Originally Posted by JKAWB
what if you are a reather skinny guy and don't want to lose weight but gain a little, is it worth it? all i do is run, i never lift weights.
If you are looking to gain mass, it would not be my recommendation. I would recommend lifting weights 3-5 days a week supplemented with moderate cardio after lifting - like 20-30 mins of elliptical machine. Each session should focus on 1-2 body parts. You should also check your diet out, for skinny guys (hard gainers), I would recommend equal protein and carbs, and no unnecessary fat. That is the 20k foot view anyway : )
If you never lift really, I would recommend getting with a trainer (who looks the part) for nutrition and a program. Lifting can be a lot of fun and you can see great results with a good program. Conversely, if you just go in there and wing-it, you may end up working hard and not achieving anything and/or hurting yourself.
There is also a tremendous amount of information online, but there is also a lot of misinformation - so weeding through and tailoring it is a serious time commitment. Most good trainers have a lot figured out already.