Sports Medicine and Health Science最新文献

The incidence of acute respiratory infections (ARinf), including SARS-CoV-2, in unvaccinated student rugby players during phases from complete lockdown during the COVID-19 pandemic to returning to competition is unknown. The aim of the study was to determine the incidence of ARinf (including SARS-CoV-2) during non-contact and contact phases during the COVID-19 pandemic to evaluate risk mitigation strategies. In this retrospective cohort study, 319 top tier rugby players from 17 universities completed an online questionnaire. ARinf was reported during 4 phases over 14 months (April 2020–May 2021): phase 1 (individual training), phase 2 (non-contact team training), phase 3 (contact team training) and phase 4 (competition). Incidence (per 1 000 player days) and Incidence Ratio (IR) for ‘All ARinf’, and subgroups (SARS-CoV-2; ‘Other ARinf’) are reported. Selected factors associated with ARinf were also explored. The incidence of ‘All ARinf’ (0.31) was significantly higher for SARS-CoV-2 (0.23) vs. ‘Other ARinf’ (0.08) (p ​< ​0.01). The incidence of ‘All ARinf’ (IR ​= ​3.6; p ​< ​0.01) and SARS-CoV-2 (IR ​= ​4.2; p ​< ​0.01) infection was significantly higher during contact (phases 3 ​+ ​4) compared with non-contact (phases 1 ​+ ​2). Demographics, level of sport, co-morbidities, allergies, influenza vaccination, injuries and lifestyle habits were not associated with ARinf incidence. In student rugby, contact phases are associated with a 3–4 times higher incidence of ARinf/SARS-CoV-2 compared to non-contact phases. Infection risk mitigation strategies in the contact sport setting are important. Data from this study serve as a platform to which future research on incidence of ARinf in athletes within contact team sports, can be compared.

The purpose of this research was to use a historical method and core principles from scientific philosophy to explain why mistakes were made in the development of the lactic acidosis construct. On a broader scope, this research explains what science is, why some scientists despite good intention, often get it wrong, and why it takes so long (decades) to correct these errors. Science is a human behaviour that consists of the identification of a problem based on the correct application of prior knowledge, the development of a method to best resolve or test the problem, completion of these methods to acquire results, and then a correct interpretation of the results. If these steps are done correctly there is an increased probability (no guarantee) that the outcome is likely to be correct. Thomas Kuhn proposed that you can understand what science is from how it has been performed, and from his essays he revealed a very dysfunctional form of science that he called ‘normal’ (due the preponderance of its presence) science. Conversely, Karl Popper was adamant that the practice of ‘normal’ science revealed numerous flaws that deviate from fundamental principles that makes science, science. Collectively, the evidence reveals that within the sports medicine and health sciences, as with all disciplines, errors in science are more frequent than you might expect. There is an urgent need to improve how we educate and train scientists to prevent the pursuit of ‘normal’ science and the harm it imparts on humanity.

Myocarditis is a rare cardiomyocyte inflammatory process, typically caused by viruses, with potentially devastating cardiac sequalae in both competitive athletes and in the general population. Investigation into myocarditis prevalence in the Coronavirus disease 2019 (COVID-19) era suggests that infection with Severe acute respiratory syndrome coronavirus (SARS-CoV-2) is an independent risk factor for myocarditis, which is confirmed mainly through cardiovascular magnetic resonance imaging. Recent studies indicated that athletes have a decreased risk of myocarditis after recent COVID-19 infection compared to the general population. However, given the unique nature of competitive athletics with their frequent participation in high-intensity exercise, athletes possess distinct factors of susceptibility for the development of myocarditis and its subsequent severe cardiac complications (e.g., sudden cardiac death, fulminant heart failure, etc.). Under this context, this review focuses on comparing myocarditis in athletes versus non-athletes, owing special attention to the distinct clinical presentations and outcomes of myocarditis caused by different viral pathogens such as cytomegalovirus, Epstein-Barr virus, human herpesvirus-6, human immunodeficiency virus, and Parvovirus B19, both before and after the COVID-19 pandemic, as compared with SARS-CoV-2. By illustrating distinct clinical presentations and outcomes of myocarditis in athletes versus non-athletes, we also highlight the critical importance of early detection, vigilant monitoring, and effective management of viral and non-viral myocarditis in athletes and the necessity for further optimization of the return-to-play guidelines for athletes in the COVID-19 era, in order to minimize the risks for the rare but devastating cardiac fatality.

Decreased mechanical loading after orthopaedic surgery predisposes patients to develop muscle atrophy. The purpose of this review was to assess whether the evidence supports oral protein supplementation can help decrease postoperative muscle atrophy and/or improve patient outcomes following orthopaedic surgery. A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). PubMed (MEDLINE), Embase, Scopus, and Web of Science were searched for randomized controlled trials that assessed protein or amino acid supplementation in patients undergoing orthopaedic surgery. Two investigators independently conducted the search using relevant Boolean operations. Primary outcomes included functional or physiologic measures of muscle atrophy or strength. Fourteen studies including 611 patients (224 males, 387 females) were analyzed. Three studies evaluated protein supplementation after ACL reconstruction (ACLR), 3 after total hip arthroplasty (THA), 5 after total knee arthroplasty (TKA), and 3 after surgical treatment of hip fracture. Protein supplementation showed beneficial effects across all types of surgery. The primary benefit was a decrease in muscle atrophy compared to placebo as measured by muscle cross sectional area. Multiple authors also demonstrated improved functional measures and quicker achievement of rehabilitation benchmarks. Protein supplementation has beneficial effects on mitigating muscle atrophy in the postoperative period following ACLR, THA, TKA, and surgical treatment of hip fracture. These effects often correlate with improved functional measures and quicker achievement of rehabilitation benchmarks. Further research is needed to evaluate long-term effects of protein supplementation and to establish standardized population-specific regimens that maximize treatment efficacy in the postoperative period.

Little is known about the prevalent nationalities among the best-placed athletes participating in “Ironman Hawaii.” Moreover, the age at which athletes achieve their best performances remains unclear. The present study aimed to compare the prevalent nationalities among the athletes, their respective placement among the top five, and the performance difference between the different age groups in ‘Ironman Hawaii’ from 2003 to 2019. A total of 30 354 amateur triathletes were selected from the Obsessed Triathlete (OBSTRI) website. A “TOP 5” division filter was applied for further analysis, resulting in 1 851 athletes being included in this study. Among the male runners, Americans participated the most in Ironman events (39%), followed by Germans (10%). Among female runners, Americans participated the most (54%), followed by Australian runners (8%). Male Americans also featured most among the top five (30%), followed by Germans (16%). Female Americans were the most prevalent among the top five (47%), followed by Australian Americans (10%). There were no significant performance differences (p ​> ​0.05) between the 25–29 and 40–44 age groups for either sex. The 45–49 age group presented significantly worse performance than the 35–39 age group for both sexes (p ​< ​0.001). North Americans were the most performant and frequent participants in “Ironman Hawaii.” The expected performance decline due to aging was observed after 45 years in both sexes.

Muscle atrophy exacerbates disease outcomes and increases mortality, whereas the preservation of skeletal muscle mass and function play pivotal roles in ensuring long-term health and overall quality-of-life. Muscle atrophy represents a significant clinical challenge, involving the continued loss of muscle mass and strength, which frequently accompany the development of numerous types of cancer. Cancer cachexia is a highly prevalent multifactorial syndrome, and although cachexia is one of the main causes of cancer-related deaths, there are still no approved management strategies for the disease. The etiology of this condition is based on the upregulation of systemic inflammation factors and catabolic stimuli, resulting in the inhibition of protein synthesis and enhancement of protein degradation. Numerous necessary cellular processes are disrupted by cachectic pathology, which mediate intracellular signalling pathways resulting in the net loss of muscle and organelles. However, the exact underpinning molecular mechanisms of how these changes are orchestrated are incompletely understood. Much work is still required, but structured exercise has the capacity to counteract numerous detrimental effects linked to cancer cachexia. Primarily through the stimulation of muscle protein synthesis, enhancement of mitochondrial function, and the release of myokines. As a result, muscle mass and strength increase, leading to improved mobility, and quality-of-life. This review summarises existing knowledge of the complex molecular networks that regulate cancer cachexia and exercise, highlighting the molecular interplay between the two for potential therapeutic intervention. Finally, the utility of mass spectrometry-based proteomics is considered as a way of establishing early diagnostic biomarkers of cachectic patients.

Poor cardiorespiratory fitness may mediate vascular impairments at rest and following an acute bout of exercise in young healthy individuals. This study aimed to compare flow mediated dilation (FMD) and vascular augmentation index (AIx75) between young adults with low, moderate, and high levels of cardiorespiratory fitness before and after an acute bout of aerobic exercise. Forty-three participants (22 men; 21 women) between 18 and 29 years of age completed the study. Participants were classified into low, moderate, and high health-related cardiorespiratory fitness groups according to age- and sex-based relative maximal oxygen consumption ($\dot{V}$O₂ max) percentile rankings. FMD was performed using Doppler ultrasound and AIx75 was performed using pulse wave analysis at baseline and 60-min after a 30-min bout of treadmill running at 70% $\dot{V}$O₂ max. A significant interaction (p ​= ​0.047; η_p² ​= ​0.142) was observed, with the moderate fitness group exhibiting a higher FMD post-exercise compared with baseline ([6.7% ​± ​3.1%] vs. [8.5% ​± ​2.8%], p ​= ​0.028; d ​= ​0.598). We found a significant main effect of group for AIx75 (p ​= ​0.023; η_p² ​= ​0.168), with the high fitness group exhibiting lower AIx75 compared to low fitness group ([−10% ​± ​10%] vs. [2% ​± ​10%], respectively, p ​= ​0.019; g ​= ​1.07). This was eliminated after covarying for body fat percentage (p ​= ​0.489). Our findings suggest that resting FMD and AIx75 responses are not significantly influenced by cardiorespiratory fitness, but FMD recovery responses to exercise may be enhanced in individuals with moderate cardiorespiratory fitness levels.

Oxygen uptake ($\dot{V}$ O₂) was measured during a non-exhaustive high-intensity intermittent cross-exercise (HIICE) protocol consisting of four alternating bouts of 20 ​s running (R) and three bouts of bicycle exercise (BE) at ∼160% and ∼170% maximal oxygen uptake ($\dot{V}$ O₂max), respectively, with 10 ​s between-bout rests (sequence R-BE-R-BE-R-BE-R). The $\dot{V}$ O₂ during the last BE ([52.2 ​± ​5.0] mL·kg⁻¹·min⁻¹) was significantly higher than the $\dot{V}$ O₂max of the BE ([48.0 ​± ​5.4] mL·kg⁻¹·min⁻¹, n ​= ​30) and similar to that of running. For clarifying the underlying mechanisms, a corresponding HIICE-protocol with BE and arm cranking ergometer exercise (AC) was used (sequence AC-AC-BE-AC-BE-AC-AC-BE). In some experiments, thigh blood flow was occluded by a cuff around the upper thigh. Without occlusion, the $\dot{V}$ O₂ during the AC ([39.2 ​± ​7.1] mL·kg⁻¹·min⁻¹ [6^th bout]) was significantly higher than the $\dot{V}$ O₂max of AC ([30.2 ​± ​4.4] mL·kg⁻¹·min⁻¹, n ​= ​7). With occlusion, the corresponding $\dot{V}$ O₂ ([29.8 ​± ​3.9] mL·kg⁻¹·min⁻¹) was reduced to that of the $\dot{V}$ O₂max of AC and significantly less than the $\dot{V}$ O₂ without occlusion. These findings suggest that during the last bouts of HIICE may exceed the of the specific exercise, probably because it is a summation of the $\dot{V}$ O₂ for the ongoing exercise plus excess post-oxygen consumption (EPOC) produced by the previous exercise with a higher $\dot{V}$ O₂max.