The current strategy to prevent the community spread of COVID-19 includes social distancing, hand washing, and the use of face masks. The wearing of face masks provides a physical barrier to reduce the risk of transmission of virus particles until a vaccine is available. As sporting organizations are working out the proper return to play protocols that may include the wearing of face masks during training and competition, here are some things to consider. In a recent randomized trial provided by researchers from the University of Leipzig, they examined the cardiopulmonary exercise capacity of 12 healthy males who participated in an incremental cycling test to voluntary exhaustion.
The Facemask Performance Study
Simply stated, the study was looking to identify how wearing a face mask affects heart and lung capacity during high-intensity or maximal exertion training. The males were randomly placed into one of three groups: one group wearing the N95 mask, one group wearing surgical masks, and one group not wearing a mask. Each participant completed the test three times with a minimum of 48 hours between each test. A baseline of respiratory function was obtained and after each test, both objective and subjective data were gathered. The objective data included a participant’s heart rate, cardiac output, stroke volume, maximum oxygen uptake (VO2max), and metabolic parameters. At the end of the cycling test, additional tests were administered to each participant such as peak flow and forced expiratory volume (FEV), to further measure lung function. The subjective data included fatigue levels, breathing resistance difficulty, and other questions that identified the comfort of the mask and how it made the athlete feel.
The study reports that “both masks have a marked negative impact on exercise parameters such as maximum power output (Pmax) and the maximum oxygen uptake (VO2max/kg). The N95 masks show consistently more pronounced negative effects compared to surgical masks. Both masks significantly reduce pulmonary parameters at rest (FVC, FEV1, PEF) and at maximum load (VE, BF, TV).” There was no difference noted in the cardiac output or metabolic parameters but with the lung capacity being reduced, there was a reduction in the body’s ability to oxygenate the blood. This was observed by the reduction of the arterio-venous oxygen content (avDO2). “Therefore, the primary effect of the face masks on physical performance in healthy individuals is driven by the reduction of pulmonary function. In addition, the auxiliary breathing muscles have been described to induce an additional afferent drive which can contribute to an increase of the fatigue effect.”
Athlete Performance While Wearing A Mask
These findings indicate that while wearing a facemask is helping to prevent the community spread of Covid-19, performance will most likely be impaired in healthy individuals performing high-intensity or maximal exertion training. Athletes who already deal with pulmonary issues such as asthma may be at risk of more than impaired performances. More research will be needed to determine how this applies to athletes who have pulmonary issues and if these results will continue, or if participants will be able to adapt to the wearing of facing masks in the long term.
High-altitude athlete training
This may lead to the question, is mask-wearing like high-altitude training? There is a greater amount of oxygen at sea level. As altitude elevates, oxygen supply decreases. That is why you may find yourself light-headed as you head to higher elevations to participate in sport, especially if you live at sea level. High-altitude training has been used to help endurance athletes improve their performance by increasing their body’s ability to take in oxygen. This is done by the body increasing the number of red blood cells to transport the needed oxygen to the body while living and training at higher altitudes where less oxygen is available. It also takes the body 1-3 days to acclimate to higher elevations.
High-performance athletes training at lower altitudes have tried using masks to see if they can replicate the benefits of high-altitude training through intermittent hypoxic training (IHT). “This involves the user to be subjected to brief exposures, typically 1–2 hours, of simulated high-altitude conditions to elicit a reduction in PO2 below normal levels using a mask". This method of training has not supported by research, so the carryover into wearing a face mask to improve VO2 max and performance is not supported at this time.
So where does that leave coaches and athletes who are being asked to train with face masks during this pandemic? This is where the risks and benefits need to be determined. The risk of exposure vs the benefit of performance.
The best option would be to train outdoors, without a mask, using social distancing. If you have to train indoors and/or face masks are required, then athletes and coaches will need to make modifications to their training schedules. By understanding an athlete’s response to training (internal load) will most likely be at a higher level for the same amount of training (external load) provided, training durations and intensities should be decreased, with increased recovery times, at least initially. During competition, athletes may need to be subbed on a more regular basis. Using subjective training metrics, such as rate of perceived exertion (internal load) and identifying fatigue levels (perceptual well-being), coaches can have a better understanding of how their training load is affecting their athletes within the new training circumstances of wearing face masks. Is this something they can train through? More research is needed before that can be determined.
To learn more about internal load, perceptual wellbeing, and how to apply these tools within your team, our course How to Monitor High-performing Athletes will provide you with the needed understanding to implement these tools efficiently and effectively.