Moderate exercise may prevent the development of severe forms of COVID-19, whereas high-intensity exercise may result in the opposite

Long-term impact of SARS-CoV-2 infection on cardiorespiratory fitness: a meta-analysis

Background

Despite surviving Coronavirus disease 2019 (COVID-19), its long-term impact is of concern. Low cardiorespiratory fitness is a strong predictor of all-cause mortality, and likely affected by multisystem impairments following COVID-19 infection. Accumulating evidence has identified the impact of COVID-19 on cardiorespiratory fitness level. However, the findings have been controversial. Conclusive evidence is still needed.

Objectives

This review aimed to systematically summarize and synthesize whether the SARS-CoV-2 infection diminishes cardiorespiratory fitness in COVID-19 survivors.

Design

The study design was a systematic review and meta-analysis.

Methods

A search was carried out using PubMed, CINAHL, Scopus, Embase and the Cochrane Library, together with reference lists (searching from their inception to January 2023). Observational studies investigating the impact of COVID-19 on outcomes relevant to cardiorespiratory fitness (i.e., peak oxygen uptake) were included. Weighted mean difference (WMD) and 95% confidence interval (CI) were used to identify a pooled effect estimate. Use of a random effects model was considered as the main method. Grading of Recommendation Assessment, Development and Evaluation approach was employed to determine the certainty of evidence. This meta-analysis was registered with PROSPERO (registration number: CRD42023393108).

Results

Seven eligible studies (4 cross-sectional, 2 cohort, and 1 case-control studies) involving 4,773 participants were included in this meta-analysis. A pooled effect estimates showed that patients in the surviving COVID-19 group had a significant reduction in peak oxygen uptake when compared to their counterparts in the non-COVID-19 group (WMD -6.70, 95%CI -9.34 to -4.06, low certainty). A subgroup analysis by age found that COVID-19 survivors in the young- to middle-aged and middle- to older-aged subgroups had significant reductions in peak oxygen uptake when compared to their counterparts in the non-COVID-19 group (WMD -5.31, 95%CI -7.69 to -2.94, low certainty; WMD -15.63, 95%CI -28.50 to -2.75, very low certainty, respectively). Subgroup analyses by symptom found that patients with moderate to severe symptoms in the surviving COVID-19 group had significantly lower peak oxygen uptake than their counterparts in the non-COVID-19 group (WMD -15.63, 95%CI -28.50 to -2.75, very low certainty).

Conclusion

The current meta-analysis concluded that patients in the COVID-19 survivors had poorer cardiorespiratory fitness than their counterparts in the non-COVID-19 group, but there is considerable uncertainty of evidence. Poorer cardiorespiratory fitness is likely to be more pronounced in COVID-19 survivors who are getting older and had severe symptoms, but it is uncertain whether such finding has a valuable in clinical context.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, CRD42023393108.

Exercise intensities modulate ACE2/MasR/eNOS pathway in male Wistar rat's lung

Specific exercise intensities could improve lung vascular function by increasing nitric oxide (NO). The ACE2/MasR/eNOS axis is one of the pathways facilitating NO synthesis. This study examines the effect of different intensities of aerobic training on the ACE2/MasR/eNOS axis and histology of lung muscular arteries. Male Wistar rats were used in this study and randomized into control and exercise groups receiving low-, moderate-, and high-intensity training. The training was conducted for 30 min daily, five times a week, for 8 weeks. We observed that different exercise intensities affect the ACE2/MasR/eNOS pathway differently. Compared to control, high-intensity aerobic exercise significantly increased ACE2, Mas receptor (MasR), and eNOS mRNA expressions (p < 0.01). Moderate-intensity exercise significantly increased MasR and eNOS mRNA expressions compared to the control (p < 0.05), and this intensity also increased ACE2 mRNA but not significantly. Low-intensity exercise increased ACE2, MasR, and eNOS mRNA expressions but not significantly. Low-, moderate-, or high-intensity exercises reduced the medial wall thickness of the lung muscular arteries but not significantly. In conclusion, high-intensity exercise may induce NO synthesis in the lung by increasing mRNA expression of ACE2, MasR, and eNOS without decreasing the medial wall thickness of the muscular artery. Thus, high-intensity exercise may be the optimal intensity to improve NO synthesis and vascular function in the lung.

Effect of Functional Electrical Stimulation on Muscle Mass, Fatigue, and Quality of Life in Older Patients With COVID-19: A Randomized Clinical Trial Study

OBJECTIVE

This study aimed to evaluate the effects of functional electrical stimulation (FES) on muscle strength, fatigue, muscle mass, and quality of life (QoL) in older patients with COVID-19.

METHODS

Older patients with COVID-19 were randomly divided into the following 2 groups: real FES (intervention group, n = 20) and sham FES (control group, n = 20). These patients received FES concurrent with the voluntary contraction of muscles for 10 consecutive sessions. Ultrasound imaging, pressure biofeedback, Chalder fatigue scale, and QoL were utilized to measure muscle mass, muscle strength, chronic fatigue, and QoL, respectively. Evaluations were performed at the beginning, immediately, and 1 month after the end of intervention.

RESULTS

All variables showed statistically significant improvement immediately and 1 month after the intervention in the real FES group (P < .05). However, the tibialis anterior muscle mass and fatigue significantly improved immediately after the intervention in the sham FES group. However, the tibialis anterior and rectus femoris muscles strength and rectus femoris muscle mass were not significantly changed immediately and 1 month after the intervention (P > .05). There were significant differences in muscle mass, physical fatigue, muscle strength, and QoL between groups with more efficacy of real FES (P < .05).

CONCLUSION

For this sample of patients, FES improved fatigue, muscle strength, muscle mass, and QoL in older adults with COVID-19.

Effects of physical activity on the severity of illness and mortality in COVID-19 patients: A systematic review and meta-analysis

Purpose: This systematic review and meta-analysis investigated the association between Physical activity (PA) before Coronavirus Disease 2019 (COVID-19) infection and the severity of illness and mortality in COVID-19 patients.

Methods: A comprehensive search was undertaken to identify retrospective and nonrandomized controlled trial studies comparing the severity and mortality of COVID-19 infection among COVID-19 patients who had previously reported their participation in PA with those who had not. The databases searched were PubMed, Cochrane Library, Scopus, Science Direct, EMBASE, OPENGREY.EU, and ClinicalTrials.gov. The risk of bias was assessed using the Newcastle-Ottawa Scale. A random-effects model was used for determining pairwise meta-analyses. The protocol was registered with PROSPERO (CRD42021262548).

Results: Eighteen studies met the inclusion criteria (5 cross-sectional, 12 cohort, and 1 case-control studies). All 1 618 680 subjects were adults. PA significantly decreased the risk of death in COVID-19 patients (odds ratio [OR] 0.34; 95% confidence interval [CI], 0.19–0.62; p < 0.001) and the risk of severe outcomes (OR 0.60; 95% CI, 0.48–0.76; p < 0.001). Subgroup analysis showed that PA for ≥150 min/wk at a moderate intensity or ≥75 min/wk at a vigorous intensity reduced the risks of severity and mortality. Vigorous PA reduced mortality risk, whereas moderate to vigorous PA reduced the risks of severity and mortality.

Conclusion: PA before infection might reduce severity and mortality in COVID-19 patients, especially PA ≥ 150 min/wk of moderate activity or ≥75 min/wk of vigorous activity. However, careful interpretations should be considered due to the difference in PA patterns and severity definitions among included studies. This finding implies that engaging in regular PA, even in different patterns, has beneficial effects on the severity and mortality of COVID-19 patients.