Yes, we know it. If you look at wall charts or cardio equipment in a gym, or listen to many personal trainers, you are indoctrinated about the "fat burning zone". The default tips for entering this zone are to exercise at about 60 percent of your maximum heart rate. That level of exertion is relatively low intensity; Most people can speak in complete sentences while exercising on it. Working in this zone, it is said, will burn more fat and result in greater long-term weight loss, compared to doing the same exercise at higher intensities.
There is substance to part of this requirement. Your body burns itself by burning a mixture of stored fat and carbohydrates. The less active you are at a given time, the greater the percentage of that fuel mixture coming from fat. As the intensity of activity increases, the percentage of carbohydrates in that fuel mixture also increases. At rest, fat accounts for as much as 85 percent of calories burned. That figure moves to around 70 percent in an easy walking distance. If you switch to a moderate effort, the mix will be about 50 percent fat and 50 percent carbohydrates, and the faster you go toward carbohydrates.
So it is true that in some exercise intensities you burn a higher percentage of fat than at other intensities. But that doesn't mean that this biological process is the key to losing weight from exercise. Experts explain that those who believe in a melting zone simply do not see the forest, that is, what is really needed to lose weight ̵
First, although it may sound better for weight loss to burn a higher percentage of fat, the reality of the intensity of your body composition is almost zero. "The idea that suddenly when you hit this zone, the fat is just sucked out of your system, simplified," said Christopher Breen, a training physiologist and online trainer in Long Island. "It totally ignores that losing or maintaining weight is basically a matter of calories in relation to calories out."
If the key factor for weight loss was the percentage of fat you burn, it would be best for you to remain silent because that is when you burn the highest percentage of fat compared to carbohydrates. But as Breen says, total calories are burned, what matters, and that fact leads to the second major problem of fat burning.
"If you exercise with this lower intensity, you burn fewer calories per minute," says Christine Brooks, University of Florida Assistant Instructor and Coaching Science Coordinator for the USA Track & Field. "The average person going for an hour should only burn a few hundred calories. "At that time, you can burn more than twice as many calories that run, cycle or use a moderate intensity elliptical machine.
Let's be real: When planning a workout, you probably think when It is about time, not the number of calories burned, so in the probable scenario that you have 30 or 45 minutes of training before or after work, you just won't burn as many calories if you spend that time in the fat burning zone. "I'm All for people to become more active, but most will not regularly post the time at lower intensity to create a calorie deficit, Brooks says.
Also, if you want to get all geeky, the math argues against the fat burning area. Walk two miles in an hour, and you will burn about 200 calories, with about 140 of those raised by fat. Cycle moderately for that time, and you'll burn about 500 calories, with about 250 of those raised by fat – so you'll burn more calories and more fat. "When I worked with people in a gym, I would tell them:" In the past, it's a matter of calories, the fat burning will take care of itself, "Breen says.
Another trick for more powerful workouts "You get a post-burn effect." You maintain a higher metabolic rate after higher intensity exercise, "says Brooks." The reason is that more damage is done to different systems, giving you increased heart rate while the body is making necessary repairs. "
" I have a real steak with the way this fat-burning idea is promoted, says Brooks. "It's a very strange way of talking about exercise." She and Breen agree that the myth persists because it is a simple concept to understand. "It's a way to make exercise machines more appealing – if I work at this speed, I will burn more fat than any other speed," says Breen.
None of this is suggesting low intensity exercise is a waste of time. Even the best athletes in the world regularly and purposefully train with an effort. A gentle jog or simple spin is a great way to clear your head, get reenergized, improve your health, spend time with friends and family, and yes, burn some calories.
"Mix it up," says Breen about structuring your workouts. "Have some harder, high intensity days, followed by simpler, low intensity recovery days." Aim also at different durations. When you have time, make longer workouts at a comfortable level of effort. When you are pressed for the moment, you work a little harder. The table in our heart rate training guide helps you build a well-rounded exercise program.
Variety in workouts will keep you healthier physically and mentally than if you do the same day after day. That freshness will make you more likely to exercise consistently. And it is the zone that will result in long-term weight loss.
This article was written by Scott Douglas a reporter for The Washington Post.
Douglas is a contributing author of Runner's World and the author of several books, including "Running Is My Therapy."