The recommended total duration for cardiorespiratory endurance training is minutes.

The recommended total duration is 40 to 70 minutes. However, this really depends on a person's abilities and goals. Someone that is just starting running for example, should probably start with a duration of about 40 minutes of continuous exercise. However, someone who is an experienced runner training for a marathon or ultramarathon should be doing at least the occasional three to four hour session. 

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