Repeated Short-Term Bouts of Hyperoxia Improve Aerobic Performance in Acute Hypoxia.

ABSTRACT: Faulhaber, M, Schneider, S, Rausch, LK, Dünnwald, T, Menz, V, Gatterer, H, Kennedy, MD, and Schobersberger, W. Repeated short-term bouts of hyperoxia improve aerobic performance in acute hypoxia. J Strength Cond Res 37(10): 2016-2022, 2023-This study aimed to test the effects of repeated short-term bouts of hyperoxia on maximal 5-minute cycling performance under acute hypoxic conditions (3,200 m). Seventeen healthy and recreationally trained individuals (7 women and 10 men) participated in this randomized placebo-controlled cross-over trial. The procedures included a maximal cycle ergometer test and 3 maximal 5-minute cycling time trials (TTs). TT1 took place in normoxia and served for habituation and reference. TT2 and TT3 were conducted in normobaric hypoxia (15.0% inspiratory fraction of oxygen). During TT2 and TT3, the subjects were breathing through a face mask during five 15-second periods. The face mask was connected through a nonrebreathing T valve to a 300-L bag filled with 100% oxygen (intermittent hyperoxia) or ambient hypoxic air (placebo). The main outcome was the mean power output during the TT. Statistical significance level was set at p < 0.05. The mean power output was higher in the intermittent hyperoxia compared with the placebo condition (255.5 ± 49.6 W vs. 247.4 ± 48.2 W, p = 0.001). Blood lactate concentration and ratings of perceived exertion were significantly lower by about 9.7 and 7.3%, respectively, in the intermittent hyperoxia compared with the placebo condition, whereas heart rate values were unchanged. IH application increased arterial oxygen saturation (82.9 ± 2.6% to 92.4 ± 3.3%, p < 0.001). Repeated 15-second bouts of hyperoxia, applied during high-intensity exercise in hypoxia, are sufficient to increase power output. Future studies should focus on potential dose-response effects and the involved mechanisms.

Doping in Paralympic sport: perceptions, responsibility and anti-doping education experiences from the perspective of Paralympic athletes and parasport coaches.

Introduction: Limited effort has been invested in understanding doping in Paralympic sport. The limited evidence that exists suggests that factors influencing doping in parasport are similar to Olympic sport. However, based on the design and nature of the previous studies, where methods have been mostly limited to qualitative data and prevalence numbers, further research is warranted to extend previous findings. Methods: Informed by current evidence from Paralympic and Olympic sport, we aimed to investigate (1) para-athletes' perceptions of Anti-Doping Rule Violations (ADRVs) and responsibility for them, (2) descriptive norms for doping in parasport (3) perceptions of anti-doping education and legitimacy of anti-doping authorities, and (4) coach engagement in doping prevention and levels of doping confrontation efficacy using a quantitative survey approach. Results: In total, valid survey responses from 126 Paralympic athletes and 35 coaches from four countries (Germany, Austria, Switzerland, UK) were analysed for experience with anti-doping, descriptive norms, anti-doping education, perceived legitimacy, knowledge, and doping confrontation efficacy (coaches only). Across both athletes and coaches, the level of education was generally good and doping willingness was low. Classification cheating was considered a form of doping and seems to be an important issue for athletes and coaches, especially within the UK sample. For 33.3% of the athletes, doping control was their first experience with anti-doping. Coaches' engagement with doping prevention activities and their perceived efficacy to confront doping-related matters appears to be higher compared to Olympic coaches' samples. Discussion: Sport organisations/NADOs in Paralympic sport could use synergies with those organisations in Olympic sport, adopting similar approaches to anti-doping education, also focusing on a balanced communication of doping prevalence numbers and testing figures. Efforts to ensure athletes are educated about anti-doping before they are tested should be upheld. It seems that in para sport, different compared to able-bodied coaches, anti-doping organizations do not have to convince the coaches about their roles (i.e., being responsible for anti-doping education) anymore but can directly build on these resources. Overall, it seems that there are few differences between parasport and able-bodied sports and thus responsible organisations could use the existing programmes in Olympic sport and only adapt special content (e.g., boosting) which is unique to Paralympic athletes.

IOC consensus statement on recommendations and regulations for sport events in the heat.

This document presents the recommendations developed by the IOC Medical and Scientific Commission and several international federations (IF) on the protection of athletes competing in the heat. It is based on a working group, meetings, field experience and a Delphi process. The first section presents recommendations for event organisers to monitor environmental conditions before and during an event; to provide sufficient ice, shading and cooling; and to work with the IF to remove regulatory and logistical limitations. The second section summarises recommendations that are directly associated with athletes' behaviours, which include the role and methods for heat acclimation; the management of hydration; and adaptation to the warm-up and clothing. The third section explains the specific medical management of exertional heat stroke (EHS) from the field of play triage to the prehospital management in a dedicated heat deck, complementing the usual medical services. The fourth section provides an example for developing an environmental heat risk analysis for sport competitions across all IFs. In summary, while EHS is one of the leading life-threatening conditions for athletes, it is preventable and treatable with the proper risk mitigation and medical response. The protection of athletes competing in the heat involves the close cooperation of the local organising committee, the national and international federations, the athletes and their entourages and the medical team.

Low-Molecular-Weight Heparin Resistance and Its Viscoelastic Assessment in Critically Ill COVID-19 Patients.

Critically ill COVID-19 patients present an inflammatory and procoagulant status with a high rate of relevant macro- and microvascular thrombosis. Furthermore, high rates of heparin resistance have been described; yet, individualized anticoagulation by drug monitoring has not been sufficiently researched. We analyzed data from critically ill COVID-19 patients treated at Innsbruck Medical University Hospital with routinely adapted low-molecular-weight heparin (LMWH) doses according to anti-Xa peak levels, and regularly performed ClotPro analyses (a viscoelastic hemostatic whole blood test). A total of 509 anti-Xa peak measurements in 91 patients were categorized as below (<0.008 IU/mL/mg), within (0.008-0-012 IU/mL/mg) or above (> 0.012 IU/mL/mg) expected ranges with respect to the administered LMWH doses. Besides intergroup comparisons, correlations between anti-Xa levels and ClotPro clotting times (CTs) were performed (226 time points in 84 patients). Anti-Xa peak levels remained below the expected range in the majority of performed measurements (63.7%). Corresponding patients presented with higher C-reactive protein and D-dimer but lower antithrombin levels when compared with patients achieving or exceeding the expected range. Consequently, higher enoxaparin doses were applied in the sub-expected anti-Xa range group. Importantly, 47 (51.6%) patients switched between groups during their intensive care unit (ICU) stay. Anti-Xa levels correlated weakly with IN test CT and moderately with Russell's viper venom (RVV) test CT. Critically ill COVID-19 patients present with a high rate of LMWH resistance but with a variable LMWH response during their ICU stay. Therefore, LMWH-anti-Xa monitoring seems inevitable to achieve adequate target ranges. Furthermore, we propose the use of ClotPro's RVV test to assess the coagulation status during LMWH administration, as it correlates well with anti-Xa levels but more holistically reflects the coagulation cascade than anti-Xa activity alone.

High Intensity Concentric-Eccentric Exercise Under Hypoxia Changes the Blood Metabolome of Trained Athletes.

The aim of this study was to determine alterations of the metabolome in blood plasma in response to concentric-eccentric leg exercise performed at a simulated altitude of 3,500 m. To do so, we recruited 11 well-trained subjects and performed an untargeted metabolomics analysis of plasma samples obtained before, 20 min after as well as on day 8 after five sets of maximal, concentric-eccentric leg exercises that lasted 90 s each. We identified and annotated 115 metabolites through untargeted liquid chromatography-mass spectrometry metabolomics and used them to further calculate 20 sum/ratio of metabolites. A principal component analysis (PCA) revealed differences in-between the overall metabolome at rest and immediately after exercise. Interestingly, some systematic changes of relative metabolite concentrations still persisted on day 8 after exercise. The first two components of the PCA explained 34% of the relative concentrations of all identified metabolites analyzed together. A volcano plot indicates that 35 metabolites and two metabolite ratios were significantly changed directly after exercise, such as metabolites related to carbohydrate and TCA metabolism. Moreover, we observed alterations in the relative concentrations of amino acids (e.g., decreases of valine, leucine and increases in alanine) and purines (e.g., increases in hypoxanthine, xanthine and uric acid). In summary, high intensity concentric-eccentric exercise performed at simulated altitude systematically changed the blood metabolome in trained athletes directly after exercise and some relative metabolite concentrations were still changed on day 8. The importance of that persisting metabolic alterations on exercise performance should be studied further.

International Olympic Committee (IOC) consensus statement on acute respiratory illness in athletes part 1: acute respiratory infections.

Acute illnesses affecting the respiratory tract are common and form a significant component of the work of Sport and Exercise Medicine (SEM) clinicians. Acute respiratory illness (ARill) can broadly be classified as non-infective ARill and acute respiratory infections (ARinf). The aim of this consensus is to provide the SEM clinician with an overview and practical clinical approach to ARinf in athletes. The International Olympic Committee (IOC) Medical and Scientific Commission appointed an international consensus group to review ARill (non-infective ARill and ARinf) in athletes. Six subgroups of the IOC Consensus group were initially established to review the following key areas of ARill in athletes: (1) epidemiology/risk factors for ARill, (2) ARinf, (3) non-infective ARill including ARill due to environmental exposure, (4) acute asthma and related conditions, (5) effects of ARill on exercise/sports performance, medical complications/return-to-sport and (6) acute nasal/vocal cord dysfunction presenting as ARill. Several systematic and narrative reviews were conducted by IOC consensus subgroups, and these then formed the basis of sections in the consensus documents. Drafting and internal review of sections were allocated to 'core' members of the consensus group, and an advanced draft of the consensus document was discussed during a meeting of the main consensus core group in Lausanne, Switzerland on 11 to 12 October 2021. Final edits were completed after the meeting. This consensus document (part 1) focusses on ARinf, which accounts for the majority of ARill in athletes. The first section of this consensus proposes a set of definitions and classifications of ARinf in athletes to standardise future data collection and reporting. The remainder of the consensus paper examines a wide range of clinical considerations related to ARinf in athletes: epidemiology, risk factors, pathology/pathophysiology, clinical presentation and diagnosis, management, prevention, medical considerations, risks of infection during exercise, effects of infection on exercise/sports performance and return-to-sport guidelines.

International Olympic Committee (IOC) consensus statement on acute respiratory illness in athletes part 2: non-infective acute respiratory illness.

Acute respiratory illness (ARill) is common and threatens the health of athletes. ARill in athletes forms a significant component of the work of Sport and Exercise Medicine (SEM) clinicians. The aim of this consensus is to provide the SEM clinician with an overview and practical clinical approach to non-infective ARill in athletes. The International Olympic Committee (IOC) Medical and Scientific Committee appointed an international consensus group to review ARill in athletes. Key areas of ARill in athletes were originally identified and six subgroups of the IOC Consensus group established to review the following aspects: (1) epidemiology/risk factors for ARill, (2) infective ARill, (3) non-infective ARill, (4) acute asthma/exercise-induced bronchoconstriction and related conditions, (5) effects of ARill on exercise/sports performance, medical complications/return-to-sport (RTS) and (6) acute nasal/laryngeal obstruction presenting as ARill. Following several reviews conducted by subgroups, the sections of the consensus documents were allocated to 'core' members for drafting and internal review. An advanced draft of the consensus document was discussed during a meeting of the main consensus core group, and final edits were completed prior to submission of the manuscript. This document (part 2) of this consensus focuses on respiratory conditions causing non-infective ARill in athletes. These include non-inflammatory obstructive nasal, laryngeal, tracheal or bronchial conditions or non-infective inflammatory conditions of the respiratory epithelium that affect the upper and/or lower airways, frequently as a continuum. The following aspects of more common as well as lesser-known non-infective ARill in athletes are reviewed: epidemiology, risk factors, pathology/pathophysiology, clinical presentation and diagnosis, management, prevention, medical considerations and risks of illness during exercise, effects of illness on exercise/sports performance and RTS guidelines.

GRADE IT-A Literacy-Based Assessment Tool for Generating Research-Based Assessment Data to Evidence the ImpacT of Anti-doping Education via Athletes' Capability to Make the Right Decision.

The International Standard for Education (ISE) mandates Code Signatories to plan, deliver, and evaluate anti-doping education. Performance-based evaluation of anti-doping education requires alignment between educational goals, content, and defined outcomes. Based on an existentialist teaching and learning philosophy, we aimed to develop and test an anti-doping impact evaluation tool, to assess the impact of anti-doping education on doping awareness, literacy (DAL), perceived trust, and legitimacy. We propose that the impact of anti-doping education is best captured through assessment of situation-specific (social) cognitive mediators of actions that influence athletes' choices in the context of sport-related goals. In phase one, we aimed to develop and test the Generating Research-based Assessment Data to Evidence the ImpacT of anti-doping education (GRADE IT) evaluation tool that comprised a set of social cognitive components: anti-doping knowledge, DAL, perceived trust, and legitimacy of anti-doping (organizations). In phase two we assessed whether anti-doping education impacts knowledge, the three DAL stages (functional, interactive, and critical literacy), perceived trust and legitimacy. Phase one enrolled 986 junior elite athletes, and we showed that all GRADE IT components performed well. After revision of the tool for phase two, we validated the assumption that anti-doping education impacts the likelihood that athletes will make the "right" choice (based on a new set of data from 1,255 junior elite athletes). Comprehensive education was associated with higher scores for all stages of DAL, as well as perceived trust and legitimacy. Even athletes reporting no education had positive scores for all included outcomes, supporting the assumption that most athletes wish to engage in clean sport behaviors and might need anti-doping education not to prevent them from doping, but rather to reinforce their commitment to clean sport. In conclusion, GRADE IT, which is available in 23 languages, is a suitable tool for application to young, emerging athletes to satisfy the ISE requirement for evaluating anti-doping education programs. Researchers and practitioners alike are advised to collect additional data to further validate the tool for adult athletes, and to apply it longitudinally to identify if changes in doping prevention policies have a delayed effect on DAL, perceived trust, and legitimacy.

Environmental factors associated with non-infective acute respiratory illness in athletes: A systematic review by a subgroup of the IOC consensus group on "acute respiratory illness in the athlete".

OBJECTIVES: The aim of this study is to review the evidence available suggesting that environmental conditions represent a risk factor associated with non-infective acute respiratory illness in athletes. DESIGN: Systematic review. METHODS: PubMed, EBSCOhost and Web of Science (1st January 1990-31 July 2020) were searched systematically using keywords related to male and female athletes (i.e. from physically active individuals to elite athletes), aged 15-65 years and a combination of the terms (non-infective acute respiratory illness AND [pollution OR allergies OR climate] AND athletes AND prevalence/incidence/risk factors). RESULTS: A total of seven papers (n = 1567 athletes) addressed our question. Among these, one focused on indoor air pollution, four on chlorinated swimming pool exposure and two on cold air conditions. None was selected for allergies, outdoor air pollution or other climatic conditions. Except rhinitis induced by swimming in chlorinated pools (n = 1), no respiratory disease due to the environment was identified specifically in athletes. The levels of chloramines in swimming pools (n = 2) and air pollutant in arenas (n = 1) were identified as risk factors for rhinitis and respiratory symptoms when exercising. DISCUSSIONS: There is a paucity of data on the prevalence, incidence and risk factors of being acutely exposed to chlorine by-products, air pollution, cold air or altitude on the development of respiratory disease specifically in athletes. Noting the lack of a clear definition of environmentally induced lung disease in athletes, distinct from that of the general population, we addressed the few published management plans to protect athletes' airways for each specific environment.

The Influence of Environmental Hypoxia on Hemostasis-A Systematic Review.

Humans have been ascending to high altitudes for centuries, with a growing number of professional- and leisure-related sojourns occurring in this millennium. A multitude of scientific reports on hemostatic disorders at high altitude suggest that hypoxia is an independent risk factor. However, no systematic analysis of the influence of environmental hypoxia on coagulation, fibrinolysis and platelet function has been performed. To fill this gap, we performed a systematic literature review, including only the data of healthy persons obtained during altitude exposure (<60 days). The results were stratified by the degree of hypoxia and sub-categorized into active and passive ascents and sojourns. Twenty-one studies including 501 participants were included in the final analysis. Since only one study provided relevant data, no conclusions regarding moderate altitudes (1,500-2,500 m) could be drawn. At high altitude (2,500-5,400 m), only small pathophysiological changes were seen, with a possible impact of increasing exercise loads. Elevated thrombin generation seems to be balanced by decreased platelet activation. Viscoelastic methods do not support increased thrombogenicity, with fibrinolysis being unaffected by high altitude. At extreme altitude (5,400-8,850 m), the limited data showed activation of coagulation in parallel with stimulation of fibrinolysis. Furthermore, multiple confounding variables at altitude, like training status, exercise load, fluid status and mental stress, prevent definitive conclusions being drawn on the impact of hypoxia on hemostasis. Thus, we cannot support the hypothesis that hypoxia triggers hypercoagulability and increases the risk of thromboembolic disorders, at least in healthy sojourners.

Thoracolumbar Rotation During Tai Chi Movements-A Biomechanical Analysis of the Entire Peking Style Routine.

The impact of spinal mobility and sagittal spinal shape on the development of balance impairment supports the hypothesis that enhancing spine flexibility results in an improvement in postural balance ability. Therefore, the aim of this study was to investigate whether the range of motion of thoracolumbar rotation during the movements of the Tai Chi Peking style routine is sufficient to improve thoracolumbar flexibility. Three-dimensional kinematic and kinetic data were collected from eight athletes of the German Wushu Federation, while performing all movements of the entire Peking style routine (1) in a competition version corresponding to national/international championships and (2) in a health sport version performed with shorter and higher stances (i.e. a smaller distance between the feet and thus less knee flexion). For each movement the total mean and standard deviation values for the total range of motion of thoracolumbar rotation was calculated. Statistical analysis was performed using the Wilcoxon signed-rank test for paired differences. Eight movements showed major differences (10.12-19.73°) between the two versions. For the remaining movements, only minor differences (0.7-9.56°) were observed. All movements performed on both sides showed no significant lateral differences. Most of the Tai Chi movements, regardless of the performed version, cover a range of motion of thoracolumbar rotation that has the potential to lead to an improvement of thoracolumbal spine flexibility with appropriate training. The most effective single movements (25.97-72.22°) are Brush Knee and Step Forward, Step Back and Repulse Monkey, Grasp the Sparrow's Tail, Wave Hand in the Clouds, and Fair Lady Weaves with Shuttle.

Supplemental O 2 During Recovery Does Not Improve Repeated Maximal Concentric-Eccentric Strength-Endurance Performance in Hypoxia.

ABSTRACT: Dünnwald, T, Morawetz, D, Faulhaber, M, Gatterer, H, Birklbauer, C, Koller, A, Weiss, G, and Schobersberger, W. Supplemental O 2 during recovery does not improve repeated maximal concentric-eccentric strength-endurance performance in hypoxia. J Strength Cond Res 36(11): 3065-3073, 2022-An alpine ski racing training session typically includes repeated bouts of maximal exercise at high altitude. We evaluated whether hyperoxic recovery between 5 sets of high-intensity strength-endurance exercises, which resembled ski racing activity and were performed in hypoxia, has beneficial effects on performance and acid-base status. In this randomized, single blinded crossover study, 15 highly skilled ski athletes (4 f/11 m; 29.7 ± 5.7 years) performed 5 90 seconds flywheel sets (S) in a normobaric hypoxic chamber (3,500 m). The flywheel sets were separated by 4 15-minute recovery periods. During recovery, subjects received either 100% O 2 (hyperoxic setting [HS]) or hypoxic air (nonhyperoxic setting [NHS]; FiO 2 : 0.146). Performance outcomes (e.g., power output [PO], concentric peak power [Con peak ], and eccentric peak power [Ecc peak ]) and physiological parameters (e.g., heart rate, blood gases, and blood lactate) were evaluated. Mean PO, Con peak , and Ecc peak from S1 to S5 did not differ between settings (146.9 ± 45 W and 144.3 ± 44 W, 266.9 ± 80 W and 271.2 ± 78 W, and 271.0 ± 93 W and 274.1 ± 74 W for HS and NHS, respectively; p ≥ 0.05). SpO 2 , PaO 2 , and CaO 2 were higher during recovery in HS than in NHS ( p ≤ 0.001). Lactate levels were significantly lower in the last recovery phase in HS than in NHS ( p = 0.016). Hyperoxic recovery has no impact on performance in a setting resembling alpine ski racing training. Positive effects on arterial oxygen content and cellular metabolism, as indicated by reduced blood lactate levels during recovery in the hyperoxic setting, seem to be insufficient to generate a direct effect on performance.

Practicing Sport in Cold Environments: Practical Recommendations to Improve Sport Performance and Reduce Negative Health Outcomes.

Although not a barrier to perform sport, cold weather environments (low ambient temperature, high wind speeds, and increased precipitation, i.e., rain/water/snow) may influence sport performance. Despite the obvious requirement for practical recommendations and guidelines to better facilitate training and competition in such cold environments, the current scientific evidence-base is lacking. Nonetheless, this review summarizes the current available knowledge specifically related to the physiological impact of cold exposure, in an attempt to provide practitioners and coaches alike with practical recommendations to minimize any potential negative performance effects, mitigate health issues, and best optimize athlete preparation across various sporting disciplines. Herein, the review is split into sections which explore some of the key physiological effects of cold exposure on performance (i.e., endurance exercise capacity and explosive athletic power), potential health issues (short-term and long-term), and what is currently known with regard to best preparation or mitigation strategies considered to negate the potential negative effects of cold on performance. Specific focus is given to "winter" sports that are usually completed in cold environments and practical recommendations for physical preparation.

Wearable and telemedicine innovations for Olympic events and elite sport.

Rapid advances in wearable technologies and real-time monitoring have resulted in major inroads in the world of recreational and elite sport. One such innovation is the application of real-time monitoring, which comprises a smartwatch application and ecosystem, designed to collect, process and transmit a wide range of physiological, biomechanical, bioenergetic and environmental data using cloud-based services. We plan to assess the impact of this wireless technology during Tokyo 2020, where this technology could help characterize the physiological and thermal strain experienced by an athlete, as well as determine future management of athletes during a medical emergency as a result of a more timely and accurate diagnosis. Here we describe some of the innovative technologies developed for numerous sports at Tokyo 2020 ranging from race walking (20 km and 50 km events), marathon, triathlon, road cycling (including the time trial event), mountain biking, to potentially team sports played outdoors. A more symbiotic relationship between sport, health and technology needs to be encouraged that harnesses the unique demands of elite sport (e.g., the need for unobtrusive devices that provide real-time feedback) and serves as medical and preventive support for the athlete's care. The implementation of such applications would be particularly welcome in the field of medicine (i.e., telemedicine applications) and the workplace (with particular relevance to emergency services, the military and generally workers under extreme environmental conditions). Laboratory and field-based studies are required in simulated scenarios to validate such emerging technologies, with the field of sport serving as an excellent model to understand and impact disease.

The questionable benefit of pectus excavatum repair on cardiopulmonary function: a prospective study.

OBJECTIVES: Since the introduction of the minimally invasive technique for repair of pectus excavatum (MIRPE), increasing numbers of patients are presenting for surgery. However, controversy remains regarding cardiopulmonary outcomes of surgical repair. Therefore, the aim of our prospective study was to investigate cardiopulmonary function, at rest and during exercise before surgery, first after MIRPE and then after pectus bar removal. METHODS: Forty-seven patients were enrolled in a prospective, open-label, single-arm, single-centre clinical trial (Impact of Surgical Treatments of Thoracic Deformation on Cardiopulmonary Function) [NCT02163265] between July 2013 and November 2019. All patients underwent a modified MIRPE technique for surgical correction of pectus excavatum (PE), called Minor Open Videoendoscopically Assisted Repair of Pectus Excavatum. The patients underwent pre- and postoperative chest X-ray, three-dimensional volume-rendering computer tomography thorax imaging, cardiopulmonary function tests at rest and during stepwise cycle spiroergometry (sitting and supine position) and Doppler echocardiography. Daily physical activity questionnaires were also completed. RESULTS: The study was completed by 19 patients (15 males, 4 females), aged 13.9-19.6 years at the time of surgery. The surgical patient follow-up was 5.7 ± 7.9 months after pectus bar removal. No significant differences in cardiopulmonary and exercise parameters were seen after placement of the intrathoracic bar, or after pectus bar removal, compared to presurgery. CONCLUSIONS: Our findings indicate that surgical correction of PE does not impair cardiopulmonary function at rest or during exercise. Therefore, no adverse effects on exercise performance should be expected from surgical treatment of PE via the modified MIRPE technique. CLINICAL TRIAL REGISTRATION NUMBER: clinicaltrials.gov [ClinicalTrials.gov number, NCT02163265].

Prehospital management of exertional heat stroke at sports competitions: International Olympic Committee Adverse Weather Impact Expert Working Group for the Olympic Games Tokyo 2020.

OBJECTIVES: This document aimed to summarise the key components of exertional heat stroke (EHS) prehospital management. METHODS: Members of the International Olympic Committee Adverse Weather Impact Expert Working Group for the Olympic Games Tokyo 2020 summarised the current best practice regarding the EHS prehospital management. RESULTS: Sports competitions that are scheduled under high environmental heat stress or those that include events with high metabolic demands should implement and adopt policy and procedures for EHS prehospital management. The basic principles of EHS prehospital care are: early recognition, early diagnosis, rapid, on-site cooling and advanced clinical care. In order to achieve these principles, medical organisers must establish an area called the heat deck within or adjacent to the main medical tent that is optimised for EHS diagnosis, treatment and monitoring. Once admitted to the heat deck, the rectal temperature of the athlete with suspected EHS is assessed to confirm an elevated core body temperature. After EHS is diagnosed, the athlete must be cooled on-site until the rectal temperature is below 39°C. While cooling the athlete, medical providers are recommended to conduct a blood analysis to rule out exercise-associated hyponatraemia or hypoglycaemia, provided that this can be safely performed without interrupting cooling. The athlete is transported to advanced care for a full medical evaluation only after the treatment has been provided on-site. CONCLUSIONS: A coordination of care among all medical stakeholders at the sports venue, during transport, and at the hospital is warranted to ensure effective management is provided to the EHS athlete.

Ethical dilemmas and validity issues related to the use of new cooling technologies and early recognition of exertional heat illness in sport.

The Tokyo 2020 Olympic Games is expected to be among the hottest Games in modern history, increasing the chances for exertional heat stroke (EHS) incidence, especially in non-acclimatised athletes/workers/spectators. The urgent need to recognise EHS symptoms to protect all attendees' health has considerably accelerated research examining the most effective cooling strategies and the development of wearable cooling technology and real-time temperature monitoring. While these technological advances will aid the early identification of EHS cases, there are several potential ethical considerations for governing bodies and sports organisers. For example, the impact of recently developed cooling wearables on health and performance is unknown. Concerning improving athletic performance in a hot environment, there is uncertainty about this technology's availability to all athletes. Furthermore, the real potential to obtain real-time core temperature data will oblige medical teams to make crucial decisions around their athletes continuing their competitions or withdraw. Therefore, the aim of this review is (1) to summarise the practical applications of the most novel cooling strategies/technologies for both safety (of athletes, spectators and workers) and performance purposes, and (2) to inform of the opportunities offered by recent technological developments for the early recognition and diagnosis of EHS. These opportunities are presented alongside several ethical dilemmas that require sports governing bodies to react by regulating the validity of recent technologies and their availability to all.

Effect of Tai Chi on muscle strength, physical endurance, postural balance and flexibility: a systematic review and meta-analysis.

OBJECTIVE: To investigate the impact of Tai Chi training on muscle strength, physical endurance, postural balance and flexibility, as measured by tests commonly used in health-related fitness or competitive sports contexts. DESIGN: Systematic review and meta-analysis. DATA SOURCES: The following databases were searched up to 31 July 2020: CINAHL, Cochrane Library, MEDLINE via PubMed and SPORTDiscus. ELIGIBILITY CRITERIA FOR STUDIES: Inclusion: (1) Randomised controlled trials published in German or English; (2) Tai Chi used as an intervention to improve physical performance; (3) Test methods commonly used in health-related fitness or competitive sports and (4) Participants aged ≥16 years (irrespective of health status). Exclusion: (1) Studies not focusing on Tai Chi or including Tai Chi mixed with other interventions and (2) Modified or less than eight Tai Chi movements. RESULTS: Out of 3817 records, 31 studies were included in the review, 21 of them in the meta-analysis. Significant improvements in handgrip strength (2.34 kg, 95% CI 1.53 to 3.14), walking distance during 6 min (43.37 m, 95% CI 29.12 to 57.63), standing time in single-leg-stance with open eyes (6.41 s, 95% CI 4.58 to 8.24) and thoracolumbar spine flexibility (2.33 cm, 95% CI 0.11 to 4.55) were observed. CONCLUSION: Tai Chi training seems to moderately improve physical fitness when evaluated by tests used in health-related fitness or competitive sports. Moreover, thoracolumbar spine flexibility seems to be a factor in the improvement of postural balance. Further research is needed, including younger healthy participants performing a widely used, standardised form (eg, Peking-style routine) with high-intensity movements (eg, use of lower stances).