Weight loss, exercise or both and cardiometabolic risk factors in obese older adults: results of a randomized controlled trial

Abstract

Background Obesity exacerbates the age-related decline in insulin sensitivity and is associated with risk for cardiometabolic syndrome in older adults; however, the appropriate treatment for obese older adults is controversial. Objective To determine the independent and combined effects of weight loss and exercise on cardiometabolic risk factors in obese older adults. Design One-hundred-seven obese (BMI≥30 kg/m2) older (≥65 yrs) adults with physical frailty were randomized to control group, diet group, exercise group, and diet-exercise group for 1 year. Outcomes for this study included change in insulin sensitivity index (ISI), glucose tolerance, central obesity, adipocytokines, and cardiometabolic syndrome. Results Although similar increases in ISI occurred in the diet-exercise and diet groups at 6 months, the ISI improved more in the diet-exercise than in the diet group at 12 months (2.4 vs. 1.2; between-group difference, 1.2; 95% CI, 0.2-2.1); no changes in ISI occurred in both exercise and control groups. The diet-exercise and diet groups had similar improvements in insulin area under the curve (AUC) (−2.9 and −2.9 ×103mg.min/dl), glucose AUC (−1.4 and −2.2×103mg.min/dl), visceral fat (−787 and −561 cm3), tumor-necrosis factor (−17.0 and −12.8 pg/mL), adiponectin (5.0 and 4.0 ng/mL), waist circumference (−8.2 and −8.4 cm), triglyceride (−30.7 and −24.3 g/dL), and systolic/diastolic BP (−15.9 and −13.1/−4.9 and −6.7 mmHg), while no changes in these parameters occurred in both exercise and control groups. The cardiometabolic syndrome prevalence decreased by 40% in the diet-exercise and by 15% in the diet group. Body weight decreased similarly in the diet-exercise and diet groups (−8.6 and −9.7kg) but not in the exercise and control groups. Conclusions In frail, obese older adults, lifestyle interventions associated with weight loss improve insulin sensitivity and other cardiometabolic risk factors, but continued improvement in insulin sensitivity is only achieved when exercise training is added to weight loss.

The Effect of Regular Aerobic Training on Tumor Necrosis Factor-Alpha (TNF-α) in Males With Type II Diabetes

“…Although some previous studies have alluded to a significant reduction in TNF-α and other inflammatory cytokines in response to long-term training programs (26)(27)(28), yet in line with the present study, some recent studies have reported no change in this inflammatory cytokine following long-term training program in healthy or sick obese individuals (29,30). For example, in one study, a 12-month exercise program did not lead to changes in TNF-α, adiponectin and triglyceride levels in obese subjects (31). Furthermore, findings of a recent study showed 16 weeks of rapid walking led to an increase in serum levels of TNF-α in the absence of change in IL-6 and adiponectin in obese and overweight individuals (32).…”

Insulin Responsiveness in Metabolic Syndrome after Eight Weeks of Cycle Training

“…Villareal and coworkers at Washington University evaluated diet-induced weight loss, exercise alone, and exercise with weight loss in older obese subjects in a program to reduce frailty (5, 35). The duration of the study was one year with the exercise being combined aerobic and strength training.…”

Effect of aerobic exercise on blood lipid and glucose in obese or overweight adults: A meta-analysis of randomised controlled trials

“…For further verifying the metabolic effect of aerobic exercise in obese or overweight individuals, many randomised controlled trials (RCTs) have been performed and assessed the effect of AE on blood lipid and glucose levels [17][18][19][20]. Although a previous meta-analysis has reported the effect of AE on blood lipids in overweight and obese adults [21], the controversy still exists among some recent studies [20,22,23]. Thus, we performed this updated meta-analysis to further confirm the effect of AE on levels of blood lipid and glucose indexes in obese and overweight people.…”