- In older adults with obesity, the combination of aerobic exercise with a moderate reduction in total daily calories resulted in greater improvements in vascular health compared to exercise alone.
- Reducing caloric intake by about 250 calories per day can result in significant weight loss and improve vascular health in older adults with obesity.
Reducing just 250 calories a day with moderate exercise had greater benefits for older, obese adults than exercise alone. In older adults with obesity, combining aerobic exercise with a moderate reduction in daily caloric intake resulted in greater improvements in aortic stiffness (a measure of vascular health that affects cardiovascular disease) compared to exercise alone or Exercise Plus a more restrictive diet on new research published today in the American Heart Association’s flagship journal Circulation.
Modifiable lifestyle factors such as a healthy diet and regular physical activity can help offset the age-related increase in aortic stiffness. Although aerobic exercise generally has beneficial effects on aortic structure and function, previous studies have shown that exercise alone may not be enough to improve aortic rigidity in older adults with obesity.
“This is the first study to examine the effects of aerobic exercise, with and without calorie restriction, on aortic stiffness, measured using cardiovascular magnetic resonance imaging (CMR) to obtain detailed images of the aorta,” said Tina E. Brinkley, Ph. .D., First author of the study and associate professor of gerontology and geriatric medicine at the Sticht Center for Healthy Aging and
“> Alzheimer’s Prevention at the Wake Forest School of Medicine in Winston-Salem, North Carolina. “We wanted to find out if additional calorie restriction for weight loss in older adults with obesity would result in greater improvements in vascular health compared to aerobic exercise alone.”
This randomized controlled study included 160 sedentary adults aged 65–79 years with obesity (BMI = 30–45 kg / m2). The average age of the participants was 69 years; 74% were female; and 73% were white. Participants were randomly assigned to one of three intervention groups for 20 weeks: 1) exercise with only their regular diet; 2) exercise plus moderate calorie restriction (reduction of approximately 250 calories / day); or 3) Sport plus more intensive calorie restriction (reduction of approx. 600 calories / day).
The two reduced calorie groups received pre-made lunches and dinners with less than 30% calories from fat and at least 0.8 grams of protein per kg of their ideal body weight, prepared under the guidance of a registered dietitian for the study; They made their own breakfast according to the dietician-approved menu. All study participants received supervised aerobic exercise four days a week during the 20-week study at the Geriatric Research Center of the Wake Forest School of Medicine.
The structure and function of the aorta were assessed using cardiovascular magnetic resonance imaging to measure the aortic arch pulse wave velocity (PWV) (the speed at which blood flows through the aorta) and the expandability, or ability of the aorta to expand and contract. Higher PWV values and lower extensibility values indicate a stiffer aorta.
The results showed that a weight loss of nearly 10% of total body weight, or about 20 pounds, over the five-month study period was associated with significant improvements in aortic stiffness – only among participants assigned to the athletic plus moderate calorie restriction group. Additional findings are:
- The physical activity plus moderate calorie restriction group had a 21% increase in extensibility and an 8% decrease in PWV.
- None of the measurements of aortic stiffness changed significantly, neither in the group with pure training nor in the group with more intense calorie restriction.
- The changes in BMI, total fat mass, percentage body fat, belly fat and waist circumference were greater in both calorie-reduced groups than in the training group alone.
- Weight loss was similar between the calorie restricted groups, despite almost twice fewer calories (26.7% calorie reduction vs. 14.2% calorie reduction) in the high calorie restriction group.
“Our results show that lifestyle changes aimed at increasing aerobic activity and moderately reducing daily caloric intake can help reduce aortic stiffness and improve overall vascular health,” said Brinkley. “We were surprised, however, that the group that reduced their caloric intake the most showed no improvement in aortic stiffness, even though they had similar decreases in body weight and blood pressure as the participants with moderate caloric restriction.”
Brinkley added, “These results suggest that combining exercise with moderate calorie restriction – as opposed to more intense calorie restriction or calorie-free restriction – is likely to maximize vascular health benefits while reducing weight and improving body composition and fat distribution optimized. The realization that higher-intensity calorie restriction may not be necessary or advisable has important implications for weight loss recommendations to improve the risk of cardiovascular disease in older adults with obesity. “
Reference: “Effects of Exercise and Weight Loss on Proximal Aortic Stiffness in Older Adults with Obesity” by Tina E. Brinkley, Iris Leng, Margie J. Bailey, Denise K. Houston, Christina E. Hugenschmidt, Barbara J. Nicklas, and W. Gregory Hundley August 2, 2021, edition.
DOI: 10.1161 / CIRKULATIONAHA.120.051943
Co-authors are Iris Leng, Ph.D .; Margie J. Bailey, MS; Denise K. Houston, Ph.D., RD; Christina E. Hugenschmidt, Ph.D .; Barbara J. Nicklas, Ph.D .; and W. Gregory Hundley, MD The authors reported no disclosures.
The study was funded by grants from the National Institutes of Health, the Wake Forest Claude D. Pepper Older Americans Independence Center, and the American Heart Association.