I have a 30kg weighted vest which I use for bodyweight exercises like chins and dips. It's a fantastic training tool, but unless you're using it to overload a particular muscle group, it's probably not what you're looking for if your goal is to add size.
It sounds like you're wanting to just wear it while you're walking, which would make it more of a "systemic" exercise like a loaded carry. Although great for increasing overall strength, it's not an ideal mass building exercise.
If you were to try it, I'd keep the weight pretty low - even putting my full 30kg vest on is kinda challenging, and just leaving it on between sets gets pretty uncomfortable. I definitely wouldn't be setting off on a walk of any more than a couple of hundred metres with that sort of weight, but maybe 10kg might be OK.
I'd be interested to hear what results you get if you do try it.
It sounds like you're wanting to just wear it while you're walking, which would make it more of a "systemic" exercise like a loaded carry. Although great for increasing overall strength, it's not an ideal mass building exercise.
If you were to try it, I'd keep the weight pretty low - even putting my full 30kg vest on is kinda challenging, and just leaving it on between sets gets pretty uncomfortable. I definitely wouldn't be setting off on a walk of any more than a couple of hundred metres with that sort of weight, but maybe 10kg might be OK.
I'd be interested to hear what results you get if you do try it.