Welcome to InCirculation.net
InCirculation.net is a professional cardiovascular resource intended for a global audience of specialists, generalists, researchers, and other healthcare professionals
Cardiovascular news provides daily news updates to help you stay informed.
Cocoa flavanol consumption does not enhance effects of exercise on obesity
18 August 2008
MedWire News: Consumption of high levels of cocoa flavanols improves endothelial function, but does not enhance the effect of exercise on body fat or fat metabolism in obese individuals, show study results.
"Impaired endothelial function in obesity may reduce blood flow to sites of metabolism, contributing to impaired fat oxidation and insulin resistance," comment Peter Howe and colleagues from the University of South Australia in Adelaide, Australia.
A high intake of cocoa flavanols is known to improve endothelial function by increasing flow mediated dilation of the brachial artery (FMD), as reported by MedWire News, and has also been linked to reductions in body fat in some previous studies.
Howe and team attempted to determine whether cocoa flavanol consumption would improve cardiometabolic function and body composition of a group of 49 obese men and women with an average body mass index (BMI) of 33.5 kg/m2 aged 45 years on average. They also tested whether taking part in an exercise program would enhance the effects of cocoa flavanols.
The study took place over 12 weeks and participants were randomized to one of four groups, namely, high-flavanol cocoa (902 mg/d flavanols), high-flavanol cocoa plus exercise (3 x 45 min/week), low-flavanol cocoa (36 mg/d), and low-flavanol cocoa plus exercise.
Endothelial function was assessed using FMD and fat oxidation by indirect calorimetry at baseline, 6, and 12 weeks. Body composition was measured by dual-energy X-ray absorptiometry at 0 and 12 weeks.
As reported in the International Journal of Obesity, participants who consumed high levels of flavanols during the study had 1.6% higher FMD at 12 weeks compared with those consuming low levels of flavanols.
In addition, those who took part in the exercise program had increased fat oxidation (by 0.10 g/min) and decreased abdominal fat (by 0.92%) compared with those who did not.
However, the researchers observed no significant interactions between flavanol consumption and exercise.
Howe et al conclude that despite the fact that high flavanol consumption did not enhance the effects of exercise on body fat or fat metabolism in the obese, "it may be useful for reducing cardiometabolic risk factors in this population."
