Abstract 3790: High-Caloric Energy Expenditure in Cardiac Rehabilitation: A New Paradigm for Overweight coronary patients
More than 80% of patients entering cardiac rehabilitation (CR) are overweight and >50% have metabolic syndrome. Current CR approaches to exercise and counseling result in minimal weight loss, due in part to the low total exercise-related energy expenditure of 7– 800 kcal/week. We evaluated the effect of high-caloric expenditure exercise (HCEE) on weight loss and risk factors in overweight patients with coronary heart disease (CHD) in a randomized-controlled trial comparing 4 months of HCEE with a goal of 3500 kcal/week exercise energy expenditure vs 800 kcal/week of standard CR exercise in a control group. The HCEE group gradually increased daily walking bouts to achieve 45– 60 minutes daily while the control group exercised three times weekly on the treadmill for 25 minutes per session. Both groups received behavioral weight loss counseling to achieve a dietary caloric deficit of 500 kcal/day. Medications were held steady throughout the study. At baseline mean age was 64 ± 9 years and BMI was 32 ± 4, (range 27– 45). The HCEE group (N=36) experienced double the weight loss (8 ± 4 vs. 4 ± 5 kg), fat mass loss (6 ± 4 vs. 3 ± 3kg) and a greater waist reduction (7 ± 5 vs. 5 ± 5 cm) than the low caloric exercise group (each P<0.03). The HCEE group also experienced a greater reduction in the Cholesterol / HDL-C ratio and fasting insulin, (both, p <0.01) and strong trends for greater reductions in plasminogen activator inhibitor-1 and triglycerides (both p<0.07). The combined study groups (N=72) experienced a mean weight loss of 6 ± 5 kg, a mean fat mass loss of 4 ± 4 kg and a 6 ± 5 cm reduction in waist circumference (each P<0.001). This was associated with an increase in insulin sensitivity measured by euglycemic insulin clamp (+ 21% ), reductions of triglycerides (134 ± 78 to 114 ± 61 mg/dL) , PAI-1 (− 29%), Chol/HDL ratio (4.1 ± 1.1 vs.3.7 ± 1.0), fasting insulin (− 36%) and mean blood pressure (95 ± 10 vs 87 ± 10 ) (all P<0.05), an increase in HDL-C (40 ± 10 vs 43 ± 11), a trend to lower C-Reactive Protein (P<0.07) but no change in platelet reactivity. In summary, overweight patients with CHD attending CR programs should maximize exercise-related energy expenditure to attain greater weight loss and more favorable risk profiles than are obtained with classic CR exercise protocols.