Over the years I have heard and read many "theories" about fitness and exercise that have led me to be skeptical. One such notion is that doing cardiovascular exercise will prevent muscle growth and will actually lead to muscle loss. It has become apparent to me that many believe in this idea since when at the gym, typically the muscle-bound creatures are rarely seen approaching a piece of cardio equipment. Most stay comfortably confined within the free weight area and focus solely on resistance training and see cardio exercise of a waste of time that takes away from what truly will build muscle.

Let me explain why, for the average person, this is not true. First off, yes, when you are engaged in physical activity you are constantly breaking down and re-building muscle tissue, regardless if it is cardio or weight training. This process is called "protein turnover." Your body is constantly alternating back and forth between anabolic (building) and catabolic (breaking down) cycles. This is basic human physiology has often been taken out of context and used to scare people into not doing cardiovascular exercise for fear of losing muscle. When you fast overnight as you sleep, you lose muscle too, but that doesn't mean you should stop sleeping, right?! We cannot change the fact that, at times, our bodies use protein for fuel instead of fat and carbohydrates. Your goal is simply to tip the scales slightly in favor of increasing the anabolic side and reducing the catabolic side just enough so you gain or at least maintain muscle.

Sure, if you do highly excessive amount of cardio you can sacrifice muscle, but unless you are riding like Lance Armstrong or doing 20-mile marathon training runs, it is highly unlikely that you will turn into a pip-squeak by doing aerobic activity along with strength training. In fact, cardio can enhance muscle growth by promoting blood flow and oxygen to your muscles. The increase in blood flow supplies nutrients to the muscles while also carrying waste products away to speed up growth and recovery. If you are eating good amounts of protein combined with complex carbohydrates, and eating enough calories to keep you from going into "starvation mode", you should have no problem gaining/keeping muscle mass with your strength and cardio program.

Now that I have hopefully convinced you that cardiovascular exercise will not hinder muscle growth or maintenance, the best reason to engage in it is for your heart health and muscle endurance. Your heart is a huge muscle and it needs to be regularly overloaded just like your biceps and quads to be stronger and healthier. It would be very interesting to see how people would prioritize their workouts if their bodies were turned inside out! Probably a lot more cardio since it keeps blood pressure, cholesterol, blood sugar and body fat under control. If you neglect your heart muscle but work all of the others. . . well, you may be looking mighty buff at your funeral. Bad humor, I know. . . but something to think about.