On the surface, it seems to make sense. Exercise first thing in the morning on an empty stomach and your body should burn more fat. After all, without food intake for eight to 12 hours, you are in a fasted state. With glycogen stores depleted and low morning insulin levels, your body has to turn to other energy sources to power through your workout, and it’s more likely to turn to fat for fuel.
Fasted cardio is a technique that has been around for years in the bodybuilding community, and one that’s gaining popularity among regular gym goers and even endurance athletes. But will forgoing your morning oatmeal really lead to a leaner body and better athletic performance?
Here’s the skinny on sweating it out sans food and whether or not it is suitable for your body and fitness goals.
The Fast Track to Fat Loss?
Early morning, un-fueled workouts are a common protocol among bodybuilders, especially in preparation for competition when they need to lean out as much as possible before they walk on stage. Some celebrities also turn to this technique to get ready for their close-up, whether that’s a photo shoot or red carpet event.
“Is fasted cardio a good way to burn fat? The answer is yes and the answer is also no,” says Jay Cardiello, a NSCA and ISSA-certified strength and conditioning and fitness expert who has worked with celebrities such as Jennifer Lopez, Curtis “50 Cent” Jackson and Sofia Vergara. “It’s effective, but it’s not sustainable,” he says.
Some studies have found that exercising in a fasted state can burn almost 20 percent more fat to exercising with fuel in the tank. Why? Once we eat, insulin (which regulates the breakdown of fat) increases in our body. And, according to some research, higher insulin levels have been shown to suppress fat metabolism by up to 22 percent.
However, research has demonstrated that fasted cardio does not increase fat burning over a 24-hour period. While your muscles adapt to using more fat when you exercise, you don’t actually lose more fat overall on the days that you exercise compared to days that you don’t. Another study suggests that ingesting carbs before working out increases the post-exercise “afterburn” effect more than the fasted state. That means more calories burned throughout the day, not just during your sweat session. —Christine Yu for Life by DailyBurn
Want more? Head over to Life by DailyBurn to learn whether or not fasted cardio really burns more fat.