Frequency - In general, cardio should be performed 3-5 times per week without more than 48 hours of rest passing between sessions. Any longer than 48 hours and your body starts to lose the positive effects of the previous session(s).
Duration - 20-60 minutes per session is sufficient for intermediate and advanced cardio fitness levels. For beginners, 1-2 small sessions of 10-12 minutes (not including warm-up/cool-down periods) should be performed for the first few weeks, then gradually up the duration per session each week thereafter as your body progresses.
Intensity - Using an appropriate intensity level is key to obtaining significant results from any type of cardio activity. Beginners should work at a pace below 55% of their maximum heart rate for a few weeks to build a strong tolerance to the cardio activity before raising the intensity level. While intermediate and advanced individuals should work at a pace of 55/65-90% of their maximum heart rate
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