To complement the intense weight training that bodybuilders and figure athletes use to build muscle, cardiovascular training is worked into the routine to burn excess fat. What many people have a hard time balancing is the tradeoff between muscle mass maintenance and fat burning. It's a very fine line that must be navigated carefully.
Cardiovascular exercise in the form of peddling a bike, running a treadmill, using a step machine or lap swimming serves several purposes. The first is to increase your body's cardiovascular capacity and build up endurance. Regular cardio increases your physical capacity for exercise.
Marathon runners, triathletes and other endurance athletes train long and hard to be competitive in their sport. Their primary goal is to become conditioned to the point where they can outpace and outlast their competition. They push themselves to run, bike and swim faster, longer and harder during every workout. In the process, they also burn a tremendous amount of calories.
Physique athletes engage in cardio exercise for a different reason. They're focused on reducing body fat to achieve a ripped, hard look. So the intensity of their cardio is going to be dialed way down from what endurance athletes typically engage in. The goal isn't to burn calories. It's to burn fat.
During anaerobic weight training, your body uses sugar (carbohydrates) for fuel. This high-intensity form of exercise requires a fast-acting source of energy. In the process, you're tearing down muscle so it will grow back bigger and stronger. If you apply this same level of intensity to your cardio training you'll also burn sugar for energy instead of the targeted body fat. Worse, you risk sacrificing muscle due to breakdown from the intensity of exercise.
The best type of cardio for burning stored fat is moderately intense, but nowhere near high intensity. The goal is to get your heart rate up so your body uses fat to fuel exercise. Bodybuilders and figure athletes who are reducing their carbohydrate intake often find themselves sacrificing muscle mass when they do either too much cardio or put too much intensity into the cardio effort. Don't make this mistake if your goal is a lean muscular physique.
Natural Mr. Olympia
John Hansen
