How Much Cardio is Enough (2)?

How Much Cardio is Enough?
Cardiovascular exercise is important not only for heart health but for fat burning too - and it's a good stress reliever after a long day at work. Nothing gets your blood pumping like a good cardio session - whether it's done at home or at the gym. To get maximal benefits, how much cardio is enough?

How Much Cardio is Enough?: What the American Heart Association Says

The American Heart Association recommends doing thirty minutes of moderately intense cardiovascular exercise five days a week - or high intensity cardio for twenty minutes three times a week. This is the amount needed to condition the heart and provide the other benefits of aerobic exercise - such as lower blood pressure, blood sugar levels, higher HDL levels, and, hopefully, greater longevity. Moderately intense exercise is where you reach and maintain sixty to seventy percent of your maximum heart rate. (calculated by subtracting your age from 220). It's a pace where you'll sweat, but you'll still be able to carry on a conversation.

How Much Cardio is Enough?: It Depends on Your Goals

If your primary goal is to reduce your risk of heart disease and lower your blood pressure, thirty minutes of cardio is enough to do the job. On the other hand, if you want to burn more fat to take off a few pounds, thirty minutes of cardio may not be adequate. Why?
During the first fifteen to twenty minutes of a cardiovascular workout at moderate intensity, the primary fuel the muscles use is glycogen. It's only after fifteen to twenty minutes of aerobic exercise that significant fat breakdown starts. If you're only working out for thirty minutes, you won't tap into your fat stores for very long. If weight loss is the goal, it's better to work up to doing moderately intense cardio for fifty to sixty minutes - instead of just thirty.

What about High Intensity Cardio?

Adding some high intensity intervals to a cardio workout has additional benefits. Even though high intensity exercise burns more carbohydrates than fat for fuel, it boosts the metabolism and leads to continued fat burning even after cardio is over - the so called afterburn effect. This can work to your advantage if you're trying to lose weight.

How Much Cardio is Enough?: The Bottom Line?

To strengthen your heart, thirty minutes at a moderate intensity is fine, but if you're trying to lose weight, go a little longer or add some high intensity intervals. Always talk to your doctor before starting an exercise program - especially if you plan on doing high intensity intervals.

References:

http://www.americanheart.org/presenter.jhtml?identifier=1200013