Q: A lot of gym equipment has a "fat burning zone" meter but I don't know what that means. Am I supposed to stay in that zone?
A: You can’t get onto a piece of cardio equipment these days without seeing the chart showing you where you need to get your heart rate in order to be in the sexily named: “Fat Burning Zone.”
The Fat Burning Zone is a state of exercise that lies above resting, but not quiet at the point of being “aerobic.” It’s typically a slower, steady exercise that shouldn’t take too much exertion to stay in. Walking, slow biking, and a leisurely swim would all fall under Fat Burning Zone. Don’t feel that fat melting off quite yet?
The Fat Burning Zone has a great name. I mean EVERYBODY wants to burn fat. However, while accurate in its portrayal that you are burning a higher percentage of fat in this zone (about 66% of what you burn will be from fat, and only 34% from carbohydrates), your overall caloric burn won’t be very high (whomp whomp). The fat will burn, but at a very slow rate.
Those who up their intensity past the fat burning zone will burn a lower percentage of fat (only 44% of what they burn will be from fat, and 56% from carbohydrates) however, the overall caloric burn will be more, meaning burning more overall carbs AND fat.
Still confused? Here’s an example:
Sally decides to walk for 30 minutes in the fat burning zone. “I shall burn all fat!” Sally exclaims. “I will burn more fat than my friend Jessica, because Jessica is in the aerobic zone. Aerobic zones are just for conditioning, but I want to lose fat, and therefore am in the FAT BURNING ZONE.” Misguided, Sally takes off on her walk.
Jessica, meanwhile, ups her intensity to a jog where she’s breathing heavier than Sally, and working harder. Her heart rate is elevated and her blood is pumping. She is in the aerobic zone for the next 30 minutes.
So let’s compare notes from Sally and Jessica’s workouts.
Sally: Average heart rate: 115 beats per minute. Overall calories burned: 130. Calories from carbohydrates burned (34%): 44. Calories from fat burned in the fat burning zone (66% of her overall 130 calories): 85. Good job Sally!
Jessica: Average heart rate: 145 beats per minute. Overall calories burned: 325. Calories from carbohydrates burned (56%): 182. Calories from fat burned (44% of her overall 325 calories): 143. Killer workout Jessica!
So you see, while doing less intensity to burn more fat sounds like a dream, it’s not quite the fat burn you’re looking for. Sally did burn a higher percentage of calories from fat, but because the overall caloric burn was so low, she ended up burning a lot less fat than Jessica. Meanwhile Jessica not only burned more calories from fat, but burned twice as many calories in general from just upping her intensity.
Now, don’t get me wrong, the fat burning zone is great for rest days or days where you’re looking for a lighter workout. And trust me, those days are important and should be incorporated into every workout schedule. But for your fat zapping workout – I say get out of the fat burning zone and bring the intensity!