Phop, there is no definitive answer to that. You reduce body fat by creating a caloric deficit, however you go about that (be it exercise or diet induced, or both).

I'm sure You've heard the Moderate Cardio Burns More Fat Myth. If not here it is in a nutshell: Low or moderate intesity exercise burns approximately 50% of its calories from Fat. High intensity cardio burns about 40% of its calories from Fat. It would appear that you'd burn more calories from low / moderate cardio. However, you burn more total calories doing high intensity cardio.

For example, if you burn 100 calories in 20 minutes of low / moderate cardio compared to 160 calories in 10 minutes of high intensity cardio, you've still burned more total fat doing high intensity cardio.

High intensity training has another added bonus. It raises your metabolism long after you've finished working out. Low / moderate intensity training does not do this.

The general recommendation for fat loss is to workout three to five times per week at 20 to 40 minutes per session. Start conservatively if you are just starting training, e.g. three times per week, 20 minutes per session.

Like you, I was very, very hesitant to give up my cardio for the BFL 20 MAS three times a week. But I did - and it worked. I think part of why it worked so well was that it was such a big change. Our bodies respond to change - I'd been doing moderate intensity cardio for years. This was very different and it worked very well.

If you decide to do more you should read the sticky at the top of this forum 'BFL w/ LC: Tips and Hints" - especially the section on doing extra cardio. You run the risk of jeopardizing muscle growth if you increase cardio and do not also increase protein and if you short-change yourself on your sleep.

HTH
Nat