Background: Given the relationship between reduced pulmonary and respiratory muscle function in neck pain, incorporating breathing exercises into neck pain management may be beneficial. Purpose: The purpose of this study was to investigate the benefits of breathing exercises for treating neck pain. Methods: We searched PubMed (MEDLINE), PEDro, CINAHL, Scopus, and EMBASE databases, up to the 28 of February 2024. Randomized controlled trials evaluating the impact of breathing exercises on reducing pain and disability in both persistent and recent neck pain were selected. A meta-analysis was conducted for each outcome of interest; however, if quantitative methods were not possible, a qualitative synthesis approach was used. The risk of bias was assessed using the Cochrane RoB 2.0 Tool (version 22 August 2019). We used the GRADE approach to judge the certainty of the evidence. Results: Five studies were included. Meta-analysis showed a statistically significant reduction in pain (standardized mean difference (SMD), −10.16; 95% CI: −14.82, −5.50) and disability (SMD, −0.80; 95% CI: −1.49, −0.11), in favor of breathing exercises. Qualitative synthesis for pulmonary functional parameters resulted in a statistically significant improvement for FVC, MIP, MEP, and MVV, in favor of breathing exercises. Conclusions: Breathing exercises showed significant short-term effects in reducing pain and disability for persistent neck pain. They also provided benefits for functional respiratory parameters. However, the evidence certainty is low.

We tested the validity of the state space correspondence (SSC) strategy based on k-nearest neighbor cross-predictability (KNNCP) to assess the directionality of coupling in stochastic nonlinear bivariate autoregressive (NBAR) processes. The approach was applied to assess closed-loop cardiorespiratory interactions between heart period (HP) variability and respiration (R) during a controlled respiration (CR) protocol in 19 healthy humans (aged from 27 to 35 yrs, 11 females) and during active standing (STAND) in 25 athletes (aged from 20 to 40 yrs, all men) and 25 non-athletes (aged from 20 to 40 yrs, all men). Over simulated NBAR processes, we found that (i) the SSC approach can detect the correct causal relationship as the direction leads to better KNNCP from the past of the driver to the future state of the target and (ii) simulations suggest that the ability of the method is preserved in any condition of complexity of the interacting series. Over CR and STAND protocols, we found that (a) slowing the breathing rate increases the strength of the causal relationship in both temporal directions in a balanced modality; (b) STAND is more powerful in modulating the coupling strength on the pathway from HP to R; (c) regardless of protocol and experimental condition, the strength of the link from HP to R is stronger than that from R to HP; (d) significant causal relationships in both temporal directions are found regardless of the level of complexity of HP variability and R. The SSC strategy is useful to disentangle closed-loop cardiorespiratory interactions.

Inspiratory muscle training (IMT) has brought great benefits in terms of improving physical performance in healthy individuals. However, there is no consensus regarding the best training load, as in most cases the maximal inspiratory pressure (MIP) is used, mainly the intensity of 60% of MIP. Therefore, prescribing an IMT protocol that takes into account inspiratory muscle strength and endurance may bring additional benefits to the commonly used protocols, since respiratory muscles differ from other muscles because of their greater muscular resistance. Thus, IMT using critical inspiratory pressure (PThC) can be an alternative, as the calculation of PThC considers these characteristics. Therefore, the aim of this study is to propose a new IMT protocol to determine the best training load for recreational cyclists. Thirty recreational cyclists (between 20 and 40 years old) will be randomized into three groups: sham (SG), PThC (CPG) and 60% of MIP, according to age and aerobic functional capacity. All participants will undergo the following evaluations: pulmonary function test (PFT), respiratory muscle strength test (RMS), cardiopulmonary exercise test (CPET), incremental inspiratory muscle endurance test (iIME) (maximal sustained respiratory pressure for 1 min (PThMAX)) and constant load test (CLT) (95%, 100% and 105% of PThMÁX) using a linear load inspiratory resistor (PowerBreathe K5). The PThC will be calculated from the inspiratory muscle endurance time (TLIM) and inspiratory loads of each CLT. The IMT will last 11 weeks (3 times/week and 55 min/session). The session will consist of 5-min warm-up (50% of the training load) and three sets of 15-min breaths (100% of the training load), with a 1-min interval between them. RMS, iIME, CLT and CPET will be performed beforehand, at week 5 and 9 (to adjust the training load) and after training. PFT will be performed before and after training. The data will be analyzed using specific statistical tests (parametric or non-parametric) according to the data distribution and their respective variances. A p value <0.05 will be considered statistically significant. It is expected that the results of this study will enable the training performed with PThC to be used by health professionals as a new tool to evaluate and prescribe IMT. ClinicalTrials.gov, NCT02984189 . Registered on 6 December 2016.

This systematic review aims to determine if there is a correlation between heart rate variability (HRV) indices and overtraining symptoms (OTS) in soccer players. Conforming to PRISMA guidelines, a search was conducted in February 2024 on Web of Science, PubMed, EMBASE, CINAHL, and SCOPUS. Studies published in English investigating the relationship between HRV parameters and OTS in adult soccer players (>18 years) were included. Accepted study designs were randomized controlled trials, controlled clinical trials, longitudinal studies, prospective studies, cross‐sectional studies, and retrospective studies. Methodological quality was assessed using the Joanna Briggs Institute (JBI) checklist. The search identified 2041 articles, with 19 included postscreening. Most studies examined the correlation between HRV and OTS using linear indices. The average JBI checklist score was 6.3, indicating fair methodological quality. Thirteen studies showed a relationship between linear HRV parameters and OTS, linked to performance/clinical tests, training load, adaptation, fatigue, recovery, or hormonal markers. Thirteen correlations involved HRV frequency domain parameters, and 28 involved HRV time domain characteristics. HRV indexes were linked to OTS markers such as physical performance and psychological aspects in soccer players. Standardization in research methodologies, addressing confounding factors, and exploring additional indexes are crucial in the future.

Background/Objectives: Individuals with autism spectrum disorder (ASD) are at increased risk of developing cardiometabolic diseases. Although physical exercise (PE) has emerged in the literature as an important modulator for reducing such risk, evidence remains unclear. This systematic review aimed to investigate the effects of PE on cardiometabolic health in individuals with ASD. Methods: A systematic review was carried out according to the PRISMA guidelines, from their inception until 18 July 2023, in the following electronic databases: Scopus, Medline, and Web of Science. Studies were included if they focused on ASD patients undergoing physical exercise, assessing cardiometabolic risk, exercise tolerance, and QoL. The following were excluded: non-exercise interventions, additional therapies, non-English studies, and reviews. The methodological quality of the included studies was assessed through the Downs and Black scale. Results: A total of four studies (149 participants) were included in this review, with the average methodological quality being rated as “fair”. Interventions had mixed effects on cardiometabolic health. The BMI (↓2.8 kg/m²), waist circumference (↓1.86 cm), and lipid profiles improved in some cases. VO₂max and HR_baseline showed moderate gains. Secondary outcomes included enhanced endurance, strength, and calorie expenditure, especially in mild ASD. Autistic traits and quality of life improved post-intervention, with better results in the experimental groups. Conclusions: This review indicates that aerobic and functional training improves cardiometabolic health, autistic traits, and QoL in individuals with ASD, particularly in mild cases. Further research is needed to explore the impact of ASD severity on these outcomes.