A pilot study of mindful walking training on physical activity and health outcomes among adults with inadequate activity.

INTRODUCTION

Mindful walking is a meditation practice that combines physical activity and mindfulness practice. Some mindful walking interventions expect four weeks of attendance (as compared with the traditional 8-week models of mindfulness-based interventions, or MBIs), a practice that could make MBIs more accessible to working-age adults. This study examined whether a 4-week mindful walking intervention increased physical activity and improved mental health outcomes.

METHODS

We conducted a randomized experiment among adults with inadequate physical activity (N = 38), whereby the intervention group received a four-week, one-hour-per-week mindful walking intervention and the control group received instructions to increase physical activity. Everyone in both groups received a wrist-worn step count device as participation incentive. Physical activity (as measured by the Rapid Assessment of Physical Activity questionnaire, RAPA) and other health outcomes were assessed with online surveys at baseline (T1), post-intervention (T2), and one month after the intervention (T3). Those mental health outcomes included perceived stress (Perceived Stress Scale), depression (Brief Edinburgh Depression Scale), and Mental Health Inventory (MHI). The primary outcome of device-measured step count was recorded at T1 and T2. Independent two-sample t-tests were used to compare the primary outcomes at T1. Generalized linear mixed models (GLMM) with a random intercept for each subject were used to compare the two groups on the primary outcomes at all time points. The independent variables in the model included a binary variable for group assignment (intervention vs. control), a 3-level categorical variable for time, and their interaction. Age, gender and race/ethnicity are used as covariates in the model. Estimated changes (either differences or ratios between outcomes at time points T1 and T2/T3) are reported to assess change within groups.

RESULTS

Both groups exhibited significant improvements in the RAPA measures of physical activity and depression. However, between-group differences were not statistically significant. There was no within-group or between-group difference on device-measured step count, though both groups yielded an average daily step count close to the recommended level of 8,000 steps per day for older adults. The intervention group exhibited a significant reduction in perceived stress, and this reduction was significantly greater than that of the control group at T2 (p = .025) although the difference was insignificant at T3. No significant difference in MHI was found.

DISCUSSION

While these adults with inadequate physical activity increased their physical activity, no significant between-group differences in physical activity were identified. Potential reasons for the lack of significant findings could be due to the ceiling effect (the step count device for everyone in both groups might have encouraged more activity in both groups), limited sample size and low-dose 4-week intervention used in this study. On the other hand, it is encouraging to see that this low-dose, short-duration 4-week intervention (as compared with those popular 8-week MBIs) achieved significantly greater stress reduction among the intervention group than among the control group, even though the between-group difference at one-month follow-up was statistically insignificant. Further studies with larger sample sizes and longer follow-up are needed to assess the possible benefits of these short-duration mindful walking interventions.