RESUMO
Exercise training is increasingly promoted for physical and mental health and represents a major factor in both primary and secondary prevention of cardiovascular (CV) diseases. The beneficial effects of exercise, in part, can be ascribed to adaptations of neural CV regulation through several mechanisms. In this article, we summarize how exercise training affects neural CV regulation and outline the plasticity of neural network in the continuum from cardiac patients to elite athletes.
Assuntos
Sistema Nervoso Autônomo/fisiologia , Doenças Cardiovasculares/prevenção & controle , Sistema Cardiovascular , Exercício Físico/fisiologia , Adaptação Fisiológica , Atletas , Humanos , Rede Nervosa , Plasticidade NeuronalRESUMO
The healing of a muscle injury is a complex and dynamic process characterized by different overlapping phases resulting in the restoration of the anatomic continuity and function. This process, triggered by the tissue injury itself, is modulated by different growth factors capable of directing the recruitment, duplication, activation, and differentiation of different cell types. This key role played by different growth factors is the basis of the use of platelet-rich plasma in several circumstances, all of them characterized by the need of activating or ameliorating the process of tissue repair. There is an extensive documentation of in vitro and in vivo studies demonstrating the safety and efficacy of growth factors in the muscle healing process. Unfortunately, for many different reasons, experimental results are usually difficult to interpret, clinical results are controversial, and the relevance of use is still debatable. The present article aims to review the available scientific literature with particular focus on actual clinical applications.
Assuntos
Traumatismos em Atletas/terapia , Músculo Esquelético/lesões , Plasma Rico em Plaquetas , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/fisiologiaRESUMO
The coronavirus disease (COVID-19) pandemic has had an unprecedent impact on the world of sport and society at large. Many of the challenges with respect to integrity previously facing competitive sport have been accentuated further during the pandemic. Threats to the integrity of sporting competition include traditional doping, issues of technological fairness, and integration of transgender and intersex athletes in elite sport. The enforced lull in competitive sport provides an unprecedented opportunity for stakeholders in sport to focus on unresolved integrity issues and develop and implement long-lasting solutions. There needs to be a concerted effort to focus on the many technological innovations accelerated by and perfected during COVID-19 that have enabled us to work from home, such as teaching students on-line, applications for medical advice, prescriptions and referrals, and treating patients in hospitals/care homes via video links and use these developments and innovations to enhance sport integrity and anti-doping procedures. Positive sports integrity actions will require a considered application of all such technology, as well as the inclusion of "omics" technology, big data, bioinformatics and machine learning/artificial intelligence approaches to modernize sport. Applications include protecting the health of athletes, considered non-discriminative integration of athletes into elite sport, intelligent remote testing to improve the frequency of anti-doping tests, detection windows, and the potential combination with omics technology to improve the tests' sensitivity and specificity in order to protect clean athletes and deter doping practices.
Assuntos
COVID-19 , Dopagem Esportivo , Inteligência Artificial , Atletas , Humanos , Pandemias , SARS-CoV-2RESUMO
In athletes, spectral analysis of HR variability (HRV) has been shown capable to detect the adaptational changes in sympatho-vagal control attending physical training. So far, studies investigated autonomic nervous system (ANS) changes occurring with endurance training, whereas adaptations to markedly different exercise modes, for example, strength training, have never been investigated. We assessed the changes in cardiac ANS parameters during long-term training in weight lifters of the Italian team preparing for the European Championship, where athletes competed for obtaining the pass for Olympic Games. We investigated nine athletes. Subject trained 3 sessions/day, 6 days a week. The intensity of strength exercises varied from 70% to 95% 1 RM. Training load (TL) was calculated as: volume (min) × intensity (%1RM).All ANS parameters were significantly and highly correlated on an individual basis to the dose of exercise with a second-order regression model (r2 ranged from 0.96 to 0.99; P < 0.001). The low-frequency (LF) component of HRV and LF/HF ratio showed an initial increase with the progression of TL and then a decrease, resembling a bell-shaped curve with a minimum at the highest TL. The high-frequency (HF) component of HRV and R-R interval showed a reciprocal pattern, with an initial decrease with progression of TL followed by an increase, resembling an U-shaped curve with a maximum at the highest TL. These adaptations were at the opposite to those previously reported in endurance athletes. These results suggest that in Olympic weight lifters, ANS adaptations to training are dose-related on individual basis and that ANS adaptations are mainly sport-specific.
Assuntos
Adaptação Fisiológica/fisiologia , Sistema Nervoso Autônomo/fisiologia , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Levantamento de Peso/fisiologia , Adulto , Eletrocardiografia , Feminino , Humanos , Masculino , Resistência Física/fisiologia , Treinamento Resistido , Adulto JovemRESUMO
BACKGROUND: There is abundant evidence suggesting that growth factors may play a key role in the healing process, especially in the early stages of inflammation. Despite the reported clinical successes with the use of growth factors there is still a lack of knowledge on the biological mechanism underlying the activity of platelet-rich plasma during the process of muscle healing. The aim of this study was to analyse the early effects of platelet- rich plasma in an easily reproducible animal model. MATERIALS AND METHODS: Wistar male adult rats (n=102) were used in this study. The muscle lesion was created with a scalpel in the flexor sublimis muscles. Platelet-rich plasma was applied immediately after surgery. Treated, untreated and contralateral muscles were analysed by morphological evaluation and western blot assay. RESULTS: Leucocyte infiltration was significantly greater in muscles treated with platelet-rich plasma than in both untreated and contralateral muscles. The latter showed greater leucocyte infiltration when compared to the untreated muscles. Platelet-rich plasma treatment also modified the cellular composition of the leucocyte infiltration leading to increased expression of CD3, CD8, CD19 and CD68 and to decreased CD4 antigen expression in both platelet-rich plasma treated and contralateral muscles. Blood vessel density and blood vessel diameters were not statistically significantly different between the three groups analysed. DISCUSSION: The results of this study showed that treatment with platelet-rich plasma magnified the physiological early inflammatory response following a muscle injury, modifying the pattern of cellular recruitment. Local platelet-rich plasma treatment may exert a direct or, more plausibly, indirect systemic effect on healing processes, at least in the earliest inflammatory phase.
Assuntos
Músculo Esquelético/lesões , Plasma Rico em Plaquetas , Cicatrização/efeitos dos fármacos , Animais , Antígenos CD/biossíntese , Antígenos CD/genética , Remoção de Componentes Sanguíneos , Quimiotaxia de Leucócito , Regulação da Expressão Gênica , Leucócitos/metabolismo , Leucócitos/patologia , Masculino , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/patologia , Miosite/etiologia , Miosite/terapia , Neovascularização Fisiológica , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Regulação para CimaRESUMO
Platelet-rich plasma (PRP) has received increasing interest in applied medicine, being widely used in clinical practice with the aim of stimulating tissue healing. Despite the reported clinical success, there is still a lack of knowledge when considering the biological mechanisms at the base of the activity of PRP during the process of muscle healing. The aim of the present study was to verify whether the local delivery of PRP modulates specific molecular events involved in the early stages of the muscle regeneration process. The right flexor sublimis muscle of anesthetized Wistar rats was mechanically injured and either treated with PRP or received no treatment. At day 2 and 5 after surgery, the animals were sacrificed and the muscle samples evaluated at molecular levels. PRP treatment increased significantly the mRNA level of the pro-inflammatory cytokines IL-1ß, and TGF-ß1. This phenomenon induced an increased expression at mRNA and/or protein levels of several myogenic regulatory factors such as MyoD1, Myf5 and Pax7, as well as the muscular isoform of insulin-like growth factor1 (IGF-1Eb). No effect was detected with respect to VEGF-A expression. In addition, PRP application modulated the expression of miR-133a together with its known target serum response factor (SRF); increased the phosphorylation of αB-cristallin, with a significant improvement in several apoptotic parameters (NF-κB-p65 and caspase 3), indexes of augmented cell survival. The results of the present study indicates that the effect of PRP in skeletal muscle injury repair is due both to the modulation of the molecular mediators of the inflammatory and myogenic pathways, and to the control of secondary pathways such as those regulated by myomiRNAs and heat shock proteins, which contribute to proper and effective tissue regeneration.