Zenandnow, great advice!! Weightloss is absolutely not all about cardio, cardio, cardio. I have done no scheduled cardio workouts (treadmill, cross trainer, etc.) and I have lost my 104lbs (in 7 months) purely from strength training. It's so much more difficult to recover you muscle mass afterwards. If you are able to I would absolutely incorporate weights/strength training into your workout. Muscle is much more efficient at burning calories. If you look at Fiddleman's posts in the fitness section he also talks about his experiences with cardio in the beginning vs his weight/strength training. No good personal trainer will have you injuring yourself. They will be coaching you and your form! I'm only half way through my journey and for my weightloss my skin still looks pretty OK. I attribute this to my weight/strength training and functional workouts!! There is life beyond pounding the treadmill for hours! Just find the balance that works for you.. Obviously if you want to be a runner.. Then you will do more cardio