Should I work out on an empty stomach? For years, this has been one of the most common questions I've been asked by people looking to lose weight. According to some research, it makes total sense to train in a fasted state on some workout days, and I can tell you from first-hand experience that fasted high-intensity cardio-like interval speed bursts produces superior fat-loss results.

It may go against the golden rule of meal timing - that your biggest meal should come right after your workout - but for one day a week, change things up and keep your body in a fasted state a little longer (1 to 2 hours) after you finish a short bout of sprints. And for athletes on a low-carb diet, the effects will be even more pronounced.

Just make sure that your intensity is high and your duration is short.

In fact, intensity and duration are inversely related. After all, you can only sprint for so long, right? So it follows that if you're training for an hour, your intensity must be reduced to allow you to last that long. That's not what we want here. Remember, on a low-carb diet, you should be doing about 5 to 10 minutes of high-intensity work with the option of following those interval speed bursts with some light cardio for another 30 minutes or so.

Intensity is the key to losing fat and staying lean because it triggers the release of hormones that preserve muscle (i.e., growth hormone and testosterone) and help unlock stored fat. If possible, do your best to perform your interval speed bursts (and most of your workouts) first thing upon waking in the morning after an overnight fast. If your schedule only allows you to work out later in the evening, make sure to wait 3 to 4 hours after a meal before training for maximum fat burning. This will ensure that insulin is low and your body more readily taps into its fat stores as a source of fuel for your workout.

Research has suggested that carb intake before or during an exercise session can blunt the expression of several metabolic genes following exercise. Insulin may play a role here. Another way to think of it is that providing nutrients to the body makes it experience exercise as less of a stressor than fasted-state training. Why should it adapt or compensate when all the fuel it needs has been provided?

So should you exercise in a fasted state all the time? No. But you certainly can on certain days, like when carb intake (and thus insulin) will be low. Fasted exercise means that you're working out when your blood sugar and glycogen stores might be a little low. This often makes fasted workouts more challenging - you simply don't have enough fuel in the tank. But again, you should only be exercising at a high intensity for only 5 to 10 minutes here, which will exert the perfect amount of energy.

The cool part about fasted exercise and higher-intensity exercise is that both train your body to become a better fat-burning machine. And they've even been shown to have favourable effects on muscle building compared with training in a fed state, especially where strength training has been employed.

Can't make it through a fasted workout? Don't stress, but don't go fuelling up on a full dish either. Eat a small amount of protein (some protein powder in water), and you'll benefit your metabolism, and help burn fat, all at the same time.