Effect of experimental pulmonary arterial hypertension on renal and bone parameters of rats submitted to resistance exercise training.

Pulmonary arterial hypertension (PAH) is characterized by right ventricular failure and diminished cardiac output, potentially leading to renal and bone impairments. In contrast, resistance exercise training (RT) offers cardiovascular and bone health benefits. This study aimed to assess the impacts of stable PAH induced by monocrotaline (MCT) and RT on renal morphometry, as well as bone morphometry and biomechanical properties in male Wistar rats. Four experimental groups, untrained control (UC, n=7), trained control (TC, n=7), untrained hypertensive (UH, n=7), trained hypertensive (TH, n=7), were defined. After the first MCT or saline injection (20 mg/kg), trained rats were submitted to a RT program (i.e., Ladder climbing), 5 times/week. Seven days later the rats received the second MCT or saline dose. After euthanasia, renal and femoral histomorphometry and femoral biomechanical properties were assessed. PAH reduced renal glomerular area and volume, which was prevented by the RT. While PAH did not harm the femoral morphometry, structural and mechanical properties, RT improved the femoral parameters (e.g., length, percentage of trabeculae and bone marrow, ultimte and yield loads). Experimental stable PAH promotes renal but not bone damages, whereas RT prevents renal deteriorations and improves the femoral morphological and biomechanical properties.

Resistance exercise training benefits pulmonary, cardiac, and muscular structure and function in rats with stable pulmonary artery hypertension.

AIM: We tested the effects of low- to moderate-intensity resistance exercise training (RT) on the structure and function of pulmonary, right ventricle (RV), and skeletal muscle tissues in rats with stable pulmonary artery hypertension (PAH). MAIN METHODS: After the first monocrotaline (MCT; 20 mg/kg) injection, male rats were submitted to a RT program (Ladder climbing; 55-65 % intensity), 5 times/week. Seven days later rats received the second MCT dose. Physical effort tolerance test and echocardiographic examination were performed. After euthanasia, lung, heart, and biceps brachii were processed for histological, single myocyte, and biochemical analysis. KEY FINDINGS: RT improved survival and physical effort tolerance (i.e., maximum carrying load), mitigated the pulmonary artery resistance increase (i.e., TA/TE), and preserved cardiac function (i.e., fractional shortening, ejection fraction, stroke volume and TAPSE). RT counteracted oxidative stress (i.e., CAT, SOD, GST, MDA and NO) and adverse remodeling in lung (i.e., collapsed alveoli) and in biceps brachii (i.e., atrophy and total collagen) tissues. RT delayed RV adverse remodeling (i.e., hypertrophy, extracellular matrix, collagen types I and III, and fibrosis) and impairments in single RV myocyte contractility (i.e., amplitude and velocity to peak and relaxation). RT improved the expression of gene (i.e., miRNA 214) and intracellular Ca2+ cycling regulatory proteins (i.e., PLBser16); and of pathological (i.e., α/ß-MHC and Foxo3) and physiological (i.e., Akt, p-Akt, mTOR, p-mTOR, and Bcl-xL) hypertrophy pathways markers in RV tissue. SIGNIFICANCE: Low- to moderate-intensity RT benefits the structure and function of pulmonary, RV, and skeletal muscle tissues in rats with stable pulmonary artery hypertension.

Effects of voluntary running on the skeletal muscle of rats with pulmonary artery hypertension.

The effects of voluntary running on the skeletal muscle of rats with pulmonary arterial hypertension (PAH) were tested in the present study. PAH was induced in rats by a single injection of monocrotaline (MCT, 60 mg/kg). Rats in the sedentary hypertension (HS) group had their tolerance to physical exertion reduced throughout the experiment, while those in the sedentary control (SC), exercise control (EC), exercise hypertension (EH) and median exercise (EM) groups maintained or increased. Despite that, the muscular citrate synthase activity was not different between groups. The survival time was higher in the EH (32 days) than in the SH (28 days) (p = 0.0032). SH and EH groups showed a lower percentage of muscle fiber and a higher percentage of extracellular matrix compared to control groups (p < 0.0001). However, the EM and EH groups presented higher percentage of muscle fiber and lower percentage of extracellular matrix than SH group (p < 0.0001). Regarding muscular gene expression, the SH and EM groups showed a lower expression of PGC1-α (p = 0.0024) and a higher expression of VEGF (p = 0.0033) compared to SC, while PGC1-α was elevated in the EH. No difference between groups was found for the carbonylated protein levels (p > 0.05), while the TNF-α/IL-10 ratio was augmented in the EH (p = 0.0277). In conclusion, voluntary running augments the proportion of fiber and affects the gene expression of inflammatory and mitochondrial biogenesis' markers in the skeletal muscle of rats with MCT-induced PAH, which benefits their survival and tolerance to physical effort.

Interventions towards barriers to the practice of physical activity in adolescence: A systematic review protocol.

INTRODUCTION: Lack of regular physical activity is recognized as a global public health issue. Three out of every four adolescents do not adhere to physical activity recommendations. Thus, this systematic review will evaluate interventions employed to minimize barriers to physical activity among adolescents. Herein, we present the study protocol. To the best of our knowledge, this will be the first systematic review to assess the interventions implemented to minimize barriers to the practice of physical activity among adolescents. A systematic understanding of the most effective interventions to reduce the barriers to physical activity is essential. METHOD AND ANALYSIS: We will search five databases: two multidisciplinary (Scopus and Web of Science) and three other health-related databases (Embase, SPORTDiscus, and PubMed). The search will be limited to original peer-reviewed articles published in English, with no time restrictions. The search strategy will use MeSH terms and their variations to maximize the search strategy. Two reviewers will independently read the included articles, extract the data, and evaluate the methodological quality using the Grading of Recommendations, Assessment, Development, and Evaluation scale and the risk of bias using the Critical Appraisal Skills Programme checklist and Downs and Black scale. Discrepancies will be resolved by a third reviewer. This systematic review will follow the guidelines outlined in the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses. DISCUSSION: The outcomes of this study are expected to enhance the current understanding of the obstacles to physical activity among adolescents and aid in the development or modification of programs to combat physical inactivity in this population. Consequently, these findings should have a positive impact on current and future adolescent health outcomes. ETHICS AND DISCLOSURE: Ethical approval will not be required for this study as it is an analysis of previously published articles (i.e., secondary data). The results will be published in a peer-reviewed journal. PROSPERO registration: CRD42022382174.

O Treinamento Físico Resistido Atenua as Disfunções Ventriculares Esquerdas em Modelo de Hipertensão Arterial Pulmonar / Resistance Exercise Training Mitigates Left Ventricular Dysfunctions in Pulmonary Artery Hypertension Model

Resumo Fundamento A hipertrofia e a dilatação do ventrículo direito observadas na hipertensão arterial pulmonar (HAP) prejudicam a dinâmica do ventrículo esquerdo (VE) achatando o septo interventricular. Objetivo Investigar se o treinamento físico resistido (TFR) de intensidade baixa a moderada é benéfico para funções contráteis do VE e de cardiomiócitos em ratos durante o desenvolvimento de HAP induzida por monocrotalina (MCT). Métodos Foram usados ratos Wistar machos (Peso corporal: ~ 200 g). Para avaliar o tempo até o possível surgimento de insuficiência cardíaca (ou seja, ponto de desfecho), os ratos foram divididos em dois grupos, hipertensão com sedentarismo até a insuficiência (HSI, n=6) e hipertensão com treinamento até a insuficiência (HTI, n=6). Para testar os efeitos do TFR, os ratos foram divididos entre grupos de controle sedentários (CS, n=7), hipertensão com sedentarismo (HS, n=7) e hipertensão com treinamento (HT, n=7). A HAP foi induzida por duas injeções de MCT (20 mg/kg, com um intervalo de 7 dias). Os grupos com treinamento foram submetidos a um protocolo de TFR (subir escadas; 55-65% da máxima carga carregada), 5 dias por semana. A significância estatística foi definida em p <0,05. Resultados O TFR prolongou o ponto de desfecho (~25%), melhorou a tolerância ao esforço físico (~55%) e atenuou as disfunções de contratilidade de VE e de cardiomiócitos promovidas pela MCT preservando a fração de ejeção e o encurtamento fracional, a amplitude do encurtamento, e as velocidades de contração e relaxamento nos cardiomiócitos. O TFR também preveniu os aumentos de fibrose e colágeno tipo I no ventrículo esquerdo causados pela MCT, além de manter as dimensões de miócitos e colágeno tipo III reduzidas por MCT. Conclusão O TFR de intensidade baixa a moderada é benéfico para funções contráteis de VE e cardiomiócitos em ratos durante o desenvolvimento de HAP induzida por MCT.

Abstract Background The right ventricular hypertrophy and dilation observed in pulmonary artery hypertension (PAH) damages the left ventricle (LV) dynamics by flattening the interventricular septum. Objective To investigate whether low- to moderate-intensity resistance exercise training (RT) is beneficial to LV and cardiomyocyte contractile functions in rats during the development of monocrotaline (MCT)-induced PAH. Methods Male Wistar rats (Body weight: ~ 200 g) were used. To assess the time to potential heart failure onset (i.e., end point), rats were divided into sedentary hypertension until failure (SHF, n=6) and exercise hypertension until failure (EHF, n=6) groups. To test RT effects, rats were divided into sedentary control (SC, n = 7), sedentary hypertension (SH, n=7), and exercise hypertension (EH, n=7) groups. PAH was induced by two MCT injections (20 mg/kg, with 7 days interval). Exercise groups were submitted to an RT protocol (Ladder climbing; 55-65% of carrying maximal load), 5 times/week. Statistical significance was assumed at P < 0.05. Results RT prolonged the end point (~25 %), enhanced the physical effort tolerance (~ 55%), and mitigated the LV and cardiomyocyte contractility dysfunctions promoted by MCT by preserving the ejection fraction and fractional shortening, the amplitude of shortening, and the velocities of contraction and relaxation in cardiomyocytes. RT also prevented increases in left ventricle fibrosis and type I collagen caused by MCT, and maintained the type III collagen and myocyte dimensions reduced by MCT. Conclusion Low- to moderate-intensity RT benefits LV and cardiomyocyte contractile functions in rats during the development of MCT-induced PAH.

Resistance Exercise Training Mitigates Left Ventricular Dysfunctions in Pulmonary Artery Hypertension Model. / O Treinamento Físico Resistido Atenua as Disfunções Ventriculares Esquerdas em Modelo de Hipertensão Arterial Pulmonar.

BACKGROUND: The right ventricular hypertrophy and dilation observed in pulmonary artery hypertension (PAH) damages the left ventricle (LV) dynamics by flattening the interventricular septum. OBJECTIVE: To investigate whether low- to moderate-intensity resistance exercise training (RT) is beneficial to LV and cardiomyocyte contractile functions in rats during the development of monocrotaline (MCT)-induced PAH. METHODS: Male Wistar rats (Body weight: ~ 200 g) were used. To assess the time to potential heart failure onset (i.e., end point), rats were divided into sedentary hypertension until failure (SHF, n=6) and exercise hypertension until failure (EHF, n=6) groups. To test RT effects, rats were divided into sedentary control (SC, n = 7), sedentary hypertension (SH, n=7), and exercise hypertension (EH, n=7) groups. PAH was induced by two MCT injections (20 mg/kg, with 7 days interval). Exercise groups were submitted to an RT protocol (Ladder climbing; 55-65% of carrying maximal load), 5 times/week. Statistical significance was assumed at P < 0.05. RESULTS: RT prolonged the end point (~25 %), enhanced the physical effort tolerance (~ 55%), and mitigated the LV and cardiomyocyte contractility dysfunctions promoted by MCT by preserving the ejection fraction and fractional shortening, the amplitude of shortening, and the velocities of contraction and relaxation in cardiomyocytes. RT also prevented increases in left ventricle fibrosis and type I collagen caused by MCT, and maintained the type III collagen and myocyte dimensions reduced by MCT. CONCLUSION: Low- to moderate-intensity RT benefits LV and cardiomyocyte contractile functions in rats during the development of MCT-induced PAH.

FUNDAMENTO: A hipertrofia e a dilatação do ventrículo direito observadas na hipertensão arterial pulmonar (HAP) prejudicam a dinâmica do ventrículo esquerdo (VE) achatando o septo interventricular. OBJETIVO: Investigar se o treinamento físico resistido (TFR) de intensidade baixa a moderada é benéfico para funções contráteis do VE e de cardiomiócitos em ratos durante o desenvolvimento de HAP induzida por monocrotalina (MCT). MÉTODOS: Foram usados ratos Wistar machos (Peso corporal: ~ 200 g). Para avaliar o tempo até o possível surgimento de insuficiência cardíaca (ou seja, ponto de desfecho), os ratos foram divididos em dois grupos, hipertensão com sedentarismo até a insuficiência (HSI, n=6) e hipertensão com treinamento até a insuficiência (HTI, n=6). Para testar os efeitos do TFR, os ratos foram divididos entre grupos de controle sedentários (CS, n=7), hipertensão com sedentarismo (HS, n=7) e hipertensão com treinamento (HT, n=7). A HAP foi induzida por duas injeções de MCT (20 mg/kg, com um intervalo de 7 dias). Os grupos com treinamento foram submetidos a um protocolo de TFR (subir escadas; 55-65% da máxima carga carregada), 5 dias por semana. A significância estatística foi definida em p <0,05. RESULTADOS: O TFR prolongou o ponto de desfecho (~25%), melhorou a tolerância ao esforço físico (~55%) e atenuou as disfunções de contratilidade de VE e de cardiomiócitos promovidas pela MCT preservando a fração de ejeção e o encurtamento fracional, a amplitude do encurtamento, e as velocidades de contração e relaxamento nos cardiomiócitos. O TFR também preveniu os aumentos de fibrose e colágeno tipo I no ventrículo esquerdo causados pela MCT, além de manter as dimensões de miócitos e colágeno tipo III reduzidas por MCT. CONCLUSÃO: O TFR de intensidade baixa a moderada é benéfico para funções contráteis de VE e cardiomiócitos em ratos durante o desenvolvimento de HAP induzida por MCT.

Tools for Assessing Knowledge of Back Health in Adolescents: A Systematic Review Protocol.

Back pain is common in adolescents as a result of their typical daily activities. There is a critical need for developing instruments that can assess the adolescents' knowledge of proper posture, because adequate postural habits are essential for preventing back pain and facilitating physical well-being. Unfortunately, there is insufficient understanding about appropriate back health in the general public, even though this knowledge is decisive in the development of physical skills and attainment of health literacy. Furthermore, relevant substantive literature is scarce. Therefore, the proposed systematic review aims to identify instruments that are used for assessing knowledge of back health in adolescents. Relevant search terms and descriptors will be combined, and searches will be carried out in a uniform sequence within the PubMed, Embase, CINAHL, and Cochrane Library databases. Eligible articles must present data on the assessment of the adolescents' knowledge of back health and describe the applied instrumentation. Articles will be selected by two reviewers independently; all disagreements will be resolved by a third reviewer. Mendeley and the Rayyan software will be used for the systematic review, and the checklist proposed by Brink and Louw will be used to verify the methodological quality of the included studies. Our findings may confirm the relevance of constructing and validating back health instruments for use in Brazil and other countries.

Effects of moderate-continuous and high-intensity interval aerobic training on cardiac function of spontaneously hypertensive rats.

The aim of this study was to verify the effects of moderate-intensity continuous (MICT) and high-intensity interval (HIIT) aerobic training on cardiac morphology and function and the mechanical properties of single cardiomyocytes in spontaneously hypertensive rats (SHR) in the compensated phase of hypertension. Sixteen-week-old male SHR and normotensive Wistar (WIS) rats were allocated to six groups of six animals each: SHR CONT or WIS CONT (control); SHR MICT or WIS MICT (underwent MICT, 30 min/day, five days per week for eight weeks); and SHR HIIT or WIS HIIT (underwent HIIT, 30 min/day, five days per week for eight weeks). Total exercise time until fatigue and maximum running speed were determined using a maximal running test before and after the experimental period. Systolic (SAP), diastolic (DAP), and mean (MAP) blood pressures were measured using tail plethysmography before and after the experimental period. Echocardiographic evaluations were performed at the end of the experimental period. The rats were euthanized after in vivo assessments, and left ventricular myocytes were isolated to evaluate global intracellular Ca2+ transient ([Ca2+]i) and contractile function. Cellular measurements were performed at basal temperature (~37°C) at 3, 5, and 7 Hz. The results showed that both training programs increased total exercise time until fatigue and, consequently, maximum running speed. In hypertensive rats, MICT decreased SAP, DAP, MAP, interventricular septal thickness during systole and diastole, and the contraction amplitude at 5 Hz. HIIT increased heart weight and left ventricular wall thickness during systole and diastole and reduced SAP, MAP, and the time to peak [Ca2+]i at all pacing frequencies. In conclusion, both aerobic training protocols promoted beneficial adaptations to cardiac morphology, function, and mechanical properties of single cardiomyocytes in SHR.

Equations based on anthropometric measurements for adipose tissue, body fat, or body density prediction in children and adolescents: a scoping review.

PURPOSE: Assessing the body composition of children and adolescents is important to monitor their health status. Anthropometric measurements are feasible and less-expensive than other techniques for body composition assessment. This study aimed to systematically map anthropometric equations to predict adipose tissue, body fat, or density in children and adolescents, and to analyze methodological aspects of the development of anthropometric equations using skinfolds. METHODS: A scoping review was carried out following the PRISMA-ScR criteria. The search was carried out in eight databases. The methodological structure protocol of this scoping review was retrospectively registered in the Open Science Framework ( https://osf.io/35uhc/ ). RESULTS: We included 78 reports and 593 anthropometric equations. The samples consisted of healthy individuals, people with different diseases or disabilities, and athletes from different sports. Dual-energy X-ray absorptiometry (DXA) was the reference method most commonly used in developing equations. Triceps and subscapular skinfolds were the anthropometric measurements most frequently used as predictors in the equations. Age, stage of sexual maturation, and peak height velocity were used as complementary variables in the equations. CONCLUSION: Our scoping review identified equations proposed for children and adolescents with a great diversity of characteristics. In many of the reports, important methodological aspects were not addressed, a factor that may be associated with equation bias. LEVEL IV: Evidence obtained from multiple time series analysis such as case studies. (NB: dramatic results in uncontrolled trials might also be regarded as this type of evidence).

Is the Wistar Rat a more Suitable Normotensive Control for SHR to Test Blood Pressure and Cardiac Structure and Function?

Abstract Background: There are divergences in the literature regarding the experimental model (Wistar-WIS or Wistar Kyoto-WKY) to be used as a Spontaneously Hypertensive Rat (SHR) control. The characterization of these models in terms of cardiovascular parameters provides researchers with important tools at the time of selection and application in scientific research. Objective: The aim of this study was to evaluate the use of WIS and WKY as a Spontaneously Hypertensive Rat (SHR) control by assessing the long-term behavior of blood pressure and cardiac structure and function in these strains. Methods: To this end, WIS, WKY, and SHR underwent longitudinal experiments. Blood pressure and body mass were measured every two weeks from the 8th to the 72nd. Echocardiographic analysis was performed in all groups with 16, 48, and 72 weeks of life. After having applied the normality test, the Two-Way ANOVA of repeated measures followed by the Tukey post hoc test was used. A significance level of 5% was established. Results: The WIS group showed higher body mass (p<0.05), while the WKY and SHR presented higher body mass variation over time (p<0.05). SHR exhibited increased values of systolic, diastolic, and mean blood pressure when compared to WKY and WIS, whereas the WKY generally showed higher values than WIS (p<0.05). Regarding the cardiac function, SHR showed reduced values, while the WKY presented an early decrease when compared to WIS with aging (p<0.05). Conclusion: WIS is a more suitable normotensive control for SHR than WKY in experiments to test blood pressure and cardiac structure and function.

Anxiety, sleep quality and mood in elite athletes during the COVID-19 pandemic: a preliminary study.

BACKGROUND: The social isolation (quarantine) caused by COVID-19 has generated several consequences for the physical and mental health of the general population; however, little is known about the effects of this disease on elite athletes. We seek to assess the effect of social isolation on anxiety, sleep quality and quality of life for elite athletes. METHODS: 206 athletes from collective and individual sports (116 men and 90 women) participated in the present study, with an average age of 24.61±8.73 years. Time devoted to physical training before and during the pandemic was assessed. Assessment of anxiety symptoms, sleep quality and mood were assessed using semistructured questionnaires. RESULTS: There was a reduction in hours dedicated to training, as well as in training sessions for both groups evaluated. There is a high prevalence (>90%) of anxiety symptoms (medium and high) in both groups. There were no major losses in the sleep quality of the athletes (>75% presented regular to very good sleep). CONCLUSIONS: There are no differences regarding the traits and state of anxiety between athletes of collective and individual modalities. However, both groups showed traces of anxiety, which, from the point of view of health, becomes worrying.

Fatores associados à satisfação e distorção da imagem corporal em crianças de 7 a 10 anos de idade / Factors associated with satisfaction and distortion of body image among children from 7 to 10 years of age

RESUMO O objetivo deste estudo é analisar a satisfação e distorção da imagem corporal em crianças de 7 a 10 anos de idade e verificar quais fatores antropométricos e socioeconômicos estão associados a elas. Trata-se de um estudo transversal, realizado com 307 crianças de escolas públicas de Goiânia. A saúde da criança e os aspectos socioeconômicos da família foram avaliados por meio de um questionário semiestruturado; a imagem corporal foi avaliada por meio da Escala de Silhuetas Brasileiras Para Crianças; e também foram coletados dados antropométricos de peso, estatura, dobras cutâneas e circunferência da cintura. Observou-se homogeneidade do gênero neste estudo, predomínio de meninos (52%) eutróficos (73%). Apesar de se tratar de uma amostra com peso saudável, a insatisfação e a distorção da imagem corporal prevaleceram sobre a maior parte da amostra: a insatisfação esteve presente em 92% das crianças, prevalecendo o desejo por uma menor silhueta, enquanto a distorção esteve presente em 75% da amostra, com predomínio da subestimação da silhueta. No entanto, este estudo encontrou associação da insatisfação com a imagem corporal apenas com IMC (aferido, atual e desejado) e circunferência da cintura; e associação da distorção da imagem corporal apenas com os IMC (aferido e atual).

ABSTRACT The aim of this study is to analyze the satisfaction and distortion of body image in children from 7 to 10 years old and to verify which anthropometric and socioeconomic factors are associated with them. This is a cross-sectional study, carried out with 307 children from public schools in Goiânia. The child's health and the socioeconomic aspects of the family were assessed using a semi-structured questionnaire; body image was assessed using the Brazilian Silhouettes Scale for Children; and anthropometric data on weight, height, skinfolds and waist circumference were also collected. Gender homogeneity was observed in this study, with a predominance of eutrophic(73%) boys (52%). Despite being a sample with a healthy weight, dissatisfaction and distortion of body image prevailed over most of the sample: dissatisfaction was present in 92% of children, the desire for a smaller silhouette prevailing, while distortion was present in 75% of the sample, with a predominance of underestimation of the silhouette. However, this study found dissatisfaction association with body image only with BMI (measured, current and desired) and waist circumference; and association of the distortion of the body image only with the BMI (measured and current).

Core temperature circadian rhythm across aging in Spontaneously Hypertensive Rats.

The purpose of this study was to evaluate the circadian rhythm of core temperature (Tcore) across aging in Spontaneously Hypertensive Rats (SHR) with comparison to the two rat strains often used as their normotensive control animals, namely, Wistar (WIS) and Wistar Kyoto (WKY). METHODS: WIS, WKY and SHR rats were subdivided into three different groups according their age: WIS16, WIS48, WIS72, WKY16, WKY48, WKY72, SHR16, SHR48 and SHR72 weeks-old. Body mass and blood pressure were periodically measured along the experiments. All animal group had their circadian rhythm of Tcore evaluated over three consecutive days (72 h) by telemetry using an implanted temperature sensor. The Tcore circadian rhythm was averaged in 1-h blocks and analyzed using the cosinor method. RESULTS: Sixteen-week-old SHR (SHR16) presented higher Tcore than WIS16 (from 06am to 06pm) and WKY16 (from 07am to 06pm). Both normotensive groups exhibited increases in Tcore during circadian rhythm with aging. The cosinor analysis showed no differences between strains and ages for the acrophase. An age effect on the SHR strain (SHR16 < SHR72) was observed regarding the amplitude. SHR16 had higher values regarding MESOR compared to WIS16 and WKY16. In addition, WIS72 and WKY72 showed higher values than WIS16 and WKY16, respectively. Finally, no differences were observed in the strength rhythm analysis. CONCLUSIONS: SHR presented impaired thermoregulatory control at only 16 weeks of age when showing a higher body temperature during the activity phase, while other circadian rhythm parameters showed no differences across aging. Therefore, in taking our results as a whole we can conclude that WIS and WKY are appropriate Wistar strains to be used as normotensive controls for SHR.

Continuous Aerobic Exercise Prevents Detrimental Remodeling and Right Heart Myocyte Contraction and Calcium Cycling Dysfunction in Pulmonary Artery Hypertension.

ABSTRACT: Pulmonary artery hypertension (PAH) imposes right heart and lung detrimental remodeling which impairs cardiac contractility, physical effort tolerance, and survival. The effects of an early moderate-intensity continuous aerobic exercise training on the right ventricle and lung structure, and on contractility and the calcium (Ca2+) transient in isolated myocytes from rats with severe PAH induced by monocrotaline were analyzed. Rats were divided into control sedentary (CS), control exercise (CE), monocrotaline sedentary (MS), and monocrotaline exercise (ME) groups. Animals from control exercise and ME groups underwent a moderate-intensity aerobic exercise on a treadmill (60 min/d; 60% intensity) for 32 days, after a monocrotaline (60 mg/kg body weight i.p.) or saline injection. The pulmonary artery resistance was higher in MS than in control sedentary (1.36-fold) and was reduced by 39.39% in ME compared with MS. Compared with MS, the ME group presented reduced alveolus (17%) and blood vessel (46%) wall, fibrosis (25.37%) and type I collagen content (55.78%), and increased alveolus (52.96%) and blood vessel (146.97%) lumen. In the right ventricle, the ME group exhibited diminished hypertrophy index (25.53%) and type I collagen content (40.42%) and improved myocyte contraction [ie, reduced times to peak (29.27%) and to 50% relax (13.79%)] and intracellular Ca2+ transient [ie, decreased times to peak (16.06%) and to 50% decay (7.41%)] compared with MS. Thus, early moderate-intensity continuous aerobic exercise prevents detrimental remodeling in the right heart and lung increases in the pulmonary artery resistance and dysfunction in single myocyte contraction and Ca2+ cycling in this model.

Distorção da imagem corporal em bailarinas jovens / Body image distortion in young dancers / Distorción de imagen corporal en balerina joven

O objetivo do estudo foi analisar a imagem corporal de bailari- nas jovens e relacionar com suas medidas antropométricas. Um objetivo secundário foi comparar as medidas antropométricas aferidas e referi- das pelas bailarinas. O estudo teve delineamento transversal com uma amostra de 33 bailarinas entre 13 e 17 anos de idade. Foram coletados dados biossocioeconômicos, e a imagem corporal foi avaliada através do Body Shape Questionnaire (BSQ), para determinar a sua distorção e preo- cupação. Os resultados mostraram que a maioria das bailarinas apre- sentou distorção da imagem corporal, no entanto, houve baixa preva- lência de preocupação com a imagem corporal. Além disso, as bailarinas subestimam seu índice de massa corporal em relação à medida aferida pelos pesquisadores.

The aim of the study was to analyze body image and relate it to anthropometric measurements of young dancers. The secondary objective was to compare the anthropometric measures measured and reported by the dancers. The study had a cross-sectional design with a sample of 33 dancers between 13 and 17 years of age. Socioeconomic data were collected, and body image was assessed using the Body Shape Questionnaire (BSQ) to determine distortion and concern with body image. The results showed that most dancers presented distortion of body image, however there was a low prevalence of concern with body image. In addition, the dancers underestimate their body mass index in relation to the measurement measured by the researchers.

El objetivo del estudio fue analizar la imagen corporal y relacionarla con mediciones antropométricas de jóvenes bailarines. El objetivo secundario fue comparar las medidas antropométricas medidas e informadas por los bailarines. El estudio tuvo un diseño transversal con una muestra de 33 bailarines entre 13 y 17 años. Se recogieron datos biosocioeconómicos y se evaluó la imagen corporal utilizando el cuestionario de forma corporal (BSQ) para determinar la distorsión y la preocupación por la imagen corporal. Los resultados mostraron que la mayoría de los bailarines presentaron distorsión de la imagen corporal, sin embargo, hubo una baja prevalencia de preocupación con la imagen corporal. Además, los bailarines subestiman su índice de masa corporal en relación con la medición medida por los investigadores.

Voluntary running counteracts right ventricular adverse remodeling and myocyte contraction impairment in pulmonary arterial hypertension model.

AIM: Analyze the effects of voluntary running during the development of pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT) on the right ventricle (RV) structure, RV myocyte contractility and intracellular Ca2+ transient in rats with MCT-induced PAH. MAIN METHODS: Male Wistar rats were housed sedentary or with free access to a running wheel after MCT or saline injection for until HF or median end-point day of HF in sedentary animals (24 days). Echocardiographic examination and exercise tolerance test were carried out at specific time points of the experimental period. After euthanasia, the heart was dissected, weighed and processed for either histological or single myocyte contractility and intracellular Ca2+ transient analyzes. KEY FINDINGS: Voluntary running delayed the onset of HF (29 days) and the increase in pulmonary artery resistance, and improved exercise tolerance. In the median end-point day of HF, exercise retarded RV adverse remodeling (i.e. increase in extracellular matrix and collagen content). At this stage, exercise also delayed impairments in cell contractile function (i.e. amplitude and times to peak and to half relaxation) and intracellular calcium cycling (i.e. amplitude and times to peak and to half decay) in RV single myocytes. SIGNIFICANCE: Along with HF onset delay and physical effort tolerance enhancement, voluntary running during the development of PAH postpones pulmonary artery resistance increases, RV adverse remodeling and myocyte contractility and intracellular calcium cycling deterioration in rats. Therefore, self-paced intermittent exercise of high intensity may contribute positively to the health and survival of individuals with PAH.

Thermoregulation in Hypertensive Rats during Exercise: Effects of Physical Training / Termorregulação durante o Exercício em Ratos Hipertensos: Efeitos do Treinamento Físico

Abstract Background: Spontaneously hypertensive rats (SHR) show deficit in thermal balance during physical exercise. Objective: To assess the effects of low-intensity physical exercise training on thermal balance of hypertensive rats undergoing an acute exercise protocol. Methods: Sixteen-week-old male Wistar rats and SHR were allocated into four groups: control Wistar rats (C-WIS), trained Wistar (T-WIS), control SHR (C-SHR) and trained SHR (T-SHR). Treadmill exercise training was performed for 12 weeks. Blood pressure, resting heart rate and total exercise time was measured before and after the physical exercise program. After the exercise program, a temperature sensor was implanted in the abdominal cavity, and the animals subjected to an acute exercise protocol, during which internal body temperature, tail skin temperature and oxygen consumption until fatigue were continuously recorded. Mechanical efficiency (ME), work, heat dissipation threshold and sensitivity were calculated. Statistical significance was set at 5%. Results: Physical training and hypertension had no effect on thermal balance during physical exercise. Compared with C-WIS, the T-WIS group showed higher heat production, which was counterbalanced by higher heat dissipation. Hypertensive rats showed lower ME than normotensive rats, which was not reversed by the physical training. Conclusion: Low-intensity physical training did not affect thermal balance in SHR subjected to acute exercise.

Resumo Fundamento: Ratos espontaneamente hipertensos (SHR) apresentam déficits no balanço térmico durante o exercício físico. Objetivo: Avaliar os efeitos do treinamento físico de baixa intensidade sobre o balanço térmico de ratos hipertensos submetidos a um protocolo de exercício físico agudo. Métodos: Ratos machos Wistar e SHR, com 16 semanas de idade, foram divididos em quatro grupos experimentais: Wistar controle (WIS-C), Wistar treinado (WIS-T), SHR controle (SHR-C) e SHR treinado (SHR-T). O treinamento físico em esteira rolante foi realizado durante 12 semanas. A pressão arterial, a frequência cardíaca de repouso e o tempo de exercício foram medidos previamente e após o programa de treinamento físico. Após o programa de treinamento físico, um sensor de temperatura foi implantado na região intraperitoneal e os ratos foram submetidos a um protocolo de exercício físico agudo com registros contínuos da temperatura corporal interna, temperatura da pele da cauda e do consumo de oxigênio até a fadiga. A eficiência mecânica (EM), o trabalho, o limiar e a sensibilidade para dissipação de calor foram calculados. Para as análises estatísticas o nível de significância adotado foi de 5%. Resultados: O treinamento físico e a hipertensão arterial não alteraram o balanço térmico durante o exercício físico. O grupo WIS-T quando comparado ao WIS-C, apresentou maior produção de calor, que foi contrabalanceado por uma maior dissipação de calor. Os animais hipertensos apresentaram menor EM em comparação aos animais normotensos, e o treinamento físico não foi capaz de reverter esta alteração. Conclusão: O treinamento físico de baixa intensidade não provocou alterações no balanço térmico de ratos hipertensos submetidos a um protocolo de exercício físico agudo.

Thermoregulation in Hypertensive Rats during Exercise: Effects of Physical Training.

BACKGROUND: Spontaneously hypertensive rats (SHR) show deficit in thermal balance during physical exercise. OBJECTIVE: To assess the effects of low-intensity physical exercise training on thermal balance of hypertensive rats undergoing an acute exercise protocol. METHODS: Sixteen-week-old male Wistar rats and SHR were allocated into four groups: control Wistar rats (C-WIS), trained Wistar (T-WIS), control SHR (C-SHR) and trained SHR (T-SHR). Treadmill exercise training was performed for 12 weeks. Blood pressure, resting heart rate and total exercise time was measured before and after the physical exercise program. After the exercise program, a temperature sensor was implanted in the abdominal cavity, and the animals subjected to an acute exercise protocol, during which internal body temperature, tail skin temperature and oxygen consumption until fatigue were continuously recorded. Mechanical efficiency (ME), work, heat dissipation threshold and sensitivity were calculated. Statistical significance was set at 5%. RESULTS: Physical training and hypertension had no effect on thermal balance during physical exercise. Compared with C-WIS, the T-WIS group showed higher heat production, which was counterbalanced by higher heat dissipation. Hypertensive rats showed lower ME than normotensive rats, which was not reversed by the physical training. CONCLUSION: Low-intensity physical training did not affect thermal balance in SHR subjected to acute exercise.

Estresse térmico ambiental e termorregulação em jogadores de futebol: uma revisão sistemática / Environmental thermal stress and thermoregulation in soccer players: a systematic review / Estrés térmico ambiental y termorregulación en jugadores de fútbol: una revisión sistemática

Resumo O objetivo do estudo foi fazer uma revisão sistemática acerca dos efeitos do estresse térmico ambiental sobre a termorregulação em jogadores de futebol. Foram avaliados estudos em bases de dados pertencentes ao portal Periódicos Capes. Foi empregado o método Prisma para o desenvolvimento da revisão. Jogadores de futebol apresentam grande aumento da temperatura corporal associada à redução de desempenho físico durante o jogo em ambiente quente. Em relação às estratégias para amenizar esse prejuízo (ex. resfriamento, hidratação, aclimatação e aquecimento), o pequeno número de trabalhos encontrado (n = 18) apresenta resultados controversos, portanto são necessários mais estudos.

Abstract The objective of the study was to systematically review the effects of the environmental thermal stress on thermoregulation in soccer players. We analyzed studies from databases belonging to the Periódicos Capes portal. The PRISMA method was used to perform the review. Soccer players exhibit high increase in body temperature associated with reduction in physical performance during game in warm environment. Concerning strategies to mitigate such impairment (e.g. cooling, hydration, acclimatization, warm up and heating), the small number of studies analyzed (n = 18) showed controversial results, which warrants more studies.

Resumen El objetivo del estudio fue llevar a cabo una revisión sistemática sobre los efectos del estrés térmico ambiental en la termorregulación de jugadores de fútbol. Se evaluaron estudios en bases de datos pertenecientes al portal Periódicos Capes. Se empleó el método PRISMA para el desarrollo de la revisión. Los jugadores de fútbol presentan un gran aumento de la temperatura corporal asociada con la reducción de rendimiento físico durante el juego en un entorno caluroso. En cuanto a las estrategias para disminuir esta alteración (p. ej., enfriamiento, hidratación, aclimatación y calentamiento), el pequeño número de trabajos encontrados (n= 18) presentan resultados controvertidos, por lo que es necesaria la realización de más estudios.

Physical Exercise and Regulation of Intracellular Calcium in Cardiomyocytes of Hypertensive Rats / Exercício Físico e Regulação de Cálcio Intracelular em Cardiomiócitos de Ratos Hipertensos

Abstract Background: Regulation of intracellular calcium (Ca2+) in cardiomyocytes is altered by hypertension; and aerobic exercise brings benefits to hypertensive individuals. Objective: To verify the effects of aerobic exercise training on contractility and intracellular calcium (Ca2+) transients of cardiomyocytes and on the expression of microRNA 214 (miR-214) in the left ventricle of spontaneously hypertensive rats (SHR). Methods: SHR and normotensive Wistar rats of 16 weeks were divided into 4 groups -sedentary hypertensive (SH); trained hypertensive (TH); sedentary normotensive (SN); and trained normotensive (TN). Animals of the TH and TN groups were subjected to treadmill running program, 5 days/week, 1 hour/day at 60-70% of maximum running velocity for 8 weeks. We adopted a p ≤ 0.05 as significance level for all comparisons. Results: Exercise training reduced systolic arterial pressure in hypertensive rats. In normotensive rats, exercise training reduced the time to 50% cell relaxation and the time to peak contraction and increased the time to 50% decay of the intracellular Ca2+ transients. In SHR, exercise increased the amplitude and reduced the time to 50% decay of Ca2+ transients. Exercise training increased the expression of miR-214 in hypertensive rats only. Conclusion: The aerobic training applied in this study increased the availability of intracellular Ca2+ and accelerated the sequestration of these ions in left ventricular myocytes of hypertensive rats, despite increased expression of miR-214 and maintenance of cell contractility.

Resumo Fundamento: A regulação intracelular de cálcio (Ca2+) em cardiomiócitos é alterada pela hipertensão, e o exercício físico aeróbico traz benefícios para hipertensos. Objetivo: Verificar os efeitos do treinamento físico aeróbico sobre a contratilidade e a concentração intracelular de Ca2+ transitória em miócitos e a expressão do microRNA 214 no ventrículo esquerdo (VE) de ratos espontaneamente hipertensos (SHR). Métodos: SHR e ratos Wistar normotensos com 16 semanas de idade foram divididos em 4 grupos de 13 animais cada: hipertenso sedentário (HS); hipertenso treinado (HT); normotenso sedentário (NS); normotenso treinado (NT). Os animais dos grupos HT e NT foram submetidos a um programa de treinamento progressivo de corrida em esteira, 5 dias/semana, 1 hora/dia, em intensidade de 60-70% da velocidade máxima de corrida, durante 8 semanas. Adotou-se p ≤ 0,05 como nível de significância em todas as comparações. Resultados: O treinamento físico reduziu a pressão arterial sistólica nos animais hipertensos. Nos animais normotensos, o treinamento físico reduziu o tempo para 50% de relaxamento celular e o tempo para o pico de contração celular, mas aumentou o tempo para 50% de decaimento da concentração intracelular de Ca2+ transitória. Nos animais SHR, o treinamento físico aumentou a amplitude e reduziu o tempo para 50% de decaimento da concentração intracelular de Ca2+ transitória, sem alterar a contratilidade celular. O treinamento físico aumentou a expressão do miR-214 apenas nos animais hipertensos. Conclusão: O treinamento aeróbico utilizado aumenta a disponibilidade e acelera o sequestro de Ca2+ intracelular em miócitos do VE de ratos hipertensos, apesar do aumento da expressão de miR-214 e da manutenção da contratilidade celular.