Stress fractures

ABSTRACT Stress fractures (SF) represent 10%-20% of all injuries in sport medicine. An SF occurs when abnormal and repetitive loading is applied on normal bone: The body cannot adapt quickly enough, leading to microdamage and fracture. The etiology is multifactorial with numerous risk factors involved. Diagnosis of SF can be achieved by identifying intrinsic and extrinsic factors, obtaining a good history, performing a physical exam, and ordering laboratory and imaging studies (magnetic resonance imaging is the current gold standard). Relative energy deficiency in sport (RED-S) is a known risk factor. In addition, for women, it is very important know the menstrual status to identify long periods of amenorrhea in the past and the present. Early detection is important to improve the chance of symptom resolution with conservative treatment. Common presentation involves complaints of localized pain, with or without swelling, and tenderness on palpation of bony structures that begins earlier in training and progressively worsens with activity over a 2- to 3-week period. Appropriate classification of SF based on type, location, grading, and low or high risk is critical in guiding treatment strategies and influencing the time to return to sport. Stress injuries at low-risk sites are typically managed conservatively. Studies have suggested that calcium and vitamin D supplementation might be helpful. Moreover, other treatment regimens are not well established. Understanding better the pathophysiology of SFs and the potential utility of current and future bone-active therapeutics may well yield approaches that could treat SFs more effectively.

Regulatory effect of curcumin on renal apoptosis and its mechanism in overtraining rats / 中国应用生理学杂志

OBJECTIVE@#To study the effects and mechanisms of curcumin alleviating oxidative stress induced by overtraining and inhibiting renal apoptosis in rats.@*METHODS@#Male Wistar rats of 7 weeks old were divided into control group (C group, 12), overtraining group (OM group, 11), curcumin + overtraining group (COM group, 14). Group C did not undergo any exercise intervention. Rats in OM group and COM group underwent 8-week incremental load swimming training. During the training, the COM group was treated with curcumin at the dose of 200 mg/(kg·d) in the volume as 5 ml/kg by intragastric administration, and the other groups was treated with an equal volume of 0.5% carboxymethylcellulose. Twenty-four hours after the last training, renal histopathological changes were observed by light microscopy, related biochemical indicators in blood and renal tissue were detected.@*RESULTS@#The results showed that after 8 weeks of incremental load swimming training, the renal tissue structure of group C was normal under light microscope; histopathological changes were observed in OM group; COM group was significantly relieved compared with OM group. Compared with group C, serum levels of corticosterone (Cor), creatinine (Cr) and blood urea nitrogen (BUN) in OM group were increased (0.05), while the expression of heme oxygenase-1 (HO-1) was decreased (<0.05), total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) activity were decreased (<0.01), malondialdehyde (MDA) concentration was increased (<0.01); the renal apoptosis was increased (<0.01), the expression of anti-apoptotic B cell lymphoma-2 protein (Bcl-2) was decreased (<0.01), and the expression of proapoptotic Bcl-2 associated X protein (Bax) was increased (<0.01). Compared with the OM group, Cor level was decreased (<0.01) in the COM group, T level was increased (<0.01), Cr and BUN levels were lower (<0.05); the expression of Nrf2 and HO-1 were increased (<0.05), T-AOC and SOD activity were increased (<0.01), MDA concentration was decreased (<0.05); the renal apoptosis was decreased (<0.05), the expression of Bcl-2 was increased (<0.05), and the expression of Bax was decreased (<0.01). The trend of testosterone/corticosterone ratio between groups was consistent with testosterone change, and the change trend of Bcl-2/Bax ratio was consistent with the change of Bcl-2.@*CONCLUSIONS@#The 8-week incremental load swimming training triggered excessive training in rats, aggravated oxidative stress and accelerated renal apoptosis, leading to pathological changes and dysfunction of kidney. Curcumin can up-regulate expression of Nrf2 and HO-1, effectively alleviates oxidative stress induced by overtraining, thereby increasing Bcl-2 expression, decreasing Bax expression, inhibiting renal apoptosis and protecting renal tissue structure and function properly.

Hypothalamic endoplasmic reticulum stress of overtrained mice after recovery

Abstract AIMS knowing the relationship between endoplasmic reticulum (ER) stress and inflammation and based on the fact that downhill running-based overtraining (OT) model increases hypothalamus levels of some pro-inflammatory cytokines, we verified the effects of three OT protocols on the levels of BiP, pIRE-1 (Ser734), pPERK (Thr981), pelF2alpha (Ser52), ATF-6 and GRP-94 proteins in the mouse hypothalamus after two weeks of recovery. METHODS the mice were randomized into control (CT), overtrained by downhill running (OTR/down), overtrained by uphill running (OTR/up) and overtrained by running without inclination (OTR) groups. After 2-week total recovery period (i.e., week 10), hypothalamus was removed and used for immunoblotting. RESULTS the OTR/down group exhibited high levels of BiP and ATF6. The other OT protocols showed higher levels of pPERK (Th981) and pelf-2alpha (Ser52) when compared with the CT group. CONCLUSION the current results suggest that after a 2-week total recovery period, the overtrained groups increased partially their ER stress protein levels, but without hypothalamic inflammation, which characterizes a physiological condition related to an adaptation mechanism.(AU)

Nonfunctional overreaching and hepatic adaptations of APPL1 and APPL2

Abstract AIMS Previously, we verified that overtrained mice upregulated the TRB3 levels, its association with Akt, and the hepatic concentrations of glycogen. It is known that APPL1 can limit the interaction between TRB3 and Akt, playing an important role in the glucose homeostasis. Thus, we verified the effects of three overtraining protocols on the hepatic levels of APPL1 and APPL2. METHODS Rodents were divided into control (CT), overtrained by downhill running (OTR/down), overtrained by uphill running (OTR/up) and overtrained by running without inclination (OTR). The hepatic contents of APPL1 and APPl2 were measured by the immunoblotting technique. RESULTS Significant elevation of APPL1 observed in the OTR/down and OTR/up groups, as well as the tendency of increase (p=0.071) observed in the OTR group. CONCLUSION These results indicate that this particular protein is likely to participate in the glucose homeostasis previously observed in response to these OT protocols.(AU)

Pre-competitive physical training and markers of performance, stress and recovery in young volleyball athletes / Treinamento físico pré-competitivo e marcadores de desempenho, estresse e recuperação em jovens atletas de voleibol

The aim of this study was to analyze the effect of physical training during a pre-competition period on power and explosive strength endurance of the lower limbs, stress and recovery in young volleyball athletes. Seven male athletes (15.8 ± 0.5 years, 186.1 ± 6.6 cm, 75.9 ± 1.8 kg) of an Under-16 volleyball team were trained during a pre-competition period of 4 weeks. The internal training load (ITL) was monitored by the session RPE method. The participants performed a countermovement jump test (CMJ) and an intermittent jump test of four sets of 15 seconds (IJT) on the first day of training (baseline) and on the last day of the 2nd (post-week 2) and 4th week (post-week 4). The RESTQ-Sport Questionnaire was applied at baseline and on the last day of the 2nd, 3rd and 4th week (post-weeks 2, 3 and 4). No difference was observed in ITL (p>0.05). CMJ performance increased gradually from baseline to post-week 2 and from post-week 2 to post-week 4 (p<0.05). The average power in the first 15 seconds and average power of the four sets of 15 seconds of the IJT were higher in post-week 4 compared to baseline (p<0.01). Scores on the Fatigue and Injury scales of the RESTQ-Sport changed during training (p<0.05). We conclude that training applied during the pre-competitive period provided increments in CMJ performance and explosive strength endurance, and the changes in the RESTQ-Sport suggest that the athletes had adequate levels of stress and recovery.

O objetivo deste estudo foi analisar o efeito do treinamento físico aplicado em um período pré-competitivo na potência e na resistência de força explosiva de membros inferiores, no estresse e na recuperação de jovens atletas de voleibol. Sete atletas (15,8 ± 0,5 anos, 186,1 ± 6,6cm, 75,9 ± 1,8kg) de uma equipe de voleibol sub-16, do sexo masculino, foram treinados durante um período pré-competitivo de quatro semanas. A carga interna de treinamento (CIT) foi monitorada pelo método PSE da sessão. Testes de salto vertical com contramovimento (CMJ) e de natureza intermitente, de quatro séries de 15 segundos (TSVI), foram avaliados no 1º dia de treinamento (linha de base), no último dia da 2ª (pós-semana 2) e da 4ª semana (pós-semana 4). O Questionário RESTQ-Sport foi aplicado na linha de base, no último dia da 2ª, 3ª e 4ª semanas (Pós-semana 2, 3 e 4). A CIT não foi diferente (p>0,05). O CMJ aumentou no pós-semana 2, comparado com a linha de base e no pós-semana 4, comparado com o pós-semana 2 (p<0,05). A média de potência nos 15 segundos iniciais e a média de potência das quatro séries de 15 segundos do TSVI foram maiores no pós-semana 4, comparado à linha de base (p<0,01). As escalas Fadiga e Lesões do RESTQ-Sport se alteraram ao longo do treinamento (p<0,05). Conclui-se que o treinamento aplicado durante o período pré-competitivo proporcionou incrementos no CMJ e no TSVI, e as alterações no RESTQ-Sport sugerem que os atletas apresentaram níveis adequados de estresse e recuperação.

Overtraining increases the strength of equivalence relations

The present study investigated whether overtraining of the conditional discriminations that are the prerequisites of equivalence class formation strengthens the relations among stimuli in an equivalence class. Two groups of college students formed equivalence classes that consisted of faces that expressed emotions (A) and arbitrary stimuli (B, C, D, and E). The overtraining group had twice as many training trials as the regular training group. For participants who formed equivalence classes, relational strength was evaluated by the generalization of expressed emotions from the A to the D stimuli, which was measured using a semantic differential. An untrained control group showed semantic differential scores that were positive for happy faces, negative for angry faces, and neutral for the D stimuli. For the experimental groups, the D stimuli, when included in equivalence classes, produced scores that were similar to those produced by the equivalent faces. The overtraining group, however, had average values closer to the values of the faces than the regular training group. These results indicate that the amount of training is an experimental parameter that influences the strength of relations between stimuli that are found to be equivalent in matching-to-sample tests...

Effects of a multivitamin/multimineral supplement on young males with physical overtraining: a placebo-controlled, randomized, double-blinded cross-over trial / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the effects of vitamin-mineral supplement on young males with physical overtraining.</p><p><b>METHODS</b>Two hundred and forty male Chinese field artillery personnel who undertook large scale and endurance military training and were on ordinary Chinese diet were randomized to receive a multivitamin/multimineral supplement or a placebo for 1 week. After a 1-week wash-out period, a cross-over with 1 week course of a placebo or multivitamin/multimineral supplement was conducted. Blood and urine samples were analyzed for adrenal, gonadal and thyroid hormones. In addition, cellular immune parameters (CD3+, CD3+CD4+, CD3+CD8+, CD4/CD8, CD3-CD56+, CD3-CD19+) were examined and psychological tests were performed before and after the training program and nutrition intervention.</p><p><b>RESULTS</b>After a large scale and endurance military training, the participants showed significantly increased thyroid function, decreased adrenal cortex, testosterone and immunological function, and significantly increased somatization, anger and tension. Compared to placebo, multivitamin/ multimineral intervention showed significant effects on functional recovery of the pituitary - adrenal axis, pituitary-gonadal axis, pituitary- thyroid axis and immune system as well as psychological parameters.</p><p><b>CONCLUSION</b>High-intensity military operations have significant impacts on the psychology, physical ability and neuroendocrine-immune system in young males. Appropriate supplementation of multivitamin/multimineral can facilitate the recovery of the psychology, physical ability and neuroendocrine-immune system in young males who take ordinary Chinese diet.</p>

Analysis of the renal histopathological changes on the human of overtraining induced acute renal injury / 中国综合临床

Objective To investigate the renal histopathological changes of over training induced acute renal injury in human being.Methods Eight patients treated in our hospital admitted overtraining were observed retrospectively about their clinical and pathological data,including clinical features,laboratory tests and pathological examinations.Results Eight patients with acute kidney injury after overtraining,manifested as urine occult blood positive in 2 cases,3 cases of urinary protein,urinary occult blood and urine protein were positive in 3 cases.Five cases of renal dysfunction,manifested as creatinine,urea nitrogen,uric acid significantly increased; renal ultrasound non-specific changes,manifested as increased echogenicity of the cortex.2 cases of renal pathology glomerular ischemic; Two cases of renal interstitial mild edema,five cases of inflammatory cell infiltration; Three cases of renal tubular epithelial vacuolar degeneration,2 cases of tubular atrophy,4 cases of renal tubular epithelial brush border loss,see intraluminal protein casts can be seen,1 case of calcium deposition.Conclusion The acute renal injury can be induced by overtraining.Kidney pathology ischemic is the most important change and renal tubular show most sensitive features of ischemic.In addition,inflammatory response and striated muscle damage were also induced because of overtraining.

Exercício físico, processo inflamatório e adaptação: uma visão geral / Physical exercise, inflammatory process and adaptive condition: an overview

O exercício físico induz inflamação, evento que ocorre para promover o reparo e remodelamento tecidual após o trauma. A ativação do processo inflamatório é local e sistêmico, valendo-se para isso de diversas células e componentes secretados. O objetivo é restabelecer a homeostasia orgânica após uma única sessão ou após diversas sessões de exercícios. A resposta de fase aguda consiste de ações integradas entre leucócitos, citocinas, proteínas de fase aguda, hormônios e outras moléculas sinalizadoras que controlam a resposta tanto a uma sessão de exercícios como também direcionam as adaptações decorrentes do treinamento. Nessa revisão, apresentaremos um panorama geral sobre inflamação e exercício físico, e os dados na literatura sobre marcadores de inflamação em resposta a diferentes protocolos experimentais. Os resultados obtidos apontam respostas distintas sobre o processo inflamatório em relação aos efeitos agudos ou crônicos dos exercícios. De forma geral, uma única sessão de exercício físico intenso induz um estado pró-inflamatório, representado por leucocitose transitória, em decorrência de neutrofilia, monocitose e linfocitose, seguida de supressão parcial da imunidade celular. Também têm sido observados aumentos nas concentrações séricas da enzima creatina quinase, proteína C-reativa e moléculas de adesão celular, além do aumento na secreção de cortisol e citocinas. Já o treinamento físico sistematizado pode levar a um estado anti-inflamatório local e sistêmico. Esse ambiente anti-inflamatório viabilizaria a adaptação e, ao mesmo tempo, protegeria o organismo contra o desenvolvimento de patologias inflamatórias crônicas e dos efeitos nocivos do overtraining, quando parece prevalecer um estado pró-inflamatório e pró-oxidante crônico e sistêmico.

Physical exercise induces inflammation, a physiological response that is part of immune system activity and promotes tissue remodeling after exercise overload. The activation of the inflammatory process is local and systemic and is mediated by different cells and secreted compounds. The objective is to reestablish organ homeostasis after a single bout of exercise or after several exercise sessions. The acute-phase response involves the combined actions of activated leukocytes, cytokines, acute-phase proteins, hormones, and other signaling molecules that control the response to an exercise session and guide the adaptations resulting from training. This review provides an overview of the inflammatory process related to exercise and literature data regarding markers of inflammation in response to different experimental protocols. The results obtained indicate distinct inflammatory responses to acute and chronic exercise. In general, acute exercise induces a proinflammatory response characterized by transient leukocytosis (neutrophilia, monocytosis, and lymphocytosis), followed by a partial cellular immunosuppressive state. An increase in serum concentrations of creatine kinase, C-reactive protein and cell adhesion molecules is also observed, in addition to an increased secretion of cortisol and cytokines. In contrast, chronic exercise results in a local and systemic anti-inflammatory response that promotes tissue adaptation and protects the organism against the development of chronic inflammatory diseases and against the effects of non-functional overtraining, a condition in which a systemic and chronic proinflammatory and pro-oxidant state seems to prevail.

Effects of anisodamine on apoptosis in cardiomyocytes and inflammatory response in overtrained rats / 中华麻醉学杂志

Objective To evaluate the effects of anisodamine on apoptosis in cardiomyocytes and inflammatory response in overtrained rats. Methods Twenty-four male Wistar rats, weighing 200-220 g, were randomly divided into 3 groups ( n = 8 each) : control group (group C) , overtraining group (group O) , anisodamine group (group A) . The model of overtraining-induced acute heart injury was established by exhausting swimming. Anisodamine 10 mg/kg was given intraperitoneally 20 min before overtraining in group A. Blood samples were taken at 6 h after overtraining for measurement of serum CK-MB activity. The rats were then sacrificed and myocardial tissues taken for determination of TNF-α content and NF-κB activity (by immunohistochemistry) . The apoptosis rate was detected by flow cytometry. Results The CK-MB activity, apoptosis rate, TNF-α content and NF-κB activity were significantly higher at 6 h after overtraining in groups O and A than in group C, while lower at 6 h after overtraining in group A than in group O ( P < 0.05) . Conclusion Anisodamine can inhibit apoptosis in cardiomyocytes by reducing inflammatory response in overtrained rats.

Overtraining induces renal tubular cells apoptosis through activating caspase-related signal pathway by impairing the balance of Bax and Bcl-2 in exhaustive swimming rats / 中华肾脏病杂志

Objective To observe the expression changes of renal tissue Bax,Bcl-2 and caspase-3,to wxamine the correlation between the ratio of Bax to Bcl-2,caspase-3 and renal tubular cells apoptosis,and to investigate the role of caspase-related signal pathway.Methods Forty-eight male Wistar rats were randomly divided into three groups: control (CN,n=8),exhaustive swimming (ES,n=24) and inula britannica (IB,n=16) group.The rats of CN were quiet without swimming.The rats of ES swam to exhaustive state and were sacrificed at immediately(ESI),6 hour (ES 6 h) and 24 hour (ES 24 h) after exhaustive swimming respectively.The rats of IB took orally inala britannica at the dose of 25 ml/kg body weight at 24 h before swimming and then swam to exhaustive state.The rats of IB group were sacrificed at 6 hour (IB 6 h) and 24 hour (IB 24 h)after exhaustive swimming.The animal model of overtraining-induced acute kidney injury was developed by exhaustive swimming.The renal cell apoptosis was measured by the method of TUNEL.The expressions of Bax,Bcl-2,caspase-3 in renal tissue were observed by immunohistochemistry.The expression of caspase-3 protein was examined by Western blotting.The correlation between the ratio of Bax to Bcl-2 and caspase-3 was analysed by Pearson method,and the correlation between the ratio of Bax to Bcl-2,caspase-3 and renal tubular cell apoptosis was analysed by Spearman method.Results The number of renal tubular apeptotic cells was increased progressively in ESI to ES 24 h rats by TUNEL (P＜0.05).Immunohistochemistry staining showed that the ratio of Bax to Bcl-2 and caspase-3 in renal tubular cells were increased progressively at 0 h,6 h and 24 h after exhaustive swimming compared with control group (P＜0.05).The change of renal tissue caspase-3 was also revealved by Western blotting analysis.The ratio of Bax to Bcl-2 and caspase-3 in renal tubular cell was correlated positively (r=0.865,P＜0.05),The ratio of Bax to Bcl-2,and caspase-3 was also correlated positively to renal tubular cell apoptosis (r=0.674,r=0.837,P＜0.05) in ES rats.Pretreatment with inula britannica inhibited the up-regulation of the ratio of Bax to Bcl-2,caspase-3 and cell apoptosis in renal tubular cell induced by exhaustive swimming.Conclusion Overtraining can induce renal tubular cells apoptosis through activating caspase-related signal pathway by impairing the balance of Bax and Bcl-2,which may be one of the important molecular mechanisms of overtraining-induceed renal tubular cells apoptosis.

(Mal) adaptações metabólicas ao treinamento contínuo: concepções não consensuais de terminologia e diagnóstico / Metabolic (mal) adaptations to training continuum - misconceptions of terminology and diagnosis

Altos desempenhos esportivos demandam treinamentos pesados necessários ao estímulo adaptativo específico a cada esporte. A elevada carga de treino é geralmente acompanhada de discreta fadiga e reduções agudas no desempenho, mas caso acompanhada de períodos apropriados de recuperação, resulta em supercompensação metabólica ao treinamento, refletida como aumento na capacidade aeróbica e/ou força muscular. Visto como contínuo, os processos de intensificação do treinamento e o estresse relacionado à supercompensação, o aumento da sobrecarga ou do estresse poderá, em algum momento, acarretar a quebra da homeostase e a queda temporária da função (supra-alcance - OR ou supra-alcance funcional - FOR). Quando a sobrecarga excessiva de treinamento é combinada com recuperação inadequada há instalação do estado de supratreinamento (OT) ou supra-alcance não funcional (NFOR). O OT excede o OR, cujo pico é também o limiar do OT resultando em desadaptações fisiológicas e queda crônica do desempenho físico. A forma crônica de desadaptação fisiológica ao treinamento físico é chamada de síndrome do supertreinamento (OTS). A própria expressão da síndrome denota a etiologia multifatorial do estado e reconhece que o exercício não é necessariamente seu único fator causal. O diagnóstico de OTS é baseado na recuperação ou não do desempenho. Não há biomarcador objetivo para OTS. A distinção entre OTS e NFOR (supratreinamento extremo) é dependente de desfecho clínico e exclusão diagnóstica de doenças orgânicas, mais comuns na OTS. Também a diferença entre OR e OT é sutil e nenhum de seus marcadores bioquímicos pode ser universalizado. Não há evidências confirmatórias que OR evolui para OT ou que os sintomas de OT são piores dos que os de OR. Apenas pela fadiga aguda e queda de rendimento experimentada em sessões isoladas de treinamento, não é possível diferenciar presentemente os estados de OR e OT. Isto é devido, parcialmente, à variabilidade das respostas individuais ao treinamento e...

Sports top-level performance requires heavy training loads that provide a stimulus to sport-specific adaptation. Competitive training involving high workload is generally accompanied by minor fatigue and acute performance reduction, but when followed by appropriate recovery periods results in training-metabolic supercompensation reflected as increase in aerobic capacity and muscular strength. When the intensified training process leading to supercompensation and related-stress is seen as a continuum, the increased stress or overload might result in disruption of homeostasis and temporary decrease in function (overreaching - OR or functional overreaching - FOR). When excessive overload is combined with inadequate recovery, a state of overtraining (OT) or non-functional overreaching (NFOR) is installed. OT exceeds OR and the OR peak is also the OT threshold, resulting in stark physiological maladaptations and chronically reduced exercise performance. The chronic form of physiological maladaptation to training is called overtraining syndrome (OTS). The expression of the syndrome emphasizes the multifactorial etiology of the state and acknowledges that exercise (training) is not necessarily the sole causative factor. There is no objective biomarker for OTS besides the diagnosis based on performance recovery. Other distinctions between NFOR (extreme OT) and OTS depend on clinical outcome and exclusion diagnosis of organic diseases more common in OTS. Additionally, the difference between OR and OT is subtle and none of their biochemical markers should be considered universal. There is no evidence to confirm that OR will develop into OT or that OT symptoms are worse than those of OR. It is presently not possible to differentiate OR and OT states from the acute fatigue and decreased performance experienced from isolated training sessions. This situation is partially due to the variability of individual responses to training and to a lack of both diagnostic tools and ...

Absence of the predisposing factors and signs and symptoms usually associated with overreaching and overtraining in physical fitness centers

OBJECTIVE: The aim of this study was to evaluate the occurrence of the well-known predisposing factors and signs and symptoms usually associated with either overreaching or overtraining syndrome in physical fitness centers in São Paulo City, Brazil. METHOD: A questionnaire consisting of 13 question groups pertaining to either predisposing factors (1-7) or signs and symptoms (8-13) was given to 413 subjects. The general training schedule of the volunteers was characterized by workout sessions of 2.18 ± 0.04 h for a total of 11.0 ± 0.3 h/week for 33 ± 2 months independent of the type of exercise performed (walking, running, spinning, bodybuilding and stretching). A mean score was calculated ranging from 1 (completely absent) to 5 (severe) for each question group. A low occurrence was considered to be a question group score lower than 4, which was observed in all 13 question groups. RESULTS: The psychological evaluation by POMS Mood State Questionnaire indicated a normal non-inverted iceberg. The hematological parameters, creatine kinase activity, cortisol, total testosterone and free testosterone concentrations were within the normal ranges for the majority of the volunteers selected for this analysis (n = 60). CONCLUSION: According to the questionnaire score analysis, no predisposing factors or signs and symptoms usually associated with either overreaching or overtraining were detected among the members of physical fitness centers in São Paulo City, Brazil. This observation was corroborated by the absence of any significant hematological or stress hormone level alterations in blood analyses of the majority of the selected volunteers (n = 60).

Overtraining induces renal cell apoptosis partly through inflammatory signal pathway in exhaustive swimming rats / 中华肾脏病杂志

Objective To observe the changes in the expression of renal tissue TNF-α , NF-κB and the interrelation to renal cell apoptosis, and their influences of Inula Britannica(an inhibitor of inflammatory signal pathway) in exhausted swimming rats, and to investigate the role of inflammatory signal pathway. Methods Forty-eight male Wistar rats were randomly divided into three groups: control group (CN, n=8), exhaustive swimming group (ES, n=24) and Inula Britannica group (IB, n=16). The rats of CN were quiet without swimming. The rats of ES swam to exhaustion and were sacrificed at immediately (ESI, n=8), 6 hour (ES 6 h, n=8) and 24 hour (ES 24 h, n=8) after exhanstiing swimming. The rats of IB group took orally Inula Britannica at the dose of 25 ml/kg body weight at 24 h before swimming and then swam to exhaustive state. The rats of IB group were sacrificed at 6 hour (IB 6 h, n=8) and 24 hour (IB 24 h, n=8) after exhaustiing swimming. The renal cell apoptosis was measured by the method of terminal-deoxynucleotidyl transferase mediated d-UTP nick end labeling (TUNEL). The expression of TNF-α in renal tissue was examined by immunohistochemistry. The changes of NF-κB in renal tissue were measured by flow cytometry and immunnhistochemistry. The interrelation between TNF-α and NF-κB was analyzed by Pearson method, and the interrelation between TNF-α, NF-κB and renal tissue cell apoptosis was analyzed by Spearman method. Resulls The number of renal tissue apoptotic cells was increased progressively from ESI to ES 24 h rats (P <0.05). Immunohistochemistry staining showed that the positive expressions of renal tissue TNF-α and NF-κB were increased progressively at 0 h (0.136±0.009, 0.129±0.011), 6 h (0.171±0.011, 0.166± 0.009) and 24 h (0.229±0.008, 0.218±0.019) after exhaustiing swimming in ES compared with control group (0.109±0.010, 0.095±0.010) ( all P<0.05). The similar changes of renal tissue NF-κB was also revcalved by flow cytometry. The expression of TNF-α was positively correldted with NF-κB (r=0.955, P<0.01 ), and renal cell apoptosis was also positively correlated with TNF-α and NF-κB (r =0.953, r=0.939, P<0.01) in ES rats. Pretreatment with Inula Britannica, inhibited the up-regulation of expressions of renal tissue TNF-α (6 h:0.142±0.012, 24 h:0.130±0.010) and NF-κB (6 h:0.138±0.010, 24 h:0.136±0.011 ) induced by exhausting swimming. Conclusion Overtraining can induce the up-regulating expressions of renal tissue TNF-α and NF-κB, and Inula Britannica can partly counter the above changes in exhaustied swimming rats, which may be one important mechanisms of overtraining-induced renal tissue cell apoptosis and the anti- apoptosis effect of Inula Britannica.

Níveis de beta-endorfina em resposta ao exercício e no sobretreinamento: [revisão] / Levels of beta-endorphin in response to exercise and overtraining: [review]

O sobretreinamento (ST) é um fenômeno esportivo complexo e multifatorial; e atualmente não existe nenhum marcador independente que possa diagnosticá-lo. Interessantemente, alguns sintomas do ST apresentam relação com os efeitos da b-endorfina (b-end1-31). Alguns de seus efeitos são importantes para o treinamento, como analgesia, maior tolerância ao lactato e euforia do exercício. Esses efeitos podem ser revertidos por destreinamento ou por ST, ocasionando diminuição no desempenho, redução da tolerância à carga e depressão. O exercício físico é o principal estímulo da b-end1-31, pois sua secreção é volume/intensidade dependente, tanto para exercícios aeróbios quanto anaeróbios. No entanto, o treinamento excessivo pode diminuir suas concentrações, alterando assim seus efeitos benéficos para o treinamento. Portanto, a b-end1-31 poderia ser utilizada como um marcador adicional de ST, principalmente porque seus efeitos apresentam extensa relação com os sintomas do ST.

Overtraining (OT) is a complex and multifactorial sport phenomenon, and there is no independent marker that can diagnose OT. Interestingly, some symptoms of OT are related to b-endorphin (b-end1-31) effects. Some of its effects, such as analgesia, increasing lactate tolerance, and exercise-induced euphoria, are important for training. These effects can be reverted by detraining or OT, which may cause decrease in performance, reduced load tolerance, and depression. The main stimulus for b-end1-31 secretion is to exercise because its secretion is volume/intensity dependent for both aerobic and anaerobic exercise. Excess training, however, may reduce b-end1-31 concentrations, thus altering its beneficial effects. Therefore, b-end1-31 could be used as an additional OT marker, mainly because its effects are strongly related to OT symptoms.

Effect of Overtraining on Skeletal Muscle Glycogen,AMPK Activity and Sarcolemma GLUT4 Protein Content in Rats / 中国运动医学杂志

Objective The purpose of the present study was to observe the muscle glucose metabolism by determining the changes in sarcolemma GLUT4 protein content and muscle AMPK activity in overtraining rats.Methods Twenty-seven SD rats were randomly divided into group A(sedentary),group B(underwent endurance exercise 60 minutes/day)and group C(underwent endurance exercise 120 minutes/day).Both exercise groups trained 6 days/wk for 9 weeks.Muscle glycogen,sarcolemma GLUT4 contents and muscle AMPK activity were determined after the 9-week training.Results Sarcolemma GLUT4 content and muscle AMPK activity increased,muscle glycogen contents tended to rise in group B as compared with that in group A.Sarcolemma GLUT4 content and muscle AMPK activity decreased,but muscle glycogen contents were equivalent in group C as compared with that in group B.Conclusion Muscle AMPK activity deceased,and the translocation of GLUT4 protein was inhibited in the overtraining rats.The results could not support a glycogen depletion hypothesis.

The role of endothelin-1 and angiotensin Ⅱ in acute kidney injury due to over-exertion in rats / 解放军医学杂志

Objective To study the role of endothelin-1 (ET-1) and angiotensin Ⅱ (AngⅡ) in over-exertion induced acute kidney injury (OTIAKI) by observing the changes in ET-1 and AngⅡ contents in plasma and renal tissue and their relationship with OTIAKI in exhausted rats. Methods 40 male Wistar rats were randomly divided into two groups: control group (CN, n=8) and exhaustion group (ES, n=32). The exhaustion group, depending on the recovery time after exhaustion, was further divided into 4 subgroups (8 each): immediate subgroup (ESI), 6h after exhaustion subgroup (ES 6h), 12h after exhaustion subgroup (ES 12h) and 24h after exhaustion subgroup (ES 24h). The animal model of OTIAKI was reproduced by exhausting swimming, while the rats in control group were not forced to swim. The contents of serum urea (Ur) and creatinine (Cr) in each group were serially measured. The renal specimens were observed with a light microscope to study their morphologic changes. Renal cell apoptosis was detected using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay. The contents of ET-1 and AngⅡ in plasma and renal tissue were measured by radio-immunoassay (RIA). The correlation between the content of ET-1 and the levels of serum Ur and Cr were was analyzed by Pearson method, and the correlation between the content of AngⅡ in renal tissue and cell apoptosis was analyzed by Spearman method. Results The levels of serum Ur and Cr were significantly increased in ESI group (P

Gene regulation of renal cell apoptosis and effect of anisodamine on overtrained rat by exhausting swimming / 解放军医学杂志

Objective To study the expressions of apoptosis related genes Bcl-2 and Bax proteins in rat's renal tissue and the relationship between the ratio of Bcl-2/Bax and renal cell apoptosis induced by overtraining,and observe the effect of anisodamine on the expression of genes Bcl-2 and Bax in exhausted rats.Methods The animal model of acute kidney injury induced by exhausting swimming was reproduced.Forty eight male Wistar rats were randomly assigned into sedentary control group(CN,n=8),exhausting swimming group(immediate,6 hours and 24 hours after exhausting swimming,ESI,ES6h and ES24h,8 each),Anisodamine group(6 hours and 24 hours after exhausting swimming,AD6h and AD24h,8 each).The expressions of Bcl-2 and Bax were detected by immunohistochemical staining and image analyzer.The correlation between the ratio of Bcl-2/Bax and renal cell apoptosis was analyzed.Results The analysis showed that the expression of Bax increased,and of Bcl-2 decreased,the ratio of Bax/Bcl-2 increased remarkably in ESI group compared with CN group(P

Two Case Reports of Overtraining Syndrome with Anemia Successfully Treated with Ryo-kei-jutsu-kan-to / 日本東洋医学雑誌

Ryo-kei-jutsu-kan-to was used to successfully treat two cases of overtraining syndrome with anemia. The first case was an 18-year-old woman. Several years ago, she was diagnosed with iron deficiency anemia, and she took Fe pills intermittently. After university graduation in 1996, she began to experience lightheadedness and general malaise concurrently with increased training of long-distance running. In September of the same year, her anemia worsened, and she was introduced to our department. Administration of Ryo-kei-jutsu-kan-to improved her symptoms, anemia and maximal oxygen uptake. The second case was a 19-year-old woman. She was an office worker and a member of her company's athletic club. She became easily fatigued, and she came to our clinic in December of 1996. Hochu-ekki-to was administered and her fatigue improved. But in the following year she began to feel depressed and lightheaded, and she became anemic after increased increasing her training of long-distance running. Administration of Ryo-kei-jutsu-kan-to improved her symptoms and anemia.

Síndrome do Overtraining / Overtraining syndrome

Os autores fazem uma revisão bibliográfica acerca da etiologia, quadro clínico, critérios diagnósticos e, principalmente, prevenção e tentativas de tratamento da síndrome do overtraining.

In this paper, the authors review the literature regarding to ethiology, clinical presentation, diagnostic criteria and particularly the prevention and the methods of treatment of the overtraining syndrome.