Which one is better: A jump-a-roo or a walker for building leg muscle strength?

I was also told that walkers are dangerous...is that true?

Both are fine if you are using it as a toy for enjoyment purposes (5-10 mins max a day) and not to put bub in it for a long time while you are doing something. Prolonged use can cause problems for your bub in walking. I saw it first hand a boy who was in a jolly jumper only walks on his toes now, very odd but that is what he was used to being in the jumper.
Walkers can be dangerous in that they can topple over in them and become stuck, you must supervise them at all times (of course) when using these toys.

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