Comparison of the Effect of Wearing Medical and Cloth Masks during Combined Exercise Training during the Period of Covid-19 on Maximum Oxygen Consumption in Non-Athletic Young Men

The COVID-19 pandemic has brought about unprecedented changes and alarmed many aspects of our existence. With the spread of the COVID-19 pandemic, most of the countries were quarantined, many people were in their homes due to social distancing and with the stress of facing an uncertain future and fear of death and loss of family members, and also economic problems caused by the disease caused psychological problems in many sections of the society (1). Wearing a mask is one of the non-pharmacological intervention measures that can be implemented effectively with minimal cost and without disrupting social activities (2). Also, one of the important strategies to prevent the spread of disease during sports activities in public environments, whether outdoors or in gyms, is to use a mask; In this regard, research results show that wearing a mask during sports can prevent the virus from spreading into the air and other people from contracting the corona virus (3, 4). The importance of wearing a mask went so far that the Centers for Disease Control and Prevention recommended that everyone wear a face mask for more than two years; especially when exercising indoors or when in public places (5). Despite the recommendation that people should use a face mask as a daily habit, wearing a mask during physical activity or sports may potentially have negative effects on the physiology. Therefore, masks should not be used during intense physical activity; because they lead to a decrease in the quality of breathing. Also, sweat can cause the mask to get wet faster, which makes breathing difficult and causes the growth of microorganisms (6, 7). Studies by Person et al. (2018) also show that wearing a mask in a 6-minute walking test has an effect on the heart rate of healthy adults (8). In this regard, the studies of Mapelley et al. (2021) showed that the increase in the feeling of shortness of breath with the use of a protective mask during exercise is more intense (9). The COVID-19 outbreak is having a profound impact on almost every aspect of life. Universal mask coverage is recommended as a means of controlling this disease. Regular exercise in a safe environment is an important strategy for healthy living in this crisis (1). Since gyms and public spaces may be sources of virus transmission, masking may become an integral part of physical activity (7). On the other hand, one of the main problems of using a mask is that it can prevent breathing. Also, the mask is gradually moistened and its resistance to incoming air increases (18). According to the mentioned materials, the purpose of this research is to compare the effect of eight weeks of combined training (aerobic and resistance) with a double-layered medical and fabric mask on maximal oxygen consumption (VO2max) of young non-athletes.

In this semi-experimental research with a pre-test-post-test design, among untrained young men with an age range of 35-25 years (average age 29.40 years, average height 175.30 cm, average weight 73.37 kg and body mass index 23.56 kg/m2) Tehran city, 40 participants were selected purposefully and randomly in four groups of 1-combined exercises with medical mask, 2-combined exercises with cloth mask, 3- combined exercises and 4- control. In this research, the shuttle run test was used to measure VO2max of the subjects; then, using the relevant formula, the estimation of the VO2max level of the subjects was calculated. The intervention phase was conducted in eight weeks and 3 sessions every week and every other day, the exercise groups performed a combined exercise program (aerobic-resistance training) using a medical mask, a cloth mask and without a mask. During this time, the control group was doing their daily activities. The obtained data were analyzed using paired sample t-test, analysis of covariance and post hoc Benferoni test. Statistical analysis was done with SPSS software version 24 at a significant level of P<0.05.

The results of the present study showed that combined exercise training significantly increases the VO2max of young men (P<0.01), but other results showed that the use of a medical mask and cloth mask decreases the VO2max compared to the training group without mask (P<0.01). Also, other results showed that there is no significant difference between cloth and medical masks in cardio-respiratory indices of young men (P<0.05).

The results of the present study showed that combined exercises both with the use of masks (medical and cloth mask) and alone (without the use of masks) significantly increased the VO2max of young men. In line with the current research, Jimeno-Almazán et al. (2023) showed that combined exercises increase the maximum oxygen consumption in patients who have recovered from Corona (24). Also, Prieto-Gonzalez et al. (2022) showed that combined training increases the VO2max in recreational endurance athletes (25). In addition, Khalifi et al. (2022) in a review study showed that combined exercises, compared to aerobic exercises and separate resistance exercises, cause more improvement in heart and sweat factors in middle-aged men (26). In examining the effect of mask on VO2max, the findings of our research showed that combined training with either fabric or medical mask reduces VO2max in young men compared to combined training without mask. In line with the findings of the present study, Driver et al. (2022), reported a decrease in VO2max during sports activity with a cloth mask (5). Umutlu et al. (2021) also reported a decrease in VO2max during exercise with a surgical mask (35). Although in these two studies, the acute effect of sports activity on VO2max was investigated, but probably the cumulative effects of training sessions are also related to the acute effect of training sessions, and the adaptations resulting from long-term training are also consistent with the training response on VO2max. Overall, the results of this research showed that the use of combined exercises with and without the use of a mask increased VO2max in non-athletic men. Also, the results of our research showed that using a mask during sports training reduces VO2max improvement compared to training without a sports mask.