A systematic observation of moderate-to-vigorous physical activity levels in Australian natural blue space locations

Research has shown that blue space (i.e. water-based environments) can be good for physical and mental health, with one possible reason being that people are physically active when visiting blue space environments. However, little is known about how active people are when visiting blue space. We used the System for Observing Physical Activity and Recreation in Natural Areas to systematically record whether people were active while visiting eight different blue space locations in Australia. We first calculated the proportion of people who were moderately or vigorously active at each location and then conducted a series of linear regression models to determine which demographic and environmental factors predicted higher activity levels. We identified that 44% of people visiting blue space locations were active. However, there were significant interactions between both age and gender, and type of blue space. Males (β = −0.25, p = 0.018) and females (β = −0.26, p ≤ 0.001) were less active at built-up riverfronts than coastal beaches. Females were also less active at inland beaches (β = −0.15, p = 0.013) and watering holes (β = −0.20, p = 0.011) compared with coastal beaches. Children (β = 0.16, p = 0.006) and adolescents, however, were more active at inland beaches (β = 0.32, p ≤ 0.001) than coastal beaches. These results are important to consider when making decisions around access to, and infrastructure within, blue space environments, as different blue space environments influence human behaviour differently for different people.