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Objective: This study aimed to systematically analyze the existing literature and conduct a meta-analysis on the acute effects of apnea on the hematological response by assessing changes in hemoglobin (Hb) concentration and hematocrit (Hct) values. Methods: Searches in Pubmed, The Cochrane Library, and Web of Science were carried out for studies in which the main intervention was voluntary hypoventilation, and Hb and Hct values were measured. Risk of bias and quality assessments were performed. Results: Nine studies with data from 160 participants were included, involving both subjects experienced in breath-hold sports and physically active subjects unrelated to breath-holding activities. The GRADE scale showed a "high" confidence for Hb concentration, with a mean absolute effect of 0.57 g/dL over control interventions. "Moderate" confidence appeared for Hct, where the mean absolute effect was 2.45% higher over control interventions. Hb concentration increased to a greater extent in the apnea group compared to the control group (MD = 0.57 g/dL [95% CI 0.28, 0.86], Z = 3.81, p = 0.0001) as occurred with Hct (MD = 2.45% [95% CI 0.98, 3.93], Z = 3.26, p = 0.001). Conclusions: Apnea bouts lead to a significant increase in the concentration of Hb and Hct with a high and moderate quality of evidence, respectively. Further trials on apnea and its application to different settings are needed.
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Hemoglobinas , Humanos , Apneia/sangue , Apneia/etiologia , Suspensão da Respiração , Hematócrito , Hemoglobinas/análiseRESUMO
The main objective of this clinical practice guideline is to provide a series of recommendations for healthcare and exercise professionals, such as neurologists, physical therapists, and exercise physiologists, regarding exercise prescription for patients with migraine.This guideline was developed following the methodology and procedures recommended in the Appraisal of Guidelines for Research and Evaluation (AGREE). The quality of evidence and strength of recommendations were evaluated with the Scottish Intercollegiate Guidelines Network (SIGN). A systematic literature review was performed and an established appraisal process was employed to rate the quality of relevant scientific research (Grading of Recommendations Assessment, Development, and Evaluation methodology).The evaluation of the current evidence, the elaboration of the grades of recommendation, and their validation show a B grade of recommendation for aerobic exercise, moderate-continuous aerobic exercise, yoga, and exercise and lifestyle recommendations for the improvement of symptoms, disability, and quality of life in patients with migraine. Relaxation techniques, high-intensity interval training, low-intensity continuous aerobic exercise, exercise and relaxation techniques, Tai Chi, and resistance exercise obtained a C grade of recommendation for the improvement of migraine symptoms and disability.
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Terapia por Exercício , Qualidade de Vida , Humanos , Exercício Físico , PrescriçõesRESUMO
Background Trained breath-hold divers have shown physiological adaptations that might improve athletes' aerobic and anaerobic performance. Objective This study aimed to systematically review the scientific literature and perform a meta-analysis to assess the effects of voluntary apnoea training on markers of anaerobic and aerobic performance, such as blood lactate and VO2max. Methods A literature search on three databases (Web of Science, PubMed and SCOPUS) was conducted in March 2022. The inclusion criteria were 1) peer-reviewed journal publication; 2) clinical trials; 3) healthy humans; 4) effects of apnoea training; 5) variables included markers of aerobic or anaerobic performance, such as lactate and VO2max. Results 545 manuscripts were identified following database examination. Only seven studies met the inclusion criteria and were, therefore, included in the meta-analysis. 126 participants were allocated to either voluntary apnoea training (ApT; n = 64) or normal breathing (NB; n = 63). Meta-analysis on the included studies demonstrated that ApT increased the peak blood lactate concentration more than NB (MD = 1.89 mmol*L-1 [95% CI 1.05, 2.73], z = 4.40, p < 0.0001). In contrast, there were no statistically significant effects of ApT on VO2max (MD = 0.89 ml*kg-1*min-1 [95% CI -1.23, 3.01], z = 0.82, p = 0.41). Conclusion ApT might be an alternative strategy to enhace anaerobic performance associated with increased maximum blood lactate; however, we did not find evidence of ApT effects on physiological aerobic markers, such as VO2max. Systematic Review Registration: [PRISMA], identifier [registration number].
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PURPOSE: The main objective was to assess the hypoalgesic effect of adding blood flow restriction (BFR) training with or without motor imagery (MI) to moderate-intensity exercise. The secondary objective was to analyse the correlations of the pain pressure thresholds (PPTs) regarding perceived pain intensity, perceived fatigue, and cuff pressure discomfort. METHODS: A sample of 42 asymptomatic participants were randomly assigned to 3 groups: control group (CG), BFR group, and BFR with MI group. All participants performed a squat exercise at an intensity of 60% of 1RM. For the BFR groups, blood occlusion occurred at 80% of maximal arterial occlusive pressure. Local, bilateral, and distal PPT were assessed pre-intervention, post-intervention and 48 h post-intervention. The perceived fatigue was assessed post-intervention, and pain intensity was assessed only 48 h post-intervention. RESULTS: There were intragroup differences in the CG and BFR + MI group in the local PPT between the pre-intervention and post-intervention measurements (p = 0.039, d= -0.32 and p = 0.009, d= -0.46, respectively) and only in the CG in the bilateral PPT (p = 0.002, d= -0.41). The CG and BFR group showed significant differences at 48 h post-intervention, with a decrease in local PPT (p = 0.009, d = 0.51 and p = 0.049, d = 0.43, respectively) and bilateral PPT (p = 0.004, d = 0.53 and p = 0.021, d = 0.46, respectively). There was a negative moderate correlation between local PPT at the post-intervention time and perceived discomfort of the occlusion device only in the BFR group (r=-0.54, p = 0.045). CONCLUSION: Moderate-intensity resistance training with high occlusion did not generate hypoalgesia but did appear to generate a hyperalgesic response within 48 h after the intervention.
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Treinamento Resistido , Fadiga , Humanos , Hipestesia , Imagens, Psicoterapia , Músculo Esquelético , Fluxo Sanguíneo Regional , Treinamento Resistido/métodos , Método Simples-CegoRESUMO
INTRODUCTION: After a maximal apnoea, breath-hold divers must restore O2 levels and clear CO2 and lactic acid produced. High intensity interval training (HIIT) and inspiratory muscle training (IMT) could be employed with the aim of increasing recovery capacity. This study aimed to evaluate the relative effects of IMT versus HIIT on recovery of peripheral oxygen saturation (SpO2), and also on pulmonary function, inspiratory muscle strength, lactate and heart rate recovery after a maximal dynamic apnoea in breath-hold divers. METHODS: Fifteen breath-hold divers performed two training interventions (IMT and HIIT) for 20 min, three days per week over four weeks in randomised order with a two week washout period. RESULTS: IMT produced a > 3 s reduction in SpO2 recovery time compared to HIIT. The forced expiratory volume in the first second (FEV1) and maximum inspiratory pressure (MIP) were significantly increased in the IMT group compared to HIIT. The magnitude of these differences in favour of IMT was large in both cases. Neither training intervention was superior to the other for heart rate recovery time, nor in peak- and recovery- lactate. CONCLUSIONS: IMT produced a reduction in SpO2 recovery time compared to HIIT after maximal dynamic apnoea. Even a 3 s improvement in recovery could be important in scenarios like underwater hockey where repetitive apnoeas during high levels of exercise are separated by only seconds. IMT also improved FEV1 and MIP, but no differences in lactate and heart rate recovery were found post-apnoea between HIIT and IMT.
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Apneia , Treinamento Intervalado de Alta Intensidade , Suspensão da Respiração , Estudos Cross-Over , Humanos , MúsculosRESUMO
INTRODUCTION: The influence of acute exercise on sensory sensitivity (SS) differs according to the type and duration of exercise performed. In the present study, we assessed changes on SS soon after a maximal dynamic apnoea. METHODS: Thirty-nine experienced male breath-hold divers were recruited. Critical flicker fusion frequency (CFFF) thresholds were used to measure SS. Thresholds were determined before and after a maximal dynamic apnoea. Immediately after surfacing, heart rate and oxygen saturation (SpO2) were recorded for two minutes. RESULTS: After maximal dynamic apnoea, SpO2 was significantly decreased (from mean 97.3% pre-dive to mean 63.1% post-dive; P < 0.0001; η2 P = 0.86), but this acute hypoxaemia did not trigger changes in SS (post-dive value 102% of baseline; P = 0.22; η2 P = 0.03). Pearson correlation analysis revealed a moderate association between SS with swimming speed (r = 0.423) and apnoea time (r = -0.404). CONCLUSIONS: A maximal dynamic apnoea did not produce changes in central nervous system fatigue or cortical arousal. We found no relationship between the hypoxaemia level reached after a maximal apnoea and changes in the CFFF thresholds. This study suggests that the time of exposure to hypoxia during a maximal voluntary apnoea is not enough to produce changes in SS.
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Apneia , Mergulho , Fusão Flicker , Suspensão da Respiração , Mergulho/efeitos adversos , Humanos , Masculino , Oxigênio/administração & dosagem , Oxigênio/efeitos adversosRESUMO
The objective of this study was to determine the effects of high-intensity warm-ups (WUs) on performance, physiological, neuromuscular and biomechanical parameters. Three randomized cross-over 105%vVO2max time limit trials (TLimT) were performed by 11 well-trained runners following three different WU protocols. These included two experimental high-intensity variants and one control WU variant: (i) 9x20-sec level strides (105%vVO2max; 1% gradient) with 60 s of recovery (level); (ii) 6x6-sec uphill strides (105%vVO2max; 5% gradient), with the same recovery (uphill) and (iii) 7 min at 60%vVO2max as control condition (control). The uphill and level WUs resulted in a greater performance during TLimT (160.0±6.62 s and 152.64±10.88 s, respectively) compared to control WUs (144.82±6.60 s). All WU conditions reduced the energy cost (EC) of running, respiratory exchange ratio, and step frequency (SF) after the experimental and control phases of WU, while blood lactate (BLC) increased in uphill and level WUs and decreased in control WUs. Changes in kinematic variables were found without differences between WU conditions during TLimT. BLC rose at conclusion of TLimT without differences between WU conditions. Both high-intensity WUs show a longer TLimT. EC is deteriorated after the high-intensity WU exercise due to a change of substrate utilization, increase of BLC and SF. A long transient phase (18 min) is necessary to avoid impairing the performance.