Coronavirus disease-2019: A tocsin to our aging,unfit, corpulent,and immunodeficient society

Acute and chronic respiratory illnesses cause widespread morbidity and mortality, and this class of illness now includes the novel coronavirus severe acute respiratory syndrome that is causing coronavirus disease-2019 (COVID-19). The world is experiencing a major demographic shift toward an older, obese, and physically inactive populace. Risk factor assessments based on pandemic data indicate that those at higher risk for severe illness from COVID-19 include older males, and people of all ages with obesity and related comorbidities such as hypertension and type 2 diabetes. Aging in and of itself leads to negative changes in innate and adaptive immunity, a process termed immunosenescence. Obesity causes systemic inflammation and adversely impacts immune function and host defense in a way that patterns immunosenescence. Two primary prevention strategies to reduce the risk for COVID-19 at both the community and individual levels include mitigation activities and the adoption of lifestyle practices consistent with good immune health. Animal and human studies support the idea that, in contrast to high exercise workloads, regular moderate-intensity physical activity improves immunosurveillance against pathogens and reduces morbidity and mortality from viral infection and respiratory illnesses including the common cold, pneumonia, and influenza. The odds are high that infectious disease pandemics spawned by novel pathogens will continue to inflict morbidity and mortality as the world's population becomes older and more obese. COVID-19 is indeed a wake-up call, a tocsin, to the world that primary prevention countermeasures focused on health behaviors and hygiene demand our full attention and support.     

Physical activity lowers the risk for acute respiratory infections: Time for recognition

Physical inactivity is a well-established risk factor for chronic diseases, such as cardiovascular disease, cancer, and diabetes mellitus. There is a growing awareness that physical inactivity should also be regarded as a risk factor for acute respiratory infections (ARIs). ARIs, such as the common cold, influenza, pneumonia, and coronavirus disease 2019 (COVID-19), are among the most pervasive diseases on earth and cause widespread morbidity and mortality. Evidence in support of the linkage between ARIs and physical inactivity has been strengthened during the COVID-19 pandemic because of increased scientific scrutiny. Large-scale studies have consistently reported that the risk for severe COVID-19 outcomes is elevated in cohorts with low physical activity and/or physical fitness, even after adjusting for other risk factors. The lowered risk for severe COVID-19 and other ARIs in physically active groups is attributed to exercise-induced immunoprotective effects, including enhanced surveillance of key immune cells and reduced chronic inflammation. Scientific consensus groups, including those who submitted the Physical Activity Guidelines for Americans, have not yet given this area of research the respect that is due. It is time to add “reduced risk for ARIs” to the “Exercise is Medicine” list of physical activity-related health benefits.     

Physical activity and nutrition guidelines to help with the fight against COVID-19

ABSTRACT

As the world is witnessing the epidemic of coronavirus disease 2019, emerging genetics and clinical pieces of evidence suggest a similar immunopathology to those of severe acute respiratory syndrome and Middle East respiratory syndrome. Staying at home to prevent the spread of the virus and consequently being largely inactive is associated with unintended consequences. These can actually enhance the infection risk and exacerbate poor health conditions including impaired immune function. Physical activity is a feasible way of improving health, particularly physical and mental health in a time of social isolation. However, people with certain health conditions in these circumstances may need a special physical activity programme in addition to any exercise they may already be performing via online programmes. This review aims to provide practical guidelines during the COVID-19 quarantine period. We suggest performing aerobic, resistance training, respiratory muscle training and yoga in the healthy, and in those with upper respiratory tract illness, patients with lower respiratory tract illness should be restricted to respiratory muscle training and yoga. In addition, vitamins D and C, omega-3 fatty acids, and regular consumption of fruit and vegetables might be considered as nutritional aids to support the immune system in those affected by COVID-19.     

太极拳对老年人身心健康影响的研究进展

大量研究表明老年人更易患新型冠状病毒肺炎(COVID-19)在内的呼吸道传染病,新型冠状病毒的爆发对老年人的心理和生理都造成了严重的损害。太极拳刚柔并济,具有独特的呼吸和动作节奏,对老年人的心理、生理健康都有积极的促进作用,相关研究分散于文献中。文章总结分析了太极拳对老年人心理、生理健康的影响及其机制并提供了相应的太极拳练习方式以供老年人练习时参考,为疫情常态化防控状态下老年人的健康促进提供借鉴。     

Projecting the impact of the coronavirus disease-2019 pandemic on childhood obesity in the United States: A microsimulation model

PurposeThe coronavirus disease-2019 (COVID-19) pandemic in the United States led to nationwide stay-at-home orders and school closures. Declines in energy expenditure resulting from canceled physical education classes and reduced physical activity may elevate childhood obesity risk. This study estimated the impact of COVID-19 on childhood obesity.MethodsA microsimulation model simulated the trajectory of a nationally representative kindergarten cohort's body mass index z-scores and childhood obesity prevalence from April 2020 to March 2021 under the control scenario without COVID-19 and under the 4 alternative scenarios with COVID-19—Scenario 1: 2-month nationwide school closure in April and May 2020; Scenario 2: Scenario 1 followed by a 10% reduction in daily physical activity in the summer from June to August; Scenario 3: Scenario 2 followed by 2-month school closure in September and October; and Scenario 4: Scenario 3 followed by an additional 2-month school closure in November and December.ResultsRelative to the control scenario without COVID-19, Scenarios 1, 2, 3, and 4 were associated with an increase in the mean body mass index z-scores by 0.056 (95% confidence interval (95%CI): 0.055–0.056), 0.084 (95%CI: 0.084–0.085), 0.141 (95%CI: 0.140–0.142), and 0.198 (95%CI: 0.197–0.199), respectively, and an increase in childhood obesity prevalence by 0.640 (95%CI: 0.515–0.765), 0.972 (95%CI: 0.819–1.126), 1.676 (95%CI: 1.475–1.877), and 2.373 (95%CI: 2.135–2.612) percentage points, respectively. Compared to girls and non-Hispanic whites and Asians, the impact of COVID-19 on childhood obesity was modestly larger among boys and non-Hispanic blacks and Hispanics, respectively.ConclusionPublic health interventions are urgently called to promote an active lifestyle and engagement in physical activity among children to mitigate the adverse impact of COVID-19 on unhealthy weight gains and childhood obesity.     

Physical activity and its relationship with COVID-19 cases and deaths: Analysis of U.S. counties

PurposeThe study was to examine county-level associations of physical activity with coronavirus disease 2019 (COVID-19) cases and deaths, per 100,000 county residents.MethodsData were collected from publicly available data sources for 3142 counties and equivalents, including the District of Columbia. Subjective health ratings, percentage uninsured, percentage unemployed, median household income, percentage female residents, percentage White residents, percentage of residents 65 years of age or older, and rural designation served as controls.ResultsThe two-level random intercept regression showed that physical activity rates at the county level were statistically and negatively associated with COVID-19 cases and deaths. Additional analyses showed that physical activity rates moderated the relationship between cases and deaths, such that the relationship was strongest when physical activity rates were low.ConclusionThe results presented here offer empirical evidence of the benefits of county-level physical activity during a pandemic. Implications for public health and physical activity provision are discussed.     

Physical fitness before and during the COVID-19 pandemic: Results of annual national physical fitness surveillance among 16,647,699 Japanese children and adolescents between 2013 and 2021

BackgroundLimited nationally representative evidence is available on temporal trends in physical fitness (PF) for children and adolescents during the coronavirus disease 2019 (COVID-19) pandemic. The primary aim was to examine the temporal trends in PF for Japanese children and adolescents before and during the COVID-19 pandemic. The secondary aim was to estimate the concurrent trends in body size (measured as body mass and height) and movement behaviors (exercise, screen, and sleep time).MethodsCensus PF data for children in Grade 5 (aged 10–11 years) and adolescents in Grade 8 (aged 13–14 years) were obtained for the years 2013–2021 from the National Survey of Physical Fitness, Athletic Performance, and Exercise Habits in Japan (n = 16,647,699). PF and body size were objectively measured, and movement behaviors were self-reported. Using sample-weighted linear regression, temporal trends in mean PF were calculated before the pandemic (2013–2019) and during the pandemic (2019–2021) with adjustments for age, sex, body size, and exercise time.ResultsWhen adjusted for age, sex, body size, and exercise time, there were significant declines in PF during the pandemic, with the largest declines observed in 20-m shuttle run (standardized (Cohen's) effect size (ES) = −0.109 per annum (p.a.)) and sit-ups performance (ES = −0.133 p.a.). The magnitude of the declines in 20-m shuttle run and sit-ups performances were 18- and 15-fold larger, respectively, than the improvements seen before the pandemic (2013–2019), after adjusting for age, sex, body size, and exercise time. During the pandemic, both body mass and screen time significantly increased, and exercise time decreased.ConclusionDeclines in 20-m shuttle run and sit-ups performances suggest corresponding declines in population health during the COVID-19 pandemic.     

Exploring the impact of COVID-19 on the movement behaviors of children and youth: A scoping review of evidence after the first year

PurposeThe objective of this scoping review was to summarize systematically the available literature investigating the relationships between the coronavirus disease 2019 (COVID-19) pandemic and movement behaviors (physical activity, sedentary behavior, and sleep) of school-aged children (aged 5−11 years) and youth (aged 12−17 years) in the first year of the COVID-19 outbreak.MethodsSearches for published literature were conducted across 6 databases on 2 separate search dates (November 25, 2020, and January 27, 2021). Results were screened and extracted by 2 reviewers (DCP and KR) independently, using Covidence. Basic numeric analysis and content analysis were undertaken to present thematically the findings of included studies according to the associated impact on each movement behavior.ResultsA total of 1486 records were extracted from database searches; of those, 150 met inclusion criteria and were included for analysis. Of 150 articles, 110 were empirical studies examining physical activity (n = 77), sedentary behavior/screen time (n = 58), and sleep (n = 55). Results consistently reported declines in physical-activity time, increases in screen time and total sedentary behavior, shifts to later bed and wake times, and increases in sleep duration. The reported impacts on movement behaviors were greater for youth than for children.ConclusionThe COVID-19 pandemic is related to changes in the quantity and nature of physical activity, sedentary behavior, and sleep among children and youth. There is an urgent need for policy makers, practitioners, and researchers to develop solutions for attenuating adverse changes in physical activity and screen time among children and youth.     

Canadian children's and youth's adherence to the 24-h movement guidelines during the COVID-19 pandemic: A decision tree analysis

PurposeThe purpose of this study was to use decision tree modeling to generate profiles of children and youth who were more and less likely to meet the Canadian 24-h movement guidelines during the coronavirus disease-2019 (COVID-19) outbreak.MethodsData for this study were from a nationally representative sample of 1472 Canadian parents (Mean_age = 45.12, SD = 7.55) of children (5–11 years old) or youth (12–17 years old). Data were collected in April 2020 via an online survey. Survey items assessed demographic, behavioral, social, micro-environmental, and macro-environmental characteristics. Four decision trees of adherence and non-adherence to all movement recommendations combined and each individual movement recommendation (physical activity (PA), screen time, and sleep) were generated.ResultsResults revealed specific combinations of adherence and non-adherence characteristics. Characteristics associated with adherence to the recommendation(s) included high parental perceived capability to restrict screen time, annual household income of ≥ CAD 100,000, increases in children's and youth's outdoor PA/sport since the COVID-19 outbreak began, being a boy, having parents younger than 43 years old, and small increases in children's and youth's sleep duration since the COVID-19 outbreak began. Characteristics associated with non-adherence to the recommendation(s) included low parental perceived capability to restrict screen time, youth aged 12–17 years, decreases in children's and youth's outdoor PA/sport since the COVID-19 outbreak began, primary residences located in all provinces except Quebec, low parental perceived capability to support children's and youth's sleep and PA, and annual household income of ≤ CAD 99,999.ConclusionOur results show that specific characteristics interact to contribute to (non)adherence to the movement behavior recommendations. Results highlight the importance of targeting parents’ perceived capability for the promotion of children's and youth's movement behaviors during challenging times of the COVID-19 pandemic, paying particular attention to enhancing parental perceived capability to restrict screen time.     

No independent associations between physical activity and clinical outcomes among hospitalized patients with moderate to severe COVID-19

BackgroundRegular physical activity (PA) has been postulated to improve, or at least maintain, immunity across the life span. However, the link between physical (in)activity and coronavirus disease 2019 (COVID-19) remains to be established. This small-scale prospective cohort study is nested within a randomized controlled trial aimed to investigate the possible associations between PA levels and clinical outcomes among hospitalized patients with moderate to severe COVID-19.MethodsHospitalized patients with COVID-19 (mean age: 54.9 years) were recruited from the Clinical Hospital of the School of Medicine of the University of Sao Paulo (a quaternary referral teaching hospital) and from Ibirapuera Field Hospital, both located in Sao Paulo, Brazil. PA level was assessed using the Baecke Questionnaire of Habitual Physical Activity. The primary outcome was hospital length of stay. The secondary outcomes were mortality, admission to the intensive care unit (ICU), and mechanical ventilation requirement.ResultsThe median hospital length of stay was 7.0 ± 4.0 days, median ± IQR; 3.3% of patients died, 13.8% were admitted to the ICU, and 8.6% required mechanical ventilation. Adjusted linear regression models showed that PA indices were not associated with hospital length of stay (work index: β = –0.57 (95% confidence interval (95%CI): –1.80 to 0.65), p = 0.355; sport index: β = 0.43 (95%CI: –0.94 to 1.80), p = 0.536; leisure-time index: β = 1.18 (95%CI: –0.22 to 2.59), p = 0.099; and total activity index: β = 0.20 (95%CI: –0.48 to 0.87), p = 0.563). None of the PA indices were associated with mortality, admission to the ICU, or mechanical ventilation requirement (all p > 0.050).ConclusionAmong hospitalized patients with COVID-19, PA did not independently associate with hospital length of stay or any other clinically relevant outcomes. These findings should be interpreted as meaning that, among already hospitalized patients with more severe forms of COVID-19, being active is a potential protective factor likely outweighed by a cluster of comorbidities (e.g., type 2 diabetes, hypertension, weight excess) and older age, suggesting that the benefit of PA against the worsening of COVID-19 may vary across stages of the disease.     

The impact of the coronavirus disease 2019 pandemic on physical activity in U.S. children

BackgroundDaily moderate-to-vigorous physical activity (MVPA) is vital to the physical, mental, and social well-being of children. Early restrictions during the coronavirus disease 2019 (COVID-19) pandemic included the closure of schools and physical activity (PA) amenities across the US. This study aimed to examine the impact of the pandemic on the PA and play behavior of U.S. children and to provide evidence-based recommendations to improve their PA.MethodsA cross-sectional, online, parent-reported survey was conducted of children aged 3–18 years between April and June 2020 to assess light PA and MVPA using a modified Godin Leisure-Time Exercise Questionnaire. Additional items included family/child socioeconomic demographics, child adaptability to the pandemic, and community access. The survey was shared through social media and snowball sampling distribution.ResultsAnalysis of 1310 surveys indicated child PA scores declined significantly during the pandemic (from 56.6 to 44.6, max 119, p < 0.001). Specifically, MVPA score decreased (from 46.7 to 34.7, max 98, p < 0.001) while light PA remained the same. Age-based changes were seen in the quantity, variety, and intensity of PA, with the lowest pandemic-related impact seen in preschoolers and the highest in high schoolers (–4.7 vs. –17.2, p < 0.001). Community-based peer PA decreased across all age groups.ConclusionThis study shows decreased PA levels in U.S. children, according to parent reporting, during the COVID-19 pandemic. Recommendations for community leaders, educators, and parents to improve PA in children are provided. With continued spread of COVID-19, these results and recommendations may be imperative to the physical well-being of U.S. children.     

Back to school after lockdown: The effect of COVID-19 restrictions on children's device-based physical activity metrics

BackgroundThe coronavirus disease-2019 (COVID-19) pandemic and national lockdowns took away opportunities for children to be physically active. This study aimed to determine the effect of the COVID-19 lockdown on accelerometer-assessed physical activity (PA) in children in Wales.MethodsEight hundred participants (8–18 years old), stratified by sex, age, and socio-economic status, wore Axivity AX3 accelerometers for 7 days in February 2021, during the lockdown, and in May 2021, while in school. Raw accelerometer data were processed in R-package GGIR, and cut-point data, average acceleration (AvAcc), intensity gradient, and the acceleration above which the most active X minutes are accumulated (MX) metrics were extracted. Linear mixed models were used to assess the influence of time-point, sex, age, and socioeconomic status (SES) on PA.ResultsDuring lockdown, moderate-to-vigorous PA was 38.4 ± 24.3 min/day; sedentary time was 849.4 ± 196.6 min/day; mean ± SD. PA levels increased significantly upon return to school (all variables p < 0.001). While there were no sex differences during lockdown (p = 0.233), girls engaged in significantly less moderate-to-vigorous PA than boys once back in school (p < 0.001). Furthermore, boys had more favorable intensity profiles than girls (intensity gradient: p < 0.001), regardless of time-point. PA levels decreased with age at both time-points; upper secondary school girls were the least active group, with an average M30 of 195.2 mg (while in school).ConclusionThe lockdown affected boys more than girls, as reflected by the disappearance of the typical sex difference in PA levels during lockdown, although these were re-established on return to school. Upper secondary school (especially girls) might need specific COVID-recovery intervention.     

Effects of a remote,YouTube-delivered exercise intervention on young adults’physical activity,sedentary behavior,and sleep during the COVID-19 pandemic:Randomized controlled trial

Background:Public health guidelines have called for innovative and flexible physical activity(PA)intervention strategies to promote PA and health amid the coronavirus disease 2019(COVID-19)pandemic.Therefore,this study’s purpose was to examine the effects of a home-based,YouTube-delivered PA intervention grounded in self-determination theory on young adults’free-living PA,sedentary behavior,and sleep quality(NCT04499547).Methods:Sixty-four young adults(48 females;age=22.8±3.4 years,mean±SD;body mass index=23.1±2.6 kg/m²)were randomized(1:1)into the intervention group,which received weekly aerobic and muscle-strengthening PA videos,or control group,which received weekly general health education videos,for 12 weeks.Our primary outcome was free-living moderate-to-vigorous PA(MVPA)and our secondary outcomes were sedentary behavior,light PA,and sleep quality(measured using ActiGraph accelerometers)along with muscle-strengthening PA frequency,self-determination theory-related motivation(non-regulation,external regulation,introjected regulation,identified regulation,integrated regulation,and intrinsic regulation),and perceived PA barriers(assessed using validated questionnaires).Repeated measures analysis of variances(ANOVAs)examined between-group differences at an adjusted significance level of 0.004 and effect sizes as partial eta-squared(η;).Results:We observed statistically significant interaction effects for MVPA,sleep efficiency,muscle-strengthening PA frequency,non-regulation,integrated regulation,intrinsic regulation,and perceived PA barriers(F(1,62)=10.75-77.67,p<0.001-0.002,η_p²=0.15-0.56)with all outcomes favoring the intervention group.We observed no statistically significant differences in either group for sedentary behavior,light PA,sleep duration,or external,introjected,and identified regulations after 12 weeks(F(1,62)=1.11-3.64,p=0.06-0.61).Conclusion:With national COVID-19 restrictions still in place and uncertainty regarding post-pandemic PA environments and behaviors,a remote,YouTube-delivered PA intervention may help foster clinically meaningful improvements in young adults’free-living MVPA,musclestrengthening PA frequency,sleep efficiency,PA-related intrinsic motivation,and perceived PA barriers.     

运动员感染新冠病毒后恢复训练的研究综述

运动员感染新型冠状病毒会对身体机能与运动能力产生明显的影响。在新毒株仍然流行于世界范围内的背景下,如何帮助运动员安全、快速地恢复训练是当前竞技体育面临的实践需求。通过总结新冠病毒感染对运动能力、心理和营养状况的影响,归纳恢复训练的原则和如何分期训练,首次提出针对我国运动员在康复后进行评估、科学监控及心理和营养干预的措施,为体育工作者制定与实施恢复训练计划提供参考,力图以此为起点推进我国运动员感染新冠病毒后恢复训练的进一步科学研究。     

Recovery shape of physical activity after COVID-19 pandemic

BackgroundSince the shutdowns associated with the coronavirus disease 2019 pandemic, there has been limited discourse on physical activity (PA) recovery (i.e., the ability of individuals to resume PA at pre-pandemic levels), including recovery rate, speed of recovery, which individuals are able to return quickly, who is left behind, and what are the causes of those differences. This study aimed to estimate the level and shape of PA recovery rate in Thailand.MethodsThis study employed 2 rounds (2020 and 2021) of Thailand's Surveillance on Physical Activity dataset for the analysis. Each round included over 6600 samples from individuals aged 18 years or older. PA was assessed subjectively. Recovery rate was calculated from the relative difference in the cumulative minutes of moderate-to-vigorous PA (MVPA) from 2 different periods.ResultsThe Thai population experienced a medium level of recession of PA (−26.1%) and a moderate level of recovery of PA (37.44%). PA recovery in the Thai population resembled an imperfect V shape, reflecting a sharp decline followed by an immediate upturn; still, recovered PA remained lower than pre-pandemic levels. The quickest recovery was found among older adults, whereas students, young adults, residents of Bangkok, the unemployed, and those who had a negative attitude toward PA experienced the highest recession of PA and were among the slowest to recover.ConclusionThe level of recovery of PA among Thai adults is largely determined by the preventive behaviors demonstrated by groups within the population who have a higher awareness of their health. The effect of the mandatory coronavirus disease 2019 containment measures on PA was temporary. However, the slower recovery rate of PA among some individuals was caused by a combination of restrictive measures and socioeconomic inequality, which required more time and effort to overcome.     

新冠疫情背景下体育特色小镇的治理及发展策略研究

2020年初新型冠状病毒肺炎疫情在全世界迅速蔓延,对我国的体育发展造成了严重的影响,体育特色小镇的发展在本次新冠疫情中也遭遇重创。在新冠疫情的背景下对体育特色小镇的治理及发展策略进行研究,并针对存在的问题提出相应对策,旨在为我国体育特色小镇的持续发展提供参考。     

运动对疫苗免疫应答影响的研究进展

对近20年来国内外有关运动干预影响疫苗接种后免疫应答的效应、机制进行系统分析,结果发现:在疫苗接种前或疫苗接种后进行急、慢性运动干预,可促进机体免疫系统对疫苗产生更好免疫应答反应,使疫苗接种后的抗体滴度水平更高,提升速度更快,且对宿主的免疫保护作用更持久,尤其是在年老、体弱、多病和女性人群中效果更明显,同时还可减轻疫苗接种后产生的不良反应,其机制与运动能够加快血液循环、增加循环血液中的白细胞数量、改变组织中细胞因子或趋化因子含量和淋巴循环,以及运动引起肌纤维微细损伤造成的炎性环境有关。研究结论对当前全球人口正在进行的新冠肺炎疫苗接种具有启示性意义。     

急性运动降低感染风险的免疫调节机制

由于新型冠状病毒(2019-nCoV)感染的肺炎疫情暴发,人们将居家运动作为提高免疫力与保持健康的重要手段,运动与免疫的关系再度受到关注。一般认为,在充分恢复的前提下进行规律的中高强度运动可提高免疫功能,而急性运动(acute exercise)可能抑制免疫功能并增加感染风险。急性运动后外周血淋巴细胞计数及功能降低、免疫球蛋白A水平分泌减少被认为是运动抑制免疫的理论基础。但目前这种独立于非运动因素影响免疫功能增加感染风险的认识受到了现有研究的挑战。急性运动可通过应激反应将淋巴细胞亚群迅速动员至循环中,运动结束后,淋巴细胞亚群又会迅速迁移至外周组织。淋巴细胞的重新分布(lymphocyte redeployment)可能是一种进化保守的免疫机制,这一过程强化了外周组织的免疫监视与调节功能,有助于提升机体抵抗感染能力。因此,从这一视角就急性运动对机会性感染风险及免疫功能影响的现状进行综述。     

加拿大孕期体力活动指南（2019）解读与启示

运用文献资料法、逻辑分析法等对加拿大孕期体力活动指南（2019）研制背景、方法和内容等进行分析，探究其特点和规律。主要结论：（1）孕期体力活动指南是目前该研究领域研究成果的继承和完善，重视不同类型体力活动与健康相关证据的收集，依据专家组共识、文献分析、体力活动与健康的剂量-效应关系，并通过公共意见咨询，确保指标制定过程的科学性、严谨性、适用性；（2）采用质量控制方法研制孕期体力活动指南，为受众群体提供合理化的体力活动强度、活动方式及活动安全防控等内容。建议：在“健康中国2030”目标引领下，应尽快研制我国孕期体力活动指南，为孕期体力活动提供科学依据，构建体医融合的服务模式     

东京奥运会延期举办背景下东道主形象修复策略研究

新冠疫情对东京奥运会各项筹办工作和东道主形象产生了负面的影响,日本方面因时而变、因势利导,积极引导国际舆论走向,维护奥运会东道主的良好形象。东京奥运会延期举办事件的决策过程经历了4个发展阶段,对东京奥运会延期举办背景下各方定义的新闻议程进行了分析,结合新闻议程内容对奥运会东道主形象修复策略展开了研究。日本方面根据全球疫情变化、本国疫情防控形势和国际舆论走向,针对不同的发展阶段,采取了建立信心、推卸责任、拖延、诚意等形象修复策略,试图强化人们对于东京奥运会东道主安全条件的形象认知,致力于维护日本“安全之手”的国际形象,增强世界各国对于东京奥运会顺利举办的信心,在危机应对中实现国家利益最大化,其中不乏成功经验值得借鉴参考。