If you're struggling to lose belly fat — which is the most damaging type of fat to your health — then you'll have more success with aerobic exercise than with resistance training, according to a new study from researchers at Duke University.
The study, published in the most recent edition of the American Journal of Physiology, found that aerobic exercise consumed 67 per cent more calories than resistance training. Aerobic exercise was defined as “any physical activity that raises the heartbeat and makes the lungs and heart work harder to meet the body's increased demand for oxygen” and also raises the circulation of oxygen throughout the bloodstream (examples included running, jogging, swimming and cycling), while resistance training was defined as “any physical activity that uses the force of a muscle against some kind of resistance to build muscle strength and size” (e.g. weight training, push-ups and chin-ups).
Lead author Cris Slentz, PhD, wrote: “When it comes to increased health risks, where fat is deposited in the body is more important than how much fat you have. Our study sought to identify the most effective form of exercise to get rid of that unhealthy fat.”
“Resistance training is great for improving strength and increasing lean body mass. But if you are overweight, which two-thirds of the population is, and you want to lose belly fat, aerobic exercise is the better choice because it burns more calories,” Slentz added.
Belly fat is fat that is located inside the abdominal cavity, packed in between vital organs like the stomach, liver and intestines. It is different from fat under the skin (subcutaneous fat) and intramuscular fat, which is interspersed in the skeletal muscles. People with excessive amounts of belly fat have a higher risk of developing heart problems, diabetes and some forms of cancer.
In the study, 196 patients between the ages of 18 and 70 who were overweight and led sedentary lifestyles were randomly split into three groups and monitored closely. One group did strictly aerobic training (the equivalent of 12 miles of jogging per week, reaching 80 per cent of their maximum heart rate), one group did strictly resistance training (three sets of 8-12 repetitions three times per week), and one group combined the two.
Researchers found that those who did aerobic training not only lost more belly fat, but also saw better improvements in fasting insulin resistance, reduced liver enzymes and fasting triglyceride levels.
While the training program used in this study was “rigorous and substantial,” researchers believe people can achieve results with less strenuous regimes.
“What really counts is how much exercise you do, how many miles you walk, and how many calories you burn. If you choose to work at a lower aerobic intensity, it will simply take longer to burn the same amount of unhealthy fat,” Slentz said.
According to a new study from Marshall University and published in the journal Nutrition and Cancer, the risk of developing breast cancer may be reduced by introducing one simple ingredient into your diet: walnuts.
The study looked at the effects of a “modest amount” of walnuts in the diet of mice throughout their lifespan, obtaining it both from the mother in weaning and eating it directly. The amount given to the mice would equate to roughly two ounces per day for humans.
Researchers found that, during the study period, the group whose diet included walnuts developed breast cancer at less than half the rate of those who consumed a typical diet. And even those who did develop breast cancer had smaller and fewer tumours.
“These reductions are particularly important when you consider that the mice were genetically programmed to develop cancer at a high rate,” said Elaine Hardman, PhD, of Marshall's Joan C. Edwards School of Medicine, who led the study. “We were able to reduce the risk for cancer even in the presence of a pre-existing genetic mutation.”
The study found that the diet containing walnuts changed the activity of certain genes that are relevant to breast cancer in both mice and humans. More testing showed that increases in omega-3 fatty acids did not fully account for the cancer-preventing effect, but tumour growth decreased when the amount of vitamin E in the diet goes up.
“Food is important medicine in our diet,” Hardman said. “What we put into our bodies makes a big difference — it determines how the body functions, our reaction to illness and health. The simple stuff really works: eat right, get off the couch, and turn off the TV.
“The results of this study indicate that increased consumption of walnut could be part of a healthy diet and reduce risk for cancer in future generations.”
