This is an interesting argument that everyone in the fitness community is split on. I personally think that calories deficit is what matters . At a higher rate you burn more period. If fat loss is your goal it's impossible to not burn muscle as well. I trained for getting ripped the last 4 mos and noticed that I burned the most at the 75-85 percent range for 40-60 minutes on an empty stomach 3-4 times a week.
- I burned some muscle but if you keep you protein and low glycemic carbs up you can limit this catabolic state. I also expereinced alot of sucess with interval later in the cardio to bump at of your comfort zone.
-I also incorporated a 30sec rest in between sets and added more reps (12) and volume