Is exercise protective against influenza-associated mortality?

Habitual physical activity and COVID-19

BACKGROUND

Physical activity (PA) is known to decrease COVID-19 risk factors and can attenuate symptoms of viral infections. However, difficulty exercising and fatigue are common complaints after COVID-19. It is unknown whether prior habitual PA will improve outcomes and what the time course is until full recovery of PA after COVID-19.

METHODS

Invitations were emailed to 21,933 adults who were SARS-CoV-2 positive between March 2020 and February 2021. Participants completed intake surveys and the Physical Activity History (PAH) questionnaire regarding PA during the 3-month prior to infection. Monthly thereafter, for up to 23 months, participants were emailed surveys. Scores were computed for moderate and heavy PA. Long COVID (LC) was defined as having recurring/persistent symptoms 9 months after diagnosis.

RESULTS

Overall, 993 patients completed the intake survey (age 50.7±15.8 years, BMI 27.3±9.2, 58% women); 28% had been hospitalized. One-third had recovered to their pre-infection level of PA at 9 months post-infection; this increased to 65% at one year, and 90% at two years. Higher pre-diagnosis PA reduced odds of hospitalization (P<0.05) but not of LC. Factors predictive of poor PA recovery were higher pre-diagnosis PA, shortness of breath and fatigue during acute illness, and fatigue chronically. Participants who reported ongoing symptoms had consistently poorer recovery of habitual PA compared to those not reporting chronic symptoms.

CONCLUSIONS

Habitual PA reduced odds of hospitalization but not of LC. Thirty-five percent had not returned to pre-COVID-19 levels of PA one year after infection, representing a major public health threat.

Leisure-time physical activity and mortality from influenza and pneumonia: a cohort study of 577 909 US adults

OBJECTIVE

To examine the association of leisure-time physical activity with mortality from influenza and pneumonia.

METHODS

A nationally representative sample of US adults (aged ≥18 years) who participated in the National Health Interview Survey from 1998 to 2018 were followed for mortality through 2019. Participants were classified as meeting both physical activity guidelines if they reported ≥150 min/week of moderate-intensity equivalent aerobic physical activity and ≥2 episodes/week of muscle-strengthening activity. Participants were also classified into five volume-based categories of self-reported aerobic and muscle-strengthening activity. Influenza and pneumonia mortality was defined as having an underlying cause of death with an International Classification of Diseases, 10th Revision code of J09-J18 recorded in the National Death Index. Mortality risk was assessed using Cox proportional hazards, adjusting for sociodemographic and lifestyle factors, health conditions and influenza and pneumococcal vaccination status. Data were analysed in 2022.

RESULTS

Among 577 909 participants followed for a median of 9.23 years, 1516 influenza and pneumonia deaths were recorded. Compared with participants meeting neither guideline, those meeting both guidelines had 48% lower adjusted risk of influenza and pneumonia mortality. Relative to no aerobic activity, 10-149, 150-300, 301-600 and >600 min/week were associated with lower risk (by 21%, 41%, 50% and 41%). Relative to <2 episodes/week of muscle-strengthening activity, 2 episodes/week was associated with 47% lower risk and ≥7 episodes/week with 41% higher risk.

CONCLUSIONS

Aerobic physical activity, even at quantities below the recommended level, may be associated with lower influenza and pneumonia mortality while muscle-strengthening activity demonstrated a J-shaped relationship.

Fatigue and Physical Activity in People after COVID-19 in Poland

OBJECTIVES

The purpose of this research was to look at the amount of fatigue and physical activity (PA) in individuals after COVID-19 in Poland and the correlation between fatigue and PA.

METHODS

The online research was carried out among adult Polish residents (122 women and 82 men) who had tested positive for SARS-CoV-2 during the previous year. The level of fatigue was measured using the Modified Fatigue Impact Scale (MFIS). The PA level was assessed using the International Physical Activity Questionnaire (IPAQ).

RESULTS

A total of 46.6% of the subjects had been ill with COVID-19 for more than 6 months before the time of the survey response. The MFIS total measure is 77 of the maximum score, and the median is 17. A total of 26% of respondents reported low activity, while 41% of respondents reported high activity. A statistically significant negative relationship was found between PA level and total fatigue score. The best scores for fatigue and PA were obtained by the subjects with mild COVID-19. The time since diagnosis (as opposed to older age and female sex) was not clearly associated with most measures.

CONCLUSIONS

PA may play an important role in regulating the severity of fatigue; it should be increased, especially in patients after COVID. Further studies are also needed to investigate the mechanism of differences in fatigue and PA.

Coping with the COVID-19 pandemic by strengthening immunity as a nonpharmaceutical intervention: A major public health challenge

Background and Aims

The global Coronavirus-2 outbreak has emerged as a significant threat to majority of individuals around the world. The most effective solution for addressing this viral outbreak is through vaccination. Simultaneously, the virus's mutation capabilities pose a potential risk to the effectiveness of both vaccines and, in certain instances, newly developed drugs. Conversely, the human body's immune system exhibits a robust ability to combat viral outbreaks with substantial confidence, as evidenced by the ratio of fatalities to affected individuals worldwide. Hence, an alternative strategy to mitigate this pandemic could involve enhancing the immune system's resilience.

Methods

The research objective of the review is to acquire a comprehensive understanding of the role of inflammation and immunity in COVID-19. The pertinent literature concerning immune system functions, the impact of inflammation against viruses like SARS-CoV-2, and the connection between nutritional interventions, inflammation, and immunity was systematically explored.

Results

Enhancing immune function involves mitigating the impact of key factors that negatively influence the immune response. Strengthening the immune system against emerging diseases can be achieved through nonpharmaceutical measures such as maintaining a balanced nutrition, engaging in regular exercise, ensuring adequate sleep, and managing stress.

Conclusion

This review aims to convey the significance of and provide recommendations for immune-strengthening strategies amidst the ongoing COVID-19 pandemic.

Exercise is the Most Important Medicine for COVID-19

ABSTRACT

COVID-19 infection and long COVID affect multiple organ systems, including the respiratory, cardiovascular, renal, digestive, neuroendocrine, musculoskeletal systems, and sensory organs. Exerkines, released during exercise, have a potent crosstalk effect between multiple body systems. This review describes the evidence of how exerkines can mitigate the effects of COVID-19 in each organ system that the virus affects. The evidence presented in the review suggests that exercise should be considered a first-line strategy in the prevention and treatment of COVID-19 infection and long COVID disease.

Exercise and COVID-19: exercise intensity reassures immunological benefits of post-COVID-19 condition

Any form of physical activity, including exercise, has various benefits at the physiological (improving cardiac and respiratory functions, increasing skeletal muscle mass, and maintaining homeostasis) and psychological levels (improving cognitive function, reducing anxiety and depression) which help to combat any type of infection. In contrast, the infectivity ratio could reduce the physical activity of an individual, such as performing a habitual exercise. Adaptation to different exercise strategies including intensity and duration may better increase physical performance and improve the symptoms. For example, low to moderate intensity perhaps fails to induce this adaptive process, while high-intensity of exercise compromises immune health. This can aggravate the infection rate (Open window theory). However, high intensity with a shorter time produces various morphological alterations in the primary organs including the lungs and heart, which facilitate life support in COVID-19 patients. However, less information about exercise protocols failed to assure the benefits of exercise to COVID-19 patients, particularly post-COVID-19 conditions. Therefore, this review will answer how exercise intensity is crucial to reassure the exercise benefits for promoting safe participation before infection and post-COVID-19 conditions.

Home-based exercise alters pulmonary function and cellular stress markers in overweight middle-aged men during covid-19 Home quarantine

BACKGROUND

This study aimed to investigate the effects of a combined home-based exercise program on potential indicators of severe coronavirus disease 2019 (COVID-19) in overweight middle-aged men during home quarantine caused by COVID-19.

METHODS

Forty men (aged 45-64 years) were assigned to the exercise (EXE, n = 20) or control (CON, n = 20) groups. A 6-week combined program was carried out three days/week, starting at 20 min per session at 50% maximal heart rate (HRmax) and advancing to 45 min at 70% HRmax. Pulmonary functional and cellular stress biomarkers were measured before and after the training program. Analysis of the covariance (ANCOVA) was used for comparison between the two groups considering the baseline values.

RESULTS

Thirty-six participants (EXE, n = 17; CON, n = 19) completed the research protocol. The EXE group showed post-training improvements in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC, Vital capacity (VC), and Forced expiratory flow at 25-75% (FEF25-75) compared to the CON group (P < 0. 05). Further, the plasma levels of fibrinogen, Interleukin (IL)-6, Interleukin (IL)-1β, D-dimer, and angiotensin (Ang II) decreased in the EXE group compared to the CON group (P < 0. 05). After six weeks of the training program, leukocyte counts increased in the EXE group compared to the CON group (P < 0. 05). There was a significant positive correlation between body mass index (BMI) with cardiovascular and inflammatory biomarkers other than white blood cells (WBC) in the EXE group (P < 0.05).

CONCLUSIONS

The findings suggest that combined home-based exercise during home quarantine improves risk factors for severe COVID-19 in overweight middle-aged men. These improvements were further correlated with changes in BMI. Future research is required to confirm the findings of this study.

Inadequate Physical Activity Is Associated with Worse Physical Function in a Sample of COVID-19 Survivors with Post-Acute Symptoms

Background—Patients affected by Long COVID often report shorter times spent doing physical activity (PA) after COVID-19. The aim of the present study was to evaluate potential associations between PA levels and parameters of physical function in a cohort of COVID-19 survivors with post-acute symptoms, with a particular focus on individuals aged 65 and older. Materials and methods—PA levels before and after COVID-19 were assessed in a sample of patients that had recovered from COVID-19 and were admitted to a post-acute outpatient service at the Fondazione Policlinico Universitario Agostino Gemelli IRCCS (Rome, Italy). Participation in PA was operationalized as the engagement in leisure-time PA for at least 150 min per week in the last 3 months. Self-rated health and measures of physical performance and muscle strength were assessed. Results—Mean age of 1846 participants was 55.2 ± 14.4 years and 47% were women. Before COVID-19, inactivity was detected in 47% of the whole study population; only 28% maintained pre-COVID-19 PA engagement. Inactivity was more frequent in women. The stopping of physical activity was associated with increased BMI and CRP levels, lower vitamin D levels and a higher prevalence of post-COVID-19 fatigue, dyspnea, arthralgia, and myalgia. Active participants had higher handgrip strength and performed better on both the six-minute walking test (6MWT) and at the one-minute sit-to-stand test (1MSTST). In particular, at the 6MWT, participants 65 and older that were still active after COVID-19 walked 32 m more than sedentary peers. Moreover, the distance covered was 28 m more than those who were active only before COVID-19 (p = 0.05). Formerly active subjects performed similarly at the 6MWT to inactive participants. PA was associated with better self-rated health. Conclusions—Our findings reveal that inactivity is frequent in the post-acute COVID-19 phase. Stopping physical activity after COVID-19 results in measures of performance that are comparable to those who were never active. Relevant differences in the distance covered at the 6MWT were found between older active subjects and their sedentary peers.

Risk Factors of Severe COVID-19: A Review of Host, Viral and Environmental Factors

The clinical course and outcome of COVID-19 are highly variable, ranging from asymptomatic infections to severe disease and death. Understanding the risk factors of severe COVID-19 is relevant both in the clinical setting and at the epidemiological level. Here, we provide an overview of host, viral and environmental factors that have been shown or (in some cases) hypothesized to be associated with severe clinical outcomes. The factors considered in detail include the age and frailty, genetic polymorphisms, biological sex (and pregnancy), co- and superinfections, non-communicable comorbidities, immunological history, microbiota, and lifestyle of the patient; viral genetic variation and infecting dose; socioeconomic factors; and air pollution. For each category, we compile (sometimes conflicting) evidence for the association of the factor with COVID-19 outcomes (including the strength of the effect) and outline possible action mechanisms. We also discuss the complex interactions between the various risk factors.

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.

The role of physical activity in the clinical outcomes of people diagnosed with Covid-19: A systematic review

Objective

This review aimed to compile the evidence on PA and clinical outcomes of people receiving a positive diagnosis of covid-19.

Design

Systematic review.

Methods

The search was performed in five databases: EMBASE, MEDLINE via PubMed portal, Scopus, SPORTDiscus via EBSCO platform, and Web of Science. In addition, the "gray" literature was searched through Google Scholar and medRxiv published between January 2020 and July 2022. Studies were assessed for risk of bias, with the extraction of relevant data. Our search revealed a total of 10,028 studies.

Results

After applying the eligibility criteria 32 studies were included. Thirty-one studies were at low to moderate risk of bias. Physically active individuals, who were diagnosed with covid-19, presented attenuation of clinical outcomes, such as decreased risk of hospitalization, recovery time, number of symptoms, severity, and ICU and death when compared to individuals with low levels of PA or classified as sedentary.

Conclusions

Physically active individuals when diagnosed with covid-19 may have decreased risk of several clinical outcomes related to covid-19, including but not limited to hospitalization and number of symptoms. Public health authorities should develop strategies and initiatives that promote safe PA environments to improve the clinical prognosis of people diagnosed with covid-19.

Study registration

Open Science Framework (OSF), DOI registry 10.17605/OSF.IO/PV6NF. It can be consulted through the access link: https://doi.org/10.17605/OSF.IO/PV6NF, October 07, 2021.

Physical activity and risk of infection, severity and mortality of COVID-19: a systematic review and non-linear dose-response meta-analysis of data from 1 853 610 adults

OBJECTIVE

To quantify the association between physical activity and risk of SARS-CoV-2 infection, COVID-19-associated hospitalisation, severe illness and death due to COVID-19 in adults.

DESIGN

A systematic review and meta-analysis.

DATA SOURCES

Three databases were systematically searched through March 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Peer-reviewed articles reporting the association between regular physical activity and at least one COVID-19 outcome in adults were included. Risk estimates (ORs, relative risk (RR) ratios or HRs) were extracted and pooled using a random-effects inverse-variance model.

RESULTS

Sixteen studies were included (n=1 853 610). Overall, those who engaged in regular physical activity had a lower risk of infection (RR=0.89; 95% CI 0.84 to 0.95; I2=0%), hospitalisation (RR=0.64; 95% CI 0.54 to 0.76; I2=48.01%), severe COVID-19 illness (RR=0.66; 95% CI 0.58 to 0.77; I2=50.93%) and COVID-19-related death (RR=0.57; 95% CI 0.46 to 0.71; I2=26.63%) as compared with their inactive peers. The results indicated a non-linear dose-response relationship between physical activity presented in metabolic equivalent of task (MET)-min per week and severe COVID-19 illness and death (p for non-linearity <0.001) with a flattening of the dose-response curve at around 500 MET-min per week.

CONCLUSIONS

Regular physical activity seems to be related to a lower likelihood of adverse COVID-19 outcomes. Our findings highlight the protective effects of engaging in sufficient physical activity as a public health strategy, with potential benefits to reduce the risk of severe COVID-19. Given the heterogeneity and risk of publication bias, further studies with standardised methodology and outcome reporting are now needed.

PROSPERO REGISTRATION NUMBER

CRD42022313629.

COVID-19 and preventive strategy

In December 2019, an unprecedented outbreak of the novel coronavirus disease 2019 (COVID-19), an infectious disease caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) began to spread internationally, now impacting more than 293,750,692 patients with 5,454,131 deaths globally as of January 5, 2022. COVID-19 is highly pathogenic and contagious which has caused a large-scale epidemic impacting more deaths than the severe acute respiratory syndrome (SARS) epidemic in 2002-2003 or the Middle East respiratory syndrome (MERS) epidemic in 2012-2013. Although COVID-19 symptoms are mild in most people, in those with pre-existing comorbidities there is an increased risk of progression to severe disease and death. In an attempt to mitigate this pandemic, urgent public health measures including quarantining exposed individuals and social distancing have been implemented in most states, while some states have even started the process of re-opening after considering both the economic and public health consequences of social distancing measures. While prevention is crucial, both novel agents and medications already in use with other indications are being investigated in clinical trials for patients with COVID-19. The collaboration between healthcare providers, health systems, patients, private sectors, and local and national governments is needed to protect both healthcare providers and patients to ultimately overcome this pandemic. The purpose of this review is to summarize the peer-reviewed and preprint literature on the epidemiology, transmission, clinical presentation, and available therapies as well as to propose a preventive strategy to overcome the present global pandemic.

Long-Term Effect of Physical Exercise on the Risk for Hospitalization and Death in Dialysis Patients: A Post-Trial Long-Term Observational Study

BACKGROUND AND OBJECTIVES

In the EXerCise Introduction to Enhance Performance in Dialysis (EXCITE) trial, a simple, personalized 6-month walking exercise program at home during the day off of dialysis improved the functional status and the risk for hospitalization in patients with kidney failure. In this post-trial observational study, we tested whether the same intervention was associated with a lower long-term risk of death or hospitalization (combined end point) during a follow-up extended up to 36 months.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In total, 227 patients (exercise, n=104; control, n=123) completed the 6-month trial and entered the post-trial observational study. Data were analyzed by unadjusted and adjusted Cox regression analyses and Bayesian analysis.

RESULTS

In the long-term observation (up to 36 months), 134 events were recorded (eight deaths not preceded by hospitalization and 126 hospitalizations, which were followed by death in 38 cases). The long-term risk for hospitalization or death was 29% lower (hazard ratio, 0.71; 95% confidence interval, 0.50 to 1.00), and in an analysis stratified by adherence to the walking exercise program during the 6-month trial, the subgroup with high adherence (>60% of prescribed sessions) had a 45% lower risk as compared with the control group (hazard ratio, 0.55; 95% confidence interval, 0.35 to 0.87). A Bayesian analysis showed that the posterior probability of a hazard ratio of 0.71 (95% confidence interval, 0.50 to 1.00) for the risk of the composite outcome observed in the post-trial observational study was 93% under the conservative prior and 97% under the optimistic prior. Sensitivity analyses restricted to the risk of hospitalization only or censoring patients at the time of transplantation fully confirmed these findings.

CONCLUSIONS

A simple, personalized, home-based, low-intensity exercise program was associated with a lower risk of hospitalization.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

EXerCise Introduction to Enhance Performance in Dialysis (EXCITE), NCT01255969.

The Importance of Behavioral and Native Factors on COVID-19 Infection and Severity: Insights from a Preliminary Cross-Sectional Study

The COVID-19 pandemic has had a major impact on a global scale. Understanding the innate and lifestyle-related factors influencing the rate and severity of COVID-19 is important for making evidence-based recommendations. This cross-sectional study aims at establishing a potential relationship between human characteristics and vulnerability/resistance to SARS-CoV-2. We hypothesize that the impact of the virus is not the same due to cultural and ethnic differences. A cross-sectional study was performed using an online questionnaire. The methodology included the development of a multi-language survey, expert evaluation, and data analysis. Data were collected using a 13-item pre-tested questionnaire based on a literature review between 9 December 2020 and 21 July 2021. Data were statistically analyzed using logistic regression. For a total of 1125 respondents, 332 (29.5%) were COVID-19 positive; among them, 130 (11.5%) required home-based treatment, and 14 (1.2%) intensive care. The significant and most influential factors on infection included age, physical activity, and health status (p < 0.05), i.e., better physical activity and better health status significantly reduced the possibility of infection, while older age significantly increased it. The severity of infection was negatively associated with the acceptance (adherence and respect) of preventive measures and positively associated with tobacco (p < 0.05), i.e., smoking regularly significantly increases the severity of COVID-19 infection. This suggests the importance of behavioral factors compared to innate ones. Apparently, individual behavior is mainly responsible for the spread of the virus. Therefore, adopting a healthy lifestyle and scrupulously observing preventive measures, including vaccination, would greatly limit the probability of infection and prevent the development of severe COVID-19.

Associations between physical activity prior to infection and COVID-19 disease severity and symptoms: results from the prospective Predi-COVID cohort study

OBJECTIVE

To investigate if the physical activity (PA) prior to infection is associated with the severity of the disease in patients positively tested for COVID-19, as well as with the most common symptoms.

DESIGN

A cross-sectional study using baseline data from a prospective, hybrid cohort study (Predi-COVID) in Luxembourg. Data were collected from May 2020 to June 2021.

SETTING

Real-life setting (at home) and hospitalised patients.

PARTICIPANTS

All volunteers aged >18 years with confirmed SARS-CoV-2 infection, as determined by reverse transcription-PCR, and having completed the PA questionnaire (n=452).

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was disease severity (asymptomatic, mild illness and moderate illness). The secondary outcomes were self-reported symptoms.

RESULTS

From the 452 patients included, 216 (48%) were female, the median (IQR) age was 42 (31-51) years, 59 (13%) were classified as asymptomatic, 287 (63%) as mild illness and 106 (24%) as moderate illness. The most prevalent symptoms were fatigue (n=294; 65%), headache (n=281; 62%) and dry cough (n=241; 53%). After adjustment, the highest PA level was associated with a lower risk of moderate illness (OR 0.37; 95% CI 0.14 to 0.98, p=0.045), fatigue (OR 0.54; 95% CI 0.30 to 0.97, p=0.040), dry cough (OR 0.55; 95% CI 0.32 to 0.96, p=0.034) and chest pain (OR 0.32; 95% CI 0.14 to 0.77, p=0.010).

CONCLUSIONS

PA before COVID-19 infection was associated with a reduced risk of moderate illness severity and a reduced risk of experiencing fatigue, dry cough and chest pain, suggesting that engaging in PA may be an effective approach to minimise the severity of COVID-19.

TRIAL REGISTRATION NUMBER

NCT04380987.

Protective Effects of Exercise Become Especially Important for the Aging Immune System in The Covid-19 Era

Aging is a complex, multietiological process and a major risk factor for most non-genetic, chronic diseases including geriatric syndromes that negatively affect healthspan and longevity. In the scenario of "healthy or good aging", especially during the COVID-19 era, the proper implementation of exercise as "adjuvant" or "polypill" to improve disease-related symptoms and comorbidities in the general population is a top priority. However, there is still a gap concerning studies analyzing influence of exercise training to immune system in older people. Therefore, the aim of this review is to provide a brief summary of well-established findings in exercise immunology and immunogerontology, but with a focus on the main exercise-induced mechanisms associated with aging of the immune system (immunosenescence). The scientific data strongly supports the notion that regular exercise as a low-cost and non-pharmacological treatment approach, when adjusted on an individual basis in elderly, induce multiple rejuvenating mechanisms: (1) affects the telomere-length dynamics (a "telo-protective" effect), (2) promote short- and long-term anti-inflammatory effects (via e.g., triggering the anti-inflammatory phenotype), 3) stimulates the adaptive immune system (e.g., helps to offset diminished adaptive responses) and in parallel inhibits the accelerated immunosenescence process, (4) increases post-vaccination immune responses, and (5) possibly extends both healthspan and lifespan.

SARS-COV-2 in Type 2 Diabetic Patients: Possible Roles of Exercise Training as a Medicine

SARS-COV-2 is the novel type of beta coronavirus that was first evolved in December 2019 in Wuhan, China. People with type 2 diabetes are the most vulnerable group to SARS-COV-2 and its associated complications. Many factors such as medication, pathophysiologic-induced compensatory mechanisms, and alterations in protein expression and immune system function can all contribute to severe outcomes in diabetics. In this review article, we first described the possible mechanisms of increased risk and more severe complications rate of SARS-COV-2 in diabetic patients. Secondly, we discussed the crucial role of exercise in diabetic patients in balancing the RAS system (ACE2/ACE). Finally, we examine the possible roles of acute and chronic exercise in reducing SARS-COV-2 severe outcomes in people with diabetes in accordance with the latest evidence. We concluded that regular exercise (especially moderate-intensity exercise) can play a role in immune- enhancing, anti-inflammatory, and anti-oxidant activities and can balance the ACE2/ACE ratio (decreasing ANG2 levels) in diabetic subjects.

Forest-bathing and physical activity as weapons against COVID-19: a review

Strengthening the immune system in order to better withstand the threat of COVID-19 is an important way to ensure the protection of our health against the current pandemic associated with SARS-CoV-2. There are many ways to achieve this, but with current circumstances, certain modalities stand out as being the most valid and are certainly worth greater consideration. Here we review the effects that particular immuno-strengthening activities can have on limiting the severity of COVID-19 disease as well as preventing virus infection. Physical activity, in particular, should not be discounted as an important method of prevention of viral diseases as it triggers many biological processes within the human body which in turn lead to heightened natural defences against viral infections. When exercise is performed in forested areas, these protective health benefits may be increased since many plant species emit biogenic volatile compounds (VOCs) which, when inhaled, have many protective properties. These VOCs have been shown in particular to have immunostimulatory effects on the human body and, thus, they could be of use in the prevention and/or treatment of COVID-19. Being amongst trees may also help to alleviate stress and anxiety, lowering cortisol levels and consequently helping the proper functioning of the immune system. In the following work, we have performed an analysis of the available scientific literature which looks at the effects of physical exercise as well as 'forest-bathing' on the immune system's ability to fight disease, especially of course as it relates to COVID-19. Our review aims at shedding light on the benefits of exercising outdoors in green areas and suggests reforestation as a protective measure against future outbreaks.

Dysregulated Inflammation During Obesity: Driving Disease Severity in Influenza Virus and SARS-CoV-2 Infections

Acute inflammation is a critical host defense response during viral infection. When dysregulated, inflammation drives immunopathology and tissue damage. Excessive, damaging inflammation is a hallmark of both pandemic influenza A virus (IAV) infections and Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) infections. Chronic, low-grade inflammation is also a feature of obesity. In recent years, obesity has been recognized as a growing pandemic with significant mortality and associated costs. Obesity is also an independent risk factor for increased disease severity and death during both IAV and SARS-CoV-2 infection. This review focuses on the effect of obesity on the inflammatory response in the context of viral respiratory infections and how this leads to increased viral pathology. Here, we will review the fundamentals of inflammation, how it is initiated in IAV and SARS-CoV-2 infection and its link to disease severity. We will examine how obesity drives chronic inflammation and trained immunity and how these impact the immune response to IAV and SARS-CoV-2. Finally, we review both medical and non-medical interventions for obesity, how they impact on the inflammatory response and how they could be used to prevent disease severity in obese patients. As projections of global obesity numbers show no sign of slowing down, future pandemic preparedness will require us to consider the metabolic health of the population. Furthermore, if weight-loss alone is insufficient to reduce the risk of increased respiratory virus-related mortality, closer attention must be paid to a patient’s history of health, and new therapeutic options identified.

Moderate Intensity Aerobic Exercise Potential Favorable Effect Against COVID-19: The Role of Renin-Angiotensin System and Immunomodulatory Effects

The coronavirus disease (COVID-19) pandemic is caused by a novel coronavirus (CoV) named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As the angiotensin converting enzyme 2 (ACE2) is the cellular receptor of SARS-CoV-2, it has a strong interaction with the renin angiotensin system (RAS). Experimental studies have shown that the higher levels of ACE2 or increasing ACE2/ACE1 ratio improve COVID-19 outcomes through lowering inflammation and death. Aerobic moderate intensity physical exercise fights off infections by two mechanisms, the inhibition of ACE/Ang II/AT1-R pathway and the stimulation of ACE2/Ang-(1-7)/MasR axis. Exercise can also activate the anti-inflammatory response so that it can be a potential therapeutic strategy against COVID-19. Here, we summarize and focus the relation among COVID-19, RAS, and immune system and describe the potential effect of aerobic moderate intensity physical exercise against CoV as a useful complementary tool for providing immune protection against SARS-CoV-2 virus infection, which is a novel intervention that requires further investigation.

Psychosocial Health and Physical Activity in People With Major Depression in the Context of COVID-19

Introduction: Major depression is a psychiatric disease associated with physical inactivity, which in turn affects mental and physical health. A randomized controlled trial is being implemented to facilitate physical activity in people with major depression. In March 2020, Swiss state authorities temporarily legislated a lockdown to contain the Coronavirus disease-19 (COVID-19), which influenced health, behavior and research. The aim of this study was to find out whether data gathered before and during/after the lockdown among in-patients with major depression differ with regard to psychosocial health, physical activity and related attitudes and to establish whether baseline data have been affected by the lockdown. Methods: This is a cross-sectional analysis within a randomized controlled trial. Physically inactive, adult in-patients diagnosed with major depression were recruited from four Swiss psychiatric clinics between January 2019 and December 2020. Psychosocial health was measured with questionnaires pertaining to stress, sleep and health-related quality of life. Physical activity was measured with the Simple Physical Activity Questionnaire. Explicit attitudes were measured with seven questionnaires pertaining to physical activity-related motivation and volition. Implicit attitudes toward physical activity were captured with a single target implicit association test. Results: The sample consisted of 165 participants (n = 119 before lockdown, n = 46 during/after lockdown). No statistically significant differences were found between in-patients with major depression assessed before and during/after the COVID-19 lockdown with regard to psychosocial health (stress, p = 0.51; sleep, p = 0.70; physical component of health-related quality of life, p = 0.55; mental component of health-related quality of life, p = 0.64), self-reported physical activity (p = 0.16) and explicit as well as implicit attitudes toward physical activity (p = 0.94). Hence, the COVID-19-induced lockdown seems not to have led to group differences. Conclusion: Baseline data gathered in in-patients suffering from major depression who are physically inactive upon admission to in-patient treatment in Switzerland seem to be unaffected by the COVID-19-induced lockdown. To assess changes in said population regarding psychosocial health and physical activity patterns over time, longitudinal data are needed.

Circulating extracellular vesicles delivering beneficial cargo as key players in exercise effects

Exercise has been recognized as an effective preventive and therapeutic approach for numerous diseases. This review addresses the potential role of circulating extracellular vesicles (EV) cargo that is modulated by physical activity. EV transport and deliver beneficial molecules to adjacent and distant tissues as a whole-body phenomenon, resulting in a healthier global status. Several candidate EV molecules, especially miRNAs, are summarized here as mediators of the beneficial effects of exercise, using different modalities, frequencies, volumes, and intensities. The following are among the candidate miRNAs: miR-21, miR-146, miR-486, miR-148a-3p, miR-223-3p, miR-142-3p, and miR-191a-5p. We highlight the relationship between EV cargo modifications, their targets and pathway interactions, in clinical outcomes, for example, on cardiovascular or immune diseases. This review brings an innovative perspective providing evidence for an intricate biological basis of the relationship between EV cargo and exercise-induced benefits on several diseases. Moreover, specific changes on circulating EV content might potentially be used as biomarkers of exercise efficacy.

Effects of Vaccination Day Routine Activities on Influenza Vaccine Efficacy and Vaccination-Induced Adverse Reaction Incidence: A Cohort Study

We aimed to investigate the effect of vaccination day routine activities on the influenza vaccine efficacy and vaccination-induced adverse reaction incidence. Study participants were workers at three hospitals in the Hyogo Prefecture, Japan, who received the influenza vaccine between October and November, 2018 and 2019. Their data were collected using a questionnaire. The main factors, which were examined for vaccination day routine activities, were personal hygiene (bathing), smoking, alcohol consumption, caffeine intake, and exercise. The main outcome markers included influenza incidence during the winter season and vaccination-induced local or systemic adverse reaction incidence. The risk ratio for the main factors of vaccination day routine activities was calculated against the main outcome markers using the modified Poisson regression. Overall, 3780 people received the influenza vaccination, and 2731 submitted the questionnaire. We found that vaccination day routine activities did not affect the influenza vaccine efficacy, and engaging in strenuous exercise on the vaccination day tended to cause systemic adverse reactions. Moreover, lifestyle-related activities had no impact on the incidence of systemic or local adverse reactions. Therefore, it is advisable to only avoid strenuous physical exercise, and no other lifestyle-related restrictions are necessary on the day of influenza vaccination.

The central role of mitochondrial fitness on antiviral defenses: An advocacy for physical activity during the COVID-19 pandemic

Mitochondria are central regulators of cellular metabolism, most known for their role in energy production. They can be "enhanced" by physical activity (including exercise), which increases their integrity, efficiency and dynamic adaptation to stressors, in short "mitochondrial fitness". Mitochondrial fitness is closely associated with cardiorespiratory fitness and physical activity. Given the importance of mitochondria in immune functions, it is thus not surprising that cardiorespiratory fitness is also an integral determinant of the antiviral host defense and vulnerability to infection. Here, we first briefly review the role of physical activity in viral infections. We then summarize mitochondrial functions that are relevant for the antiviral immune response with a particular focus on the current Coronavirus Disease (COVID-19) pandemic and on innate immune function. Finally, the modulation of mitochondrial and cardiorespiratory fitness by physical activity, aging and the chronic diseases that represent the most common comorbidities of COVID-19 is discussed. We conclude that a high mitochondrial - and related cardiorespiratory - fitness should be considered as protective factors for viral infections, including COVID-19. This assumption is corroborated by reduced mitochondrial fitness in many established risk factors of COVID-19, like age, various chronic diseases or obesity. We argue for regular analysis of the cardiorespiratory fitness of COVID-19 patients and the promotion of physical activity - with all its associated health benefits - as preventive measures against viral infection.

Prognostic value of cardiopulmonary exercise test after heart transplantation

BACKGROUND

The clinical utility of cardiopulmonary exercise testing (CPET) has not been extensively studied yet in heart transplantation (HTX) patients.

OBJECTIVE

To analyze the predictive value of the CPET on hospitalizations and mortality in HTX recipients.

METHODS

A retrospective cohort was performed from a secondary database. Patients > 18 years with HTX who underwent a CPET between 3 and 12 months after transplantation were included. Time to the first primary endpoint (HTX-related hospitalization) was analyzed and adjusted using Cox proportional hazards regression model.

RESULTS

A total of 122 patients (mean age 50.1 years, 77.0% men) were included. Fifty-seven patients (46.7%) had the primary endpoint. Peak VO₂ (HR .95; CI 95% .90-.99, P = .03), oxygen pulse (HR .57; CI 95% .34-.96, P = .03) and predicted VO₂ (HR .97; CI 95% .96-.99, P = .002) were associated with the endpoint. We did not find a significant association between the other variables and the outcome.

CONCLUSION

In HTX recipients, peak VO₂ , oxygen pulse, and predicted VO₂ were independently associated with hospitalizations at follow up.

Does Higher Self-Reported Cardiorespiratory Fitness Reduce the Odds of Hospitalization From COVID-19?

BACKGROUND

Regular physical activity and higher cardiorespiratory (CR) fitness enhance immune function, possibly reducing coronavirus disease 2019 (COVID-19) infection severity. The aim was to assess the association between physical activity and self-reported CR fitness on COVID-19 infection characteristics.

METHODS

Participants formerly testing positive for COVID-19 completed an online questionnaire measuring COVID-19 infection characteristics and complications, self-reported CR fitness level, physical activity, and sociodemographic and health-related characteristics. Self-reported CR fitness was determined as the pace to cover 4.8 km without becoming overly fatigued (with slow walking, brisk walking, jogging, and running corresponding to low, moderate, good, and excellent levels of fitness, respectively).

RESULTS

A total of 263 individuals completed the survey. Compared with the lowest level of self-reported CR fitness, the odds of hospitalization significantly decreased by 64% (odds ratio = 0.36; 95% confidence interval, 0.13-0.98; P = .04) in individuals reporting the ability to maintain a brisk walk. In individuals reporting the ability to maintain a jogging pace, the further reduction in hospitalization was not significant (odds ratio = 0.22; 95% confidence interval, 0.05-1.04; P = .05). For COVID-19 symptom severity and number, there were no significant associations with self-reported CR fitness or physical activity levels.

CONCLUSIONS

For individuals with low self-reported CR fitness, improving CR fitness represents a strategy to reduce the risk of hospitalization from COVID-19.

Lifestyle and rehabilitation during the COVID-19 pandemic: guidance for health professionals and support for exercise and rehabilitation programs

Introduction: The coronavirus disease-2019 (COVID-19) is a highly contagious respiratory viral disease for both the general population and healthcare professionals caring for infected patients. Of particular concern is the potential for significant respiratory, cardiovascular, physical, and psychological dysfunctions.Areas covered: In this context, the current review will focus on the following areas: 1) staying physically active during the COVID-19 pandemic; 2) highlighting the importance of understanding COVID-19 mechanisms; 3) preventing infections for healthcare workers by using personal protective equipment; 4) highlighting importance of respiratory care and physical therapy during hospitalization in patients with COVID-19; and 5) facilitating referral to a rehabilitation program in patients recovering from COVID-19.Expert opinion: We recommend daily physical exercise, outdoors or at home, as physical exercise increases the synthesis of anti-inflammatory cytokines; Patients with COVID-19 may develop severe acute respiratory syndrome, hypoxemia, diffuse alveolar damage, ACE2 reduction in the cardiovascular system and muscle weakness acquired through a prolonged hospital stay; The role of the physiotherapist in the hospital environment is of fundamental importance-early mobilization is highly recommended in severe cases of COVID-19.

Physical Activity and the Risk of COVID-19 Infection and Mortality: A Nationwide Population-Based Case-Control Study

Regular physical activity (PA) is known to reduce the risk of serious community-acquired infections. We examined the association of PA with the morbidity and mortality resulting from coronavirus disease (COVID-19) infection in the South Korean population. Patients who tested positive for severe acute respiratory coronavirus 2 and who underwent public health screening between 2014 and 2017 (n = 6288) were included. Age- and sex-matched controls (n = 125,772) were randomly selected from the Korean National Health Insurance Service database. Leisure-time PA was assessed using a self-reported questionnaire. The mean PA levels were lower in the patient than in the control group (558.2 ± 516.3 vs. 580.2 ± 525.7 metabolic equivalent of task (MET)-min/week, p = 0.001). Patients with moderate to vigorous PA (MVPA) were associated with a lower risk of COVID-19 morbidity (odds ratio (OR), 0.90; 95% confidence interval (CI), 0.86-0.95). In addition, a standard deviation (SD) increment in MET/week (525.3 MET-min/week) was associated with a 4% decrease in the risk of COVID-19 morbidity (OR, 0.96; 95% CI, 0.93-0.99). MVPA and an SD increment in MET/week were associated with lower mortality (MVPA: OR, 0.47; 95% CI, 0.26-0.87; per SD increment: OR, 0.65; 95% CI, 0.48-0.88). Higher levels of regular PA were associated with a lower risk of COVID-19 infection and mortality, highlighting the importance of maintaining appropriate levels of PA along with social distancing amid the COVID-19 pandemic.

Physical activity recommendations during the COVID-19 pandemic: a practical approach for different target groups

Introduction

Ensuring health and well-being during this pandemic is essential according to the United Nations Sustainable Development Goals. Physical exercise has an important role in the preservation of the immune system, which is vital to prevent infections. To promote physical exercise and maintain a healthy status, recent studies have suggested general exercise routines to be implemented during the quarantine period. However, to improve the health-related physical fitness components, any specific prescription should include intensity, volume, duration, and mode. Controversy persists about which is the best intensity of physical activity, while performing exercise at a moderate intensity could bring important benefits to asymptomatic people. High intensity or unaccustomed exercise should be restricted for older people, and for people of all ages with chronic diseases or compromised immune system, obesity, or upper respiratory tract infection with limited symptoms. Besides, physical activity guidelines should be particular to each population group, giving special consideration to those vulnerable to COVID-19 who are much more likely to suffer more self-isolation. Therefore, the present study is to provide specific physical activity recommendations for different populations during this pandemic.

A Pandemic within the Pandemic? Physical Activity Levels Substantially Decreased in Countries Affected by COVID-19

Governments have restricted public life during the COVID-19 pandemic, inter alia closing sports facilities and gyms. As regular exercise is essential for health, this study examined the effect of pandemic-related confinements on physical activity (PA) levels. A multinational survey was performed in 14 countries. Times spent in moderate-to-vigorous physical activity (MVPA) as well as in vigorous physical activity only (VPA) were assessed using the Nordic Physical Activity Questionnaire (short form). Data were obtained for leisure and occupational PA pre- and during restrictions. Compliance with PA guidelines was calculated based on the recommendations of the World Health Organization (WHO). In total, n = 13,503 respondents (39 ± 15 years, 59% females) were surveyed. Compared to pre-restrictions, overall self-reported PA declined by 41% (MVPA) and 42.2% (VPA). Reductions were higher for occupational vs. leisure time, young and old vs. middle-aged persons, previously more active vs. less active individuals, but similar between men and women. Compared to pre-pandemic, compliance with WHO guidelines decreased from 80.9% (95% CI: 80.3–81.7) to 62.5% (95% CI: 61.6–63.3). Results suggest PA levels have substantially decreased globally during the COVID-19 pandemic. Key stakeholders should consider strategies to mitigate loss in PA in order to preserve health during the pandemic.

The Relevance of a Physical Active Lifestyle and Physical Fitness on Immune Defense: Mitigating Disease Burden, With Focus on COVID-19 Consequences

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a fast spreading virus leading to the development of Coronavirus Disease-2019 (COVID-19). Severe and critical cases are characterized by damage to the respiratory system, endothelial inflammation, and multiple organ failure triggered by an excessive production of proinflammatory cytokines, culminating in the high number of deaths all over the world. Sedentarism induces worse, continuous, and progressive consequences to health. On the other hand, physical activity provides benefits to health and improves low-grade systemic inflammation. The aim of this review is to elucidate the effects of physical activity in physical fitness, immune defense, and its contribution to mitigate the severe inflammatory response mediated by SARS-CoV-2. Physical exercise is an effective therapeutic strategy to mitigate the consequences of SARS-CoV-2 infection. In this sense, studies have shown that acute physical exercise induces the production of myokines that are secreted in tissues and into the bloodstream, supporting its systemic modulatory effect. Therefore, maintaining physical activity influence balance the immune system and increases immune vigilance, and also might promote potent effects against the consequences of infectious diseases and chronic diseases associated with the development of severe forms of COVID-19. Protocols to maintain exercise practice are suggested and have been strongly established, such as home-based exercise (HBE) and outdoor-based exercise (OBE). In this regard, HBE might help to reduce levels of physical inactivity, bed rest, and sitting time, impacting on adherence to physical activity, promoting all the benefits related to exercise, and attracting patients in different stages of treatment for COVID-19. In parallel, OBE must improve health, but also prevent and mitigate COVID-19 severe outcomes in all populations. In conclusion, HBE or OBE models can be a potent strategy to mitigate the progress of infection, and a coadjutant therapy for COVID-19 at all ages and different chronic conditions.

Sedentary behavior, exercise and COVID-19: immune and metabolic implications in obesity and its comorbidities

Many reports showed a dramatic decrease in the levels of physical activity during the current pandemic of SARS-CoV-2. This has substantial immune and metabolic implications, especially in those at risk or with metabolic diseases including individuals with obesity and Type 2 diabetes. In this study we discussed the route from physical inactivity to immune and metabolic aberrancies; focusing on how insulin resistance could represent an adaptive mechanism to the low physical activity levels and on how such an adaptive mechanism could shift to a pathognomonic feature of metabolic diseases, creating a vicious circle of immune and metabolic aberrancies. We provide a theoretical framework to the severe immunopathology of COVID-19 in patients with metabolic diseases. We finally discuss the idea of exercise as a potential adjuvant against COVID-19 and emphasize how even interrupting prolonged periods of sitting with short time breaks of very light activity could be a feasible strategy to limit the deleterious effects of the outbreak.

Lifestyle factors in the prevention of COVID-19

Confinement to the home and psychological distress due to the coronavirus disease 2019 (COVID-19) pandemic may lead to harmful health behaviors, such as overeating, sedentary behavior with reduced physical activity, elevated alcohol and tobacco use and increased screen time causing impaired sleep. All of these behaviors are associated with non-communicable diseases and can interfere with immunity. While no foods, single nutrients or dietary supplements are capable of preventing infection with COVID-19, a balanced diet containing sufficient amounts of macronutrients and diverse micronutrients is a prerequisite of an optimally functioning immune system. High-energy "Western" diets and obesity are major risk factors for a more severe course of COVID-19. Alcohol use and tobacco also have detrimental effects on the immune system. Therefore, population-wide body weight control, reduction of smoking rates and limitation of alcohol consumption are important preventive measures. Furthermore, sufficient restorative sleep is needed for adequate immune functioning. Appropriate lifestyle changes in regard to nutrition, exercise, sleep, smoking and alcohol intake may help shift the population distribution of infection risk and aid in preventing severe COVID-19 disease. Large-scale surveys should explore the effects of lifestyle changes, and the provision of reliable lifestyle information and effective interventions to individuals and communities during the pandemic is a pressing need.

Molecular mechanisms involved in the positive effects of physical activity on coping with COVID-19

PURPOSE

Physical activity (PA) represents the first line of defence against diseases characterised by increased inflammation status, such as metabolic and infectious diseases. Conversely, a sedentary lifestyle-associated with obesity, type 2 diabetes and cardiovascular disorders-negatively impacts on general health status, including susceptibility to infections. At a time of a pandemic SARS-CoV2 infection, and in the context of the multiorgan crosstalk (widely accepted as a mechanism participating in the pathophysiology of all organs and systems), we examine the complex interplay mediated by skeletal muscle contraction involving the immune system and how this contributes to control health status and to counteract viral infections. In so doing, we review the molecular mechanisms and expression of molecules modulated by PA, able to provide the proper molecular equipment against viral infections such as the current SARS-CoV2.

METHODS

A critical review of the literature was performed to elucidate the molecular mechanisms and mediators induced by PA that potentially impact on viral infections such as SARS-CoV2.

RESULTS

We showed the effects mediated by regular moderate PA on viral adverse effects through the regulation of biological processes involving the crosstalk between skeletal muscle, the immune system and adipose tissue. Evidence was provided of the effects mediated by modulation of the expression of inflammation markers.

CONCLUSION

A tigth association between PA and reduction in inflammation status allows effective counteracting of SARS-CoV2 infection. It is therefore essential to persuade people to keep active.

SARS-CoV-2 and mitochondrial health: implications of lifestyle and ageing

Infection with SARs-COV-2 displays increasing fatality with age and underlying co-morbidity, in particular, with markers of the metabolic syndrome and diabetes, which seems to be associated with a "cytokine storm" and an altered immune response. This suggests that a key contributory factor could be immunosenescence that is both age-related and lifestyle-induced. As the immune system itself is heavily reliant on mitochondrial function, then maintaining a healthy mitochondrial system may play a key role in resisting the virus, both directly, and indirectly by ensuring a good vaccine response. Furthermore, as viruses in general, and quite possibly this new virus, have also evolved to modulate immunometabolism and thus mitochondrial function to ensure their replication, this could further stress cellular bioenergetics. Unlike most sedentary modern humans, one of the natural hosts for the virus, the bat, has to "exercise" regularly to find food, which continually provides a powerful adaptive stimulus to maintain functional muscle and mitochondria. In effect the bat is exposed to regular hormetic stimuli, which could provide clues on how to resist this virus. In this paper we review the data that might support the idea that mitochondrial health, induced by a healthy lifestyle, could be a key factor in resisting the virus, and for those people who are perhaps not in optimal health, treatments that could support mitochondrial function might be pivotal to their long-term recovery.

Promising effects of exercise on the cardiovascular, metabolic and immune system during COVID-19 period

With 4 billion people in lockdown in the world, COVID-19 outbreak may result in excessive sedentary time, especially in the population of vulnerable and disabled subjects. In many chronic disorders and diseases including type 2 diabetes mellitus and hypertension, cardiovascular and immune beneficial effects of exercise interventions should be reminded.

Molecular mechanisms involved in the positive effects of physical activity on coping with COVID-19

PURPOSE

Physical activity (PA) represents the first line of defence against diseases characterised by increased inflammation status, such as metabolic and infectious diseases. Conversely, a sedentary lifestyle-associated with obesity, type 2 diabetes and cardiovascular disorders-negatively impacts on general health status, including susceptibility to infections. At a time of a pandemic SARS-CoV2 infection, and in the context of the multiorgan crosstalk (widely accepted as a mechanism participating in the pathophysiology of all organs and systems), we examine the complex interplay mediated by skeletal muscle contraction involving the immune system and how this contributes to control health status and to counteract viral infections. In so doing, we review the molecular mechanisms and expression of molecules modulated by PA, able to provide the proper molecular equipment against viral infections such as the current SARS-CoV2.

METHODS

A critical review of the literature was performed to elucidate the molecular mechanisms and mediators induced by PA that potentially impact on viral infections such as SARS-CoV2.

RESULTS

We showed the effects mediated by regular moderate PA on viral adverse effects through the regulation of biological processes involving the crosstalk between skeletal muscle, the immune system and adipose tissue. Evidence was provided of the effects mediated by modulation of the expression of inflammation markers.

CONCLUSION

A tigth association between PA and reduction in inflammation status allows effective counteracting of SARS-CoV2 infection. It is therefore essential to persuade people to keep active.

Is Exercise the Best Medicine during a COVID-19 Pandemic? Comment on Constandt, B.; Thibaut, E.; De Bosscher, V.; Scheerder, J.; Ricour, M.; Willem, A. Exercising in Times of Lockdown: An Analysis of the Impact of COVID-19 on Levels and Patterns of Exercise among Adults in Belgium. Int. J. Environ. Res. Public Health 2020, 17, 4144

From Constandt et al.'s survey of 13,515 Belgium respondents, regular physical activity can be successfully initiated and sustained during a lockdown, with appropriate social distancing measures. Documentation that 77% of highly active people and 58% of low active people exercised as much or more following the institution of a nationwide lockdown was impressive, given that the cases of COVID-19 were accelerating at that time. The Belgian government's central promotion of exercise, to boost both the mental and physical health of the population, likely contributed to the health, tolerance, and ultimate success of lockdown. In this commentary, we wish to pose a follow-up query which highlights the potential detrimental effects of intense exercise (competition) performed without social distancing measures. The proposed graphical abstract elucidates these possible risks, in contrast to the favorable results outlined in Constandt et al.'s study.

Exercise in the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) era: A Question and Answer session with the experts Endorsed by the section of Sports Cardiology & Exercise of the European Association of Preventive Cardiology (EAPC)

Regular exercise has multiple benefits for physical and mental health, including the body's ability to combat infections. The current COVID-19 pandemic and the social distancing measures employed to curtail the impact of the infection are likely to reduce the amount of usual physical activity being performed by most individuals, including habitual exercisers. The uncertainties relating to the impact of the SARS-CoV-2 virus on the heart may cause increased anxiety, particularly in athletes who need to sustain a vigorous exercise regime in order to maintain their skills and fitness in preparation for return to competition after a short re-training period. The aim of this document is to provide practical answers to pertinent questions being posed by the sporting community, in an attempt to offer reassurance, promote safe participation in exercise during as well as after the COVID-19 pandemic and provide a framework of management for physicians caring for athletes.

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.

Activity and Health During the SARS-CoV2 Pandemic (ASAP): Study Protocol for a Multi-National Network Trial

Introduction: The worldwide spread of the novel coronavirus (SARS-CoV2) has prompted numerous countries to restrict public life. Related measures, such as limits on social gatherings, business closures, or lockdowns, are expected to considerably reduce the individual opportunities to move outside the home. As physical activity (PA) and sport participation significantly contribute to health, this study has two objectives. The objectives of this study are to assess changes in PA and well-being since the coronavirus outbreak in affected countries. Additionally, we will evaluate the impact of digital home-based exercise programs on PA as well as physical and mental health outcomes.

Method: A multinational network trial will be conducted with three planned phases (A, B, and C). Part A consists of administering a structured survey. It investigates changes in PA levels and health during the coronavirus outbreak and measures the preferences of the participants regarding online training programs. Part B is a two-armed randomized-controlled trial. Participants assigned to the intervention group (IG) will complete a digital 4-week home exercise training (live streaming via internet) guided by the survey results on content and time of program. The control group (CG) will not receive the program. Part C is 4-week access of both CG and IG to a digital archive of pre-recorded workouts from Part B. Similar to Part A, questionnaires will be used in both Part B and C to estimate the effects of exercise on measures of mental and physical health.

Results and Discussion: The ASAP project will provide valuable insights into the importance of PA during a global pandemic. Our initial survey is the first to determine how governmental confinement measures impact bodily and mental well-being. Based on the results, the intervention studies will be unique to address health problems potentially arising from losses in PA. If proven effective, the newly developed telehealth programs could become a significant and easy-to-distribute factor in combating PA decreases. Results of the study may hence guide policy makers on methods to maintain PA and health when being forced to restrict public life.

Study Register: DRKS00021273.

COVID-19 - does exercise prescription and maximal oxygen uptake (VO2 max) have a role in risk-stratifying patients?

As the UK shields 'high risk' patients and enforces social distancing measures, patients will be at risk of significantly reducing physical activity levels. We explore the evidence base for COVID-19-specific recommendations and exercise interventions to 'precondition' patients prior to infection and appraise the role of maximal oxygen uptake (VO2 max) as a risk-stratifying triage tool. We conclude that structured exercise programmes can be used to maintain physical activity levels and prevent deconditioning and that VO2 max has the potential to be used as a clinically relevant triage tool during the COVID-19 outbreak.

Benefits of Exercise on Influenza or Pneumonia in Older Adults: A Systematic Review

A coronavirus pandemic has recently become one of the greatest threats the world is facing. Older adults are under a high risk of infection because of weaker immune systems. Therefore, the purpose of this review is to summarize the recent scientific evidence that outlines the effects of exercise on influenza or pneumonia in older adults. An electronic literature search was conducted using the WEB OF SCIENCE, SCIENCEDIRECT and GOOGLE SCHOLAR databases using the following keywords, "Exercise," "Older adult," "Influenza," and "Pneumonia." Any randomized control trials, cross-sectional and observational studies that related to this topic were all included. Twenty studies met the eligibility criteria for this review. Thirteen randomized control trials investigated the effects of exercise on the immune responses to influenza or pneumonia vaccination: seven trials employed moderate aerobic exercise, three employed resistance exercise, and the remaining three used Asian martial arts or special home-based exercises. Five cross-sectional and two observational studies examined the associations between exercise/physical condition and influenza/pneumonia. Most of the current studies suggested that prolonged moderate aerobic exercise may help to reduce the risk of influenza-related infection and improve the immune responses to influenza or pneumonia vaccination in older adults. In addition, training in traditional Asian martial arts was also found to be beneficial. Future research should focus on the different effects of moderate and vigorous exercise on influenza-related diseases.