Yoga vs weights for strenght training

AndreaWyland

Im on the journey of losing the last of my problem areas in terms of fat and have a really good routine. I do usually 6 days a week of working out doing something different each day (p90x dvds plyo, cardio x, core synergistic, and kenpo, stretch; Yoga dvd by Baron Baptiste; running; snowboarding and turbo jam punch kick and jam). I see new muscles and feel like there is muscle growth going on, I feel stronger, I can kick higher, do more stretches and yoga moves/more flexible, run farther, snowboard better, etc. I feel like Im on the right track. I was doing the p90x weight training videos as well, however, its really hard to fit those in with everything else Im doing and quite frankly I dont like those videos and they dont give me the cal results I want either. I dont have a lot of time to workout so I want something thats going to both burn cal and build strength/ give me long lean muscles.... my question:) Can I substitute weights for what Im doing above? Using my body as resistance (I do this a lot in the plyometrics with jumping and squats its super hard and in yoga as well as the core synergistic, pretty much all of them have some sort of body resistance workouts). Or is it imperative for keeping/building muscle ( I would strictly want long/lean muscle) to use weights? Would it be enough to do one day a week of full body weights or is that necessary? Im sore almost everyday still from the yoga, p90 videos and if I do a long run, which is why 1 day a week I take off of vigorous workout and maybe do a walk or something like that. Did that question in its roundabout way make sense? Any input would be fantastic. I looked it up online and find the info extremely conflicting. I would be happy with continuing on my path Im on and even adding more yoga, its healing quality is powerful:) instead of adding weights back in.