Study limitations
hypoxia, pneumonia, muscle damage, ill
ACUTE INFECTION, HYPOXIA, PNEUMONIA
This study has some limitations that should be considered when interpreting the results. First, the sample size may not be large enough to confirm all observations, and future larger studies are warranted to examine potential differences among COVID‐19 variants or measure specific indicators of muscle damage. Second, functional outcomes were not assessed, and exercise‐induced hypoxia was not measured with cardiopulmonary exercise testing. Additionally, future studies could directly measure OxyHb from the GNM or assess other LE muscles in addition to the GNM. Third, physiologic changes were based on clinical observations, and histologic studies are needed to test angiogenesis or intracellular changes. Fourth, three patients in the CG recognized they had a sham device during the study, but they were not unblinded. Fifth, adherence to therapy and compliance were monitored by weekly phone calls, but no objective or device‐tracking method was used. Finally, baseline parameters were significantly different in pneumonia during acute infection, and oxygen at home, suggesting that the IG was more ill than the CG. Despite these limitations, we observed medium to large effect sizes for the benefit of E‐Stim, which was safe, easy to administer, and highly acceptable. Future efforts are needed to confirm or refute the initial compelling findings of this study.