Discussion
COLD
Overall, results from this pair of studies are consistent with hypotheses that this intervention has the potential to promote increased hiking frequency, as well as other aspects of health and well-being that have been linked with outdoor physical activity. In Study 2, winter traction cleats were provided to the intervention group to address barriers reported in the first study, in which engagement in the intervention was relatively low, but links between hiking frequency and well-being outcomes suggested the potential of the intervention with greater uptake. Engagement was higher in the second study, and there were significant intervention effects on hiking frequency and evidence of improvements in sleep in the intervention group by post-intervention. While effects on stress did not reach statistical significance, results were in the expected direction.Addressing the main barrier to intervention engagement reported in Study 1 seemed to improve intervention uptake in Study 2, yet just under half of the participants assigned to the intervention group still did not engage in any challenge hikes. In Study 2, a lack of winter hiking equipment or comfort hiking outdoors in the winter were no longer mentioned as common barriers, but some new barriers emerged as themes, including challenges with traveling to the hiking locations and also health-related barriers such as testing positive for COVID-19. The former is an important barrier to note, given the goal to make interventions like this accessible to all individuals. The majority of participants in both of these studies were white and middle-to-upper-income. Addressing barriers such as the financial and time costs of traveling to hiking locations across the region may broaden accessibility of this intervention, including to those from lower-income households. The organizer of this regional challenge has since debuted an Urban Hiking Treks series, which features a set of walks that can be completed outdoors within a shorter radius around Buffalo, New York, perhaps offering one way to address this barrier among those who live in and around this city.Health-related barriers are also notable and may have been especially problematic during Winter 2022 with the emergence and rapid escalation of the Omicron variant of COVID-19. In examining public records, we noted a greater prevalence of COVID-19 cases in Winter 2022 versus 2021 in the region under study, as well as a colder, snowier winter in 2022. For example, in aggregating daily weather data from the National Oceanic and Atmospheric Administration from January-March 2021 and 2022 across the 5 counties of the Western New York region, we found that the average low temperature was 5 degrees colder in 2022 compared to 2021, and that the total inches of snowfall was 69.0 inches in 2022 versus 33.6 in 2021. In addition, within the study data, the percent of individuals reporting a recent positive COVID-19 test was higher in Study 2 versus Study 1. It is notable that engagement in the intervention increased from Winter 2021 to 2022, even with these potential health and weather-related barriers. Participants randomized to the intervention group in both studies had control over whether and when they hiked, offering more flexibility than many existing studies testing effects of outdoor physical activity, in which study participants visit the researchers to participate in assigned physical activity. While this flexibility may have affected implementation, it is also a strength in terms of the ecological validity of this intervention and its potential for sustainability in the context of participants’ everyday lives.The present studies have implications beyond the COVID-19 context. The hiking interventions were implemented in the winter in the Western New York region of the United States, which is known for cold and snowy weather. While pandemics may represent one context in which physical activity decreases, sedentary activity increases, and associated health outcomes worsen, winter is another time in which individuals may be less likely to engage in physical activity outdoors. Continuing to build upon the present study findings offers potential to promote outdoor physical activity and associated health benefits during times in which these activities tend to decline. Given the demonstrated health benefits of outdoor physical activity (e.g., [Limitations of the present studies included the small samples, which as mentioned above, were fairly homogeneous demographically. These limitations impact the generalizability of the present findings, and it is not yet known whether results would be consistent (or weaker or stronger) in larger, more diverse samples. Initial findings across these two studies suggest that increasing uptake of this intervention in the present samples is linked with increased hiking, as well as other well-being benefits. While effects were generally in the expected direction across outcomes measured in Study 2, some did not reach statistical significance, with the small samples potentially constraining the ability to detect effects. Future research can examine whether effects are augmented when recruiting larger, more diverse samples and continuing to address reported barriers to improve uptake. Previous reviews have noted the potential for links between outdoor recreation and health benefits to be even greater among low-income populations, further highlighting the potential of bringing a feasible, acceptable version of this intervention to populations at disproportionate risk for negative health outcomes [Overall, the present studies demonstrate potential of continued research in this area. Efforts to address additional reported barriers can elucidate whether these efforts further increase uptake of this intervention and augment health and well-being benefits. The current findings support the potential of such efforts, with statistically significant intervention effects on hiking frequency in Study 2 and corresponding evidence of positive impacts on aspects of well-being, including sleep duration and quality. Future research examining the feasibility and acceptability of this intervention approach and its effects on daily activities and various aspects of health and well-being in a larger, more diverse sample is warranted, as this research has the potential to promote physical activity and well-being at times when physical activity rates are low.