Background:

This study examined potential parenting-related mediators of children’s physical activity and dietary behavior change in the Healthy Dads, Healthy Kids (HDHK) community program.

Methods:

A randomized controlled trial was conducted with 45 overweight/obese (mean [SD] age = 39.8 [5.4] years; BMI = 32.4 [3.8]) fathers and their children (n = 77; 58% boys; mean [SD] age = 7.7 [2.5] years). Families were randomized to either the HDHK program or wait-list control group. The program involved 7 sessions. Fathers and their children were assessed at baseline and at 14 weeks for physical activity (pedometery) and core food intake (Questionnaire). Fathers’ lifestyle-related parenting practices included; self-efficacy, beliefs, modeling, logistic support, rules, cophysical activity, shared mealtime frequency and intentions.

Results:

Significant intervention effects were found for cophysical activity and modeling physical activity. Cophysical activity mediated children’s physical activity in the intervention (‘mediated effect,’ AB = 653, 95% CI = 4–2050) and was responsible for 59.5% of the intervention effect. Fathers’ beliefs mediated children’s percent energy from core foods (AB = 1.51, 95% CI = 0.05–5.55) and accounted for 72.9% of the intervention effect.

Conclusions:

Participation in the HDHK program positively impacted on fathers’ cophysical activity with their child and beliefs about healthy eating which mediated changes in children’s diet and physical activity behaviors.