Treadmill Incline

Since January 1st I have been hitting the treadmill daily and sticking to my 1200 calorie diet, from which I've seen results on the scale.

I know everyone talks about doing weight resistance training in addition. My question to all of you is if I'm running at an incline (2% incline today) aren't my legs getting some sort of resistance training? Same goes for running with 8 pound weights in my hands...aren't my arms getting some sort of resistance training during the run?

I love the results I'm seeing on the scale each morning (9 pounds in 21 days), so I hate to give up my 40 minute daily run on the treadmill.

Thanks everyone!