Given the choice of one OR the other this isn’t even a question. The term “Cardio” as it is understood by the general public defines a bout of continuous cardiovascular exercise. This type of exercise is probably the least effective towards fat loss. The most effective type of routine is one that tells the body to preserve muscle mass during weight loss as well as depleting glycogen to the greatest degree. This is will put the body in the best possible state to lose body fat. Such a routine would include some type of strength training and high intensity interval training in combination as in congruent training or possibly a Crossfit type circuit routine. The key is to work as hard as you can. The metabolic stress caused by this type of training will increase the “afterburn” and force the body to adapt to the stimulus. The taller the perceived obstacle the quicker the adaptation.