Understand the fat-burning mystery
BY Gary Seljaas
We know that 64 percent of the population in the U.S. is either overweight or obese.
This extra weight leads to a long list of potential risk factors for death including heart disease, Type 2 diabetes and numerous types of cancer.
The extra body fat we carry increases our risk for certain diseases, but where we carry it can make the risk go even higher. If you carry fat mostly around the waist — better known as body fat — your risk for disease increases. Women with a waist measurement of more than 35 inches and men with a waist measurement of more than 40 inches may have more health risks than people with lower waist measurements because of their body fat distribution.
Although there are various positive side effects associated with cardiovascular or aerobic fitness, one of the most important is the ability to lose body fat. Though we know it is important, it is also misunderstood. One of the most common myths is that the best way to lose fat is to build the muscle in the area you want to lose the fat, such as doing crunches to reduce abdominal fat. Although building muscle increases our ability to reduce fat, there is no evidence of spot reduction.
Though the body is complex, the process is simple. When the fat accumulates in the body it is viewed as three cells connected together known as triglycerides. Combined, these cells are too large to enter the blood stream. Once the brain realizes the body is performing aerobic exercise, however, it release an enzyme that goes to the fat cells and breaks them up into single cells. When they are separated, they have the ability to travel to the muscle and be used as a form of energy. Because the science is not exact and all humans differ, we do not know exactly how long this process takes. But the most widely recognized research indicates that it takes anywhere from 8 to 14 minutes for the brain to realize it is working in an aerobic state and requires a more efficient form of fuel, which is the fat stores in the body.
Knowing the time it takes to get to the fat burning stage, we can now see why we need to increase our aerobic exercise for extended periods of time. I have often heard people say that they go hard on the treadmill or some other form of aerobic exercise for 15 to 20 minutes at a time and they still do not seem to lower their body fat. With the research showing us that we do not even start to burn fat for up to 14 minutes, we can now see why 15 to 20 minutes is not sufficient.
The best guideline for time is to perform aerobic exercises for a minimum of 30 minutes at a time, trying to work up to 60 minutes. By doing this, we prolong the time we are in the fat burning stage, which means we are using more fat to provide energy to the muscles. There is a point of diminishing returns that differs by individual, so work to keep your aerobic workouts at about 60 minutes at a time on most days of the week.