Maryann Ludlow

High-Calorie-Expenditure Exercise A New Approach to Cardiac Rehabilitation for Overweight Coronary Patients

Background— More than 80% of patients entering cardiac rehabilitation (CR) are overweight, and >50% have metabolic syndrome. Current CR exercise protocols result in little weight loss and minimal changes in cardiac risk factors. We sought to design an exercise protocol that would lead to greater weight loss and risk factor change. Methods and Results— We performed a randomized controlled clinical trial to evaluate the effect of high-calorie-expenditure exercise (3000- to 3500-kcal/wk exercise-related energy expenditure) compared with standard CR exercise (7 to 800 kcal/wk) on weight loss and risk factors in 74 overweight patients with coronary heart disease. Both groups were counseled for weight loss and taking evidence-based preventive medications. High-calorie-expenditure exercise resulted in double the weight loss (8.2±4 versus 3.7±5 kg; P<0.001) and fat mass loss (5.9±4 versus 2.8±3 kg; P<0.001) and a greater waist reduction (−7±5 versus −5±5 cm; P=0.02) than standard CR exercise at 5 months. High-calorie-expenditure exercise reduced insulin resistance, measured with the euglycemic hyperinsulinemic clamp, along with the ratio of total to high-density lipoprotein cholesterol and components of the metabolic syndrome, more than standard CR exercise (each P<0.01). Overall, fat mass loss best predicted improved metabolic risk, and the prevalence of metabolic syndrome decreased from 59% to 31%. Changes in cardiac risk factors included decreased insulin resistance, increased high-density lipoprotein cholesterol, and decreased measures of insulin, triglycerides, blood pressure, plasminogen activator inhibitor-1, and the ratio of total to high-density lipoprotein cholesterol (each P<0.05). Significant weight loss was maintained at 1 year. Conclusion— High-calorie-expenditure exercise promotes greater weight loss and more favorable cardiometabolic risk profiles than standard CR for overweight coronary patients.Background Over 80% of patients entering cardiac rehabilitation (CR) are overweight and >50% have metabolic syndrome. Current CR exercise protocols result in little weight loss and minimal changes in cardiac risk factors. We sought to design an exercise protocol that would lead to greater weight loss and risk factor change.

The Effect of Weight Loss and Exercise Training on Flow-Mediated Dilatation in Coronary Heart Disease : A Randomized Trial

BACKGROUND More than 80% of patients entering cardiac rehabilitation are overweight, with a high prevalence of associated insulin resistance, diabetes, hypertension, hyperlipidemia, and a prothrombotic state. Because each of these characteristics is associated with abnormalities of endothelial-dependent flow-mediated dilatation (FMD), a predictor of long-term prognosis in patients with coronary heart disease (CHD), we assessed the effect of exercise training and weight reduction on FMD in overweight patients with CHD. METHODS All patients (N = 38) participated in behavioral weight loss while taking their usual preventive medications. Subjects were randomized to one of two exercise protocols, which differed by caloric expenditure. The primary outcome was extent (%) of brachial artery FMD measured by ultrasonography before and after the 4-month exercise and weight-loss program. RESULTS Both study groups experienced an increase in brachial artery FMD after weight loss and exercise. Patients randomized to the higher-caloric exercise condition (longer-distance walking) lost more weight (8.6 ± 4.1 kg vs 2.3 ± 3.3 kg [P < .001]) and experienced a greater percentage increase in brachial artery FMD (3.6% ± 4.1% vs 1.3% ± 2.1%, P < .05) than did subjects in the lower-caloric-expenditure exercise group who lost less weight. Both groups increased peak aerobic capacity similarly. Increased FMD correlated with changes in body weight more than with measures of abdominal fat, glucose disposal, lipid measure, BP, or measures of physical activity or cardiorespiratory fitness. CONCLUSIONS Exercise and weight loss increased FMD in overweight and obese patients with CHD. Greater weight reduction was associated with a greater improvement in FMD; thus, there was a dose effect. TRIAL REGISTRY ClinicalTrials.gov; No.: NCT00628277; URL: www.clinicaltrials.gov.

The influence of obesity and consequent insulin resistance on coronary risk factors in medically treated patients with coronary disease

Objective:Obesity promotes the development and progression of coronary heart disease (CHD), in part, through its association with hyperlipidemia, hypertension, clotting abnormalities and insulin resistance. We assessed whether these relationships persist in patients with established CHD treated with evidence-based preventive pharmacologic therapies.Design and subjects:We performed a cross-sectional study of 74 adults with CHD and a body mass index (BMI) of >27 kg m–2 (mean 32±4). The mean age of subjects was 64±9 years (range 44–84 years).Measurements:Obesity measures included weight, BMI, waist, fat mass, intra-abdominal fat and subcutaneous fat. Risk factor measures included insulin sensitivity, fasting insulin level, lipid profiles, blood pressure, C-reactive protein (hs-CRP), plasminogen activator inhibitor (PAI-1) and platelet reactivity. Medication use included aspirin (99%), statin (84%), β-blocker (71%), ACE inhibitor or blocker (37%) and clopidogrel (28%).Results:There was no direct relationship between obesity parameters and risk factor measures of lipid concentrations, blood pressure, clotting abnormalities or platelet reactivity except for a modest relationship between visceral fat and hs-CRP (r=0.30, P=0.02). However, increased BMI, waist circumference, fat mass, total abdominal fat and abdominal subcutaneous fat all correlated with insulin sensitivity (r-values −0.30 to −0.45, P-values 0.01 to <0.001) and insulin concentrations. Insulin sensitivity, in turn, was the best predictor of PAI-1, triglycerides, high-density lipoprotein (HDL) levels, cholesterol/HDL levels (all P<0.01) and platelet reactivity (R=0.34, P=0.02).Conclusions:Use of preventive pharmacologic therapies obviated the expected relationship between adiposity and CHD risk factors. However, a residual effect of insulin resistance is left untreated. Total adiposity and central adiposity were strong predictors of insulin sensitivity, which in turn predicted cardiac risk factors such as lipid concentrations, PAI-1 and platelet reactivity. Thus, while evidence-based pharmacologic treatments may diminish the statistical relationship between obesity and many cardiac risk factors, adiposity negatively impacts CHD risk by reducing tissue insulin sensitivity.

Effect of exercise training and weight loss on platelet reactivity in overweight patients with coronary artery disease.

PURPOSE: Obesity is associated with increased platelet reactivity. Greater platelet reactivity presages adverse events in patients with coronary artery disease (CAD). We investigated whether exercise training and weight loss reduce platelet reactivity in overweight subjects with CAD. METHODS: Study subjects (N = 46) were enrolled in a prospective randomized study of exercise training and behavioral weight loss, which contrasted the amount of exercise performed (750 vs >3000 kcal/week). Platelet reactivity was assessed with the use of flow cytometry as the percentage of platelets expressing P-selectin or capable of binding fibrinogen in response to 1 &mgr;M adenosine diphosphate in blood before and after a 4-month program of exercise and behavioral weight loss. Markers of inflammation (high-sensitivity C-reactive protein), procoagulant activity (tissue plasminogen activator, plasminogen activator inhibitor 1), insulin sensitivity, body composition, physical activity, and fitness were also recorded. RESULTS: Platelet reactivity as assessed by P-selectin expression was decreased after exercise training and weight loss in study participants (from 34 ± 17% to 29 ± 17%; P = .01). The decrease was more pronounced in women (by 13% vs 2% in men; P < .01). The change in platelet reactivity was not independently associated with measures of body composition or fitness. After controlling for exercise group and gender, the change in platelet reactivity was associated with changes in high-sensitivity C-reactive protein (r = 0.46) and insulin sensitivity (r = 0.46). CONCLUSIONS: In overweight patients with CAD, exercise training and weight loss are associated with a decrease in platelet reactivity that may predict an improved prognosis.

Change of energy expenditure from physical activity is the most powerful determinant of improved insulin sensitivity in overweight patients with coronary artery disease participating in an intensive lifestyle modification program.

The objective was to evaluate the determinants of change (Δ) in insulin sensitivity in overweight coronary artery disease male patients without diabetes after an intensive lifestyle intervention. All patients received nutritional counseling and performed 4 months of exercise training (ET) according to 1 of 2 protocols: aerobic ET (65%-70% of peak aerobic capacity [VO(2)]) 25 to 40 minutes 3 times a week (n = 30) or walking (50%-60% of peak VO(2)) 45 to 60 minutes at least 5 times a week (n = 30). Data from participants of both ET groups were pooled, and post-intensive lifestyle intervention results were compared with baseline data. The primary outcome was Δ insulin sensitivity (m-value) assessed by the criterion standard technique, the euglycemic-hyperinsulinemic clamp. Changes in weight, body mass index, total and percentage fat mass (by dual-energy x-ray absorptiometry scan), waist circumference, total abdominal and visceral fat (by computed tomographic scan), high-sensitivity C-reactive protein, peak VO(2), daily energy intake, and physical activity energy expenditure (PAEE) (by doubly labeled water technique) were also assessed. Daily energy intake decreased by 335 kcal, and PAEE increased by 482 kcal/d (all P < .0001). The mean weight loss was 6.4 kg, and the mean improvement in m-value was 1.6 mg/kg fat-free mass per minute. Univariate determinants of Δ m-value were low baseline PAEE, walking protocol, Δ weight, Δ body mass index, Δ total and percentage fat mass, Δ waist circumference, Δ total abdominal and visceral fat, and Δ PAEE (all P < .05). In multivariate analysis, the only significant determinant of Δ m-value was Δ PAEE (P < .02). In this analysis, the most powerful determinant of improved insulin sensitivity in overweight coronary artery disease patients is the change in PAEE.

High-Calorie-Expenditure Exercise

Background— More than 80% of patients entering cardiac rehabilitation (CR) are overweight, and >50% have metabolic syndrome. Current CR exercise protocols result in little weight loss and minimal changes in cardiac risk factors. We sought to design an exercise protocol that would lead to greater weight loss and risk factor change. Methods and Results— We performed a randomized controlled clinical trial to evaluate the effect of high-calorie-expenditure exercise (3000- to 3500-kcal/wk exercise-related energy expenditure) compared with standard CR exercise (7 to 800 kcal/wk) on weight loss and risk factors in 74 overweight patients with coronary heart disease. Both groups were counseled for weight loss and taking evidence-based preventive medications. High-calorie-expenditure exercise resulted in double the weight loss (8.2±4 versus 3.7±5 kg; P<0.001) and fat mass loss (5.9±4 versus 2.8±3 kg; P<0.001) and a greater waist reduction (−7±5 versus −5±5 cm; P=0.02) than standard CR exercise at 5 months. High-calorie-expenditure exercise reduced insulin resistance, measured with the euglycemic hyperinsulinemic clamp, along with the ratio of total to high-density lipoprotein cholesterol and components of the metabolic syndrome, more than standard CR exercise (each P<0.01). Overall, fat mass loss best predicted improved metabolic risk, and the prevalence of metabolic syndrome decreased from 59% to 31%. Changes in cardiac risk factors included decreased insulin resistance, increased high-density lipoprotein cholesterol, and decreased measures of insulin, triglycerides, blood pressure, plasminogen activator inhibitor-1, and the ratio of total to high-density lipoprotein cholesterol (each P<0.05). Significant weight loss was maintained at 1 year. Conclusion— High-calorie-expenditure exercise promotes greater weight loss and more favorable cardiometabolic risk profiles than standard CR for overweight coronary patients.Background Over 80% of patients entering cardiac rehabilitation (CR) are overweight and >50% have metabolic syndrome. Current CR exercise protocols result in little weight loss and minimal changes in cardiac risk factors. We sought to design an exercise protocol that would lead to greater weight loss and risk factor change.

High-Caloric Expenditure Exercise: A New Approach to Cardiac Rehabilitation for Overweight Coronary Patients Ades: High-Caloric Exercise Overweight Coronary Patients

Background— More than 80% of patients entering cardiac rehabilitation (CR) are overweight, and >50% have metabolic syndrome. Current CR exercise protocols result in little weight loss and minimal changes in cardiac risk factors. We sought to design an exercise protocol that would lead to greater weight loss and risk factor change. Methods and Results— We performed a randomized controlled clinical trial to evaluate the effect of high-calorie-expenditure exercise (3000- to 3500-kcal/wk exercise-related energy expenditure) compared with standard CR exercise (7 to 800 kcal/wk) on weight loss and risk factors in 74 overweight patients with coronary heart disease. Both groups were counseled for weight loss and taking evidence-based preventive medications. High-calorie-expenditure exercise resulted in double the weight loss (8.2±4 versus 3.7±5 kg; P<0.001) and fat mass loss (5.9±4 versus 2.8±3 kg; P<0.001) and a greater waist reduction (−7±5 versus −5±5 cm; P=0.02) than standard CR exercise at 5 months. High-calorie-expenditure exercise reduced insulin resistance, measured with the euglycemic hyperinsulinemic clamp, along with the ratio of total to high-density lipoprotein cholesterol and components of the metabolic syndrome, more than standard CR exercise (each P<0.01). Overall, fat mass loss best predicted improved metabolic risk, and the prevalence of metabolic syndrome decreased from 59% to 31%. Changes in cardiac risk factors included decreased insulin resistance, increased high-density lipoprotein cholesterol, and decreased measures of insulin, triglycerides, blood pressure, plasminogen activator inhibitor-1, and the ratio of total to high-density lipoprotein cholesterol (each P<0.05). Significant weight loss was maintained at 1 year. Conclusion— High-calorie-expenditure exercise promotes greater weight loss and more favorable cardiometabolic risk profiles than standard CR for overweight coronary patients.Background Over 80% of patients entering cardiac rehabilitation (CR) are overweight and >50% have metabolic syndrome. Current CR exercise protocols result in little weight loss and minimal changes in cardiac risk factors. We sought to design an exercise protocol that would lead to greater weight loss and risk factor change.