It used to confuse me seeing people fail to lose weight doing exactly what I thought they were supposed to do: long, moderate cardio workouts. Supposedly you had to keep your heart rate in a “fat burning zone” — workout too hard and your body would burn carbs or protein instead of fat.

I also used to think that fat could only come off slowly.

Then last year, I read as somebody I know blogged about losing a whole bunch of weight fairly fast, while getting in shape (it was obvious he wasn’t just shedding water). That convinced me that a lot of what I’d heard before was wrong, but I still didn’t know how some people manage to lose weight and others try forever without making progress.

One key that I learned is that the weight loss formula is actually very simple:

Burn more calories than you take in, period.

In other words, you don’t have to burn calories slowly to lose weight. You just have to burn calories. And since you burn calories faster when you work out harder, you lose weight faster by working out harder.

Even though your body won’t be lighting your fat on fire to power your workout while you’re exercising, as long as you burn the calories, your body will use fat at its own pace, even after your workout, to make up the difference.

I’m not an expert at this stuff, so I don’t know exactly how long or hard you should work out or what kinds of exercises are most effective. But I came across a few fat-loss training products that don’t teach long, slow cardio: Fat Burning Furnace and Turbulence Training.

If cardio hasn’t worked for you, check ‘em out.