Table 7 Quotes about factors of grandparents’ physical activity and sedentary behavior on the interpersonal (characteristics of the grandchild(ren)) level

Number of grandchild(ren) to take care of

Quote 20 (Grandparent 33, ♀, 62 years): “The more grandchildren that are with us and who can play the board game, the more it will be played, of course. And the more fun it is.”

Sex of the grandchild(ren)

Quote 21 (Grandparent 37, ♂, 57 years): “The difference between the grandsons and the granddaughters is striking. We have a bigger garden and then… Yes, the grandsons are more willing to come along when I say ‘let’s go and collect the eggs from the chickens’ and so on. They’re more easily involved. They help more in the garden,… And then the granddaughters will do more sedentary activities, that’s what my wife does, a bit of tinkering and reading to them and so on.”

Age-related physical/motor development

Quote 22 (Grandparent 6, ♂, 58 years): “The way these smaller grandchildren play determines whether you’re very active or actually sedentary. Such small children, they have large play mats, they have all their toys on it and they’re always playing in the same two square meters. You sit there, you observe them, you help them, I take dozens of photos every time. So you just sit there and do nothing.”

Quote 23 (Grandparent 29, ♀, 54 years): “I do notice that as the grandchildren get older, we tend to watch movies on TV more often and that’s less active. When they’re younger, we used to go by bike and go feeding the ducks or the chickens or go on the swing, and that changes when they become older.”

Quote 24 (Grandparent 19, ♀, 69 years): “You can’t play football with little grandchildren. They’re very active but their movements are completely different. I’m used to going to the gym, to the shop, to cook, to do the grocery shopping and those are all things that you can’t do if you’re with a small grandchild like that.”

Quote 25 (Grandparent 11, ♀, 56 years): “I play more on the floor with the grandchildren, which is something I’d not normally do. That’s very pleasant, but I notice as I get older that it becomes a little more difficult.”

Quote 26 (Grandparent 34, ♀, 61 years): “We don’t actually go for many walks because the youngest grandchild is only two and a half and the oldest is nine.”

Age-related cognitive development

Quote 27 (Grandparent 33, ♀, 62 years): “The older the grandchildren get, the more they ask to play board games. From the moment they can read and count and all those things, we noticed that these kinds of activities increase. This is also linked to more sedentary behavior for sure.”

Health of the grandchild(ren)

Quote 28 (Grandparent 26, ♀, 61 years): “In case my grandson is ill, you don’t do much with him. Then he mainly needs his rest and then it’s more about nursing and medication and so on. You have to adapt your activities to what he needs: sleeping, providing medication, changing his diaper; so it’s physically different.”

Character, mood and interests of the grandchild(ren)

Quote 29 (Grandparent 17, ♀, 69 years): “When my grandson is here, I have the feeling that I’ve not been sitting still all day. It really requires running after him the whole day. Of course it’s very tiring. He makes me jump on the trampoline, walking over walls, and everything. So as a grandmother, I’m always involved in his game. But the other grandchild is, like I said, totally different, and thus much calmer.”

Quote 30 (Grandparent 11, ♀, 56 years): “If my granddaughter is being a bit moody, I’ll more easily say ‘let’s go for a walk’ or we’ll go to see the ducks. Then the child’s behavior sometimes encourages me to be active, and sometimes to be sedentary.”

Quote 31 (Grandparent 9, ♂, 62 years): “The tablets are turned on when the grandchildren are tired. Then we put on the iPad and watch it together or we turn on the TV and watch it together, and we lie down in the chair together.”

Quote 32 (Grandparent 20, ♀, 61 years): “The twin grandchildren like to read books; you can consider that as a moment of rest for yourself. They walk around and go get new books. I’m also lucky that they like to dance; so I put on a CD, like K3 (which is a Flemish girls band for children). Then they both start to dance. I like to dance with them, so that’s also physical activity.”

Quote 33 (Grandparent 37, ♂, 57 years): “When the grandchildren are around, we make sure that we always do some activities, like going to the zoo, taking a day trip. Or to a bigger playground, where they can enjoy playing.”

New experiences of the grandchild(ren)

Quote 34 (Grandparent 24, ♀, 55 years): “Many of these games, such as ‘Red light, Green light’, things like that, were learned at camp, so then you apply it at home. So indeed, you’re very active, and it is actually quite nice. The strange thing is that while you’re busy, you don’t realize it, it’s only when they’re gone in the evening that you say ‘Oh I’m tired’.”

Grandchild(ren)’s planned activities

Quote 35 (Grandparent 33, ♀, 62 years): “Another thing that affects our ability to be physically active is the grandchildren’s activities on Wednesdays. The oldest ones already have after-school activities, they’ve sports activities and then we’re drivers for those grandchildren and that interrupts your afternoon, because they have to be there on time, they have to be dressed, you have to go and get them.”

Nap of the grandchild(ren)

Quote 36 (Grandparent 10, ♂, 59 years): “Especially small grandchildren sleep a lot. That limits your freedom of movement. You do have the baby monitor so you can work a bit. But, for example, you can’t work in the garden in the meantime. You always have to be stand-by, so the activities are more sedentary when you have small children, who still sleep a lot.”