Researchers at the University of Illinois have looked at how moderate amounts of exercise (e.g., 30-45 minutes of walking, 5 days a week), as well as the particular foods one eats, influence the amount of inflammation present in visceral fat (aka “belly fat”).
Because abdominal fat is now seen as a growing health hazard, an indicator and contributor to “Syndrome X”, or metabolic syndrome.
The risks of metabolic syndrome go far beyond a bulge at your waistline. “Belly fat” is particularly dangerous because it produces inflammatory molecules that enter the bloodstream and increase the risk of heart disease, high blood pressure, high cholesterol, and diabetes.
If you’re over 40, it’s time to get serious about reducing your abdominal fat. Not just for your waistline, but to dramatically reduce your risk of chronic disease.
The study revealed that moderate exercise can make the body more sensitive to insulin (insulin sensitivity), even without a change in diet. (If the body’s cells are not sensitive to insulin, then sugar levels are not regulated as they should be.) Exercise was also found to decrease fat in the liver and decrease inflammation in the belly fat.
“Scientists now know that obesity is associated with a low-grade systemic inflammation. Obese people have higher levels of circulating inflammatory markers, such as C-reactive protein (CRP), which are produced and secreted by fat tissue. This inflammation then triggers the systemic diseases linked with metabolic syndrome, such as Type 2 diabetes and heart disease,” said Jeffrey Woods, a U of I professor of kinesiology and community health and faculty member in the U of I Division of Nutritional Sciences and the Integrative Immunology and Behavior Program.
The Illinois researchers, whose work was published recently in The American Journal of Physiology, Endocrinology and Metabolism, looked at the effects of both diet and exercise on inflammation of visceral fat in mice. Their study included a high-fat diet group to induce obesity. Six weeks into the study, mice were divided either into a sedentary group, an exercise group, a low-fat diet group, or a group that participated in both exercise and the low-fat diet. The study was divided into 6- and 12-week increments so the scientists could examine both the short- and long-term effects of the interventions.
Interestingly, the results achieved by the combination exercise/diet group were not significantly better than those of the diet or exercise groups by themselves.
Perhaps even more surprising is the fact that the only truly significant increase in belly fat in the mice from 6 to 12 weeks was seen in the sedentary mice. This may suggest that exercise is an important lifestyle intervention that can help fight inflammation in the belly fat, even in the presence of a high-fat diet. The researchers stated that exercise could help prevent life-threatening diseases even in people with obesity, by decreasing inflammation.
A second study of sedentary older adults published in a recent issue of Brain, Behavior and Immunity (BBI) reinforced these findings.
In that 10-month study, one group of sedentary older adults participated in three 45- to 60-minute cardiovascular exercise sessions per week, while another group focused on exercises to improve non-cardiovascular flexibility and balance for 75 minutes twice a week.
“At the end of the study, the ‘cardio’ group had lower levels of C-reactive protein (CRP), less belly fat, and improved general fitness than the ‘flex’ group,” said Ph.D. candidate Vieira.
“The lower CRP levels were partially mediated by the reduction in trunk fat,” she explained.
The take-home message here: Even if you’re having a hard time lowering the fat and calories in your diet, you can still improve your health and possibly lower belly fat with even moderate amounts of exercise. Regular physical activity could also help you with stress reduction, which may further help lower your risk of disease and could also help you to cut back on the nervous eating we often do in response to stress.
So what do we mean by ‘moderate’ exercise? Where does the rubber meet the road?
Well, it’s a relative thing…
If you’ve been living a very sedentary life, then you can start by walking. Spend 20-30 minutes 2-3 times per week, and walk at a pace that gets your Target Heart Rate to within a particular range of your maximum heart rate.
Need help figuring out what that means? Simple math…
You can easily find your Target Heart Rate with this simple method:
Subtract your age from 220 (226 for women) to calculate your Maximum Heart Rate (mhr).
Find your training zone below and multiply that number times your maximum rate.
EXAMPLE: 40 year old male; 220-40=180 (Maximum Heart Rate, or MHR). For a warm-up, healthy heart range, we’d multiply 180 x .50=90 and 180 x .60= 108. Thus, the guy’s warm-up range equals between 90 and 108 beats per minute. For a 40 year old Female: 226-40= 186 (MHR); For that same warm-up, healthy heart range- 186 x .50= 93; x .60= 111.6. Thus, her warm-up, healthy heart range is between 93 and 111.6 beats per minute. And I think we can round it down to 111!
If you want to work in one of the other zones, find the appropriate categories and adjust the range to the higher category.
To determine which of these following ranges to work within depends on your particular goals, and I urge you to check with your primary care practitioner before embarking on ANY new fitness regimen! But for some basic guidelines, here are some standard training zones that are used within the fitness industry:
Healthy Heart Zone (Warm up) — 50 – 60% of maximum heart rate: The easiest zone and probably the best zone for people just starting a fitness program. It can also be used as a warm up for more serious walkers. This zone has been shown to help decrease body fat, blood pressure and cholesterol. It also decreases the risk of degenerative diseases and has a low risk of injury. 85% of calories burned in this zone are fats!
Fitness Zone (Fat Burning) — 60 – 70% of maximum heart rate: This zone provides the same benefits as the healthy heart zone, but is more intense and burns more total calories. The percent of fat calories is still 85%.
If you’ve already been exercising, and are ready for something aimed at increasing your endurance, then you can aim for this:
Aerobic Zone (Endurance Training) — 70 – 80% of maximum heart rate: The aerobic zone will improve your cardiovascular and respiratory system AND increase the size and strength of your heart. This is the preferred zone if you are training for an endurance event. More calories are burned with 50% from fat.
I hope this helps you understand how to begin to win the belly fat battle…
I assure you that you CAN do this, and you’ll feel better for beginning!