This study compared the efficacy of the Curves(R) Complete 90-day Challenge (CC), Weight Watchers(R) Points Plus (WW), Jenny Craig(R) At Home (JC), and Nutrisystem(R) Advance Select(TM) (NS) on weight loss, body composition and/or markers of health and fitness in sedentary overweight women. One hundred thirty-three women (47+-11 yr, 86+-14 kg, 46+-5%, 35.4+-6 kg/m2) were randomized into CC (n=29), WW (n=29), JC (n=27), NS (n=28), or control (n=20) for 12-wks. Self-recorded food logs (4-d), International Physical Activity Questionnaires, weight, resting energy expenditure (REE), dual energy x-ray absorptiometry, anthropometrics, and fasting blood samples were obtained at 0, 4, 8, & 12 wks. Peak aerobic capacity and muscular strength were measured at 0 and 12 wks. Data were analyzed by ANOVA or MANOVA with repeated measures. Average energy intake was 1,403+-427 kcal/day with no differences among groups. CC was the only group with an increase in protein (0.15+-0.30, p=0.039) combined with a reduction in carbohydrate (-0.63+-0.95 g/kg/day, p=0.005) intake. CC was the only group with a significant increase in total physical activity (3,801+-8,668 MET-min/wk, p=0.012) through week 8. All diet groups experienced a decrease in weight (-4.0+-4.2 kg, p<0.001), body mass index (-4.0+-2.1 kg/m2, p<0.001), waist circumference (-2.7+-5.9, p<0.001), and hip circumference (-3.4+-4.4 cm, p<0.001), and all maintained REE (0.09+-2.0 kcal/kg/day, p=0.008). CC had the greatest decrease in fat mass (-3.8+-4.0 kg, p<0.001) and body fat % (-2.7+-3.4%, p<0.001) and was the only group that maintained fat-free mass (-0.19+-2.00 kg, p=0.631). All groups, except WW, had a decrease in resting heart (-3.0+-9.8 bpm, p<0.001). CC was the only group with a decrease in systolic (-7.6+-14.2, p=0.002) and diastolic blood pressure (-3.6+-7.3 mmHg, p=0.045). CC had the greatest increase in peak aerobic capacity (2.5+-2.9 ml/kg/min, p<0.001) and was the only diet group that increased in lower (15.0+-21.9 p=0.001) and upper body (8.7+-12.5% p=0.001) strength. CC trended toward a decrease in total cholesterol to HDL-cholesterol ratio (-4.9+-11.3%, p=0.053). Though all diet groups lost weight and had improvements in anthropometrics, CC experienced greater improvements in body composition, blood pressure, peak aerobic capacity, and muscular strength and trended toward improvements in blood lipid ratios.
