The Tokyo 2020 Olympics and Paralympic Games were held in the hottest environment in the history of the games. Additionally, the worldwide coronavirus disease 2019 (COVID-19) pandemic necessitated daily polymerase chain reaction (PCR) testing during the games, wearing a mask became mandatory publicly, and it was an unheard and unique Olympic with no spectators. Heat acclimation, hydration, and body cooling are essential for safe and high-performance activities in hot environments. In 2015, the Japan Institute of Sports Sciences launched the \"Heat Countermeasure Project\" to conduct experiments and practical research on heat countermeasures and investigate issues related to heat countermeasures in each athletic event. The results obtained were proposed to various Japan national sports teams, and support for heat countermeasures for the Tokyo 2020 games was promoted in consultation with national federations. Furthermore, due to the COVID-19 pandemic, infectious disease countermeasures for the Tokyo 2020 Games during support were a must. Moreover, athletes, coaches, and team staff could not avoid implementing heat countermeasures while adopting measures against infectious diseases. This study aimed to clarify the issues faced with heat countermeasures and report on heat acclimation training and cooling support efforts, considering measures against infectious diseases.

OBJECTIVE: Multi-ligament knee injuries (MLKI) can be debilitating and often career ending injuries for athletes. Current literature reports on outcomes following these injuries for return to activities of daily life; however, there is a paucity of evidence evaluating the return to sport following a MLKI. The purpose of this case report is to describe the treatment and outcome following a MLKI and novel meniscus radial repair technique in which the athlete returned to compete in the 2018 Winter Olympic Games 14 months postoperatively.
METHODS: Case Report.
METHODS: A healthy 28-year-old female Olympic alpine skier who sustained a deep knee flexion with varus force injury to her right knee during a competitive skiing event. Examination and imaging revealed a completely torn anterior cruciate ligament (ACL) and lateral collateral ligament (LCL), complex radial tear of the lateral meniscus, medial meniscus tear, popliteofibular ligament tear, proximal tibiofibular joint ligament tear, and a common peroneal nerve neuropraxia. The athlete underwent an anatomic single-stage, multi-ligament knee reconstruction surgery which consisted of a novel meniscus radial repair technique.
RESULTS: A return to snow progression was initiated at seven months postoperatively. At 10 months postoperatively, a physical exam revealed trace effusion, no joint line tenderness, and negative stability tests. A repeat MRI revealed adequate healing of the lateral meniscus radial repair. The athlete passed a functional sports test at 10-months postoperatively and was cleared to return to ski with no restrictions. At 12 months postoperatively, the athlete placed in an Olympic qualifying ski race. At 14 months postoperatively, the athlete competed in the 2018 Olympic Winter Games.
CONCLUSIONS: This case report highlights the ability of an athlete to return to elite level of competition following an anatomic single-stage, multi-ligament knee reconstruction with a novel meniscus radial repair in a safe but timely manner.
METHODS: 4.

This study was carried out to characterize three aldehydes of health concern (formaldehyde, acetaldehyde, and acrolein) at a central Beijing site in the summer and early fall of 2008 (from June to October). Aldehydes in polluted atmospheres come from both primary and secondary sources, which limits the control strategies for these reactive compounds. Measurements were made before, during, and after the Beijing Olympics to examine whether the dramatic air pollution control measures implemented during the Olympics had an impact on concentrations of the three aldehydes and their underlying primary and secondary sources. Average concentrations of formaldehyde, acetaldehyde and acrolein were 29.3±15.1 μg/m3, 27.1±15.7 μg/m3 and 2.3±1.0 μg/m3, respectively, for the entire period of measurements, all being at the high end of concentration ranges measured in cities around the world in photochemical smog seasons. Formaldehyde and acrolein increased during the pollution control period compared to the pre-Olympic Games, followed the changing pattern of temperature, and were significantly correlated with ozone and with a secondary formation factor identified by principal component analysis (PCA). In contrast, acetaldehyde had a reduction in mean concentration during the Olympic air pollution control period compared to the pre-Olympic period and was significantly correlated with several pollutants emitted from local emission sources (e.g., NO2, CO, and PM2.5). Acetaldehyde was also more strongly associated with primary emission sources including vegetative burning and oil combustion factors identified through the PCA. All three aldehydes were lower during the post-Olympic sampling period compared to the before and during Olympic periods, likely due to seasonal and regional effects. Our findings point to the complexity of source control strategies for secondary pollutants.

This paper examines the politics of mobility which surrounded the London 2012 Olympics. We provide a critical discussion of the mobility conflicts, problems and criticisms which emerged from our research with local people in the Stratford and wider Newham areas of London, where most Olympic events were located. The paper is divided into four broad parts. First, we identify and discuss the relevant components of the \'mobilities paradigm\' in social science which underpin our analysis. Second, we briefly outline our research methods, centring particularly on fieldwork and interviews with different social groups. Third, we examine in detail the six main themes of mobility politics which were evident at London 2012, relating to social context, event construction, event mobility systems, commercial mobilities, the mobile politics of exclusion, and contested modes of mobility. In doing so, we seek to extend the mobilities paradigm by introducing various concepts and keywords - notably on the three-speed city, entryability, mobility panics, instrumental mobility, and corporate kettling - which may be utilized by social scientists to examine mobility systems in other social contexts. We conclude by reaffirming the significance of mobility-focused research at sport and other mega-events, and by indicating future lines of inquiry for social scientists.