OBJECTIVE: The therapeutic effectiveness of diet, exercise, and diet plus exercise for weight loss in obesity was determined. DATA SOURCES: All human research reported in English, published in peer-reviewed scienti®c journals within the past 25 y was reviewed. STUDY SELECTION: Acceptance criteria (n 493 from b 700 studies) were that a therapeutic intervention of diet, exercise or diet plus exercise was employed, speci®cally for weight reduction in obese adult humans and that weight change was reported numerically. Only aerobic exercise studies were included, while drug, hormone and surgical treatments were excluded. DATA EXTRACTION: All data were extracted by the same investigator from the original research report. Except for gender and program type, all extracted data were numerical. DATA SYNTHESIS: ANOVA, with a Newman±Keuls post hoc test, was used to determine differences among programs (P`0.05). One analysis was performed on the group mean data and one based on effect sizes. Analyses were repeated using initial body weight, initial percent body fat and program length, as covariates. RESULTS: Primarily, subjects aged 40 y have been studied (39.5 AE 0.4 y, mean AE s.e.m.) who are only moderately obese (92.7 AE 0.9 kg, 33.2 AE 0.5 body mass index (BMI), 33.4 AE 0.7% body fat); for short durations (15.6 AE 0.6 weeks). Exercise studies were of a shorter duration, used younger subjects who weighed less, had lower BMI and percentage body fat values, than diet or diet plus exercise studies. Despite these differences, weight lost through diet, exercise and diet plus exercise was 10.7 AE 0.5, 2.9 AE 0.4* and 11.0 AE 0.6 kg, respectively. However, at one-year follow-up, diet plus exercise tended to be the superior program. Effect size and covariate analyses revealed similar program differences. CONCLUSION: Weight loss research over the past 25 y has been very narrowly focused on a middle age population that is only moderately obese, while the interventions lasted for only short periods of time. The data shows, however, that a 15-week diet or diet plus exercise program, produces a weight loss of about 11 kg, with a 6.6 AE 0.5 and 8.6 AE 0.8 kg maintained loss after one year, respectively.

The purpose of this study was to evaluate the effect of rapid weight loss on static balance and functional mobility among excessively obese patients undergoing Laparoscopic Adjustable Gastric Banding (LAGB) surgery. Subjects (8 females; BMI >35 kg/m2) underwent baseline measurements before LAGB surgery, followed by subsequent evaluations at 6 weeks, 12 weeks, and 24 weeks during the follow-up appointments. During each evaluation, various assessments were conducted, including measurements of anthropometry such as body weight, height, hip and waist circumference, as well as functional tests for static balance, 10-meter walk, and timed get-up-and-go. There were statistically significant changes in weight, BMI, waist circumference, hip circumference, abdominal circumference, waist-hip ratio, static sway eyes open, timed up-and-go, 10-meter walk, and steps in 10-meter walk test values (p<0.001) between the baseline and the postoperative measurements. However static sway values under eyes closed condition were not statistically significant. In the 24-week follow-up, the weight loss, reduction in abdominal circumference, increase in walking speed against time and step count, and recovery in functional movements were shown to persist. Also, reduction in static balance surface oscillation confirmed the improvement of balance control.

Background: Falling is a major cause of disability and death among elderly people. Therefore, a clear understanding of fall mechanism is necessary for providing preventative and treatment methods. Several fall simulation protocols have been introduced to study lost of balance in a laboratory setting. New Method We have explained and examined a new method to induce a sudden perturbation on standing posture to provide an insight into the mechanism of falling. The method comprises eliciting an H-reflex protocol while subjects are standing which produces a contraction in soleus and gastrocnemius muscles. We have also defined analytical techniques to provide biomarkers of balance control during perturbation. The method is easy to implement and interpret. The H-reflex or M-wave can be elicited unilaterally or bilaterally causing a forward or sideway perturbation. The vector analysis and the Equilibrium Point calculations defined here can quantify the amplitude, direction, and evolution of the perturbation. Results We tested this method on a group of healthy individuals and observed clear patterns of loss of balance due to stimulation. Direction and magnitude of deviation was manifested through the reconstructed vectors, with bilateral stimulation causing the largest perturbation. Comparison and conclusion The resultant plantarflexion torque is reminiscent of tripping over an obstacle and triggers corrective reactions to restore balance. Therefore, it is more similar to an internal perturbation. Mechanical perturbations to the torso cause a displacement in center of mass (COM) and trigger a cascade of mechanisms. Our method, does not trigger the perturbation by the displacement of COM initially and therefore, triggers fewer mechanisms for regaining balance.