THE EFFECTIVENESS OF A COMPUTER AND INTERNET-BASED SYSTEM IN A SHORT-TERM BEHAVIORAL WEIGHT LOSS INTERVENTION

THE EFFECTIVENESS OF A COMPUTER AND INTERNET-BASED SYSTEM IN A SHORT-TERM BEHAVIORAL WEIGHT LOSS INTERVENTIONKristen M. Polzien, PhD.University of Pittsburgh, 2005Computer and Internet-assisted weight loss interventions offer alternative delivery channels that might increase program appeal and potentially increase weight loss success. To date research focused on these innovative techniques is limited. PURPOSE: To examine the effectiveness adding a technology-based intervention component to an in-person, 12-week clinically-based behavioral weight loss intervention. METHODS: Fifty-seven subjects (body mass index = 33.1+/-2.8 kg/m2; age = 41.3+/-8.7 yrs) participated in a 12-week intervention with random assignment to Standard Behavioral Program (SBWP), Intermittent Technology-Based Program (INT-TECH), or Continuous Technology-Based Program (CON-TECH). SBWP received an individual weight loss session at weeks 1-4, 6, 8, and 10, prescribed a diet of 1200-1500 kcal/d, and exercise progressing from 20-40 min/d on 5 days/wk. INT-TECH and CON-TECH received the components of SBWP, however, these groups also used a SenseWear Pro Armband (BodyMedia, Inc.) to monitor energy expenditure and a web-based program to monitor eating behaviors. INT-TECH used these features during weeks 1, 5, and 9, with CON-TECH using these features throughout the 12-week intervention. Outcomes included body weight, percent body fat, and cardiorespiratory fitness. RESULTS: Fifty subjects completed the investigation (88%). Intent-to-treat analysis revealed weight loss of 4.1+/-2.8 kg (4.6 +/-2.8%), 3.4+/-3.4 kg (3.8+/-3.8%), and 6.2+/-4.0 kg (7.1+/-4.6%), for the SBWP, INT-TECH, and CON-TECH groups, respectively (CON-TECH greater than INT-TECH, p less than/equal to 0.05). Percent body fat was significantly decreased in CON-TECH (-4.1+/-2.9%) when compared to both SBWP (-1.6+/-1.5%) and INT-TECH (-1.6+/-1.7%) (p less than/equal to 0.05). Cardiorespiratory fitness significantly increased in all groups by 14%, 3%, and 5% in SBWP, INT-TECH, and CON-TECH, respectively; p less than 0.01), with no significant group differences. CONCLUSIONS: Results indicate that a technology-based program that is used continuous over a 12-week intervention and is complimentary to a clinically-based in-person intervention improves weight loss by approximately 3% compared to a SBWP that does not use these technology features or by approximately 3.7% compare to INT-TECH uses the technology features only intermittently during the intervention. Considering these short-term results, future studies should examine the impact of adding these technology features to a SBWP on long-term weight loss outcomes, and for whom technology-based programs are most effective

The effect of self-efficacy on behavior and weight in a behavioral weight-loss intervention.

To determine whether eating self-efficacy and physical activity self-efficacy are predictive of dietary intake, physical activity, and weight change within a behavioral weight loss intervention, and whether dietary intake and physical activity mediate relationships between self-efficacy and weight change

The Effect of Physical Activity on 18-Month Weight Change in Overweight Adults

Few studies have been conducted that have examined the long-term effect of different doses of physical activity (PA) on weight change in overweight adults without a prescribed reduction in energy intake. This study examined the effect of different prescribed doses of PA on weight change, body composition, fitness and PA in overweight adults. 278 overweight adults (BMI: 25.0 to 29.9 kg/m2; Age: 18 to 55 years) with no contraindications to PA were randomized to one of three intervention groups for a period of 18 months. MOD-PA was prescribed 150 min/wk and HIGH-PA 300 min/wk of PA. SELF was provided a self-help intervention to increase PA. There was no recommendation to reduce energy intake. MOD-PA and HIGH-PA was delivered in a combination of in-person and telephone contacts across 18 months. 18-month percent weight change was −0.7±4.6% in SELF, −0.9±4.7% in MOD-PA, and −1.2±5.6% in HIGH-PA. Subjects were retrospectively grouped as remaining within ±3% of baseline weight (WT-STABLE), losing >3% of baseline weight (WT-LOSS), or gaining >3% of baseline weight (WT-GAIN) for secondary analyses. 18-month weight change was 0.0±1.3% for WT-STABLE, +5.4±2.6% for WT-GAIN, and −7.4±3.6% for WT-LOSS. 18-month change in PA was 78.2±162.6 min/wk for WT-STABLE, 74.7±274.3 for WT-GAIN, and 161.9±252.6 min/wk for WT-LOSS. The weight change observed in WT-LOSS was a result of higher PA combined with improved scores on the Eating Behavior Inventory, reflecting the adoption of eating behaviors to facilitate weight loss. Strategies to facilitate the maintenance of these behaviors are needed to optimize weight control

Randomized trial comparing group size of periodic in-person sessions in a remotely delivered weight loss intervention

Abstract Background Few randomized studies have examined differential effects of group size in behavioral weight control, especially in hybrid programs that include Internet treatment approaches. Methods Randomized controlled trial (n = 195) comparing a 4 month hybrid internet weight loss program coupled with monthly face to face groups of 100 persons (Large Group, LG; 1 group) or to the same approach with monthly groups of 20 persons (Small Group, SG; 4 groups). Repeated-measures mixed-model analysis with age and race as covariates were used to estimate primary (weight) and secondary outcomes, and to test group differences in change over time. Results The sample was 46.3 years old ±10.4, 90.3% female, and 51.9% non-white, with BMI 37.9 ± 8.4 kg/m2. Participants in the LG were more likely to return for the 4-month assessment visit than those in the SG (p = 0.04). Participants randomized to both the LG and SG conditions experienced significant WL over time (no between group difference: −4.1 kg and −3.7 kg, respectively) and weight loss was positively associated with attendance at monthly meetings and logins to the website. Satisfaction with the program was high and similar in both groups (94.4% reported that they were “satisfied” or “very satisfied”). Conclusions Using a hybrid approach of in-person and online weight loss interventions may be an effective way to reach larger and more diverse populations. Delivering the face to face component of the intervention in groups larger than those traditionally delivered (20–25 people) could increase the cost-effectiveness of group-based behavioral weight loss interventions. Clinical trials registration number NCT01615471 . Registered June 6, 2012. Registered retrospectively

Replacing caloric beverages with water or diet beverages for weight loss in adults: main results of the Choose Healthy Options Consciously Everyday (CHOICE) randomized clinical trial 1-4

ABSTRACT Background: Replacement of caloric beverages with noncaloric beverages may be a simple strategy for promoting modest weight reduction; however, the effectiveness of this strategy is not known. Objective: We compared the replacement of caloric beverages with water or diet beverages (DBs) as a method of weight loss over 6 mo in adults and attention controls (ACs). Design: Overweight and obese adults [n = 318; BMI (in kg/m 2 ): 36.3 6 5.9; 84% female; age (mean 6 SD): 42 6 10.7 y; 54% black] substituted noncaloric beverages (water or DBs) for caloric beverages (200 kcal/d) or made dietary changes of their choosing (AC) for 6 mo. Results: In an intent-to-treat analysis, a significant reduction in weight and waist circumference and an improvement in systolic blood pressure were observed from 0 to 6 mo. Mean (6SEM) weight losses at 6 mo were 2.5 6 0.45% in the DB group, 2.03 6 0.40% in the Water group, and 21.76 6 0.35% in the AC group; there were no significant differences between groups. The chance of achieving a 5% weight loss at 6 mo was greater in the DB group than in the AC group (OR: 2.29; 95% CI: 1.05, 5.01; P = 0.04). A significant reduction in fasting glucose at 6 mo (P = 0.019) and improved hydration at 3 (P = 0.0017) and 6 (P = 0.049) mo was observed in the Water group relative to the AC group. In a combined analysis, participants assigned to beverage replacement were 2 times as likely to have achieved a 5% weight loss (OR: 2.07; 95% CI: 1.02, 4.22; P = 0.04) than were the AC participants. Conclusions: Replacement of caloric beverages with noncaloric beverages as a weight-loss strategy resulted in average weight losses of 2% to 2.5%. This strategy could have public health significance and is a simple, straightforward message. This trial was registered at clinicaltrials.gov as NCT01017783. Am J Clin Nutr 2012;95:555-63

Randomized trial comparing group size of periodic in-person sessions in a remotely delivered weight loss intervention

Abstract Background Few randomized studies have examined differential effects of group size in behavioral weight control, especially in hybrid programs that include Internet treatment approaches. Methods Randomized controlled trial (n = 195) comparing a 4 month hybrid internet weight loss program coupled with monthly face to face groups of 100 persons (Large Group, LG; 1 group) or to the same approach with monthly groups of 20 persons (Small Group, SG; 4 groups). Repeated-measures mixed-model analysis with age and race as covariates were used to estimate primary (weight) and secondary outcomes, and to test group differences in change over time. Results The sample was 46.3 years old ±10.4, 90.3% female, and 51.9% non-white, with BMI 37.9 ± 8.4 kg/m2. Participants in the LG were more likely to return for the 4-month assessment visit than those in the SG (p = 0.04). Participants randomized to both the LG and SG conditions experienced significant WL over time (no between group difference: −4.1 kg and −3.7 kg, respectively) and weight loss was positively associated with attendance at monthly meetings and logins to the website. Satisfaction with the program was high and similar in both groups (94.4% reported that they were “satisfied” or “very satisfied”). Conclusions Using a hybrid approach of in-person and online weight loss interventions may be an effective way to reach larger and more diverse populations. Delivering the face to face component of the intervention in groups larger than those traditionally delivered (20–25 people) could increase the cost-effectiveness of group-based behavioral weight loss interventions. Clinical trials registration number NCT01615471 . Registered June 6, 2012. Registered retrospectively