BACKGROUND: Objectively measured levels of physical activity (PA) in patients undergoing Roux-en-Y Gastric Bypass (RYGB) surgery remain essentially unchanged from before to one year after surgery. Effects from RYGB on objectively measured levels of PA among women undergoing RYGB and appurtenant children beyond one year post-surgery are unknown. The aim of the present study was to objectively assess longitudinal changes in PA and sedentary time (ST), among women undergoing RYGB and appurtenant children, from three months before to nine and 48 months after maternal surgery.

METHODS: Thirty women undergoing RYGB and 40 children provided anthropometric measures during home visits and valid accelerometer assessed (Actigraph GT3X+) PA data, three months before and nine and 48 months after maternal RYGB surgery.

RESULTS: Women undergoing RYGB decreased time spent in moderate to vigorous PA (MVPA) with 2.0 min/day (p = 0.65) and increased ST with 14.4 min/day (p = 0.35), whereas their children decreased time spent in MVPA with 13.2 min/day (p = 0.04) and increased ST with 110.5 min/day (p < 0.001), from three months before to 48 months after maternal surgery. Twenty, 27 and 33% of women, and 60, 68 and 35% of children reached current PA guidelines three months before and nine and 48 months after maternal RYGB, respectively.

CONCLUSIONS: Objectively measured PA in women remains unchanged, while appurtenant children decrease time spent in MVPA and increase ST, from three months before through nine and 48 months after maternal RYGB. The majority of both women undergoing RYGB and children are insufficiently active 48 months after maternal RYGB.