This also is very individual and many factors come into play when determining how many days per week you do cardio.  The key is in always changing at least one factor each week: frequency, intensity or duration.  If you only have 3 days a week to workout, increase either your intensity, duration or both.  If you have 6 days a week to do cardio, decrease your intensity days and your mix up your duration.  Keep your body guessing.

A proper cardiovascular training program includes the following protocol:
1. Changing Frequency
2. Changing Duration
3. Changing Intensity

The fantastic news is all of this has been done for you; all you have to do is show up and be faithful to your program.

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