jogo (grupo GGG). Dezoito atletas tiveram intervalo de 48 h entre o 2º e o 3º jogo (grupo GG48hG). Antes de cada jogo foram medidas a Qualidade Total de Recuperação, altura do salto com contra movimento, velocidade no sprint de 10-m, e força máxima isométrica lombar máxima. A carga interna do jogo foi calculada pelo produto da percepção subjetiva do esforço da sessão e tempo de cada jogo. Houve uma redução de 22% na qualidade total de recuperação (p <0,001) e de 12% no desempenho de sprint de 10 m (p <0,001) antes da terceira partida no grupo GGG, enquanto o grupo GG48hG não apresentou alterações para as mesmas variáveis (p> 0,05). O salto com contra movimento diminuiu antes da segunda partida em ambos os grupos (GGG = 12% e GG48hG = 10%; p <0,001), sem diferença entre os grupos (p> 0,05). Em adição, ambos os grupos não apresentaram alterações na força isométrica e na carga interna ao longo dos jogos (p> 0,05). Apesar de não proporcionar uma completa recuperação muscular, 48 h de intervalo entre o segundo e o terceiro jogo parece ter minimizado o efeito de jogos consecutivos na redução do desempenho.

Effect of aquatic exercise after eccentric contraction-induced muscle injury / Efeito do exercício aquático depois de lesão muscular provocada por contração excêntrica / Efecto del ejercicio acuático después de una lesión muscular por contracción excéntrica

ABSTRACT Introduction: Muscle microlesions produced by eccentric contractions (EC) cause changes in strength, endurance, power and neuromuscular activity parameters for an extended period of time. Objectives: To investigate the effect of aquatic exercise after EC-induced muscle injury on strength, endurance, power and neuromuscular activity parameters. Methods: A cross-sectional experimental study with six subjects (age 25 ± 4 years, weight 77 ± 4kg and height of 162 ± 2 cm) with EC-induced muscle injury followed up during a recovery period (48h, 72h and 96h) without intervention (Group 1A) and involving aquatic exercises (Group 1B). Dynamic and isometric strength, muscular endurance, and vertical/horizontal power tests as well as vastus lateralis neuromuscular activity measurements were performed before, immediately after, and during the recovery period. Results: Our results indicate that the intervention in Group 1B, when compared to Group 1A, accelerated the recovery of dynamic (p <0.01) and isometric (p <0.03) strength at 48h and 72h, increased vertical power at 48h (p <0.05) and horizontal power at 48h and 72h (p <0.05), and reduced neuromuscular activity (p <0.05) at 48h and 72h after EC. Conclusions: According to our findings, performing aquatic exercises during the recovery period improves muscle efficiency and accelerates strength, power and neuromuscular activity recovery. Level of evidence l; Randomized clinical trial.

RESUMO Introdução: As microlesões musculares geradas por contrações excêntricas (CE) provocam alterações dos parâmetros de força, resistência, potência e atividade neuromuscular por período prolongado. Objetivos: Investigar o efeito do exercício aquático depois de lesão muscular provocada por CE sobre os parâmetros força, resistência, potência e atividade neuromuscular. Métodos: Estudo experimental cruzado com seis indivíduos (idade 25 ± 4 anos, peso 77 ± 4 kg e altura 162 ± 2 cm) com lesão muscular por CE e acompanhados durante um período de recuperação (48 h, 72 h e 96 h) sem intervenção (Grupo 1A) e envolvendo exercícios aquáticos (Grupo 1B). Antes, imediatamente e durante o período de recuperação foram realizados testes de força dinâmica, isométrica, resistência muscular, potência vertical/horizontal e mensuração da atividade neuromuscular do músculo vasto lateral. Resultados: Nossos resultados apontam que a intervenção no Grupo 1B, em comparação com o Grupo 1A, acelerou a recuperação da força dinâmica (p < 0,01) e isométrica (p < 0,03) nos tempos de 48 h e 72 h, aumentou a potência vertical no tempo de 48 h (p < 0,05) e a horizontal nos tempos de 48 h e 72 h (p < 0,05) e reduziu a atividade neuromuscular (p < 0,05) nos tempos de 48 h e 72 h depois de CE. Conclusões: De acordo com nossos achados, apontamos que os exercícios aquáticos durante o período de recuperação melhoram a eficiência muscular e aceleram a recuperação de força, potência e atividade neuromuscular. Nível de evidência l; Estudo clínico randomizado

RESUMEN Introducción: Las microlesiones musculares generadas por contracciones excéntricas (CE) provocan alteraciones de los parámetros de fuerza, resistencia, potencia y actividad neuromuscular por período prolongado. Objetivos: Investigar el efecto del ejercicio acuático después de una lesión muscular provocada por CE sobre los parámetros fuerza, resistencia, potencia y actividad neuromuscular. Métodos: Estudio experimental cruzado con seis individuos (edad 25±4 años, peso 77±4kg y altura 162±2cm) con lesión muscular por CE y acompañados durante un período de recuperación (48h, 72h y 96h) sin intervención (Grupo 1A) e involucrando ejercicios acuáticos (Grupo 1B). Antes, inmediatamente después y durante el período de recuperación, fueron realizados tests de fuerza dinámica, isométrica, resistencia muscular, potencia vertical/horizontal y medición de la actividad neuromuscular del músculo vasto lateral. Resultados: Nuestros resultados apuntan que la intervención en el Grupo 1B, en comparación con el Grupo 1A, aceleró la recuperación de la fuerza dinámica (p<0,01) e isométrica (p<0,03) en 48h y 72h, aumentó la potencia vertical en el tiempo de 48h (p<0,05) y la horizontal en los tiempos de 48h y 72h (p<0,05) y redujo la actividad neuromuscular (p<0,05) en los tiempos de 48h y 72h después de la CE. Conclusiones: De acuerdo con nuestros hallazgos, apuntamos que los ejercicios acuáticos durante el período de recuperación mejoran la eficiencia muscular y aceleran la recuperación de fuerza, potencia y actividad neuromuscular. Nivel de evidencia l; Estudio ensayo clínico aleatorizado.

Long distance training associated to HIIT protocol does not induce changes in blood biochemical markers in adult marathoners

ABSTRACT Objective: to verify blood markers during a 12-week training protocol and after Sao Paulo Marathon. Methods: Blood samples of 9 male marathoners were collected before (C1) and after (C2) 12-week training protocol, before (C3) and after (C4) marathon. Muscle and liver damage markers (creatine kinase [CK-MM], aspartate aminotransferase [AST], alanine aminotransferase [ALT]), oxidative stress levels (thiobarbituric acid reactive substances [TBARS]) and serum iron concentration were measured. Results: changes were identified comparing moment C4 to other moments for CK-MM and iron. For AST, ALT, and TBARS no differences were identified. Conclusion: strenuous exercises might elicit changes on blood markers, needing follow up strategies to avoid impairments to athletes' performance and health.

RESUMO Objetivo: verificar marcadores sanguíneos durante 12 semanas de treinamento e após a Maratona de São Paulo. Metodologia: amostras de sangue de 9 maratonistas foram coletadas antes (C1) e após (C2) o treinamento de 12 semanas, antes (C3) e após (C4) a maratona. Marcadores sanguíneos e hepáticos (creatina quinase [CK-MM], aspartato aminotransf. [AST], alanina aminotransf. [ALT]), níveis de estresse oxidativo (subst. reativas ácido tiobarbitúrico [TBARS]) e ferro sérico foram analisados. Resultados: Verificaram-se alterações de CK-MM e ferro entre C4 e os outros momentos. Para AST, ALT e TBARS não se encontrou diferenças. Conclusão: exercícios exaustivos podem causar alterações em marcadores sanguíneos, requerendo estratégias de monitoramento para evitar danos ao desempenho e saúde do atleta.

RESUMEN Objetivo: evaluar marcadores sanguíneos durante 12 semanas de entrenamiento y después del Maratón de São Paulo. Metodología: muestras de sangre de 9 maratonistas fueron recogidas antes (C1) y después (C2) el entrenamiento, y antes (C3) y después (C4) a maratón. Se analizaron marcadores sanguíneos y hepáticos (creatina quinasa [CK-MM], aspartato aminotransf. [AST], alanina aminotransf. [ALT]), estrés oxidativo (sustancias reactivas del ácido tiobarbitúrico [TBARS]) y de hierro. Resultados: Se encontraron cambios comparando C4 y otros momentos para CK-MM y hierro. Para AST, ALT y TBARS no se encontraron diferencias. Conclusión: ejercicios extenuantes pueden causar cambios en marcadores sanguíneos, requiriendo estrategias de monitoreo para evitar daños al desempeño y salud del atleta.

Neuromuscular and physiological responses to different training loads in Randori of elite judo athletes

Abstract Aim: To compare two different randori structure (high volume and short pauses - TRAD training vs low volume with long pauses - COMP training) in the neuromuscular and metabolic responses of elite judo athletes. Methods: The first situation (TRAD) consisted of 12 randoris of 5 minutes with 45 seconds rest, and the other situation (COMP), consisted of 6 randoris of 5 minutes with 10 minutes between them. Physiological (Blood Lactate and Creatine Kinase), neuromuscular (Countermovement Jump and Medicine Ball Throws) and perceptive variables (Rating Perceived Exertion) were measured before and at the end of the sessions. Results: The subjective perception of effort at the end of the training was significantly higher in the TRAD training type (TRADpost: 8.1 ± 0.9 AU; COMPpost: 6.6 ± 1.5 AU, p <0.001). Blood lactate concentration (TRADpost: 6.4 ± 2.2 mmol/L; COMPpost: 8.1 ± 2.9 mmol/L; p <0.001), CMJ height (TRADpost: 36.2 ± 4.6 cm; COMPpost: 35.9 ± 4.3 cm, p = 0.012) and upper limb power performance (TRADpost: 6.4 ± 0.9 m; COMPpost: 6.3 ± 0.9 m p = 0.03) were significantly higher at the end of the two training sessions compared to their start, but there are no group effect. There is group effect in CK (TRADpost: 490.7 ± 273.5 U/L; COMPpost: 357.4 ± 203.8 U/L; p <0.001). Conclusions: This study demonstrated that TRAD and COMP Judo training induced similar physical demands, and both seem to not be enough to reach higher intensities, which made them distant methods of competitive reality.

Effect of exercise-induced muscle damage on desmin aggregates / 中国组织工程研究

BACKGROUND: Protein degradation is the main reason of exercise induced muscle damage (EIMD). High-intensity exercise may lead to the misfolding of proteins and form aggregates, which is harmful to the ultrastructure of skeleton muscle. OBJECTIVE: To determine the formation and role of protein aggregate (especially the desmin aggregate) in EIMD. METHODS: Sixty-four adult male Sprague-Dawley rats (purchased from Beijing Vital River Laboratory Animal Technology Co., Ltd., China) were randomly divided into eight groups (control, post-exercise 0, 3, 6, 12, 24, 48, and 72 hours, eight rats in each). A damage model was established by downhill running (-16°, 16 m/min, 90 minutes). All rats were then killed at corresponding time points to take the soleus as specimen. Severity of damage was observed histologically under a transmission electron microscope. Expression of ubiquitin in the insoluble protein of soleus muscle was detected using western blot, and expression of desmin aggregates was observed by immunofluorescence double labeling. All experimental procedures were approved by the Beijing Sport University Institutional Review Board. RESULTS AND CONCLUSION: (1) After a large-load eccentric exercise, the sarcomere of the soleus muscle was widened, the Z-line was broken, and the myofibril was broken and distorted, all of which was most serious at 12 hours after exercise, and recovered completely at 72 hours after exercise. (2) Western blot results indicated that the expression of ubiquitin in the skeletal muscle increased first and then decreased after a large-load eccentric exercise. The expression peaked at 12 hours after exercise and returned to normal at 72 hours after exercise. (3)Overall expression of desmin aggregates significantly raised (P < 0.01) instantly when the EIMD occurred. It reached the peak at 12 hours after exercise, then reduced somewhat (P < 0.01) at 24 and 48 hours, and finally recovered at 72 hours. (4)These findings indicate that desmin aggregation may be one of the causes of EIMD.

La inmersión en agua fría no reduce los marcadores de daño muscular en nadadores / Immersion in cold water does not reduce markers of muscle damage in swimmers / Efeito da imersão em água fria sobre os marcadores de dano muscular (CK; LDH) devidos ao exercício excêntrico em nadadores de Medellin

Objetivo: determinar el efecto de la inmersión en agua fría sobre los marcadores de daño muscular inducidos por el ejercicio excéntrico. Metodología: estudio cuasi-experimental, con 15 hombres nadadores, 10 en el grupo de tratamiento y 5 en el grupo control. Luego del protocolo excéntrico, con 2 series de 10 repeticiones en extensión de rodilla, el grupo de tratamiento tuvo 15 minutos de inmersión en agua fría, a 15 °C ± 1 °C, y el grupo control tuvo 15 minutos de inmersión en agua termoneutra, a 32 °C ± 1 °C. Las variables (CK, LDH, salto vertical, potencia y percepción del dolor) se registraron a las 24, 48 y 72 horas posteriores a la intervención. Resultados: la inmersión en agua fría no tiene efectos estadísticamente significativos en la reducción de los marcadores de daño muscular.

Objective: To determine the effect of immersion in cold water on markers of muscle damage induced by eccentric exercise. Methodology: Quasi-experimental study, with 15 male swimmers, 10 in the treatment group and 5 in the control group. After the eccentric protocol, with 2 series of 10 repetitions in knee extension, the treatment group had 15 minutes of immersion in cold water, at 15 °C ± 1 °C, and the control group had 15 minutes of immersion in thermoneutral water, at 32 °C ± 1 °C. The variables (CK, LDH, vertical jump, power and pain perception) were recorded at 24, 48 and 72 hours after the intervention. Results: Immersion in cold water has no statistically significant effects in reducing markers of muscle damage.

Objetivo: Determinar o efeito da imersão em água fria sobre os marcadores de dano muscular induzido por exercício excêntrico. Metodologia: Estudo quase experimental, 15 homens nadadores, 10 no grupo de tratamento e 5 no grupo de controle. Após o protocolo excêntrico (2 séries de 10 repetições na extensão do joelho), o grupo de tratamento teve 15 minutos de imersão em água fria a 15 ° C ± 1 ° C e o grupo controle teve 15 minutos de imersão em água termo-neutra a 32 ° C ± 1 ° C. As variáveis (CK, LDH, salto vertical, potência e percepção da dor) foram registradas nas 24, 48 e 72 horas após a intervenção. Resultados: A imersão em água fria não tem efeitos estatisticamente significativos na redução dos marcadores de dano muscular.

Football training session rises creatine kinase but does not impair performance

Aim: Determine the relationship between changes in oxidative stress markers, muscle damage, DOMS, and their relationship with performance in response to a session of football training during a 1-week recovery period of young football players. Methods: Nineteen young football players aged 16.7±1.0 years were included in the study. After initial evaluation for basal levels of oxidative stress and muscle damage markers, DOMS, and performance testing (Vertical Jump, Agility T-test, and RAST potency test), the athletes were submitted to a routine training session composed of squatting exercises, followed by a simulated football match of 45 minutes. Athletes were reevaluated for 3 consecutive days (24h, 48h, and 72h after the training session) during the recovery week. Results: An elevated DOMS score in the quadriceps and posterior thigh (P<0.05) and serum CK was observed 24h to 72h after the training session. Despite elevated DOMS and CK muscle damage markers, no changes were observed in the vertical jump test, RAST potency test, or agility T-test during the recovery week. In addition, no changes in the oxidative stress markers analyzed MDA, AOPP, and GSH were observed during the recovery week. Conclusion: Training sessions with squatting exercises and simulated matches promote a rise in CK and DOMS, but not sufficient to impair physical performance during the training week in young players.(AU)

Atrofia paraespinal postoperatoria. ¿El abordaje importa? / Postoperative paraspinal atrophy. Does boarding matter?

Objetivo: Comparar la magnitud de la atrofia muscular postoperatoria que producen tres abordajes en fusiones lumbares segmentarias para patología degenerativa (línea media vs. Wiltse vs. MIS TLIF). Material y métodos: Se realizó un estudio observacional, transversal, multicéntrico, descriptivo y retrospectivo, de una serie de pacientes operados por patología degenerativa lumbar. Analizamos 45 pacientes (24 mujeres), con una edad media de 58.7 años, operados en 5 centros quirúrgicos entre 2015 y 2018. Se realizó una fusión instrumentada de un nivel, desde L3 hasta S1 (7 casos L3-L4, 25 casos L4-L5 y 13 casos L5-S1). Quince casos fueron realizados por abordajes por línea media, 15 por abordaje de Wiltse y 15 MIS TLIF. Todos fueron estudiados con Resonancia Magnética preoperatoria y con un mínimo de 6 meses luego de la cirugía (media de 14.6 meses). Estas fueron analizadas por 3 observadores especialistas en cirugía de columna. Se tomaron 2 variables para comparar el grado de atrofia entre pre y postoperatorio: área de sección transversal (AST) de músculo multifidus (MM) y erectores espinales (EE) y grado de infiltración grasa (IG) mediante la clasificación visual de Kjaer. Los análisis realizados fueron ejecutados utilizando el programa estadístico RStudio (versión 1.1.383) y se compararon valores de p obtenidos mediante la suma de rangos de Wilcoxon. Resultados: No se encontraron diferencias significativas entre los distintos abordajes en relación a la atrofia del MM. La comparación de p para AST de los EE mostró diferencias entre MIS TLIF vs línea media (p 0.018) y de línea media vs Wiltse (p 0.027). Conclusión: Los abordajes mínimamente invasivos utilizados para descompresión y artrodesis monosegmentaria lumbar, tuvieron más impacto sobre la atrofia muscular en los EE que en MM. Estudios randomizados y controlados serían de utilidad para validar los resultados de este trabajo.

Aim: To compare the level of post-operative muscle atrophy associated with three different approaches to achieve segmental lumbar fusion in patients with degenerative back disease: (1) the standard midline approach; (2) Wiltse's minimally-invasive surgery (MIS-W) approach; and (3) minimal-invasive surgery (MIS) with transforaminal lumbar interbody fusion (MIS-TLIF). Methods and Materials: A multi-center, observational, cross-sectional, retrospective study was performed on a series of patients who had undergone surgery for degenerative lumbar disease. All patients were studied preoperatively and for at least six months post-operatively (mean follow-up: 14.6 months) by magnetic resonance imaging (MRI), all images analyzed by three spine-imaging specialists. Three variables were used to compare the level of atrophy before and after surgery: (1) the cross sectional area (CSA) of the multifidus muscle (MM); (2) the CSA of the spinal erector muscles (SEM); and (3) fat infiltration level, as rated per the Kjaer visual classification system. Inter-group differences in these three outcomes were assessed using Wilcoxon rank sum tests. Results: Forty-five patients (24 females), of mean age 58.7 years, underwent surgery at five participating surgical centers between 2015 and 2018. One-level instrumented fusion, from L3 to S1, was performed: at the L3-L4 level in seven patients, L4-L5 in 25, and L5-S1 in 13. Surgical access was split evenly between the three approaches, each performed in 15 patients. No significant differences were detected between the approaches, in terms of MM atrophy or fat infiltration level. Less CSA-SEM atrophy was detected with the MIS-TLIF than midline (p = 0.018), and with the MIS-W than midline (p = 0.027) approach. Conclusions: Relative to the standard midline approach, two minimally-invasive surgery approaches used for decompression and lumbar mono-segmental arthrodesis reduced atrophy in the spinal erector muscles, but not the multifidus muscle. Randomized controlled trials might be useful to validate the results of this investigation.

Efectos de un entrenamiento de miembro inferior con restricción parcial del flujo sanguíneo en la fuerza muscular y biomarcadores sistémicos de daño muscular e inflamación / Effects of lower limb training with partial restriction of blood flow on muscle strength and systemic biomarkers of muscle damage and inflammation

El entrenamiento de fuerza, especialmente con alta intensidad de carga, permite aumentar la fuerza y trofismo muscular, pero también se asocia a daño muscular inducido por ejercicio (DMIE). Una nueva modalidad de entrenamiento, combina una baja intensidad de carga con la restricción parcial del flujo sanguíneo (RPFS) alrededor del músculo, siendo prometedor en cuanto el desarrollo de la fuerza y trofismo muscular. El objetivo del estudio fue comparar el rendimiento de fuerza máxima de los músculos cuádriceps e isquiotibiales (FM-Q y FM-I) y marcadores de daño muscular (CK) e inflamación sistémica (PCRus) entre un entrenamiento de baja intensidad de carga con RPFS, versus uno de alta y otro de baja intensidad de carga sin RPFS en jóvenes físicamente activos durante cuatro semanas de entrenamiento. Veintitrés participantes midieron la FM-Q y FM-I previo y al término de la intervención; además, antes del inicio de la primera sesión, y antes y después del término de la última sesión se midió la CK y PCRus. En los tres tipos de entrenamiento se produjeron aumentos equivalentes en la fuerza máxima, a excepción de la FM-Q del entrenamiento con baja intensidad sin RPFS. Solo en el entrenamiento con RPFS la CK y PCRus se modifican al finalizar la intervención, y aun cuando el estrés miocelular parece ser más alto que en los otros tipos de entrenamiento, no indicaría daño muscular.

Strength training, especially with high load intensity, allows increasing muscle strength and trophism, but it is also associated with exercise-induced muscle damage (EIMD). A new training modality, a combination of loading with the partial restriction blood flow (PRBF) around the muscle, being promising in the development of strength and muscular trophism. The aim of the study was to compare the maximum strength (MS) performance of quadriceps and hamstrings (MS-Q and MS-I) and muscle damage biomarkers (Creatine Kinase, CK) and systemic inflammation (high sensitivity - CRP, hs-CRP) between a low intensity load training with PRBF, versus one high and another low load intensity without PRBF in physically active youngsters during four weeks of training. Twenty-three participants measured MSQ and MS-I and the intervention term. In addition, before the start of the first session, before and after the end of the last session, CK and hsCRP were measured. In the three types of training the equivalent benefits in MS are produced, an exception of the MS-Q of low intensity training without PRBF. Only in the training with PRBF, the CK and hsCPR are modified at the end of the intervention, and even though the myocellular stress seems to be higher than in the other types of training, it would not indicate muscle damage.

The influence of combat simulation exercises on indirect markers of muscle damage in soldiers of the brazilian army / A influência do exercício de simulação de combate sobre marcadores indiretos de lesão muscular em soldados do exército brasileiro

The combat simulation exercise is a military activity where combat activities characterized by intense physical activity are simulated. The aim of this study was to describe the behavior of indirect markers of muscle damage during military activities of combat simulation with the realization of strenuous physical efforts. This study was conducted with military recruits/volunteers (n=43; 19-24 age group) from the COMANDOS Army Corporal Training Course. The biomarkers were evaluated at the baseline (T0), 72 hours after the baseline (T1) and 63 hours after the end of the activity (T2). To compare the variables analyzed at different times, an analysis of variance (ANOVA) was applied to repeated measures with post hoc Tukey's test to identify the statistically significant differences. The criteria of significance adopted was the value of p<0,05. On average, the total body mass was significantly greater in T0 when compared to T1 (74,4kg x 69,8Kg; p< 0,05). In relation to the biochemical markers, on average, the serum levels were significantly higher (p<0,001) in T1 when compared to T0: CPK, LDH, CRP, Mb and AGPA. After 63 hours of rest, on average, the serum levels of the biochemical markers were significantly lower than in the moment T1: CPK, LDH, CRP, Mb and AGPA. However, after 63 hours of the end of the activity, all variables evaluated returned to baseline, with the exception of LDH, that on an average remained above the values observed in the moment T0. This study made possible to understand the behavior of indirect markers of muscle damage during the COMANDOS Army Corporal Training Course. However, others studies are necessary, regarding to Training Courses such as: paratrooper, mountain, jungle warfare and others to try establish a possible range of reference values for this markers during military activities.

O exercício de simulação de combate é uma atividade militar, onde as atividades de combate caracterizadas por intensa atividade física são simuladas. O objetivo deste estudo foi descrever o comportamento dos marcadores indiretos de lesão muscular durante as atividades militares de simulação de combate com a realização de esforços físicos extenuantes. Este estudo foi realizado com militares voluntários (n = 43; faixa etária = 19-24 anos) do Curso de Formação de Cabos do Exército. Os biomarcadores foram avaliados na linha de base (T0), 72 horas após o início das atividades (T1) e 63 horas após o final da atividade de (T2). Uma análise de variância (ANOVA) para medidas repetidas, com teste post hoc Tukey, foi aplicada para identificar as diferenças estatisticamente significativas nas variáveis analisadas em momentos diferentes. O critério de significância adotado foi o valor de p <0,05. Em média, a massa corporal total foi significativamente maior no T0 quando comparado a T1 (74,4kg x 69,8Kg; p <0,05). Em relação aos marcadores bioquímicos, em média, os níveis séricos foram significativamente maiores (p <0,001) em T1 quando comparados com T0 para: CPK, LDH, CRP, Mb e AGPA. Após 63 horas de descanso, em média, os níveis séricos dos marcadores bioquímicos (CPK, LDH, CRP, Mb e AGPA ) foram significativamente menores do que no momento T1. No entanto, após 63 horas a partir do fim da atividade, todas as variáveis avaliadas retornaram à linha de base, com a exceção do LDH, que, em média, manteve-se significativamente maior do que os valores observados no momento T0. Este estudo possibilitou compreender o comportamento dos marcadores indiretos de lesão muscular durante o Curso de Formação de Cabos COMANDOS. No entanto, outros estudos são necessários, com relação a cursos de formação, tais como: paraquedistas, montanha, guerra na selva, e outros, para tentar estabelecer uma possível faixa de valores de referência para estes marcadores durante as atividades militares.

Clinical Correlation between Muscle Damage and Oswestry Disability Index Score after Open Lumbar Surgery: Does Open Surgery Reduces Functional Ability?

STUDY DESIGN: Single-surgeon, single-center prospective study with prospective data collection. PURPOSE: To clinically evaluate muscle damage after open lumbar surgery and its relationship to functional activity and to validatethe improvement in function as indicated by improved Oswestry Disability Index (ODI) score despite muscle damage. OVERVIEW OF LITERATURE: Few studies have analyzed the functional loss and recovery pattern of muscles after open lumbar surgery. METHODS: The study included 30 patients who underwent open lumbar spine fusion surgery at our institution between August 2013 and May 2015. Preoperatively and at 6 months postoperatively, the patients were subjected to functional, biochemical, electrophysiological, and radiological assessments as outpatients, and the results were compared. RESULTS: Mean preoperative and 6-month postoperative values were as follows: creatine phosphokinase levels, 133.07±17.57 and 139±17.7 U/L (p<0.001); Visual Analog Scale scores for backache, 6.73±0.88 and 3.27±0.96 (p<0.001); and ODI scores, 41.6±5.51 and 22.4±4.48 (p<0.001), respectively. Preoperatively, electrophysiological studies showed that 20% of the patients had a polyphasic configuration whereas at 6 months postoperatively, all patients had polyphasic configuration (p<0.001). The mean cross-sectional area of the multifidus observed using magnetic resonance imaging (MRI) decreased from 742.67±76.62 mm2 preoperatively to 598.27±66.38 mm2 6 months postoperatively (p<0.001), with all the patients exhibiting grade 2 atrophy. CONCLUSIONS: Open lumbar fusion surgery resulted in significant damage to the lumbar paraspinal muscles, as indicated by a reduction in the cross-sectional area of the multifidus by MRI and denervation of the multifidus demonstrated using electromyography. Nevertheless, the patients reported reduced back pain and improved quality of life, which may have been due to increased stability of the previously unstable lumbar spinal segment after the surgery.

Acute effects of Resistance exercise performed on ladder on energy metabolism, stress, and muscle damage in rats

Abstract AIMS To evaluate the acute effects of a resistance exercise session performed on ladder on energy metabolism, stress, and muscle damage in rats. METHODS Male Wistar rats were randomly distributed in Exercise (E) (n=30) and Control (C) (n = 20) groups. The E group performed a resistance exercise session on a vertical ladder with weights on their tails. Blood samples were collected at rest and after each climb to analyze lactate levels and ten minutes after the last climb to analyze lactate dehydrogenase (LDH), creatine kinase (CK), and corticosterone levels. RESULTS Blood lactate levels remained stable during exercise. Serum corticosterone, blood glucose, LDH and CK levels increased and glycogen content decreased in the E group, when compared to the C group. CONCLUSION These results suggest that resistance exercise performed on ladder is a model of high-intensity exercise. However, the stabilization of lactate during the session suggests that the aerobic metabolism is an important factor during the intervals between climbs.(AU)

Effects of MG53 knock-out on skeletal muscle damage of mice during delayed onset muscle damage / 中国康复医学杂志

Objective:To discuss the effect of knock-out MG53 on skeletal muscle,and to determine whether MG53 can protect skeletal muscle from injury during delayed onset muscle damage(DOMS).Method:Eighty-four eight-week old C57 mice were divided into two groups due to their gene (WT and KO),and each group were divided into 7 subgroups again.14 groups,6 mice in each.They were WC,WE0,WE2,WE12,WE24,WE48,WE72 and KC,KE0,KE2,KE12,KE24,KE48,KE72.At each time point after 3 days eccentric exercise,the mice were decapitated after drawing blood.The rectus femoris of left leg was used to detect the level of MG53 with Western blot,the other side were used to do electron microscope analysis.Blood CK were measured also.Result:The CK of K0 raised remarkably and decreased gradually until W 12.But the second peak appear at W24 and decreased again gradually since then.Ultrastructural changes of skeletal muscle after eccentric exercise at different time points is obvious.The injury is worsen gradually from Wo to W24,and improved gradually from W48 to W72.Comparing with W groups,the injury in K group were even worsen an each time point.The MG53 of W0 and W24 were 16％ and 11％ higher than those before exercise (p＜0.05)and restored to normal in 72 hours after exercise.Conclusion:The injury after severe exercise is more severity in MG53 knock-out mouse than those in wild mouse.and the MG53 protein increased significantly.It suggests that MG53 may significantly relieve the skeleton muscle injury in delayed muscle sore period.

Ursolic acid supplementation decreases markers of skeletal muscle damage during resistance training in resistance-trained men: a pilot study

Ursolic acid (UA) supplementation was previously shown to improve skeletal muscle function in resistance-trained men. This study aimed to determine, using the same experimental paradigm, whether UA also has beneficial effects on exercise-induced skeletal muscle damage markers including the levels of cortisol, B-type natriuretic peptide (BNP), myoglobin, creatine kinase (CK), creatine kinase-myocardial band (CK-MB), and lactate dehydrogenase (LDH) in resistance-trained men. Sixteen healthy participants were randomly assigned to resistance training (RT) or RT+UA groups (n=8 per group). Participants were trained according to the RT program (60~80% of 1 repetition, 6 times/week), and the UA group was additionally given UA supplementation (450 mg/day) for 8 weeks. Blood samples were obtained before and after intervention, and cortisol, BNP, myoglobin, CK, CK-MB, and LDH levels were analyzed. Subjects who underwent RT alone showed no significant change in body composition and markers of skeletal muscle damage, whereas RT+UA group showed slightly decreased body weight and body fat percentage and slightly increased lean body mass, but without statistical significance. In addition, UA supplementation significantly decreased the BNP, CK, CK-MB, and LDH levels (p<0.05). In conclusion, UA supplementation alleviates increased skeletal muscle damage markers after RT. This finding provides evidence for a potential new therapy for resistance-trained men.

Efeitos do treinamento e de uma prova de triathlon em indicadores de lesão muscular e inflamação / Effects of the training season and a half-ironman in muscle damage and inflammation indicators / Efectos del entrenamiento y una prueba de triatlón en los indicadores de lesiones musculares e inflamación

Resumo Com o objetivo de verificar a dinâmica de marcadores de lesões musculares e da resposta inflamatória aguda produzidas pelo treinamento e por uma prova de meio ironman em atletas de triathlon durante 12 semanas de treinamento, no presente estudo foram avaliadas as alterações musculares e inflamatórias produzidas pelo treinamento e por um meio-ironman em 12 atletas. Amostras de sangue foram coletadas no início do programa de treinamento (M-1), após 10 semanas de preparação (M-2) e após a competição (M-3). Foram avaliadas as atividades da creatina quinase (CK), lactato desidrogenase (LDH), concentração de IL-6, IL-10, proteína C reativa (PCR) e cortisol (C). Foram detectados aumentos em M-3 para a CK (M-1 = 22,25 ± 36,08 UI/L, M-2 = 20,80 ± 42,82 e M-3 = 234,5 ± 135,59 UI/L), LDH (41,71 ± 18,98 U/L, 19,87 ± 16,17 e 191 ± 102,47), PCR (8,42 ± 4,13 mg/L, 5,77 ± 3,54 e 7,62 ± 4,87), IL-6 (77,09 ± 27,86 pg/mL, 93,39 ± 65,2 e 228,48 ± 97,61), IL-10 (88,49 ± 26,36 pg/mL, 89,56 ± 37,99 e 193,31 ± 92,77) e C (14,6 ± 5,92 µg/mL, 23,96 ± 6,44 e 37,47 ± 3,58). A partir desses resultados, conclui-se que os atletas apresentaram aumento dos indicadores de lesões musculares e inflamação apenas após a competição, o que ilustra o efeito agudo dessa prova sobre o organismo desses atletas.

Abstract Aiming to verify the muscle damage and acute inflammatory indicators produced by training and a half-ironman competition in triahlon athletes during twelve weeks of training, we investigated possible muscle changes and inflammatory responses due to the triathlon training and competition in 12 athletes. Blood samples were collected in the beginning of the training (M-1), after 10 weeks of training (M-2) and after the competition (M-3). The activity of CK, LDH, concentration of IL-6, IL-10, C Reactive Protein (PCR) and Cortisol (C) were studied. Changes in CK (M-1= 22,25 ± 36,08 UI/L, M-2= 20,80 ± 42,82 and M-3= 234,5 ± 135,59 UI/L), LDH (41,71 ± 18,98 U/L, 19,87 ± 16,17 and 191 ± 102,47), PCR (8,42 ± 4,13 mg/L, 5,77 ± 3,54 and 7,62 ± 4,87), IL-6 (77,09 ± 27,86 pg/mL, 93,39 ± 65,2 and 228,48 ± 97,61), IL-10 (88,49 ± 26,36 pg/mL, 89,56 ± 37,99 and 193,31 ± 92,77) and C (14,6 ± 5,92 µg/mL, 23,96 ± 6,44 e 37,47 ± 3,58) were found in M-3. From these results, it is possible to conclude that the athletes showed a significant increase of muscle damage and inflammation indicators just after the competition, ilustrating the acute effects of the half-ironman on the organism of these athletes.

Resumen Con el fin de verificar los marcadores dinámicos de lesión muscular y la respuesta inflamatoria aguda producida por el entrenamiento y una prueba de medio ironman en atletas de triatlón durante 12 semanas de formación, hubo cambios inflamatorios y musculares producidos por el entrenamiento y medio ironman en 12 atletas. Las muestras de sangre se recogieron al comienzo de la sesión de entrenamiento (M-1), después de 10 semanas de preparación (M-2) y después de la competición (M-3). Se estudiaron las actividades de creatina-cinas (CK), lactato-deshidrogenasa (LDH), la concentración de interleucina 6 y 10 (IL-6 e IL-10), proteína C-reactiva (PCR) y cortisol (C). Se revelaron cambios en M-3 de la CK (M-1 = 22,25 ± 36,08 UI/l, M-2 = 20,80 ± 42,82 y M-3 = 234,5 ± 135,59 UI/l), LDH (41,71 ± 18,98 U/l, y 19,87 ± 16,17 y 191 ± 102,47), PCR (8,42 ± 4,13 mg/l, 5,77 ± 3,54 y 7,62 ± 4,87), IL-6 (77,09 ± 27,86 pg/ml, 93,39 ± 65,2 y 228,48 ± 97,61), IL-10 (88,49 ± 26,36 pg/ml, 89,56 ± 37,99 y 193,31 ± 92,77) y C (14,6 ± 5,92 mg/ml, 23,96 ± 6,44 y 37,47 ± 3,58). A partir de estos resultados se concluye que los indicadores mostraron aumento de la inflamación y lesiones musculares justo después de la competición, lo que ilustra los efectos agudos de esta prueba sobre el organismo de estos atletas.