Snacktivity™ to promote physical activity during pregnancy: feasibility randomised controlled trial

Abstract Background Guidelines recommend that pregnant women complete at least 150 min of moderate-intensity physical activity per week. However, it is estimated that only 32% of pregnant women adhere to this guideline early in their pregnancy, with this rate decreasing to 12% as pregnancy progresses. The updated physical activity guidelines encourage all durations of physical activity and no longer stipulates that activity needs to be performed in bouts of 10 min or more. Consequently, the short bout Snacktivity™ intervention was adapted for pregnant women and a feasibility randomised controlled trial was conducted. Methods Pregnant women were recruited at fetal antenatal dating scan appointments at 10 + 0 and 16 + 0 weeks gestation) or via posters on social media. Participants were enrolled in the study from randomisation (~ 16-weeks gestation) until 36-weeks gestation (~ 18 week duration). Participants were individually randomised (2:1 ratio) to an mHealth Snacktivity™ physical activity intervention plus standard antenatal care group, or to a standard antenatal care group (comparator). The assessment of outcomes occurred at baseline, 26- and 36-weeks gestation. The primary outcome was the feasibility and acceptability (recruitment rate, adherence Snacktivity™ and attrition) of the trial and Snacktivity™ intervention to promote physical activity according to traffic light stop-go criteria. Accelerometer-measured physical activity, gestational weight gain and psychological health outcomes were assessed via exploratory analyses. Results Ninety-six participants were recruited in six months (against target of 90) and 14/96 (14.6%) participants did not provide follow-up data (green stop-go thresholds). Snacktivity™ adherence met the red criteria as 13/54 (24.1%) participants completed on average ≥ 4 activity snacks per/day. Adjusted mean differences in total minutes of physical activity (16.0, 95%CI -12 to 43.9), gestation weight gain (-0.8 kg, 95%CI, -2.6 to 1.0) and depression scores (0.6, 95%CI: -2.3 to 1.0) favoured the Snacktivity™ intervention group at follow-up. Conclusions With modifications to increase adherence, the Snacktivity™ intervention has potential to be a feasible and acceptable approach to promoting physical activity during pregnancy. Trial registration ISRCTN60667435.