Ladder-based resistance training with the progression of training load altered the tibial nerve ultrastructure and muscle fiber area without altering the morphology of the postsynaptic compartment.

Scientific evidence regarding the effect of different ladder-based resistance training (LRT) protocols on the morphology of the neuromuscular system is scarce. Therefore, the present study aimed to compare the morphological response induced by different LRT protocols in the ultrastructure of the tibial nerve and morphology of the motor endplate and muscle fibers of the soleus and plantaris muscles of young adult Wistar rats. Rats were divided into groups: sedentary control (control, n = 9), a predetermined number of climbs and progressive submaximal intensity (fixed, n = 9), high-intensity and high-volume pyramidal system with a predetermined number of climbs (Pyramid, n = 9) and lrt with a high-intensity pyramidal system to exhaustion (failure, n = 9). myelinated fibers and myelin sheath thickness were statistically larger in pyramid, fixed, and failure. myelinated axons were statistically larger in pyramid than in control. schwann cell nuclei were statistically larger in pyramid, fixed, and failure. microtubules and neurofilaments were greater in pyramid than in control. morphological analysis of the postsynaptic component of the plantar and soleus muscles did not indicate any significant difference. for plantaris, the type i myofibers were statistically larger in the pyramid and fixed compared to control. the pyramid, fixed, and failure groups for type ii myofibers had larger csa than control. for soleus, the type i myofibers were statistically larger in the pyramid than in control. pyramid and fixed had larger csa for type ii myofibers than control and failure. the pyramid and fixed groups showed greater mass progression delta than the failure. We concluded that the LRT protocols with greater volume and progression of accumulated mass elicit more significant changes in the ultrastructure of the tibial nerve and muscle hypertrophy without endplate changes.

Previous short-term use of testosterone propionate enhances muscle hypertrophy in Wistar rats submitted to ladder-based resistance training.

To investigate the effects of the previous administration of testosterone propionate (TP) on the morphology of the gastrocnemius muscle of Wistar rats submitted to ladder-based resistance training (LRT). Twenty-eight rats were divided equally into groups: initial control (CI), 4-week TP (CT4), 4-week TP + LRT (TRT), and placebo + LRT (RT). The rats from the CT4 and TRT groups were treated with TP for four weeks (10 mg/kg/week). TRT and RT trained for ten weeks. The rodents were euthanized at the end of the experiment, and gastrocnemius muscle, prostate, and left and right testicles were collected. There was no statistical difference between the RT and TRT for final volume load. The prostate mass of the TRT and RT groups was statistically heavier than the CT4 group (P < 0.01). The TRT group's prostate/body mass ratio was statistically different from the CT4 group (P < 0.05). The TRT group was shown to have larger type I, type II, and mean fCSA fibers than all other groups (P < 0.001). Regarding the nuclei/fiber ratio (N/f), the CT4, RT, and TRT groups had higher values than CI (P < 0.01). In addition, the RT group showed a higher N/f ratio than CT4 (P < 0.001) but lower than TRT (P < 0.001). In conclusion, short-term TP administration before resistance training can elicit a greater N/f ratio and size of the mean fCSA of the Gastrocnemius muscle of young adult Wistar rats than resistance training alone.

Muscle hypertrophy is correlated with load progression delta, climb volume, and total load volume in rodents undergoing different ladder-based resistance training protocols.

We compared the effects of two ladder-based resistance training (LRT) protocols on the skeletal muscle morphology (biceps brachialis and plantaris) of Wistar rats. Also, we correlated the training parameters with the muscle fiber cross-sectional area (fCSA). After maximum load tests (ML), twenty-nine young adult Wistar rats were divided into: CONTROL (n = 9), LIMITED (n = 10, 6-8 climb [2 × 50 %ML, 2 × 75 %ML, 2 × 100 %ML, and 2 × 100 %ML+30 g]) and UNLIMITED (n = 10, ≥4 climbs [50 %ML, 75 %ML, 90 %ML, 100 %ML + 30 g until failure) LRT. After eight weeks, the main results were: 1) For biceps brachialis, the type I, IIa, and mean fCSA was statistically larger in the LIMITED than CONTROL. The nuclei/fiber ratio was statistically higher in the LIMITED and UNLIMITED. The correlations found between total load, absolute delta load, and relative load and fCSA were moderate. 2) For plantaris, the type I, IIa, IIx/b, and mean fCSA was statistically larger in the LIMITED than CONTROL. The type IIa, IIx/b, and mean fCSA was statistically larger in the UNLIMITED than CONTROL. The nuclei/fiber ratio was statistically higher in both trained groups than CONTROL. The correlation between the climbing number, total load, and the fCSA was moderate. The correlation between delta absolute load and fCSA was strong. We concluded that rodents submitted to high-intensity, high-volume LRT, but limited climbing volume per session, presented more significant type I, IIa, IIx/b, and mean fCSA, higher nuclei/fiber ratio, and greater maximum carrying capacity. Also, muscle hypertrophy correlated positively with the load progression, training volume, and total load.

The sciatic and radial nerves seem to adapt similarly to different ladder-based resistance training protocols.

The present study aimed to compare the morphological response induced by different ladder-based resistance training (LRT) protocols on the peripheral nerve ultrastructure of young adult Wistar rats. Twenty-nine rodents were distributed into groups: control (CON), submaximal (SUBMAX [6 climbs/session, moderate intensity, 3x/week]) and maximum (MAX [> 4 climbs/session, maximum intensity, 3x/week]) LRT. After 8 weeks, the radial and sciatic nerves were removed and prepared for transmission electron microscopy. In the radial nerve, the myelinated fibers and axons, myelin sheath thickness, and unmyelinated axons were statistically greater in the SUBMAX and MAX. The MAX group had greater unmyelinated fibers than SUBMAX. The Schwann cell (SC) nuclei diameter was statistically larger in the SUBMAX than the CON. The number of microtubules and neurofilaments was statistically higher in the SUBMAX and MAX. In the sciatic nerve, the myelinated fibers, myelinated and unmyelinated axons, and myelin sheath thickness were statistically greater in the SUBMAX and MAX. The SUBMAX and MAX had more SC at the nuclei level than CON. The SC nuclei were statistically larger in the SUBMAX and MAX. The number of microtubules and neurofilaments was statistically higher in the SUBMAX and MAX. Total training load and total load per climb were not different between groups. The SUBMAX and MAX statistically increased maximum carried load (ML). In conclusion, the different LRT protocols induced similar morphological responses in radial and sciatic nerves, probably due to load progression and equal total load volume.

Ladder-based resistance training elicited similar ultrastructural adjustments in forelimb and hindlimb peripheral nerves of young adult Wistar rats.

To analyze the morphological response induced by high-volume, high-intensity ladder-based resistance training (LRT) on the ultrastructure of the radial (forelimb) and sciatic (hindlimb) nerves of adults Wistar rats. Twenty rats were equally distributed into groups: sedentary (SED) and LRT. After the rodents were subjected to the maximum load (ML) carrying test, the LRT group performed 6-8 progressive climbs (2 × 50% ML, 2 × 75% ML, 2 × 100% ML, and 2 × 100% ML + 30 g) three times per week. After 8 weeks, the radial and sciatic nerves were removed and prepared for transmission electron microscopy. In the radial nerve, myelinated axons cross-sectional area (CSA), unmyelinated axons CSA, myelin sheath thickness, and Schwann cells nuclei area were statistically larger in the LRT group than SED (p < 0.05). Also, the number of microtubules and neurofilaments per field were statistically higher in the LRT group than in SED (p < 0.01). For sciatic nerve, myelinated fibers CSA, unmyelinated axons CSA, myelin sheath thickness, Schwann cells nuclei area, and the number of neurofilaments per field were statistically larger in the LRT group compared to the SED group (p < 0.05). LRT with high-volume and high-intensity effectively induce similar changes in adult Wistar rats' radial and sciatic nerves' ultrastructure.

Remodeling of the skeletal muscle and postsynaptic component after short-term joint immobilization and aquatic training.

Joint immobilization is commonly used as a conservative treatment for osteoarticular and musculotendinous traumas. However, joint immobilization might elicit degenerative effects on the neuromuscular system and muscle atrophy. For this reason, the choice of strategies that mitigate these effects is essential in the post-immobilization period. Therefore, this study aimed to investigate the impact of aquatic training on the morphology of muscle fibers and motor endplates of the gastrocnemius muscle in the post-immobilization period. Male Wistar rats (90 days old) were divided into groups: Sedentary: no procedure; Immobilization: joint immobilization protocol (10 days); Immobilization/non-training: joint immobilization protocol (10 days) followed by four weeks without exercise intervention; Immobilization/training: joint immobilization protocol (10 days) and post-immobilization aquatic training (4 weeks). After the procedures, we quantified the cross-sectional area (CSA), volume and numerical density of different myofibers types, and total and stained area and perimeter of the motor endplate. We demonstrate the following main results: (a) short-term joint immobilization resulted in myofibers atrophy; however, we verified a small change in the postsynaptic component; (b) the period of inactivity after immobilization caused severe changes in the motor endplate (lower stained area, stained perimeter, total area, and total perimeter) and maintenance of muscle atrophy due to immobilization; (c) the prescription of post-immobilization exercise proved to be effective in restoring muscle morphology and inducing plasticity in the motor endplate. We conclude that short-term joint immobilization (10 days) results in atrophy type I and II myofibers, in addition to a decline in the total perimeter of the motor endplate. Besides, the post-immobilization period appears to be decisive in muscle and postsynaptic remodeling. Thus, aquatic training is effective in stimulating adjustments associated with muscle hypertrophy and plasticity of the motor endplate during the post-immobilization period.

Gluteus Maximus Activation during Common Strength and Hypertrophy Exercises: A Systematic Review.

The gluteus maximus (GMax) is one of the primary hip extensors. Several exercises have been performed by strength and conditioning practitioners aiming to increase GMax strength and size. This systematic review aimed to describe the GMax activation levels during strength exercises that incorporate hip extension and use of external load. A search of the current literature was performed using PubMed/Medline, SportDiscuss, Scopus, Google Scholar, and Science Direct electronic databases. Sixteen articles met the inclusion criteria and reported muscle activation levels as a percentage of a maximal voluntary isometric contraction (MVIC). The exercises classified as very high level of GMax activation (>60% MVIC) were step-up, lateral step-up, diagonal step-up, cross over step-up, hex bar deadlift, rotational barbell hip thrust, traditional barbell hip thrust, American barbell hip thrust, belt squat, split squat, in-line lunge, traditional lunge, pull barbell hip thrust, modified single-leg squat, conventional deadlift, and band hip thrust. We concluded that several exercises could induce very high levels of GMax activation. The step-up exercise and its variations present the highest levels of GMax activation followed by several loaded exercises and its variations, such as deadlifts, hip thrusts, lunges, and squats. The results of this systematic review may assist practitioners in selecting exercised for strengthening GMax.

Chronic responses of physical and imagery training on parkinson's disease / Respostas crônicas do treinamento físico e de imagética na doença de parkinson / Respuestas crónicas del entrenamiento físico y de imagética en la enfermedad de parkinson

ABSTRACT Introduction Physical and motor imagery training is known to induce positive results in the quality of life of patients with neurodegenerative diseases. However, it is not known which effects are achievable when both types of training are combined. Objective This study aimed to investigate the effects of a combination of physical and imagery training on neurotrophin levels, the perception of body dimensions and activities of daily living (ADL) in individuals with Parkinson's disease (PD). Methods Over an 8-week period, thirteen subjects underwent one hour of aerobic training in combination with twice-weekly imagery training (MIT). The following parameters were measured: brain-derived neurotrophic factor (BDNF) serum levels, level of dependence for activities of daily living (ADLs - Basic [ABDL] and Instrumental [AIDL]), perception of body dimensions and hand laterality test. Results Physical training combined with MIT increased serum BDNF levels in a non-statistically significant manner by 128.08% (88.81 ± 111.83 pg/ml versus 202.56 ± 183.43 pg/ml, p= 0.068). Delta BDNF showed a mean variation of 218.05 ± 547.55% (ES = 1.04). Perception of body dimensions and hand recognition reaction time both improved, but not in a non-statistically significant manner. ADLs (9.52% in ABDLs and 17.76% in AIDLs) improved in a statistically significant manner. Conclusion Despite the small number of subjects, study limitations, and the fact that most results were non-statistically significant, the results obtained here indicate clinical improvement associated with the neurotrophic action of BDNF on the perception of body dimensions and the functional capacity of Parkinson's disease subjects. Level of evidence II, Therapeutic studies-Investigation of treatment results.

RESUMO Introdução Sabe-se que o treinamento físico e de imagética motora induz a resultados positivos na qualidade de vida dos pacientes com doenças neurodegenerativas. Entretanto, não se sabe quais efeitos são possíveis de se obter quando ambos tipos de treinamento são combinados. Objetivo O presente estudo teve como objetivo investigar os efeitos de uma combinação de treinamento físico e de imagética sobre os níveis neurotróficos, percepção das dimensões corporais e atividades da vida diária (AVD) em indivíduos com doença de Parkinson (DP). Métodos Durante um período de oito semanas, 13 indivíduos realizaram uma hora de treinamento aeróbico em combinação com um treinamento de imagética motora (MIT) duas vezes por semana. Foram mensurados os seguintes parâmetros: níveis séricos do fator neurotrófico derivado do cérebro (BDNF), nível de dependência para atividades de vida diária (AVD - Básico [ABDL] e instrumental [AIDL]), percepção das dimensões corporais e teste de lateralidade da mão. Resultados O treinamento físico combinado ao MIT aumentou os níveis séricos de BDNF de um modo não estatisticamente significativo em 128,08% (88,81 ± 111,83 pg/ml versus 202,56 ± 183,43 pg/ml, p = 0,068). O delta BDNF apresentou uma variação média de 218,05 ± 547,55% (ES = 1,04). A percepção das dimensões corporais e o tempo de reação para o reconhecimento da mão melhoraram, porém, não de um modo significativo estatisticamente. As AVDs (9,52% nas ABDL's e 17,76% nas AIDLs) melhoraram de um modo significativo estatisticamente. Conclusão Apesar do pequeno número de indivíduos, limitações do estudo e ao fato de que a maioria dos resultados não era estatisticamente significativo, os resultados aqui obtidos indicam uma melhora clínica associada à ação neurotrófica do BDNF na percepção das dimensões corporais e na capacidade funcional de indivíduos com doença de Parkinson. Nível de evidência II, Estudos terapêuticos-Investigação dos resultados do tratamento.

RESUMEN Introducción Se sabe que el entrenamiento físico y de imagética motora induce a resultados positivos en la calidad de vida de los pacientes con enfermedades neurodegenerativas. Entretanto, no se sabe qué efectos son posibles de obtenerse cuando ambos tipos de entrenamiento son combinados. Objetivo El presente estudio tuvo como objetivo investigar los efectos de una combinación de entrenamiento físico y de imagética sobre los niveles neurotróficos, la percepción de las dimensiones corporales y las actividades de la vida diaria (AVD) en individuos con enfermedad de Parkinson (EP). Métodos Durante un período de ocho semanas, 13 individuos realizaron una hora de entrenamiento aeróbico en combinación con un entrenamiento de imagética motora (MIT) dos veces por semana. Se midieron los siguientes parámetros: niveles séricos del factor neurotrófico derivado del cerebro (BDNF), nivel de dependencia para las actividades de la vida diaria (AVD - Básico [ABDL] e Instrumental [AIDL]), percepción de las dimensiones corporales y test de lateralidad de la mano. Resultados El entrenamiento físico combinado al MIT aumentó los niveles séricos de BDNF de un modo no estadísticamente significativo en 128,08% (88,81 ± 111,83 pg/ml versus 202,56 ± 183,43 pg/ml, p = 0,068). El delta BDNF mostró una variación promedio de 218,05 ± 547,55% (ES = 1,04). La percepción de las dimensiones corporales y el tiempo de reacción para el reconocimiento de la mano mejoraron, aunque no de un modo estadísticamente significativo. Las AVD (9,52% en las ABDL y 17,76% en AIDL) mejoraron de un modo estadísticamente significativo. Conclusión A pesar del pequeño número de sujetos, limitaciones del estudio y el hecho de que la mayoría de los resultados no era estadísticamente significativos, los resultados obtenidos aquí indican una mejora clínica asociada a la acción neurotrófica del BDNF en la percepción de las dimensiones corporales y la capacidad funcional de individuos con enfermedad de Parkinson. Nivel de evidencia II, Estudios terapéuticos-Investigación de los resultados del tratamiento.

Barbell Hip Thrust, Muscular Activation and Performance: A Systematic Review.

The present systematic review aimed to analyze the activation of the muscles involved in the barbell hip thrust (BHT) and its transfer to sports activities that include horizontal displacement. A search of the current literature was performed using the PubMed, SPORTDiscuss, Scopus and Google Scholar databases. The inclusion criteria were: (a) descriptive studies, (b) physically trained participants, (c) analyzed muscle activation using normalized EMG signals or as a percentage of maximal voluntary isometric contraction (MVIC) and (d) acute or chronic transfer of the BHT to horizontal displacement activity. Twelve articles met the inclusion criteria and the following results were found: 1) neuromuscular activation: hip extensor muscles (gluteus maximus and biceps femoris) demonstrated greater activation in the BHT compared to the squat. The straight bar deadlift exercise demonstrated greater biceps femoris activation than BHT; 2) Regardless of the BHT variation and intensity used, the muscle excitation sequence is gluteus maximus, erector spinae, biceps femoris, semitendinosus, vastus lateralis, gluteus medius, vastus medialis and rectus femoris; 3) acute transfer: four studies demonstrated a significant improvement in sprinting activities after BHT exercise; 4) as for the chronic transfer: two studies demonstrated improvement of the sprint time, while other two studies failed to present such effect. We concluded that: a) the mechanics of BHT favors greater activation of the hip extensor muscles compared to more conventional exercises; b) regardless of the variation of BHT used, the muscle excitation sequence is gluteus maximus, erector spinae, hamstrings, and quadriceps femoris; c) the acute transfer of the post-activation potentiation of the BHT is significant, improving the sprinting time; and d) despite training with BHT submaximal loads can improve sprint times, further investigations are needed.

O tempo de atividade física, a percepção da dimensão e imagem corporal é alterado após a menarca de meninas de alto nível sócio econômico? / Does physical activity time, the perception of body -dimension and -image altered after menarche of girls by high socioeconomic status?

Introdução: A menarca é um marco decisivo sobretudo por provocar inúmeras alterações biológicas. Objetivo: verificar a influencia da menarca na percepção da dimensão e da imagem corporal. Métodos: trinta e oito meninas analisadas antes e a após a menarca. Foram utilizados como parâmetros de avaliação parâmetros antropométricos e as percepções da dimensão e imagem corporal. Resultados: diferenças significativas (p<0,05) foram encontradas nos parâmetros antropométricos e no tempo semanal de atividade física. Considerando a percepção de dimensão corporal diferenças significativas (p<0,05) foram encontradas somente na altura e quadril. Após a menarca diferenças significativas foi encontrada na silhueta real após a menarca. Conclusão: após a menarca as meninas apresentaram alterações antropométricas, redução do tempo de atividade física semanal e modificações na percepção da altura e quadril, bem como da silhueta real.

Introduction: Menarche is a decisive milestone especially for causing numerous biological changes. Objective: evaluated the influence of menarche on perception of dimension and body image. Methods: After confirmation of parental consent thirty-eight girls participate voluntarily in this study. The biometrics and perceptions of body size and image parameters were analyzed before and after menarche period. Results: significant differences (p <0.05) were found in the anthropometric parameters and in the weekly time of physical activity. Considering the perception of body size significant differences (p <0.05) were found only at height and hip. After menarche significant differences were found in the actual silhouette after menarche. Conclusion: in this study, the girls after the menarche presented alterations on anthropometric parameters, on height and waist perception with reduction of the time of weekly physical activity.

[Body image of healthy adolescent women and its association with physical activity: a systematic review]. / Imagem corporal de adolescentes do sexo feminino saudáveis e sua associação com a atividade física: revisão sistemática.

The aim of this study was to evaluate the related scientific production on body image in healthy female adolescents and its association with physical activity. A systematic review of national and international journals was conducted using the major electronic databases. The following inclusion criteria selection were used: sample of female adolescents, with different results; papers in English, Spanish and Portuguese; papers published from 2005 to 2015. Eighteen studies were included and carefully analyzed. The most published paper concentrations were found in Europe (61.2 %). Several studies (95%) used questionnaires as a research instrument to assess physical activity and 55% studies used scales to analyze the body image. No increase was found in the production of literature involving body image study and physical active behavior in healthy female adolescents. In conclusion, the main findings of this review relate to the lack of parameters for the measurement of physical activity and body image analysis. Thus, although it is a current thematic area in the literature, it is possible to consider that the diversity of methodological design between studies makes it difficult to compare the data, making it imperative to standardize instruments and definitions.

O objetivo do trabalho foi analisar a produção cientifica relacionada à imagem corporal em adolescentes do sexo feminino saudáveis e sua associação com a atividade física. Foi realizada uma revisão sistemática da literatura de artigos publicados em periódicos nacionais e internacionais. Os seguintes critérios de inclusão para os artigos foram adotados: amostra composta por adolescentes do sexo feminino e artigos publicados no período de 2005 a 2015. Foram incluídos 18 estudos com uma disparidade regional nas publicações de estudos na Europa (61,2%). A maioria dos estudos (95%) utilizou questionários como instrumentos de pesquisa para a atividade física e 55% utilizou escalas para analisar a imagem corporal, cujos conteúdos variaram, assim como as definições operacionais de atividade física e imagem corporal, dificultando a comparação dos resultados. Não observamos aumento na produção da literatura. Concluindo, os principais achados da presente revisão referem-se à falta de padrão na mensuração da atividade física e na análise da imagem corporal. Dessa forma, embora seja uma temática presente na literatura, é possível considerar que a diversidade de delineamento metodológico entre os estudos dificulta a comparação entre os dados, tornado imperativa a padronização de instrumentos e definições essenciais.

Does resistance training improve body image satisfaction among the elderly? A cross-sectional study.

OBJECTIVE: This study aims to evaluate whether body image satisfaction improves with practice in resistance training in elderly women. METHODS: Forty women were selected and randomly divided into an untrained group (UN) group and a group trained in resistance exercises (RT). To evaluate body image satisfaction, the silhouette matching task was used. RESULTS: No differences were found between current (5.45±0.24) and ideal (4.7±0.12) silhouettes in the RT group. However, the UN group showed a significant difference (p<0.01) between current (10.4±0.43) and ideal (5.6±0.26) silhouettes. The current silhouette was significantly different between the UN and RT groups (p<0.002). However, the ideal silhouette value did not differ between them. Body satisfaction was present in 90% of the participants in the RT group, and the difference was 15% less than that in the UN group (x2 test, p<0.001). CONCLUSION: Resistance training in elderly women can promote satisfaction with their body image.

Positive changes in femoral nerve morphometry in older rats following aerobic training.

The objective of the present study was to analyze alterations of the femoral nerve of aged rats subjected to aerobic training. Wistar rats (12-mo of age) were divided in to two groups: S group (sedentary) and T group (trained). The exercise protocol were 16 weeks long. The groups were sacrificed at 16 months. Ultrafine sections of the femoral nerve have been used. There was no change in the body weight between the groups. T group showed a significant increase in myelinated fiber area, axon diameter, myelin sheath thickness and myelin fiber number compared with sedentary controls. In exercised trained animals, histograms of the frequency distribution of myelinated axons according to their areas showed increased number of medium and large fibers in relation to small fibers, which decreased in number. Aerobic training animals, showed the distribution of myelinated fiber population according to their area being bimodal, with the distribution shifted to the right, indicating increased fiber area. The T group showed a percent damage of large myelinated fibers significantly lower compared to controls. No significant difference was observed between the groups for the g-ratio. The T group also showed a significant increase in the number of microtubules and neurofilaments in myelinated fibers, which was not observed in S group. In conclusion, aerobic training improves nerve structure without evidence of nerve damage and produces an attenuation on the modifications in femoral nerve that develop in old age.

Effects of resistance training on liver structure and function of aged rats.

The aging process may cause negative physiological changes. However, exercises as resistance training (RT) have been considered an important intervention to attenuate these changes. Additionally, liver plays an important role in blood glucose homeostasis in exercise. AIM: This study aimed to analyze the effects of RT on the liver components of aged animals. METHODS: Male Wistar rats were divided into two groups: 24 months' group (CONTROL); and group submitted to a progressive RT protocol for 16 weeks (EXERCISE). Both groups were sacrificed at 24 months. RESULTS: We observed a decrease in blood flow due to the practice of resistance exercises. Besides, our results showed that hepatic tissue plays an important role in glycemic homeostasis during RT. In addition, RT increased mitogen capacity of hepatocytes. CONCLUSIONS: Our study showed many implications for the knowledge about the effects of strength training on old animals' liver.

Imagem corporal de adolescentes do sexo feminino saudáveis e sua associação com a atividade física: revisão sistemática / Body image of healthy adolescent women and its association with physical activity: a systematic review

Resumo O objetivo do trabalho foi analisar a produção cientifica relacionada à imagem corporal em adolescentes do sexo feminino saudáveis e sua associação com a atividade física. Foi realizada uma revisão sistemática da literatura de artigos publicados em periódicos nacionais e internacionais. Os seguintes critérios de inclusão para os artigos foram adotados: amostra composta por adolescentes do sexo feminino e artigos publicados no período de 2005 a 2015. Foram incluídos 18 estudos com uma disparidade regional nas publicações de estudos na Europa (61,2%). A maioria dos estudos (95%) utilizou questionários como instrumentos de pesquisa para a atividade física e 55% utilizou escalas para analisar a imagem corporal, cujos conteúdos variaram, assim como as definições operacionais de atividade física e imagem corporal, dificultando a comparação dos resultados. Não observamos aumento na produção da literatura. Concluindo, os principais achados da presente revisão referem-se à falta de padrão na mensuração da atividade física e na análise da imagem corporal. Dessa forma, embora seja uma temática presente na literatura, é possível considerar que a diversidade de delineamento metodológico entre os estudos dificulta a comparação entre os dados, tornado imperativa a padronização de instrumentos e definições essenciais.

Abstract The aim of this study was to evaluate the related scientific production on body image in healthy female adolescents and its association with physical activity. A systematic review of national and international journals was conducted using the major electronic databases. The following inclusion criteria selection were used: sample of female adolescents, with different results; papers in English, Spanish and Portuguese; papers published from 2005 to 2015. Eighteen studies were included and carefully analyzed. The most published paper concentrations were found in Europe (61.2 %). Several studies (95%) used questionnaires as a research instrument to assess physical activity and 55% studies used scales to analyze the body image. No increase was found in the production of literature involving body image study and physical active behavior in healthy female adolescents. In conclusion, the main findings of this review relate to the lack of parameters for the measurement of physical activity and body image analysis. Thus, although it is a current thematic area in the literature, it is possible to consider that the diversity of methodological design between studies makes it difficult to compare the data, making it imperative to standardize instruments and definitions.

Does resistance training improve body image satisfaction among the elderly? A cross-sectional study

OBJECTIVE: This study aims to evaluate whether body image satisfaction improves with practice in resistance training in elderly women. METHODS: Forty women were selected and randomly divided into an untrained group (UN) group and a group trained in resistance exercises (RT). To evaluate body image satisfaction, the silhouette matching task was used. RESULTS: No differences were found between current (5.45±0.24) and ideal (4.7±0.12) silhouettes in the RT group. However, the UN group showed a significant difference (p<0.01) between current (10.4±0.43) and ideal (5.6±0.26) silhouettes. The current silhouette was significantly different between the UN and RT groups (p<0.002). However, the ideal silhouette value did not differ between them. Body satisfaction was present in 90% of the participants in the RT group, and the difference was 15% less than that in the UN group (x2 test, p<0.001). CONCLUSION: Resistance training in elderly women can promote satisfaction with their body image.

Divergent effects of resistance training and anabolic steroid on the postsynaptic region of different skeletal muscles of aged rats.

This study aimed to analyze the effects of resistance training associated with testosterone administration in the neuromuscular junction (NMJ) postsynaptic region of different skeletal muscle types of aged rats. Wistar rats were divided into: SEI - 20-months-old control, SEF - 24-months-old control, T - 20-months-old with testosterone, S - 20-months-old resistance trained and ST - 20-months-old with resistance training associated with testosterone propionate. All groups were submitted to familiarization and maximum load carrying testing (MLCT). The MLCT was applied before and after the resistance training (RT) period. RT (6-8×/session with progressive loads of 50 to 100%, 3×/week and 120s interval) was performed in ladder climbing for 15weeks. The administration of testosterone propionate was performed 2×/week (10mg/kg/body weight). After euthanize, soleus and plantaris muscles were removed and prepared for histochemistry and cytofluorescence. T, S and ST significantly increased their maximum carrying load capacity compared to SEI and SEF (p<0.05). For soleus postsynaptic region, ST had lower total and stained area than SEF (p<0.05). For plantaris, the postsynaptic component of T was statistically larger than SEI (p<0.05). For soleus histochemistry, T, S and ST groups showed the same magnitude of type I myofibers hypertrophy, thus statistically different from SEI and SEF (p<0.05). The cross-sectional area of the type IIa myofibers of the ST was larger than SEF (p<0.05). The volume density of type I myofibers show to be lower in ST than SEI (p<0.05). As for type IIa myofibers, ST increased Vv [type IIa] compared to SEI and SEF (p<0.05). For plantaris, T significantly hypertrophied type I myofibers compared to SEI and SEF (p<0.05). S and ST demonstrated significant increases of type I myofibers compared to SEI and SEF (p<0.05). As for type IIx myofibers, both S and ST showed myofibers larger than SEI (p<0.05). However, only the ST had significant difference compared to SEF (p<0.05). In conclusion, both therapies, alone or combined, have little effect on the morphology of the NMJ postsynaptic region of distinct muscles. Moreover, the three therapies are potentially stimulating for strength gains and muscle hypertrophy.

Imagem corporal da mulher praticante de exercício físico / Bod image of women practicing exercise

Este estudo teve como objetivo analisar a Imagem Corporal (IC) de mulheres inativas (IN) e praticantes de exercícios físicos: Body Combat (BC) e Yoga (Y). Foram selecionadas 24 mulheres de 18 a 45 anos, praticantes de Yoga (n=8), praticantes de Body Combat (n=8) e Inativas (n=8), que foram avaliadas por meio de uma Escala de Silhuetas. Observamos que a média da silhueta atual, para todos os indivíduos foi sempre superior à média da silhueta ideal, demonstrando insatisfação corporal. A análise estatística apontou diferenças entre as mulheres que praticam Yoga e as Inativas (p<0,01) e houve diferenças entre a silhueta atual e ideal do grupo Inativo (p<0,05). Nesse estudo observou-se que o exercício físico interferiu positivamente no grau de satisfação corporal, evidenciando que os profissionais de Educação Física devem estar atentos e preparados para planejar atividades e programas de exercício que atendam os indivíduos em suas mais diversas necessidades.

Effects of testosterone administration on liver structure and function in aging rats.

Aging males have a decrease in testosterone levels, by which the testosterone treatment may influence in a negatively fashion the liver. AIM: This study aimed to analyze the effects of aging with or without testosterone administration on the liver components of animals. METHODS: Wistar rats were divided into three groups: 20 months' group (G20), 24 months' group (G24), group treated with testosterone for 16 weeks (GT). All groups were sacrificed at 24 months except for G20 that was sacrificed at 20 months. RESULTS: Aging and testosterone treatment alters the body weight (BW), liver weight (LW) and relative liver weight. Besides, testosterone increased the mitogen capacity of hepatocytes. Nonetheless, we reinforce the negative effects of testosterone on old animals' liver as chronic hepatic congestion and/or cholestasis. In addition, we observed that testosterone plays an important role on hepatic glycogen stores. CONCLUSIONS: Our study showed many implications for the knowledge about the effects of aging with or without testosterone administration on old animals' liver.

STRENGTH TRAINING AND ANABOLIC STEROID DO NOT AFFECT MUSCLE CAPILLARIZATION OF MIDDLE-AGED RATS / TREINAMENTO DE FORÇA E ESTEROIDE ANABOLIZANTE NÃO AFETAM A CAPILARIZAÇÃO MUSCULAR DE RATOS DE MEIA-IDADE / ENTRENAMIENTO DE FUERZA Y ESTEROIDE ANABOLIZANTE NO AFECTAN LA CAPILARIDAD MUSCULAR DE RATAS DE MEDIANA EDAD

ABSTRACT Introduction: It is generally accepted that the capillary network decreases with advancing age. The combined effect of resistance training (RT) and testosterone still needs to be elucidated. Objective: This study aimed to measure capillary profile of different skeletal muscles of middle-aged rats undergoing RT and administration of exogenous testosterone. Methods: Wistar rats were divided into five experimental groups: control with 13-month-old rats (SC), control with 16-month-old rats (SE), aged rats + anabolic agent (SA), aged rats + RT (T), and aged rats + RT + anabolic agent (TA). Results: For soleus, the SE group presented a decrease in the percentage of capillaries in comparison to SC group. SA, T, and TA groups had increased capillary volume in comparison to SC. As for the extensor digitorum longus (EDL), SA, T, and TA groups demonstrated lower capillary volume and numeric density in comparison to SC and SE. The EDL of the T and TA groups presented 70% less capillaries than soleus. The numerical and volumetric density and capillary ratio by muscle fiber were not statistically altered by any intervention. The cross-sectional area (CSA) of the soleus of the SA, T and TA groups was statistically different from SC group. The soleus CSA was greater in the TA and T groups than in the SC, SE and SA groups, and the EDL CSA was greater in the TA compared to all other groups. The TA group had greater values than the SE, SA, and T groups. Conclusion: The type of intervention used did not affect any variables measured in the capillary profile. However, the use of anabolic steroid and/or RT showed a tendency to decrease the density of capillaries in the EDL.

RESUMO Introdução: Em geral, se aceita que a rede capilar diminui com o avanço da idade. O efeito combinado de treinamento resistido (TR) e testosterona ainda precisa ser elucidado. Objetivo: Este estudo visou medir o perfil capilar de diferentes músculos esqueléticos em ratos de meia-idade submetidos a TR e administração de testosterona exógena. Métodos: Ratos Wistar foram divididos em cinco grupos experimentais: controle com ratos de 13 meses de idade (SC), controle com ratos de 16 meses de idade (SE), ratos idosos + anabolizante (SA), ratos idosos + TR (T) e ratos idosos + TR + anabolizante (TA) . Resultados: Para o músculo sóleo, o grupo SE apresentou decréscimo do percentual de capilares em comparação com o grupo SC. Os grupos SA, T e TA tiveram aumento do volume de capilares em comparação com o SC. Por outro lado, para o músculo extensor longo dos dedos (ELD), os grupos SA, T e TA demonstraram menor volume e densidade numérica de capilares, em comparação com SC e SE. O músculo ELD dos grupos T e TA apresentou 70% menos capilares do que o sóleo. A densidade numérica e volumétrica e a razão de capilares por fibra muscular não foram estatisticamente alteradas por nenhuma das intervenções. A área de corte transversal (ACT) do músculo sóleo dos grupos SA, T e TA foi estatisticamente diferente do grupo SC. A ACT do sóleo foi maior nos grupos TA e T do que nos grupos SC, SE e SA e a ACT do ELD foi maior no grupo TA comparada com todos os outros grupos. O grupo TA teve valores maiores do que os grupos SE, SA e T. Conclusão: O tipo de intervenção usada não afetou qualquer variável mensurada do perfil capilar. Entretanto, o uso de esteroide anabolizante e/ou TR mostrou tendência de diminuir a densidade de capilares no músculo ELD.

RESUMEN Introducción: Se acepta en general que la red capilar disminuye con la edad. El efecto combinado de entrenamiento de resistencia (ER) y la testosterona todavía necesita ser aclarado. Objetivo: Este estudio tuvo como objetivo medir el perfil capilar de diferentes músculos esqueléticos de ratas de mediana edad sometidas a ER y la administración de testosterona exógena. Métodos: Se dividieron ratas Wistar en cinco grupos: control con ratas de 13 meses de edad (SC), control con ratas de 16 meses de edad (SE), ratas de edad avanzada + anabolizantes (SA), ratas de edad avanzada + ER (T) y ratas de edad avanzada + ER + anabolizante (TA). Resultados: Para el músculo sóleo, el grupo SE mostró una disminución en el porcentaje de capilares en comparación con el grupo SC. Los grupos SA, T y TA presentaron aumento del volumen de capilares en comparación con el SC. Por otro lado, para el músculo extensor largo de los dedos (ELD), los grupos SA, T y TA mostraron menor volumen y menor número de capilares en comparación con los grupo SC y SE. El músculo ELD de los grupos T y TA presentó 70% menos capilares que el sóleo. La densidad numérica y volumétrica y la proporción de capilares por fibra muscular no se alteraron significativamente por ninguna de las intervenciones. El área de sección transversal (AST) del músculo sóleo de los grupos SA, T y TA fue estadísticamente diferente que el grupo SC. El AST del sóleo fue mayor en los grupos TA y T que en los grupos SC, SE y SA, y el AST del ELD fue mayor en el grupo TA en comparación con todos los demás grupos. El grupo TA tuvo valores más altos que los grupos SE, SA y T. Conclusión: El tipo de intervención utilizada no afecta a ninguna variable medida del perfil capilar. Sin embargo, el uso de esteroides anabolizantes y/o ER tendió a reducir la densidad capilar en el músculo ELD.