rating of the difficulty of their breathing .
REFERENCES
Shaw , K ., Butcher , S ., Ko , J ., Zello , G ., & Chilibeck , P . ( 2021 ). Wearing of cloth or disposable surgical face masks has no effect on vigorous exercise performance in healthy individuals . International Journal of Environmental Research and Public Health . 17:1-9 . Chandrasekaran , B ., and Fernandes , S . ( 2020 ). Exercise with face masks : Are we handling a devil ’ s sword ? - A physiological hypothesis . Medical Hypotheses . 144 :
Assoc . Prof Mike Climstein , PhD FASMF FACSM FAAESS AEP Dr Climstein is one of Australia ’ s leading Accredited Exercise Physiologists . He is a faculty member in Clinical Exercise Physiology , Sport & Exercise Science at Southern Cross University ( Gold Coast ). such as wearing a mask , one option is to make an assumption on what size of effect we would expect to detect a difference . The authors did exactly this : they made an assumption about how much peak power output would be reduced by ‘ mild hypoxia ” and they assumed that it would be a 5 % reduction . They then concluded that if mild hypoxia was present , with their sample size it should be enough to detect it 95 % of the time . So , if they ran their experiment 20 times they should detect mild hypoxia if it was present 19 times out of 20 . So far , this is acceptable . However , their finding should then read ‘ mild hypoxia not present when performing a progressive exercise test on a Monark cycle ’, as opposed to ‘ Wearing a face mask has no effect on vigorous exercise ’. From the conservative standpoint that I take with regards scientific results , the title of the paper , although more exciting , over-reports the results of the study .
Further concerns about their study design revolve around the number of significant figures reported for result values in their data . I will focus on one value they recorded , as an example , namely blood oxygen saturation (%) This value is reported to the nearest 1 %, with approximate mean values of 96 % for no mask or a surgical mask and 95 % for a cloth mask . If the authors are recording data accurately to more significant figures , it should be reported more precisely . It looks like the values are approximately the same because the data is rounded in their results table , but looking at their graph it appears at every single mean power output value from 0 to 100 %, that the arterial oxygen saturation is lower when wearing a mask . Visual inspection would therefore imply that there may be a difference when wearing a mask . I can go into this in more detail , however in concise terms for the purposes of this Research Review I would be very cautious concluding there is no effect on exercise from wearing a mask .
The effect is similar for RPE ; the mean RPE
is clearly higher for the majority of peak power output % values ( from their graph ) when wearing a mask than without . This may not be statistically significant ; however , I believe that the statistical analysis and assumptions the authors have selected are not enough to rule out this effect – which is what they have done in their interpretation of results . This could be a purely psychological effect , but it at least establishes that I am perhaps not alone in
perceiving a greater rate of exertion .
Another caution is that the study authors used Bonferroni analyses , which are susceptible to false negatives , namely not detecting differences when they exist ( exactly what is being claimed ).
Therefore , in my interpretation , the study authors ’ conclusion of no differences from wearing a mask does not agree with the literature they quote in their own manuscript and is not well supported by their own data analysis . Regardless , I would like to be clear that people should still wear a mask during exercise when mandated by state regulations : doing so might save the life of an elderly or unfit fellow patron working out in the gym , someone simply walking past while an exerciser goes for a jog , or anyone who later interacts with an infected person .
This was a very timely study with good methodology , however , it would have been appropriate for the investigators to also use the Rating of Perceived Dyspnea ( RPD ) scale , as this is specific to shortness of breath ( SOB , one of my favourite medical abbreviations ) and breathlessness . Most exercise enthusiasts and personal trainers will be familiar with Borg ’ s rating of perceived exertion scale . This scale was developed by Borg and is widely used with any patients who have respiratory disorders like chronic obstructive pulmonary disease and asthma . The scale is from 0 ( nothing at all ) to 10 ( maximal ) and pertains to the participants
Dr Joe Walsh , PhD Joe is an exercise science researcher . He has worked in a number of large international research teams with study findings presented around the world . In addition to working in the university sector , he is a director of Fitness Clinic Five Dock and Sport Science Institute .
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