Neglecting Aerobic Exercise

Combining cardio and strength training is the best way to burn fat. Many bodybuilders feel that aerobic exercise (prolonged exercise that works the heart and lungs steadily and increases cardiovascular fitness) is a waste of time. However lifting weights turns you into a fat burning machine. The more muscle you have, the more calories you'll burn when you do cardio.

During a specific bulk or weight gain period you may choose not to perform any type of exercise other than your heavy gym training, but aerobic exercise does have the following advantages;
1. It helps to keep your fat levels down.
2. It improves your wind during tough exercises like squats and so prevents your lungs from going out before your legs.
3. It aids recuperation and inspires regularity of appetite and bowels.
4. It hypes the metabolism.

Right after you have completed a good strength training session, it is a god idea to do 10 to 15 minutes of cardio. Because you'll have used up all your glycogen reserves (carbs stored in the muscles) for your strength training, you'll be fuelling primarily on fat during your cardio session and you'll get a really solid effort of fat burring in a short period of time.

In short, it is best to combine cardio and strength training, however if you are pressed for time, a cardio workout is the best use of your time, because you'll burn more energy overall.