Reduced level of physical activity during COVID-19 pandemic is associated with depression and anxiety levels: an internet-based survey

The coronavirus disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) raised several questions about public health, economic, and political crisis [1].

After the initial outbreak, which occurred in December 2019 in Wuhan, China [2], the virus rapidly spread across China and reached Europe and both Americas [3, 4] and finally across the world. The first recorded case in Latin America was in São Paulo, Brazil, on February 26, 2020 [5]. In the following month (March 2020), several measures to control and contain the virus spread were taken by government institutions and health authorities in Brazil [6]. In the second half of March, schools and parks were closed and, commercial activities and non-essential services were suspended [6]. All these measures were taken in order to implement physical distancing among people to contain the spread of SARS-CoV-2, which has been considered a fundamental method to contain the virus spread [7]. As a consequence, these measurements of social distancing also may negatively impact the daily physical activity of the population [7‐13].

Physical inactivity has been considered a global pandemic since 2012 [14], and it is estimated that 28% of the world population (1.4 billion people) remain physically inactive [15]. This scenario is extremely worrying because physical inactivity is one of the leading causes of cardiovascular diseases, diabetes, obesity, and premature mortality in the world [15‐17]. Therefore, if the population’s physical activity levels further decrease during this physical distancing period, it will be an even greater challenge for public health agencies, as this condition may further complicate the pandemic scenario since the presence of diabetes, obesity, hypertension, and other comorbidities associated with physical inactivity can worsen the COVID-19 prognosis [7, 17].

In addition, physical distancing/isolation measures and the continuous spread of the pandemic are also expected to influence the mental health of the population [18]. Excessive information, uncertainties regarding the future and one’s health, frustration due to interruption of projects, boredom, reduction of family income, as well as a political and economic crisis, can generate or exacerbate symptoms of depression and anxiety levels [19, 20]. These problems associated with low levels of physical activity may also negatively impact mental health.

This scenario of physical inactivity and physical distancing/isolation measures may exacerbate existing health issues and social inequities for the female population [21, 22]. Descriptive studies reveal that women have a significantly higher risk than men for developing anxiety and depression disorders [23‐25]. Moreover, some studies have reported that women consistently have lower physical activity levels than men [26, 27]. However, the effects of physical distancing on physical activity levels between the different sexes are still unknown. It is reasonable to assume that the impact on physical activity levels would be greater in women, as they accumulate professional tasks with household tasks such as taking care of children now the schools are closed [28].

Descriptive data of the participants age, body mass, height and BMI were presented in Table 1. For between sexes comparisons, male participants of the present study presented significantly higher values of age, body mass, height and BMI (Table 1).

The number of participants and the percentage values according to BMI, the adoption time of social distancing, the adhesion level to social distancing, family income, physical activity levels adopted pre-pandemic period and adopted at current period, the change in physical activity levels in relation to those prior to social distancing, depression and anxiety symptons were presented in Table 2. In the whole sample, most participants were eutrophic, adopted physical distancing measures for 76 to 90 days, maintained partial restriction, leaving only for essential non-work activities, received more than 11 minimum wages, were very active, did not alter their physical activity level during pandemic period, presented mild depression symptoms and no anxiety disorder. The male sample differs from the whole sample because most participants were overweight, adopted physical distancing measures for 61 to 75 days and presented minimal depression symptoms. The female sample differs from the whole sample because most participants were active and have mild anxiety disorder (Table 2).

The association between mood state (depression and anxiety level) with the dependent variables was studied and there were significant associations between depression level (PHQ-9) and family monthly income [the higher adjusted residual was 7.2 for PHQ-9 classified as 4 (severe depression) and family income classified as 0 (less than 1 minimum wage)], level of restriction adopted during the pandemic period [the higher adjusted residual was 4.4 for PHQ-9 classified as 0 (minimal depression) and restriction level classified as 3 (not taking any measures of social distancing)], current IPAQ (the higher adjusted residual was 5.2 for PHQ-9 classified as 0 (minimal depression) and IPAQ level classified as 4 (very active), and Δ IPAQ (the higher adjusted residual was 5.3 for PHQ-9 classified as 0 (minimal depression) and Δ IPAQ classified as 0 (do not change the physical activity level), but not regarding the period for which social distancing measures were adopted. These data were analyzed using the Chi-square test, and the results are shown in Table 3.

There were significant associations between anxiety level (GAD7) and family monthly income (the higher adjusted residual was 5.0 for GAD-7 classified as 3 (severe anxiety disorder) and family income classified as 0 (less than 1 minimum wage), level of restriction adopted during the COVID-19 pandemic period (the higher adjusted residual was 2.8 for GAD-7 classified as 0 (no anxiety disorder) and restriction level classified as 3 (not taking any measures of social distancing), current IPAQ (the higher adjusted residual was 3.1 for GAD-7 classified as 0 (no anxiety disorder) and IPAQ level classified as 4 (very active), and Δ IPAQ (the higher adjusted residual was 3.4 for GAD-7 classified as 0 (no anxiety disorder) and Δ IPAQ level classified as 0 (do not change the physical activity level), but not regarding the period which social distancing measures were adopted. These data were analyzed using the Chi-square test, and the results are shown in Table 4.

Age differences regarding each anxiety level (GAD-7) were investigated via the Kruskal Wallis test. The results also showed a significant difference between the age of the different anxiety groups (N (3) = 176.4; p < 0.001). The age of the responders who had no anxiety disorder [42 (30) years old] was significantly higher than that of those who were mild anxiety [35 (15)] years old), which was also higher than the age of those who presented severe anxiety disorder [31.5 (13) years old].

There were significant association between sex (male or female) and BMI [the category that present the largest adjusted residuals (10.0 for males) was the category 3 (overweight)], the time of adoption restriction measurements [the category that present the largest adjusted residuals (3.9 for males) was the category 0 (less than 30 days)], the level of restriction adopted during the pandemic [the category that present the largest adjusted residuals (6.8 for males) was the category 3 (not taking any measures of social distancing)], current IPAQ values [the category that present the largest adjusted residuals (4.7 for males) was the category 4 (very active)], pre-pandemic IPAQ values [the category that present the largest adjusted residuals (4.6 for males) was the category 4 (very active)], Δ IPAQ [the category that present the largest adjusted residuals (− 2.4 for males) was the category 0 (decrease the physical activity level)], PHQ-9 score [the category that present the largest adjusted residuals (9.0 for males) was the category 0 (minimal depression)], and GAD-7 score [the category that present the largest adjusted residuals (7.5 for males) was the category 0 (no anxiety disorder)]. There were no significant association between sex (male or female) and family monthly income observed. These data were analyzed using the Chi-square test, and the results are shown in Table 5.

The main findings from the present study were: (i) the physical activity level adopted during the period of social distancing was significantly lower than that prior to this period, (ii) about 30% of the respondents presented moderate or severe symptoms of depression, and around 23.3% showed moderate or severe symptoms of anxiety during the social distancing period, (iii) the depression and anxiety scores were significantly associated, (iv) low levels of physical activity, low family monthly income and the participants’ age were associated with higher incidences of anxiety and depression, (v) there was more frequency of individuals than the expected who did not alter their physical activity level after the adoption of social distancing experiencing lower levels of depression and anxiety and, (vi) there was a higher frequency of men than of women who were very active, who did not change their physical activity level during the social distancing period and who had no symptoms of depression and anxiety.

The level of physical activity was significantly reduced during the social distancing period. Prior to the COVID-19 pandemic period, 69% of the volunteers (83% male and 46% female) were classified as very active, and during the social distancing period, this percentage dropped to 39% (50% male and 31% female). In Italy, were more strict rules of social distancing were adopted, including lockdown, an important reduction of physical activity was also observed [37]. To be classified as a very active person, it is necessary to perform at least 30 min of vigorous activity 5 times a week (or 20 min of vigorous activity 3 times a week plus 30 min of moderate activity 5 times a week) (IPAQ) [31]. This physical activity level has been associated with several healthcare benefits, including a lower risk of cardiovascular morbidity and mortality [38]. On the other hand, a lower physical activity level due to sustained social distancing potentially increases the risk of damaging the immune, respiratory, cardiovascular, musculoskeletal systems as well as compromising mental health [7]. This known damage from low physical activity can be especially harmful during this pandemic period. Although the SARS-CoV-2 usually first compromises the functioning of the lungs, it can also infect almost all major organs in the body [39]. Therefore superior cardiorespiratory conditioning should also help to combat the disease. Strong respiratory muscles and aerobic conditioning may help individuals who develop COVID-19 and require ventilator support, mainly during the ventilator weaning process [7]. Regarding the sex difference for physical activity, the results showed that the men presented higher physical activity levels, mainly in very activity domain, which also was found by Oyeyemi et al. [40]. Indeed, during the pandemic, men and women presented a decrease in physical activity levels; however, the difference between sex remain. Prior to the pandemic period, 9.5% of the participants were classified as insufficiently active (A and B) or inactive people and this number increased to 23% after the COVID-19 pandemic. There was a 147% increase in insufficiently active (A and B) or inactive people (males increased 190%, and inactive females increased 129%). This result is concerning because physical inactivity was classified by the World Health Organization (WHO) [41] as the fourth leading risk factor for global mortality, and there is recent evidence suggesting that a sedentary lifestyle is independently associated with cardiovascular diseases [42].

Another worrying result found in the present study concerned the incidences of symptoms related to depression and anxiety. Thirty percent of the total sample (20% male and 34% female) presented moderate or severe depression symptoms, and 23% of the total sample (15% male and 27% female) presented symptoms of moderate or severe anxiety. It is interesting to note that there is also a significant association between the presence of anxiety and depression symptoms, as has also been previously demonstrated that approximately 50% of people who present mood health disorder meet criteria for both depression and anxiety [43, 44]. Cao et al. [45] and Gao et al. [46] also found similar percentages for cases of anxiety (22.6 and 22.4%, respectively) for a Chinese sample of both sexes. On the other hand, Choi et al. [47] demonstrated that 19% suffered from depression, and 14% from anxiety in a cross-sectional study conducted in Hong Kong. Puccinelli et al. [48] demonstrated in a paper presenting preliminary results that 22.8% of the Brazilians and 7% of the Swiss presented moderate or severe depression symptons. The same criteria for depression and anxiety were used in the above studies (PHQ-9 score ≥ 10 and GAD-7 score ≥ 10). In addition to the COVID-19 pandemic, Brazil’s president, Jair Bolsonaro, continues to discourage physical distancing measures along with the use of face masks, contrary to the recommendations of health organizations [49]. This has led to an increased sense of insecurity and anxiety amongst the Brazilian population regarding the COVID-19 disease [50]. Moreover, the political and economic instability that the country is undergoing may also be contributing to the high incidences of depression and anxiety. Beyond the pandemic, according to WHO, the prevalence of depression and anxiety is highest than world prevalence (5.8 and 9.3%, respectively while world prevalence is 4.4 and 3.6%, respectively) [51]. As such, Brazil has one of the world highest prevalence of depression and anxiety.

Indeed, there is a significant association between both anxiety and depression and physical activity. Thre are a higher frequency than the expected of very active people presenting minimum depression symptoms and no anxiety disorder.

In the current study, the importance of physical activity related to mental health, the difference in physical activity levels between the pre-pandemic and physical distancing (current period) was also assessed. Those who did not alter their level of activity, and therefore managed to remain active in some way, reported a higher frequency of lower depression and anxiety symptoms. These findings reinforce the importance to find ways to increase physical activity level. In this context, home-based exercise programs and stimuli to interrupt physical inactivity and sedentary behaviour, resulting from the necessary confinement policies to contain the spread of SARS-CoV-2 could be a feasible option, mainly when the most Brazilian cities parks, gym and sport clubs are closed. There are some useful tips for Home-Based Physical Activity suggested by Ricci et al. [52], Souza et al. [53] and by Viana & de Lira [54], such as taking active short breaks, walking, following online exercise classes, playing with children or guiding the elderly to stay active.

One of the factors associated with PHQ-9 and GAD-7 scores are the level of physical distancing level adopted by participants. Participants who did not adhere to physical distancing recommendations presented a higher frequency than the expected of minimal depression symptoms and no anxiety disorders, suggesting that physical distancing affected mental health. Another factor studied was the family monthly income. A significant result to note was that there was a higher frequency than the expected of individuals who receive less than one minimum wage (which corresponds to less than 200 American dollars per month) presenting severe depression (adjusted residuals 7.2) or anxiety (adjusted residuals 5.0). This situation is very worrying because the necessary physical distancing measures not only have an impact on health but also can result in a devastating threat to economy, which may reduce a family’s income even further. The unemployment situation and the lack of prospects of returning to work are other factors that can have a negative impact on mental health [46, 55]. In a previous systematic review, Vindegaard & Eriksen Benros [56] also pointed out the importance of steady family income to preserve mental health. Interestingly enough, the period of time for which an individual is in social distancing has not impacted mental health. It is possible that there is a ceiling effect, that is, social distancing has a negative impact on depression or anxiety symptoms, but that more time of isolation does not further worsen these symptoms.

Finally, there is also a significant difference between age groups, according to the PHQ-9 and GAD-7 questionnaire. Younger respondents presented more symptoms of depression than the older ones. In relation to anxiety levels, younger respondents were also found to be more anxious than older ones. Gao et al. [46] also evaluated people between 18 to 85 years old, and the authors also found a higher incidence of depression among those between 21 and 30 years of age. One possible reason may be that increased anxiety, and depression symptoms among young people are due to their higher social media exposition, one of the main channels used for updating COVID-19 information [46, 57]. However, considering age as a risk factor for depression and anxiety provided inconsistent data, given that the elderly (over 60 years of age) also presented high levels of these mental illnesses [55].

Regarding sex differences in relation to depression and anxiety levels, the results showed that women presented a higher frequency of depression and anxiety. This had already been demonstrated in studies of Chinese and Italian populations [55, 58]. Furthermore, according to WHO, women present a higher prevalence of mood disorders than men in all world regions [51]. There is also a higher frequency of male participants who were very physically active and a higher frequency of males who did not change their physical activity level during the social distancing period. There was a higher frequency of male participants who did not adhere to the social distancing recommendations, which may be a contributing factor to their lower frequency of anxiety and depression. However, the design of the present study design does not allow us to affirm if there is a causal relationship between these factors.

As a cross-sectional study, a limitation of the present study is the lack of anxiety and depression assessment before the pandemic period, moreover it is not possible to establish causal relationships between variables, as they were measured at the same time. In addition, it was also necessary for volunteers to remember when they were answering the questionnaire (June 2020) what was their physical activity level before the pandemic period (March 2020). Another possible bias is concerning the sample evaluated. Despite having1,853 respondents, the study was also disseminated via e-mail and social networks, which may not be representative of the entire population of the country, but only of people who have access to the internet and that use social networks. Finally, in June 2020, there were a series of government guidelines for people not to leave their homes. The restaurants, parks, sports clubs and shops were all closed. It is possible that when the volunteers were asked about the level of restriction they were adopting, they became embarrassed to answer the truth if they were not following the government’s recommendations.

Considering the dramatic change in lifestyle linked to physical inactivity and all non-communicable diseases associated with this condition, such as diabetes, cardiovascular disease and obesity as well as the significant association between physical inactivity and mental diseases, it is clear that people during this social distancing period are becoming much more physically and mentally vulnerable, which affects their ability to combat a possible COVID-19 infection. Therefore, physical activity programs should be encouraged, given that they respect the required social distancing to contain the spread of SARS-CoV-2.