Repetition or resistance?

I agree, if you have a lot of weight to lose, or its your main priority, something like cardio is going to help you shed the pounds a lot faster. I would say maybe 1 or 2 sessions of strength training in conjunction with cardio is what you would need.

if you are just trying to lose weight then repetition is the way to go. :) but when you lose the weight withouit resistance then you will lose muscle tone. i.e. the part where you lost weight will sag. You should engage in a small amount of resistance training to keep your muscle tone.

My weight training instructor taught us that repetition is best for toning, and resistance is best for building muscle. If you're looking to bulk up, then do fewer repetitions at a higher weight. If you want to tone and build strength/endurance, do more repetitions at a lower weight. Find the max amount of weight that you can lift/pull/push in one repetition, and then do your repetitions (10-15 if for endurance/toning) at 8-10 lbs less than the max. Then you can gradually build up. If you have a hard time getting through repetitions, then lower the weight. If you go through it too easy, then raise it a few pounds. For weight loss, you're going to probably want to focus on toning. Best of luck!