Holding a heavy baby to settle

Hi,

We have a 4 month old who is starting to get on the heavier side.

He’s right at the stage where he still needs help to settle but seems to only fall asleep when we’re holding him and standing. Which at 7kg+ starts to get overwhelming after a while. The body is sore.

Any sense of sitting (rocking chair or couch) and he cries bloody murder so we stand again to make him stop crying. From what I’ve read, it seems babies may have an inbuilt response where they feel safer when the parents are standing.

Has anyone had a similar experience and found any tricks (outside a baby carrier) which makes getting them to sleep a bit easier than always standing?