This one takes the cake on obvious data disregarding that goes against the Fauci Narrative and they still come up with the conclusion masks are bad https://www.pnas.org/content/118/41/e2109111118
Cerebral and systemic physiological effects of wearing face masks in young adults and was published in the National Academy of Sciences was the title and this was in the first paragraph The effectiveness of this measure is currently being evaluated (1). This has led to ongoing discussions about possible adverse effects of mask wearing (e.g., dizziness, headaches, fainting), especially within the elderly, during long-term continuous mask usage and during physical activity. Chan et al. (2) reported that the arterial oxygenation (SpO2) did not change in elderly subjects after 1 h, while Law et al. (3) reported a significant effect on baseline cerebral hemodynamics and end-tidal carbon dioxide pressure (EtCO2) using functional MRI (fMRI) on middle-aged adults. No task-induced hemodynamic changes were found in this study. The bulk of these concerns arise due to potential hypercapnic effects of carbon dioxide rebreathing, which has not yet been evaluated in a thorough manner. It gets even better in the results section Small but significant changes in cerebral blood flow (CBF) and cerebral blood oxygen saturation (StO2) were detected for both mask types:
HOWEVER the writers then realize that they can't contradict Fauci too much and put this, EtCO2 showed a significant change but was discarded since the probe was affected by the air trapped within the mask.WAIT WHAT?!?!? When I read this I just shook my head and this because that tapped stagnant air is then re-bereaved by the mask wearer. It's like discarding a lit oven for a cake getting baked. Owe it baked itself, it had nothing to do with getting heated in a closed environment. Then again the past couple of years has proven that Fauci could say anything such as water doesn't get you wet and it's taken as stated fact, regardless of what the science says. In the discussion this was stated Our findings show that wearing a face mask leads to statistically significant changes in the cerebral hemodynamics and oxygenation (CBF and StO2) in healthy young subjects at rest, even for this first relatively short period of mask usage. However, the changes observed are minimal and are comparable to those typically observed during daily life (4). Within the limitations of the study, we cannot claim any concerns for mask use during daily life activities for healthy, young individuals. In order to draw a stronger conclusion, the duration of mask wearing could have been longer (harder to disentangle its effects from other physiological variables such as fatigue)
Meaning they admitted it causes issues but claim insignificant because they didn't test the subjects under stress, such as taking a multi-hour cognitive test. They intentionally excluded information that showed the masks trap CO2 and did the testing under less than stressful conditions. It's like comparing the Texas emissions test to the California one. Also they are disregarding the fact the trapped CO2 is causing the fatigue. The last sentence was, these populations may behave differently. Finally, the potential effect of mask wearing on individuals performing critical tasks needs to be studied with future investigations. Investigations of these effects are important for policy making in order to maintain quality of life for individuals and for minimizing risks in persons carrying out critical tasks. Basically admitting even with all the doctoring of the information that goes against the Fauci narrative, they still admit the masks cause problems.
This study from Sept 2021 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7919154/ also disregarded the effect of CO2 concentrations increasing caused by the masks. This review has examined the effects of various face masks and on the physiological and perceptual responses to physical activity. Although the body of literature directly evaluating this issue is evolving, for healthy individuals, the available data suggest that face masks, including N95 respirators, surgical masks, and cloth face masks, may increase dyspnea but have small and often difficult-to-detect effects on Wb, blood gases, and other physiological parameters during physical activity, even with heavy/maximal exercise. There is currently no evidence to suggest that wearing a face mask during exercise disproportionally hinders younger or older individuals, and significant sex-based differences are not expected. Depending on the severity of their underlying illness, individuals with cardiopulmonary disease are more likely than healthy individuals to experience increased exertional dyspnea with a face mask because of small increases in resistance and reinspiration of warmer and slightly enriched CO2 air. Such problems may serve as a basis for seeking exemptions from mask regulations, but the benefits of decreased dyspnea will need to be weighed against the risks of contracting the SARS-CoV-2 infection.
But as shown in the Harvard Room study, only a slight increase in CO2 concentrations causes a significant loss in cognitive ability.