Q: In light of question 42, is it true that staying at lower intensity will burn more fat calories? Is this the approach someone should take (lower intensity, longer duration) if he/she wants to lose weight?

A: No, that is not correct. I apologize that my answer to #42 was not clear. If you are talking about cardio, then the number of calories burned is roughly proportional to the distance covered or to the work performed and NOT to the time spent. In other words, if you jog 2 miles in 20 minutes, you'll burn just as many calories as covering the same 2 miles in 40 miutes. (In fact, your cardiovascular system will benefit more from the faster pace, but either pace is much better than not doing the exercise at all :) I do not usually recommend all-out exhausting cardio because I view cardio only as a supplement to weight training for general population and exhaustive cardio will interfere with muscle recovery from weight training. So moderate-to-brisk pace is probably optimal cardio. Exceptions to this rule are athletes who train for endurance sports and who need high-intensity cardio as part of their training.

If you are talking about weight training, then the answer is still no -- the reason weight training can be such an effective fat-burner is because muscle recovery has very high metabolic requirements. In other words, you burn most calories while resting in between lifting sessions. So you want to punish your muscles in the gym to force them into heavy recovery. And the best way to do so is with high weights and low reps (12 reps or less before muscular exhaustion or failure).

So in either case, lowering intensity does not buy you anything as far as additional fat burning. That's not to say that low intensity is always bad. Low intensity exercising is very appropriate for beginners, older people, those recovering from injuries or from overtraining, and those who are simply due for a break from intense exercising (my rule of thumb is at least one week of rest or very light exercising for every two months of normal training).