hahha gym rats are notorious for passing along "I heard" info. In this case your friend is correct. prolonged bouts of cardio can be catabolic to muscles.

High Intensity Interval Training (HIIT) has been shown to be much more effective at burning fat, then prolonged cardio. In addition to that, it is much easier to fit into your schedual. Do a search for HIIT and you will find all the info you need.

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