If you want to lose weight by doing cardio training, you won’t achieve much if you train at such a low level that you can keep on chatting while exercising. According to a study done by geriatrists at the University of Arkansas, daily cardio training at 50 percent of their VO2max is unlikely to be of much benefit to elderly people. They only start to lose abdominal fat by training at 75 percent of their VO2max.
Abdominal or visceral fat is dangerous fat. The fat that your body stores around the organs increases your bad cholesterol levels, aggravates inflammation and makes you less sensitive to insulin. Fortunately abdominal fat is also the first fat you lose when you start to lose weight.
For the elderly in particular, increasing energy burning is a better way to lose weight than eating less. A safe way to burn more is cycling. But if elderly people cycle in a gym, what’s the best intensity? That’s the questions these researchers wanted to answer. So they recruited 18 healthy men and women aged between 65 and 90. Twelve of them had to cycle 4-5 days a week in a gym, for a period of 12 weeks. The test subjects burned a total of 1000 kcal each week: no more and no less.
All of the subjects were overweight, with an average BMI of 30.
After twelve weeks the researchers saw that both groups that had trained had become fitter. Their VO2max and their maximal capacity had increased. There was hardly any difference between the two groups. Nothing had changed in the control group.
When the researchers measured the subjects’ body composition, they observed that in both of the groups that had trained the amount of subcutaneous fat had decreased by the same amount, which was not statistically significant. In the control group there had been an equally statistically insignificant increase.
There were significant differences in the amount of abdominal fat lost by the test subjects, however. The HI group lost considerably more abdominal fat than the MI group.
Why more intensive cardio training works better the researchers do not say. We, based on our limited knowledge, suspect that the body produces more pep hormones like adrenalin at a higher intensity, and that the body more easily lays claim to its fat reserves. A second factor may be the EPOC, the higher level of energy burning experienced after a training session. The more intensive the training, the more intensive the EPOC.
If this theory is correct, then moderate intensity cardio training after a strength training session might be effective. Strength training increases the production of adrenalins, and the EPOC is higher after strength training. Combining strength training and moderate cardio training could give you the best of both worlds.
Influence of exercise intensity on abdominal fat and adiponectin in elderly adults.
To examine the influence of moderate-intensity (50% of VO(2peak)) exercise training (MI) versus high-intensity (75% of VO(2peak)) exercise training (HI) on regional fat distribution and plasma adiponectin, we randomized 18 overweight (body mass index [BMI] = 30 +/- 1 kg/m(2)) elderly (71 +/- 1 years) to HI, MI, or a control group (CON). Subjects enrolled in HI or MI completed a 12-week exercise training protocol designed to expend 1000 kcal/week. Body composition testing was completed prior to and following the exercise training using dual energy X-ray absorptiometry and a computed tomography scan. Plasma adiponectin was measured using enzymelinked immunoassay (ELISA). VO(2peak) improved in HI and MI, whereas there was no change in VO(2peak) in CON. No significant change in body weight, BMI, and % fat occurred in MI, HI, or CON. Although there was a significant reduction in visceral fat with HI (-39 cm(2)), there was no change in the MI or CON groups. In addition, there was a significant increase in thigh muscle attenuation in the HI group. There were no changes in thigh muscle attenuation in the MI and CON groups. Also, there was no change in plasma adiponectin in the MI, HI, or CON groups. In summary, our direct comparison of exercise intensity without weight loss promotes the efficacy of HI in the reduction in visceral fat, even without changes in adiponectin.
PMID: 19196080 [PubMed – indexed for MEDLINE] PMCID: PMC3135883