Sedentary behaviour, physical activity, and sleep among office workers during the COVID-19 pandemic: a comparison of Brazil and Sweden

Since the coronavirus disease (COVID-19) outbreak in 2019, a considerable literature addressing effects of the pandemic on physical behaviours has appeared [1‐4]. Most of these studies have compiled information from a general population facing the challenges of shifting to working either from home (WFH) or in a hybrid set-up, i.e., working with a mix of days WFH and working at the office (WAO). The main findings in these reviews [1‐4] are similar to those in an online survey study by Trabelsi et al. [5], showing for a large international population that daily time spent in physical activity (PA) decreased and sitting time increased during the COVID-19 pandemic. Similarly, a review by Ráthonyi et al. [6] showed that physical behaviours of office workers were affected by restrictions during the pandemic in the direction of decreased PA, increased sedentary behaviour (SED) and increased sleeping time.

Even before the pandemic, office workers spent most of their day in SED, both during working and non-working hours, and they moved for less than 10% (i.e., about 100 min) of the day [7, 8]. High levels of SED and low levels of PA have been associated with detrimental health effects, including increased risks of developing chronic non-communicable diseases (e.g., type 2 diabetes, overweight, obesity, metabolic syndrome, cancer and cardiovascular diseases) [9‐11]. Some studies have shown that the harmful effects on health of extensive time spent in SED can be counteracted or mitigated if more time is spent in vigorous PA [11, 12]. In addition, a sleep duration of 7 to 8 hours per night is positively associated with health outcomes, and both too much and too little sleep may lead to health problems [13]. However, daily behaviours are inherently co-dependent and constrained because they share time within a finite 24-hour window. More time can be spent in one behaviour only at the cost of reducing time on one or more other behaviours, so that the fixed total of 24 hours, or 100%, is maintained [14, 15].

The changes in physical behaviours during the COVID-19 pandemic likely differed between countries due to different social restrictions adopted in order to slow down the transmission of the virus [16, 17]. Thus, the severity of restrictions has varied between countries, for instance regarding the distance people could travel from their homes, and the allowances for outdoor activity [18]. In contrast to many other countries implementing quite restricted and mandatory measures, the authorities in Brazil and Sweden largely relied on recommendations and voluntary measures, as implemented through individual responsibility. Thus, during the pandemic, many Swedish workers had a formal opportunity to choose WFH or WAO, even if WFH was recommended [19].

Brazil and Sweden thus appear similar in the extent of restrictions. The two countries do, however, differ in terms of socioeconomic status, culture, work environment, and the extent of physical inactivity [20, 21]. Prior to the COVID-19 pandemic, WFH was not common in Brazil (prevalence of 1 to 5%; International Labour Organization [22]) and the only legislation present was related to teleworking (article 75 of the law n° 13.467 of 2017), which does not deal with WFH. In contrast, remote work was already common in Sweden (prevalence of 20%) and it was regulated before the pandemic [23]. Thus, Brazilian office workers appeared to have fewer opportunities for choosing where to work during the pandemic (i.e., choose between WFH and WAO) compared to Swedes [19, 24]. Brazilians in general also have lower socioeconomic status, and are more sedentary and less physically active than Swedes [20, 21]. Therefore, comparing effects of the pandemic on physical behaviours of Brazilian and Swedish office workers would shed light on the extent to which behaviours were different in countries with the same level of restrictions but different demographic and social characteristics.

Most studies investigating the physical behaviour of office workers during the COVID-19 pandemic have been based on self-reported measures [1, 2, 6]. However, studies have shown that self-reported data may suffer from bias [25, 26], and that the extent of bias may be related to the status of the respondents [27, 28]. To come around the limitations associated with self-reports, data on time spent in different physical behaviours need to be assessed using wearable sensors, such as accelerometers, allowing accurate assessment of physical behaviours around the clock for several days [29, 30].

A 24-hour objective assessment of time-use allows a comprehensive understanding of physical behaviours in occupational as well as non-occupational contexts, and it also provides a basis for understanding of how behaviours interact, and how they together may influence health outcomes [15, 31]. Additionally, evidence of 24-hour behaviours allows for the formulation of valid guidelines for physical behaviours [31, 32], which can effectively support strategies to prevent sedentary lifestyles and promote better health. The importance of addressing behaviours in a 24-hour perspective is also reflected in recent guidelines, such as The Canadian 24-hour movement guidelines for adults [33].

To our knowledge, detailed data are lacking on 24-hour time-use compositions of SED, PA and sleep of office workers from different countries during the pandemic, measured using accelerometers. Understanding 24-hour time-use compositions of physical behaviours during the pandemic in countries with less severe social restrictions, while acknowledging differences in demography and socioeconomics, may assist future post-pandemic recommendations, including guidelines for WFH. It may even contribute to a better preparedness in the event of a future pandemic scenario. Therefore, the aim of this study was to document and compare 24-hour time-use compositions of sedentary behaviour, physical activity and time-in-bed (as a proxy for sleep) among Brazilian and Swedish office workers at working and non-working days during the COVID-19 pandemic, on the basis of recordings by wearable sensors.

This study documented, during working and non-working days, the 24-hour time-use compositions of sedentary behaviour, physical activity and time-in-bed (i.e., proxy for sleep) of Brazilian and Swedish office workers during the COVID-19 pandemic and also examined to which extent these compositions differed between countries. To date, no other study has compared the 24-hour time-use compositions of office workers measured using wearable sensors (i.e., accelerometers) between countries with similar restriction policies, but with acknowledged differences in demographic and socioeconomics. Therefore, examining the compositions of time spent during work for these workers is important to support post-pandemic interventions and recommendations, including guidelines for WFH. Likely a substantial proportion of workers will continue to work from home or in a hybrid model (i.e., both WFH and WAO) after the pandemic [47].

Compared with Swedes, Brazilian workers spend more TIB relative to time awake on working days, more time in SED (both short bouts and long bouts) relative to in non-SED, more time SED in long bouts relative to short bouts, and more time in LPA relative to MVPA (Table 3). Similar results were found during non-working days, the only exception being that the relative proportions of TIB were similar for workers in both countries (Table 3). Sensitivity analysis of data only from working days spent at home showed similar results to the analysis of working days in general, however with a slightly smaller effect size. The results indicate that differences between countries may be explained only to a minor extent by the opportunity in Sweden to work at the office [19], and that other factors also contributed to the differences between the physical behaviours of Brazilian and Swedish workers found in this study [20, 21].

Previous studies of work during the pandemic corroborate our findings, in reporting that office workers spend extensive amount of time sedentary during working and non-working days [6, 24] irrespective of the workplace, i.e. whether it is at home or at the office [19, 48]. Even before the COVID-19 pandemic, extensive sedentariness was an issue among office workers [8, 49]. The literature indicates that SED has increased during the pandemic compared to before [1‐4, 6], which may have been an effect of physical distancing and isolation imposed by the pandemic. Both distancing and isolation, to an extent depending on the country and when the pandemic occurred [18], diminished or eliminated the autonomy of people to leave their homes and engage in regular activities (e.g., school, work, fitness training), as well as utilize community resources (e.g., parks, playgrounds, walking trails). As a result, strategies to contain the virus may have increased the prevalence of physical inactivity worldwide, reducing the already low levels of physical activity in some occupational groups [21, 50]. The detrimental effect of the pandemic may have been larger in low- and middle-income countries, such as Brazil, compared with high-income countries, such as Sweden [20, 50]. Since, however, Brazilian office workers do not have a very low income, it appears that additional factors may have contributed to the difference in physical behaviours between Brazil and Sweden. This could, for example, be a low awareness among the Brazilian workers of the benefits of physical activity for health and well-being [51]. Therefore, this indicates that Brazilian office workers may be in particular need of preventive actions to reduce sedentary behaviour and increase physical activity.

Physical activity, sedentary behaviours and sleep have been investigated independent of one another for a long time, but recent research highlights the importance of addressing behaviours in a 24-hour perspective [14, 15, 32], as it provides a better understanding of how behaviours interact and how they may influence health outcomes together [31]. The importance of addressing behaviours in a 24-hour perspective is also reflected in the Canadian 24-hour movement guidelines [33]. This guideline for adults aged 18–64 years recommends at the most 8 sedentary hours per day, and recommends breaking up sitting as often as possible, as well as spending at least 150 min per week in moderate-to-vigorous physical activity, along with several hours of light activity and/or standing, and 7 to 9 hours per night of good-quality sleep [33]. In general, the population samples in our study did not achieve a balanced 24-hour time-use according to the Canadian guidelines. When examining the behaviours of each individual participant during working days, none of the Brazilian workers and only 13 Swedish workers achieved a 24-hour time-use that fulfilled the Canadian guidelines. On non-working days, four Brazilian workers and 34 Swedish workers met the guidelines. This may deserve particular attention in policy planning [31, 33]. When checking each component of the guideline, the recommendation to limit SED to 8 hours or less per day was the least likely to be achieved by most workers in our sample. A majority of Brazilian and Swedish workers spent more than 10 hours per day being sedentary and most of this time was accumulated in long bouts (cf. Fig. 2). Spending excessive amount of time in long-bout SED corresponds to less variation in physical behaviours [41], which may increase health risks [11, 12]. We observed that, on average, Brazilian workers had more SED in bouts ≥30 min, both during working and non-working days (478 and 359 min) compared to Swedish workers (367 and 251 min). A possible explanation for this finding may be a difference in the homes and workplaces of Brazilian and Swedish workers. As WFH in Brazil was not common before the pandemic, the sudden change in location caused by the pandemic may have caught many of them unprepared. Thus, they had to adapt their homes in the best way possible to carry out their activities. This may have led to workers sitting at their – adapted – workstations for most of the day, not allowing much standing or walking.

Excessive sedentary time, as found in this study, has been associated with detrimental health effects, development of non-communicable diseases and early mortality [9‐12]. Until now, there is no exact evidence regarding the time in SED that will lead to a health risk. However, studies indicate that this threshold can be 8 hours or more per day (i.e., about 33% of the day) [10, 12], which is also reflected in the Canadian guidelines [33]. Thus, our results, at least for those workers who spend excessive time in SED (Fig. 2), suggest that strategies should be developed to encourage office workers to be more active. Additionally, interventions implemented in the workplace in the past, such as standing desks for meetings and spatial reallocation of dust bins or printers, may not be useful in the home environment [49]. Therefore, future studies should evaluate the ergonomic conditions when WFH, in order to develop new initiatives to meet recommendations while WFH [47]. In addition, to protect workers’ health, companies should investigate whether the living place fulfil the minimum necessary conditions for work activities to be performed safely.

Specific needs for some workers are suggested by the considerable heterogeneity in the physical behaviour data among workers in both groups (cf. Fig. 2). It appears that some workers may have perceived the pandemic as an opportunity to be more physically active during working and non-working days because work could be structured in a more flexible schedule. In contrast, some may have faced barriers to physical activity introduced by the pandemic, i.e., limited access to public places and closure of sports facilities, thus having fewer possibilities to exercise. This suggests that some workers need additional support, either from their employer or the government through labour and public policies, to deal with conditions when WFH and doing hybrid work.

Despite Brazil and Sweden implementing similar restriction policies during the COVID-19, the 24-hour time-use compositions of physical behaviours differed considerably between Brazilian and Swedish office workers. During both working and non-working days, Brazilian office workers were more sedentary and less active than Swedish workers; while time spent in bed was similar among the workers in both countries. Many workers, in particular in Brazil, spent more than half of the 24-hour working day sedentary, predominantly in uninterrupted bouts longer than 30 min. Whether the differences between Brazil and Sweden relate to work tasks, work conditions, or socioeconomic status being different, to restrictions being perceived or interpreted differently, or to differences that were present even before the pandemic is not clear. Given the disease risks associated with extensive sitting, we encourage public health policy-makers to consider our findings when developing future work-from-home guidelines.