Obesity and low levels of physical and metabolic fitness are risk factors for cardiovascular disease and diabetes. The purpose of this investigation was to attenuate obesity and improve physical and metabolic fitness in elementary school children. Schools have the opportunity, mechanisms, and personnel in place to deliver nutrition education, fitness activities, and a school food service that is nutritious and healthy. Cohorts from grades 3 to 5 in two school districts in rural Nebraska (Intervention/Control) participated in a 2-year study of physical activity and modified school lunch program. Data collection for aerobic capacity, body composition, blood chemistry, nutrition knowledge, energy intake, and physical activity was at the beginning and end of each year. Int received enhanced physical activity, grade specific nutrition education, and a lower fat and sodium school lunch program. Con continued with a regular school lunch and team sports activity program. At year 2, Int lunches had significantly less energy (9%), fat (25%), sodium (21%), and more fiber (17%). However, measures of 24-hour energy intake for Int and Con showed significant differences for sodium only. Physical activity in the classroom was 6% greater for Int compared to Con (p < 0.05) but physical activity outside of school was approximately 16% less for Int compared to Con (p < 0.05). Body weight and body fat were not different between schools for normal weight or obese children. No differences were found for cholesterol, insulin, and glucose; however, HDL cholesterol was significantly greater and cholesterol/HDL was significantly less for Int compared to Con (p < 0.05). It appears that compensation in both energy intake and physical activity outside of school may be responsible for the lack of differences between Int and Con.

This study investigated whether the addition of the high-intensity sweetener aspartame to a multidisciplinary weight-control program would improve weight loss and long-term control of body weight. One hundred sixty-three obese women were randomly assigned to consume or to abstain from aspartame-sweetened foods and beverages during 16 wk of a 19-wk weight-reduction program (active weight loss), a 1-y maintenance program, and a 2-y follow-up period. Women in both treatment groups lost approximately 10% of initial body weight (10 kg) during active weight loss. Among women assigned to the aspartame-treatment group, aspartame intake was positively correlated with percentage weight loss during active weight loss (r = 0.32, P < 0.01). During maintenance and follow-up, participants in the aspartame group experienced a 2.6% (2.6 kg) and 4.6% (4.6 kg) regain of initial body weight after 71 and 175 wk, respectively, whereas those in the no-aspartame group gained an average of 5.4% (5.4 kg) and 9.4% (9.4 kg), respectively. The aspartame group lost significantly more weight overall (P = 0.028) and regained significantly less weight during maintenance and follow-up (P = 0.046) than did the no-aspartame group. Percentage weight losses at 71 and 175 wk were also positively correlated with exercise (r = 0.32, P < 0.001; and r = 0.34, P < 0.01, respectively) and self-reported eating control (r = 0.37, P < 0.001; and r = 0.33, P < 0.01, respectively). These data suggest that participation in a multidisciplinary weight-control program that includes aspartame may facilitate the long-term maintenance of reduced body weight.

Effects of large (LA; 400 min/wk) and moderate (MA; 200 min/wk) amounts of endurance exercise in combination with weight training (3 d/wk) were compared with the effects of no exercise (C) in 23 obese females after a 12-wk, 3360-kJ/d very-low-energy diet (VLED). The LA group lost 6.5 kg more weight, mainly as fat (6.4 kg), than the C group (P < 0.05). No measurable differences were found among groups for decreases in resting metabolic rate (-729 to -1233 kJ/d; NS) or fat-free mass (-2.9 to -3.9 kg; NS). No improvements in aerobic capacity were achieved with the addition of exercise to a VLED (-0.079 to -0.037 L/min; NS). Strength indexes were improved (+16 to +5 kg; P < 0.05) or maintained with exercise (-3 kg; NS) whereas a loss (-9.3 kg; P < 0.05) or maintenance (+4.5 kg; NS) was found for VLED alone. Large amounts of endurance exercise in combination with weight training added to a VLED appear to improve weight and fat loss compared with a VLED alone.

The combined effects of exercise and energy restriction on changes in body fat and fat-free mass (FFM) are controversial. This study was conducted to determine whether muscle hypertrophy is possible during weight loss. Fourteen obese females received a 3360-kJ/d liquid diet for 90 d. Seven subjects received a weight training (WT) regimen and seven subjects remained sedentary (C). Biopsy samples were obtained from the vastus lateralis muscle at baseline and after 90 d of treatment. The average weight loss over the 90-d period was 16 kg with approximately 24% of the weight loss from FFM and 76% from fat. The amount and composition of the weight loss did not differ between WT and C groups. The cross-sectional area of slow twitch and fast twitch fibers was unchanged by treatment in C subjects but significantly increased in WT subjects. It appears that weight training can produce hypertrophy in skeletal muscle during severe energy restriction and large-scale weight loss.