I put on a stone in weight for rugby from 12'7 to 13'10, quite a lot of which i think was muscle.

I did it in the off season and then found wen i did a jog that my time was appalling compared 2 wat i wud hav expected.

I think its kind of like the first time my body has ran with a stone of extra weight and it is a shock 2 the system, can ne1 confirm this?