If I want to lose fat quickly, should I do as much cardio as possible?

    Not unless you love it. Dropping calories, as opposed to burning the extra calories, is by far an easier method of reducing weight quickly. That said, do a little cardio for your health, and don't lose weight too fast, it will come back.
 Low-Intensity or High-Intensity Aerobic Exercise:  Which One's Right For Your Goal?

What is the difference between high and low-intensity exercise?

• High-intensity cardiovascular exercise (60 to 80 percent of V02 max. or 80 to 85 percent of your max. heart rate) burns more total calories in less time and more absolute fat calories than low-intensity exercise.

• Low-intensity cardiovascular exercise (40 to 50 percent of V02 max. or 60 to 65 percent of your max. heart rate) burns fewer total calories but a higher percentage of fat calories than high-intensity exercise, measured for the same amount of time.

• With the goal of body fat loss, higher-intensity exercise yields the same results as lower-intensity exercise, but in a shorter period of time.

Guidelines for proper cardiovascular intensity

• Beginner exercisers should work within 50 to 60 percent of their maximum heart rate.

• Once you become accustomed to an exercise intensity level, it is helpful to increase your workout intensity. Changing the intensity and/or duration of your aerobic workout every two weeks helps you avoid plateaus and continue to lose body fat.

Main thing

If your goal is body fat loss, higher-intensity exercise yields the same results as lower-intensity exercise, but in a shorter period of time. In order to keep the body in a revision phase, the mode and intensity of aerobic training should be changed every two weeks.