In my usual “answer-a-question-with-another-question” style, let me ask you: what’s the best tool to fix a car – a wrench or a screwdriver?
They’re both tools and they each have their intended function. Sooner or later, you’ll need to use both – and a whole lot more. Some tools can serve multiple purposes… you can pound a nail with a wrench, for example, but if you do this too often, you ruin the ability of the wrench to perform its intended function.
Back to the realm of fitness, what’s better: a low carb diet or a low fat diet? Free weights or machines? Yoga or powerlifting?
All are just tools, right?
Now if I was put in a corner and HAD to choose between resistance training and traditional ‘cardio,’ I’d go with the weights all the way… it’s the more versatile tool between the two. You can get all the ‘cardio’ you need DURING a resistance workout by manipulating the training intensity and rest intervals.