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1.
Front Physiol ; 15: 1371839, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38694209

RESUMO

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.

2.
J Physiol Sci ; 74(1): 10, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365576

RESUMO

BACKGROUND/OBJECTIVES: Myocardial infarction (MI) frequently leads to cardiac remodeling and failure with impaired life quality, playing an important role in cardiovascular deaths. Although physical exercise is a well-recognized effective non-pharmacological therapy for cardiovascular diseases, the effects of strength training (ST) on the structural and functional aspects of cardiac remodeling need to be further documented. In this study, we aimed to investigate the role of a linear block ST protocol in the rat model of MI. METHODS AND RESULTS: After 6 weeks of MI induction or sham surgery, male adult rats performed ST for the following 12 weeks. The ladder-based ST program was organized in three mesocycles of 4 weeks, with one load increment for each block according to the maximal carrying load test. After 12 weeks, the infarcted-trained rats exhibited an increase in performance, associated with reduced cardiac hypertrophy and pulmonary congestion compared with the untrained group. Despite not changing MI size, the ST program partially prevented cardiac dilatation and ventricular dysfunction assessed by echocardiography and hemodynamics, and interstitial fibrosis evaluated by histology. In addition, isolated cardiac muscles from infarcted-trained rats had improved contractility parameters in a steady state, and in response to calcium or stimuli pauses. CONCLUSIONS: The ST in infarcted rats increased the capacity to carry mass, associated with attenuation of cardiac remodeling and pulmonary congestion with improving cardiac function that could be attributed, at least in part, to the improvement of myocardial contractility.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Treinamento Resistido , Humanos , Ratos , Masculino , Animais , Treinamento Resistido/métodos , Remodelação Ventricular , Ratos Wistar , Insuficiência Cardíaca/tratamento farmacológico , Miocárdio/patologia , Infarto do Miocárdio/tratamento farmacológico , Cardiomegalia , Colágeno
3.
Acta ortop. bras ; 31(spe1): e253655, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1429581

RESUMO

ABSTRACT Objectives: To present the functional outcomes, through the first case series in our country, of patients with thoracolumbar burst fractures (A3,A4), submitted to short posterior fixation, without arthrodesis and without removal of the implants, until the end of the minimum follow-up of one year. Methods: Fifty five patients consecutively treated between January/2010 and January/2019 were evaluated through medical records and imaging exams. Radiographic analysis was performed by mea suring local and segmental kyphosis using the Cobb method. Functional assessment was analyzed using the non-specific SF-36 questionnaire and the 1983 Denis pain and work-specific questionnaire, applied after 12 months of follow-up. Results: With a loss of five patients (9%), 22 (44%) patients reported having minimal and occasional pain and 8 (16%) patients reported having no pain. Three (6%) patients responded that they were completely incapacitated. Patients had a mean score of 73.16 points in the SF-36 domains. There was a significant reduction in kyphosis in 12 months (9.1±5.2 [min-max 0-22]) compared to the preoperative period (14.9±7.8 [min-max 0-32]) ( p≤0.01). One patient required implant removal due to the symptomatic prominence of the implant. Conclusion: This case series suggests that the technique leads to satisfactory functional results, without implant failure or significant kyphosis after a minimum follow-up of 12 months of treatment. Evidence Level IV; Case series.


RESUMO Objetivo: Apresentar os desfechos funcionais, mediante primeira série de casos no nosso meio, de pacientes com fratura toracolombar do tipo explosão (A3, A4), submetidos a fixação posterior curta, sem artrodese e sem retirada dos implantes, até o final do acompanhamento mínimo de um ano. Métodos: Foram avaliados, por meio de prontuários e exames de imagem, 55 pacientes consecutivamente tratados entre Janeiro/2010 e Janeiro/2019. A análise radiográfica foi realizada medindo a cifose local e segmentar, pelo método de Cobb. A avaliação funcional analisada por meio do questionário inespecífico SF-36 e questionário específico de dor e trabalho de Denis de 1983, aplicados após os 12 meses de seguimento. Resultados: Com perda de cinco pacientes (9%), 22 (44%) pacientes relataram ter dor mínima e ocasional e 8 (16%) pacientes responderam não ter dor. Três (6%) pacientes responderam que estavam completamente incapacitados. Os pacientes tiveram uma pontuação média de 73,16 pontos nos domínios do SF-36. Houve redução significativa da cifose em 12 meses (9,1±5,2 [min-máx 0-22]) na comparação com o pré-operatório (14,9±7,8 [min-máx 0-32]) (p≤0,01). Um paciente necessitou de retirada do implante em razão da proeminência sintomática do implante. Conclusão: Esta série de casos sugere que a técnica leva a resultados funcionais satisfatórios, sem falha do implante ou cifose pós-traumática após acompanhamento mínimo de 12 meses de tratamento. Nível de Evidência IV; Série de casos.

4.
Physiol Behav ; 255: 113921, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35872038

RESUMO

Neuropsychological stress induced by misleading information can limit human performance, possibly by early central fatigue mechanisms. In this study, we investigated the impact caused by prescribing misleading intensities of resistance exercise on acute electroencephalogram (EEG) and electromyogram (EMG) responses and the total number of repetitions to exhaustion. Collegiate female students performed three sets of biceps curls to exhaustion. The actual intensity for all sets was set at 65% 1-Repetition Maximum (1-RM). However, participants were deceptively informed that the intensities were 60%, 65%, or 70% 1-RM. The number of repetitions to fatigue and the magnitude of EEG and EMG signals were analyzed. The number of repetitions to exhaustion was significantly lower in greater announced intensities (18.11 ± 8.44) compared to lower (29.76 ± 16.28; p = 0.017) and correctly (27.82 ± 11.01; p = 0.001) announced intensity. The correlation between frontal and motor-cortex signals was significant in lower (r = 0.72, p = 0.001) and higher (r = 0.64, p = 0.005) announced intensities. The median and mean frequencies of EMG signal and Root Mean Square (RMS) did not show any significant difference between sets, but the peak-to-peak range (PPR) of biceps EMG signals was significantly higher in lower intensity (0.145 ± 0.042) when compared with higher (0.104 ± 0.044; p = 0.028) or correctly (0.126 ± 0.048; p = 0.037) announced intensity. It seems that deceptive information regarding the mass of an object could affect the number of repetitions to exhaustion and PPR to cover muscle capacity in endurance-type strength training.


Assuntos
Treinamento Resistido , Eletromiografia , Fadiga , Feminino , Humanos , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia
5.
Tissue Cell ; 75: 101741, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35074725

RESUMO

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.


Assuntos
Treinamento Resistido , Propionato de Testosterona , Animais , Humanos , Hipertrofia , Masculino , Músculo Esquelético , Ratos , Ratos Wistar , Testosterona , Propionato de Testosterona/farmacologia
6.
Exp Brain Res ; 240(3): 887-896, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35075497

RESUMO

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.


Assuntos
Treinamento Resistido , Animais , Humanos , Bainha de Mielina , Nervo Radial , Ratos , Ratos Wistar , Nervo Isquiático
7.
Tissue Cell ; 75: 101725, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35016105

RESUMO

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.


Assuntos
Treinamento Resistido , Animais , Humanos , Hipertrofia , Músculo Esquelético , Ratos , Ratos Wistar , Treinamento Resistido/métodos , Roedores
9.
Mol Neurobiol ; 58(12): 6670-6683, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34608606

RESUMO

Neuromuscular adaptations are essential for improving athletic performance. However, little is known about the effect of different endurance training protocols and their subsequent detraining on the gene expression of critical factors for neuromuscular synaptic transmission. Therefore, this study investigated the effects of endurance training (high-intensity interval training [HIIT], continuous [cEND], mixed interval [Mix], and all protocols combined [Comb]) and detraining on performance and gene expression (GE) of the alpha-1a, synaptotagmin II (Syt-II), synaptobrevin II (Vamp2), and acetylcholinesterase (AChE) in the gastrocnemius and soleus of Wistar rats. Eighty rodents were randomly divided into control, HIIT, cEND, Mix, Comb, and detraining groups. The rodents trained for 6 weeks (5 × /week), followed by 2 weeks of detraining. Performance improved in all training groups and decreased following detraining (p < 0.05), except HIIT. In the gastrocnemius, alpha-1a GE was upregulated in the Mix. Syt-II and AChE GE were upregulated in HIIT, Mix, and Comb. Vamp2 GE was upregulated in all groups. In the soleus, alpha-1a GE was upregulated in HIIT, Mix, and Comb. Syt-II and Vamp2 GE were upregulated in all groups. AChE GE was upregulated in cEND, Mix, and Comb. Detraining downregulated mostly the gene expression in the skeletal muscles. We conclude that training intensity appears to be a key factor for the upregulation of molecules involved in neuromuscular synaptic transmission. Such changes occur to be involved in improving running performance. On the other hand, detraining negatively affects synaptic transmission and performance.


Assuntos
Cálcio/metabolismo , Exocitose/fisiologia , Músculo Esquelético/metabolismo , Junção Neuromuscular/metabolismo , Condicionamento Físico Animal/métodos , Regulação para Cima , Acetilcolinesterase/metabolismo , Animais , Ratos , Ratos Wistar , Sinaptotagminas/metabolismo , Proteína 2 Associada à Membrana da Vesícula/metabolismo
10.
Physiol Rep ; 8(17): e14502, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32889774

RESUMO

This study aimed to review the effects of ladder-based resistance training (LRT) on muscle hypertrophy and strength in rodents through a systematic review with meta-analysis. We systematically searched PubMed/Medline, SportDiscuss, Scopus, Google Scholar, Science Direct, and Scielo database on May 18, 2020. Thirty-four studies were included measuring total (mCSA) or mean muscle fibers cross-sectional area (fCSA) or maximum load-carrying capacity (MLCC) or muscle mass (MM). About the main results, LRT provides sufficient mechanical stimulation to increase mCSA and fCSA. Meta-analysis showed a significant overall effect on the fCSA (SMD 1.89, 95% CI [1.18, 2.61], p < .00001, I2  = 85%); however, subgroup analysis showed that some muscle types might not be hypertrophied through the LRT. Meta-analysis showed a significant training effect on the MM (SMD 0.92, 95% CI [0.52, 1.32], p < .00001, I2  = 72%). Sub-group analysis revealed that soleus (SMD 1.32, 95% CI [0.11, 2.54], p = .03, I2  = 86%) and FHL (SMD 1.92, 95% CI [1.00, 2.85], p < .0001, I2  = 71%) presented significant training effects, despite moderate heterogeneity levels (I2  = 72%). MLCC increases considerably after a period of LRT, regardless of its duration and the characteristics of the protocols (SMD 12.37, 95% CI [9.36, 15.37], p < .00001, I2  = 90%). Through these results, we reach the following conclusions: (a) LRT is efficient to induce muscle hypertrophy, although this effect varies between different types of skeletal muscles, and; (b) the ability of rodents to carry load increases regardless of the type and duration of the protocol used.


Assuntos
Músculo Esquelético/fisiologia , Condicionamento Físico Animal/métodos , Animais , Hipertrofia/etiologia , Camundongos , Força Muscular , Músculo Esquelético/patologia , Condicionamento Físico Animal/efeitos adversos , Ratos
11.
Sci Rep ; 10(1): 14124, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32839490

RESUMO

The present study shows chronic adjustments in the myotendinous junction (MTJ) in response to different ladder-based resistance training (LRT) protocols. Thirty adult male Wistar rats were divided into groups: sedentary (S), calisthenics (LRT without additional load [C]), and resistance-trained (LRT with extra weight [R]). We demonstrated longer lengths of sarcoplasmatic invaginations in the trained groups; however, evaginations were seen mainly in group R. We showed a greater thickness of sarcoplasmatic invaginations in groups C and R, in addition to greater evaginations in R. We also observed thinner basal lamina in trained groups. The support collagen layer (SCL) adjacent to the MTJ and the diameters of the transverse fibrils were larger in R. We also discovered a niche of telocytes in the MTJ with electron micrographs of the plantar muscle and with immunostaining with CD34+ in the gastrocnemius muscle near the blood vessels and pericytes. We concluded that the continuous adjustments in the MTJ ultrastructure were the result of tissue plasticity induced by LRT, which is causally related to muscle hypertrophy and, consequently, to the remodeling of the contact interface. Also, we reveal the existence of a collagen layer adjacent to MTJ and discover a new micro anatomic location of telocytes.


Assuntos
Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/fisiologia , Condicionamento Físico Animal/fisiologia , Treinamento Resistido/métodos , Retículo Sarcoplasmático/fisiologia , Telócitos/fisiologia , Adaptação Fisiológica/fisiologia , Junções Aderentes/fisiologia , Animais , Membrana Basal/fisiologia , Adesão Celular , Movimento Celular/fisiologia , Junções Célula-Matriz/fisiologia , Colágeno/metabolismo , Masculino , Ratos , Ratos Wistar , Comportamento Sedentário
12.
Histochem Cell Biol ; 154(6): 621-628, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32797254

RESUMO

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.


Assuntos
Terapia por Exercício , Placa Motora/metabolismo , Músculo Esquelético/metabolismo , Junção Neuromuscular/metabolismo , Animais , Masculino , Ratos , Ratos Wistar
13.
Mol Biol Rep ; 47(7): 5305-5314, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32621116

RESUMO

The neuromuscular junction underwent adaptations to meet the demands of muscles following increased muscle activity. This study aimed to investigate the effects of high-intensity interval training (HIIT), endurance training (END), and mixed interval training (MIX) on the gene expression of the calcitonin gene-related peptide-α (CGRP-α), CGRP receptor, nicotinic acetylcholine receptors (nAchR)-ß and glial-derived neurotrophic factor (GDNF) among different muscle types. Male Wistar rats were randomly divided into four groups: Control (n = 8), END (n = 8), HIIT (n = 8), and MIX (n = 8). The animals run each training protocol for 8 weeks (five sessions/week). Forty-eight hours after the last training session, the muscles gastrocnemius and soleus were excised under the sterilized situation. After collection, the material was prepared for RNA extraction, Reverse Transcriptase reaction, and qPCR assay. The HIIT training up-regulated the CGRP-α (p < 0.01), CGRP-Rec (p < 0.01), and GDNF (p < 0.01) in soleus as well as the nAchR-ß (p < 0.01) and GDNF (p < 0.01) in gastrocnemius muscles. END training down-regulated the gene expression of CGRP-α (p < 0.01), and nAchR-ß (p < 0.01) in gastrocnemius but up-regulated nAchR-ß (p = 0.037) in soleus and GDNF (p < 0.01) in gastrocnemius muscles. MIX training did not show any significant up or down-regulation. The endurance performance of HIIT and MIX groups was higher than the END group (p < 0.01). All studied genes up-regulated by HIIT training in a muscle type-specific manner. It seems that the improvement of some synaptic indices induced by HIIT resulted in the improvement of endurance performance.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Músculo Esquelético/metabolismo , Condicionamento Físico Animal/métodos , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/genética , Receptores Nicotínicos/metabolismo , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Masculino , Músculo Esquelético/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Receptores Nicotínicos/genética
14.
Microsc Res Tech ; 83(10): 1190-1197, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32500573

RESUMO

The myofibrillary types establish to the skeletal muscle functional and adaptive properties that influence the sarcomeric arrangement during muscle contraction and may have repercussions on an important related force transmission region of the locomotor apparatus, the myotendinous junction (MTJ). This study aimed to describe changes in myofibrillary type and sarcomeric lengths in the belly muscle and MTJ of the soleus and plantaris muscles associated with training protocols in vertical ladder. Thirty adults male Wistar rats were divided into three groups (n = 10): Control (CTR), No-load Training (NLT), and Load Training (LT). Morphoquantitative analysis of different fibers types and sarcomere lengths were performed in distinct regions of plantaris and soleus muscles. In the plantaris muscle with both trainings, there was an increase in the cross-sectional area (CSA) in Type I and II fibers (p < .0001) while sarcomeric lengths revealed greater lengths in the proximal and distal sarcomeres of NLT, although in the LT we found greater lengths in the belly and MTJ sarcomeres. The soleus muscle showed an increase in CSA muscle fiber only in the NLT (p < .0001) and revealed alterations in belly and MTJ sarcomere lengths with training. We concluded that plantaris muscle has an adaptive effect directly associated with training load, with hypertrophy in both trainings and sarcomere length inverse from belly and MTJ, in LT associated with increased force generation and transmission at the MTJ, although soleus muscle has a lower adaptive response to training stimuli with variation in the belly and distal sarcomere of the MTJ.


Assuntos
Sarcômeros , Tendões , Animais , Masculino , Fibras Musculares Esqueléticas , Músculo Esquelético , Ratos , Ratos Wistar
15.
J Hypertens ; 38(1): 73-81, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31335510

RESUMO

BACKGROUND AND METHOD: This study evaluated the effects of a linear block strength training programme on the parameters of cardiac remodelling in spontaneously hypertensive rats. Thirty-nine rats were equally distributed in four groups: normotensive sedentary, normotensive trained, hypertensive sedentary and hypertensive trained. The strength training protocol was organized in three mesocycles of 4 weeks, with an increase in the training load organized in a linear fashion for each block, considering the weight established in the maximum loaded load test. The following parameters were evaluated: ventricular function assessed by echocardiogram, caudal blood pressure, ventricular haemodynamics and cardiac masses. Two-way analysis of variance was used to determine the differences between the group and time. RESULTS: After 12 weeks of training, the hypertensive trained group presented the following results: increased muscle strength, reduced blood pressure, reduced heart rate, isovolumetric relaxation time and total collagen content, with increased cardiac function, without promoting changes in the mass and nuclear volume of cardiomyocytes. Also, blood pressure reduction seems to be associated with both muscle strength adjustments and total load progress. CONCLUSION: The findings of this study showed that the training programme carried out attenuated systemic arterial pressure and preserved the ventricular function of spontaneously hypertensive rats without cardiac mass change.


Assuntos
Pressão Sanguínea/fisiologia , Hipertensão/fisiopatologia , Condicionamento Físico Animal/fisiologia , Animais , Colágeno/metabolismo , Miocárdio/química , Miocárdio/citologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Ratos , Ratos Endogâmicos SHR , Função Ventricular/fisiologia
16.
Aging Male ; 23(4): 251-256, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29856246

RESUMO

Several studies have demonstrated that alcohol consumption can decrease bone density and alter its structure. However, most of the studies did not investigate the effects of specific alcoholic beverages. This study determined the effects of chronic consumption of cachaça (a Brazilian beverage containing alcohol) on body weight (BW), tibia bone density and on the tibia collagen density in middle-aged Wistar rats. Rats with 9 months old were submitted for 100 days, to a liquid diet of cachaça diluted in water with a progressive and controlled concentration (10°GL, 15°GL, 20°GL, 25°GL, and 30°GL). Chronic cachaça intake produced a significant decrease in BW and altered bone remodeling, decreasing trabecular bone density. In chronic cachaça-treated group (CT), the production of collagen fibers in bone tissue has predominantly green birefringence. It appears that they are immature fibers that do not exist in the control group, in which there are standard predominantly yellowish mature fibers. In conclusion, chronic cachaça consumption affects the structure of the tibial bone of middle-aged rats by decreasing the bone density and reducing the density of mature collagen fibers.


Assuntos
Bebidas Alcoólicas/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Colágeno/efeitos dos fármacos , Etanol/efeitos adversos , Tíbia/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Etanol/farmacologia , Distribuição Aleatória , Ratos , Ratos Wistar , Tíbia/metabolismo
18.
Rev. bras. med. esporte ; 25(6): 503-508, Nov.-Dec. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1042363

RESUMO

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.

19.
Front Physiol ; 9: 823, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30018570

RESUMO

Several studies have demonstrated an acute and chronic increase of brain-derived neurotrophic factor (BDNF) in relation to different types of physical exercise. Currently, many individuals seek physical training strategies that present different types of stimulation and volume/intensity. Thus, the extreme conditioning methodology has gained great notoriety in the scientific and non-scientific environment. Knowing that BDNF values increase in an effort-dependent manner, it is necessary to study the effects of this strategy on BDNF levels. This study aimed to evaluate the acute response of BDNF in trained men submitted to an extreme conditioning program (ECP) session. Ten volunteers underwent an acute ECP session using the "as many reps as possible" (WOD-AMRAP) method, including three types of exercise (clean, wall ball and double or single-unders) for 9 min. BDNF was measured in the plasma, being collected baseline and immediately after the session. Total load of the clean exercise was five times greater than wall ball exercise (p < 0.05; 2096.1 ± 387.4 kg vs 415.8 ± 81.03 kg), which influenced little in the total load (p < 0.05, 2511.9 ± 358.52 kg) used. For the total volume, practitioners averaged 1.7 times more repetitions in the wall ball exercise compared to clean (46.2 ± 9 vs 29.5 ± 3.8 repetitions). The volunteers averaged 75.7 ± 12.6 double-unders repetitions, bringing the total volume of training to 151.4 ± 23.7 repetitions. Regarding the BDNF values, there was a significant difference (p = 0.05) between the pre- vs post-moments (11209.85 ± 1270.4 vs 12132.96 ± 1441.93 pg/ml). Effect size for this change as moderate (ES = 0.79). We found a positive correlation between total volume of clean exercise and delta BDNF values (p = 0.049). In conclusion, a single extreme conditioning session, through the practice of the WOD-AMRAP method, is capable of increasing the acute concentrations of plasma BDNF. In practical terms, we may suggest that future studies evaluate the effect of ECP as a strategy in the treatment of disorders associated with central degenerative changes.

20.
Aging Male ; 21(1): 60-64, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28696823

RESUMO

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.


Assuntos
Envelhecimento/fisiologia , Fígado/anatomia & histologia , Fígado/fisiologia , Treinamento Resistido , Animais , Glicemia/metabolismo , Modelos Animais de Doenças , Humanos , Fígado/irrigação sanguínea , Masculino , Ratos , Ratos Wistar
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