There has been a recent shift from studying the effects of each movement behaviour separately to simultaneously examining the effects of all movement behaviours that occur in a 24-hour day (1–6). This paradigm was motivated by the findings that sleep, sedentary behaviour (SB), and physical activity are associated with health (7, 8) and that the amounts of time spent in these behaviours are perfectly collinear parts of the 24-hour day – more time spent in one movement behaviour inevitably leads to less time spent in the remaining ones. The new paradigm has been widely accepted by researchers and international and national public health authorities. The World Health Organization and several countries have issued 24-hour movement guidelines (9–18). According to the novel 24-hour movement guidelines, adults should, for example, limit their SB to no more than eight hours per day, accumulate at least 150 minutes of moderate-to-vigorous physical activity (MVPA) per week, and sleep seven to nine hours a day (12).
Studies among children and youth have suggested that adhering to recommendations for a higher number of individual movement behaviours (e.g. for 3 vs for 2, or for 2 vs for 1) is associated with greater health benefits (19, 20). However, for adult populations, such evidence is scarce. Given that the 24-hour movement guidelines for adults have recently been issued in several countries, from a public health perspective it is important to explore whether meeting more movement behaviour guidelines is associated with greater benefits. According to the framework for Viable Integrative Research in Time-Use Epidemiology (VIRTUE), such associations should be explored for a range of health outcomes (2). For the purpose of this study, we selected stress and self-rated health as outcome variables, as they have often been explored in relation to movement behaviours.
Stress is commonly defined as a “physical, mental, or emotional strain or tension” (21). It can be understood as individual’s response to events that they experience as threatening to their well-being or overwhelming (22). Although it is a natural response, prolonged stress can have negative effects on health (23). Chronic stress can substantially alter nervous, cardiovascular, endocrine, and immune functioning, and it is associated with various chronic diseases, including coronary heart disease, stroke, depression, and anxiety (24–28). Frequent experience of stress is a pervasive issue: every third adult globally reports experiencing a lot of stress (29). Furthermore, stress is associated with movement behaviours (30–32). The relationship is considered to be bidirectional, with stress as a predictor of engagement in movement behaviours and engagement in movement behaviours as a predictor of stress. In particular, high stress seems to be associated with low levels of MVPA (32) and short sleep (31). Findings on the association between SB and stress are inconsistent (33).
Self-rated health is one of the most widely used measures in epidemiological studies (34). It represents one’s subjective evaluation of their own overall health status. Self-rated health is a strong predictor of mortality risk (35), and it was found to be consistent with the objective general health status (36). Findings from the World Health Survey suggested that the global prevalence of poor self-rated health is around 10% (37). Previous studies have found that high MVPA (38), low SB (39) and adequate sleep duration (40) are associated with better self-rated health. These relationships are also likely to be bidirectional (41).
Very few studies examined the associations of the 24-hour movement behaviour composition with stress and self-rated health (7, 8, 42). Previous studies that assessed combinations of movement behaviours in relation to stress have shown mixed findings. For example, Onodera et al. (43) found that reallocating time from SB to MVPA is associated with less stress. Oftedal et al. (44, 45) found a favourable association with stress for an overall ‘healthy’ combination of movement behaviours and dietary habits. Some studies did not find a significant association between stress and movement behaviour compositions (46, 47). Furthermore, studies on the association between movement behaviour composition and self-rated health suggested a positive role of MVPA (48) and light-intensity physical activity (47). However, evidence on the association of adherence to the 24-hour movement guidelines with self-rated health and stress is scarce.
Therefore, the aim of this study was to explore the associations of meeting the 24-hour movement guidelines with self-rated health and the frequency of stress among adults. We focused on exploring whether the likelihood of favourable stress and self-rated health outcomes increases with the number of movement guidelines met. We hypothesised that meeting the combined 24-hour movement guidelines (i.e. recommendations for sleep, SB, and MVPA) is associated with better self-rated health and lower frequency of experiencing stress. We also hypothesised that adhering to a higher number of individual recommendations is favourably associated with self-rated health and stress.