Hi Mazzi
I'm 50 and weight 18 stone

took up bocking 3 odd years ago
I did loose weight but put it back on when I realised I could eat a lot more when bocking

But seriously the muscle you build up is much better for you than the fat it replaces and it is fun so you keep doing it
I would agree with Q that you should buy for the weight you are now as you will either grow of find that the extra muscle will mke you able to use them if you do loose weight
Jason
