You are correct, the point of HIIT is to increase your resting metabolism after the workout. The bursts of higher intensity will increase blood flow to fat and muscle, causing you to release fatty acids. And the effect of this method is increasing your resting metabolism.
It also helps minimize muscle loss.
You should feel tired after the HIIT. Dont gauge the effectiveness on how you feel though. If you are doing it properly, its working. Dont negate the effects of the HIIT by adding extra cardio and going for longer. This will most likely turn into a catabolic event, and thats definitely not what you want.
Remember, its the after workout effects that you are looking for.
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TEAM NORTON
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