works both ways Tama...

if a skinny little wimp like me

If you are indeed skinny, then your own weight, which is the weight your muscles would move, is smaller. This means that the increase in raw strength is smaller than it is for heavier people (or for people who do more than their own weight of strength) - and likely, so is the increase in muscle weight / size. On the other hand, the increase in physical resistance and heart and lung condition can be ever greater as it would be for heavier people. Although, if you jog, you probably don't have too much of that need either...