ABSTRACT
The main objective of this randomized controlled trial was to analyze the acute effects of a nitrate-based nutritional formula on peripheral oxygen saturation (SpO(2)), patient-reported outcomes, and safety indices in patients with acute COVID-19 infection. The participants completing the protocol for the trial (n = 71) were allocated in a double-blind design to receive either a multicomponent nutritional formula (containing 1200 mg of potassium nitrate, 200 mg of magnesium, 50 mg of zinc, and 1000 mg of citric acid), or a placebo (2.5 g of inulin) during a 72-h monitoring period. All participants were requested to take an intervention (four capsules;weight of each capsule was similar to 2.5 g) every 4 h during the intervention period. A two-way mixed model ANOVA with repeated measures revealed a significant difference in SpO(2) between interventions (P = 0.007). As many as 30 out of 38 patients (78.9%) receiving nitrate-based nutritional formula, who all started the treatment with SpO(2) <= 95%, finished the intervention with SpO(2) of at least 95% at 72-h follow-up, whereas in the placebo group, 13 patients out of 33 (39.4%) finished the trial with SpO(2) of at least 95% (P < 0.05). The hospital admission rate after the 72-h follow-up was 21.1% in patients receiving nitrate-based formula compared to 33.3% in the placebo group (P = 0.25). The nitrate-based formula might be recognized as a potent strategy to tackle hypoxemia and concomitant features of the COVID-19 pandemic. In conclusion, it appears that the novel nitrated-based nutritional formulation described here was able to improve oxygen saturation and clinical outcomes in COVID-19 patients. Although the exact mechanism of action remains unknown, the nitrate-based formula might be recognized as a potent, safe, and convenient strategy to tackle hypoxemia and concomitant features of the COVID-19 pandemic.
ABSTRACT
Athletes' lifestyles have been dramatically affected by the coronavirus disease 2019 (COVID-19) pandemic. Since COVID-19 primarily affects the respiratory system and to a lesser degree the cardiovascular system, the goal of this study was to examine the effects of COVID-19-caused detraining on cardiorespiratory fitness (CRF) of recently recovered volleyball athletes. Sixteen experienced volleyball athletes (age 24 +/- 4.5 years) who were recently diagnosed and recovered from a COVID-19 infection volunteered to participate in this study and were tested for CRF and spirometry. Given that participants had only mild symptoms of infection, the primary focus of this study was on the effects of detraining on CRF. On average, the time to exhaustion was 9.4 +/- 1.4 min. VE, VCO<sub>2</sub>, RER and oxygen pulse increased, heart rate exceeded 90% of predicted values, and peak VO<sub>2</sub> values were typical for this level of athlete (44.1 +/- 3.4 mL/kg). Pulmonary function reflected in FVC, FEV1/FVC and MVV values were well above 80% of predicted values for each of the participants while electrocardiography revealed no ischemia, arrythmias or conduction and repolarization abnormalities were found in the tested subjects. Therefore, it can be concluded that participants experienced typical consequences of detraining. Due to a lack of CRF data prior to COVID-19 infection, we were unable to estimate the magnitude detraining had on CRF. Complete CRF assessment after COVID-19 infection in athletes can be useful for screening of residual myocardial and/or respiratory system damage for safe return-to-play decisions.