Thanks Rob. So you're saying just working out / weight lifting is enough of a "cardio" workout?
Precisely what am saying mate. The most important factor in any fat loss program, is the maintenance of lean tissue, a well constructed strength training program is the only reputable way do that. Fat loss on the other hand is almost purely a matter of diet, simply decrease your calories by 500 below your maintenance level daily, and you will lose up to a pound of fat a week (without any need for additional wear and tear on your joints and connective tissues). Moreover, one pound of fat (3500 calories of energy) can fuel the body for up to 10 or more hours of continuous steady state activity, making steady state activity simply an ineffective method for fat loss.
Back in the late 90s, I had the pleasure of speaking with was HIT pioneer and former Mr universe Mike Mentzer, in one of my first consultations i had with him, i brought up the topic of "cardio", he barked...
"There is whats known as the SAID principle (Specific adaptations of Imposed demands), which means the body adapts in a specific fashion to specific demands, so if you want to be an endurance athlete, train like one, and likewise for bodybuilding, powerlifting or whatever. But for the Bodybuilder, aerobic activity is not just a waste of time, its counterproductive!"
Evolution also rings true here, most experts agree, that we as a species did not always have food/energy so readily available (which is still a major concern in many countries today), that being true, it only stands to reason that we evolved as a species that PRESERVED ENERGY as best as possible, not as one that RECKLESSLY SQUANDERS energy. Back to bodybuilding, stimulate the body with intense training (a form of intense physical stress), then rest, recover and grow! The energy you would lose in a so-called "cardio" workout, well be better used for recovery. This is what Mike Mentzer meant when he referred to "THE PROTECTION OF THE LIMITED", as we all posses a limited recovery ability.
Best of luck