Kelliann K. Davis

Effect of Wearable Technology Combined With a Lifestyle Intervention on Long-term Weight Loss: The IDEA Randomized Clinical Trial

Importance Effective long-term treatments are needed to address the obesity epidemic. Numerous wearable technologies specific to physical activity and diet are available, but it is unclear if these are effective at improving weight loss. Objective To test the hypothesis that, compared with a standard behavioral weight loss intervention (standard intervention), a technology-enhanced weight loss intervention (enhanced intervention) would result in greater weight loss. Design, Setting, Participants Randomized clinical trial conducted at the University of Pittsburgh and enrolling 471 adult participants between October 2010 and October 2012, with data collection completed by December 2014. Interventions Participants were placed on a low-calorie diet, prescribed increases in physical activity, and had group counseling sessions. At 6 months, the interventions added telephone counseling sessions, text message prompts, and access to study materials on a website. At 6 months, participants randomized to the standard intervention group initiated self-monitoring of diet and physical activity using a website, and those randomized to the enhanced intervention group were provided with a wearable device and accompanying web interface to monitor diet and physical activity. Main Outcomes and Measures The primary outcome of weight was measured over 24 months at 6-month intervals, and the primary hypothesis tested the change in weight between 2 groups at 24 months. Secondary outcomes included body composition, fitness, physical activity, and dietary intake. Results Among the 471 participants randomized (body mass index [BMI], 25 to <40; age range, 18-35 years; 28.9% nonwhite, 77.2% women), 470 (233 in the standard intervention group, 237 in the enhanced intervention group) initiated the interventions as randomized, and 74.5% completed the study. For the enhanced intervention group, mean base line weight was 96.3 kg (95% CI, 94.2-98.5) and 24-month weight 92.8 kg (95% CI, 90.6- 95.0) [corrected]. For the standard intervention group, mean baseline weight was 95.2kg (95%CI,93.0-97.3)and24-month weight was 89.3 kg (95%CI, 87.1-91.5) [corrected]. Weight change at 24 months differed significantly by intervention group (estimated mean weight loss, 3.5 kg [95% CI, 2.6-4.5} in the enhanced intervention group and 5.9 kg [95% CI, 5.0-6.8] in the standard intervention group; difference, 2.4 kg [95% CI, 1.0-3.7]; P = .002). Both groups had significant improvements in body composition, fitness, physical activity, and diet, with no significant difference between groups. Conclusions and Relevance Among young adults with a BMI between 25 and less than 40, the addition of a wearable technology device to a standard behavioral intervention resulted in less weight loss over 24 months. Devices that monitor and provide feedback on physical activity may not offer an advantage over standard behavioral weight loss approaches. Trial Registration clinicaltrials.gov Identifier: NCT01131871.

The Comparison of a Technology-Based System and an In-Person Behavioral Weight Loss Intervention

The purpose of this study was to compare a technology‐based system, an in‐person behavioral weight loss intervention, and a combination of both over a 6‐month period in overweight adults. Fifty‐one subjects (age: 44.2 ± 8.7 years, BMI: 33.7 ± 3.6 kg/m2) participated in a 6‐month behavioral weight loss program and were randomized to one of three groups: standard behavioral weight loss (SBWL), SBWL plus technology‐based system (SBWL+TECH), or technology‐based system only (TECH). All groups reduced caloric intake and progressively increased moderate intensity physical activity. SBWL and SBWL+TECH attended weekly meetings. SBWL+TECH also received a TECH that included an energy monitoring armband and website to monitor energy intake and expenditure. TECH used the technology system and received monthly telephone calls. Body weight and physical activity were assessed at 0 and 6 months. Retention at 6 months was significantly different (P = 0.005) between groups (SBWL: 53%, SBWL+TECH: 100%, and TECH: 77%). Intent‐to‐treat (ITT) analysis revealed significant weight losses at 6 months in SBWL+TECH (−8.8 ± 5.0 kg, −8.7 ± 4.7%), SBWL (−3.7 ± 5.7 kg, −4.1 ± 6.3%), and TECH (−5.8 ± 6.6 kg, −6.3 ± 7.1%) (P < 0.001). Self‐report physical activity increased significantly in SBWL (473.9 ± 800.7 kcal/week), SBWL+TECH (713.9 ± 1,278.8 kcal/week), and TECH (1,066.2 ± 1,371 kcal/week) (P < 0.001), with no differences between groups (P = 0.25). The TECH used in conjunction with monthly telephone calls, produced similar, if not greater weight losses and changes in physical activity than the standard in‐person behavioral program at 6 months. The use of this technology may provide an effective short‐term clinical alternative to standard in‐person behavioral weight loss interventions, with the longer term effects warranting investigation.

Obesity and Physical Activity

Physical activity seems to be an important component of lifestyle interventions for weight loss and maintenance. Although the effects of physical activity on weight loss may seem to be modest, there seems to be a dose-response relationship between physical activity and weight loss. Physical activity also seems to be a critically important behavior to promote long-term weight loss and the prevention of weight regain. The benefits of physical activity on weight loss are also observed in patients with severe obesity (BMI ≥ 35 kg/m²) and in patients who have undergone bariatric surgery. Moreover, independent of the effect of physical activity on body weight, engagement in physical activity that results in improved cardiorespiratory fitness can contribute to reductions in health risk in overweight and obese adults. Thus, progression of overweight and obese patients to an adequate dose of physical activity needs to be incorporated into clinical interventions for weight control.

Short-Term Weight Loss with Diet and Physical Activity in Young Adults: the IDEA Study

This study examined the effect of a behavioral weight loss intervention (BWLI) on young adults (age = 18‐35 years).

Objective physical activity and weight loss in adults: the step-up randomized clinical trial.

To examine the amount of objectively measured MVPA and LPA that is associated with long‐term weight loss and the maintenance of clinically significant weight loss.

Reducing Sedentary Behavior Versus Increasing Moderate-to-Vigorous Intensity Physical Activity in Older Adults: A 12-Week Randomized, Clinical Trial.

Objective: To compare the effects of behavioral interventions targeting decreased sedentary behavior versus increased moderate-to-vigorous intensity physical activity (MVPA) in older adults. Method: Inactive older adults (N = 38, 68 ± 7 years old, 71% female) were randomized to 12-week interventions targeting decreased sedentary behavior (Sit Less) or increased MVPA (Get Active). The SenseWear armband was used to objectively assess activity in real time. Assessments included a blinded armband, the Community Health Activites Model Program for Senior (CHAMPS) questionnaire, 400-meter walk, and the Short Physical Performance Battery (SPPB). Results: Objectively measured MVPA increased in Get Active (75 ± 22 min/week, p < .001); self-reported MVPA increased in both groups (p < .05). Sedentary behavior did not change in either group (all p > .05). Only the Sit Less group improved the SPPB score (0.5 ± 0.3, p = .046). Discussion: Targeting reduced sedentary behavior had a greater effect on physical function among inactive but high functioning older adults over 12 weeks. Future studies of longer duration and combining increased MVPA with reduced sedentary behavior are needed.

Objective Versus Self-Reported Physical Activity in Overweight and Obese Young Adults.

BACKGROUND To compare moderate-to-vigorous intensity physical activity (MVPA) assessed via questionnaires to an objective measure of MVPA in overweight or obese young adults. METHODS MVPA was assessed in 448 [median BMI = 31.2 (Interquartile Range: 28.5-34.3) kg/m2] young adults [median age: 30.9 (Interquartile Range: 27.8-33.7) years]. Measures included the SenseWear Armband (MVPAOBJ), the Paffenbarger Questionnaire (MVPAPAFF), and the Global Physical Activity Questionnaire (GPAQ). The GPAQ was used to compute total MVPA (MVPAGPAQ-TOTAL) and MVPA from transportation and recreation (MVPAGPAQ-REC). RESULTS The association between MVPAOBJ and MVPAPAFF was rs = 0.40 (P < .0001). Associations between MVPAOBJ and MVPAGPAQ-TOTAL and MVPAGPAQ-REC were rs = 0.19 and rs = 0.32, respectively (P < .0001). MVPAGPAQ-TOTAL was significantly greater than MVPAOBJ (P < .0001). Median differences in MET-min/week between MVPAOBJ and MVPAPAFF or MVPAGPAQ-REC were not significantly different from zero. There was proportional bias between each self-reported measure of MVPA and MVPAOBJ. There were significant associations between all measures of MVPA and fitness. MVPAOBJ was significantly associated with BMI and percent body fat. CONCLUSIONS Objective and self-reported measures of MVPA are weakly to moderately correlated, with substantial differences between measures. MVPAOBJ provided predictive validity with fitness, BMI, and percent body fat. Thus, an objective measure of MVPA may be preferred to self-report in young adults.

Racial Differences in Weight Loss Among Adults in a Behavioral Weight Loss Intervention: Role of Diet and Physical Activity

BACKGROUND African-Americans lose less weight during a behavioral intervention compared with Whites, which may be from differences in dietary intake or physical activity. METHODS Subjects (30% African American, 70% White; n = 346; 42.4 ± 9.0 yrs.; BMI = 33.0 ± 3.7 kg/m2) in an 18-month weight loss intervention were randomized to a standard behavioral (SBWI) or a stepped-care (STEP) intervention. Weight, dietary intake, self-report and objective physical activity, and fitness were assessed at 0, 6, 12, and 18 months. RESULTS Weight loss at 18 months was greater in Whites (-8.74 kg with 95% CI [-10.10, -7.35]) compared with African Americans (-5.62 kg with 95% CI [-7.86, -3.37]) (P = .03) in the SBWI group and the STEP group (White: -7.48 kg with 95% CI [-8.80, -6.17] vs. African American: -4.41kg with 95% CI [-6.41, -2.42]) (P = .01). Patterns of change in dietary intake were not different between groups. Objective physical activity (PA) changed over time (P < .0001) and was higher in Whites when compared with African Americans (P = .01). CONCLUSIONS Whites lost more weight (3.10 kg) than African American adults. Although there were no differences in dietary intake, Whites had higher levels of objective PA and fitness. Thus, the discrepancy in weight loss may be due to differences in PA rather than dietary intake. However, the precise role of these factors warrants further investigation.

Objective vs. Self-report Sedentary Behavior in Overweight and Obese Young Adults

BACKGROUND Sedentary behavior (SED) has been measured almost exclusively by self-reported total SED or television time in longitudinal studies. This manuscript aimed to compare self-reported vs. objectively measured SED. METHODS Among overweight and obese young adults enrolled in a weight loss trial, baseline SED was assessed by 3 methods: 1) a questionnaire assessing 8 common SEDs (SEDQ), 2) 1 question assessing SED from the Global Physical Activity Questionnaire (SEDGPAQ), and 3) a monitor worn on the arm (SEDOBJ). In addition, television time (SEDTV) was isolated from the SEDQ. SED measures were compared using Spearmans correlations, signed-rank tests, and Bland-Altman plots. RESULTS In 448 participants, SEDQ and SEDGPAQ were only weakly associated with SEDOBJ (rs = 0.21; P < .001, rs = 0.32; P < .001, respectively). Compared with SEDOBJ, SEDQ more often overestimated SEDOBJ (median difference: 1.1 hours/day; P < .001), while SEDGPAQ more often underestimated SEDOBJ (median difference: -0.7 hours/day; P < .001). The correlation between SEDTV and SEDOBJ was not significantly different from 0 (rs = 0.08; P = .08). CONCLUSIONS SEDQ and SEDGPAQ were weakly correlated with, and significantly different from, SEDOBJ in overweight and obese young adults. SEDTV was not related to SEDOBJ. The poor associations of self-reported and objectively measured SED could affect interpretation and comparison across studies relating SED to adverse health outcomes.

Objective monitoring of physical activity in overweight and obese populations

Abstract Background: Overweight and obesity are significant public health concerns in the United States as well as worldwide. Physical activity is consistently recommended as an important lifestyle behaviour in the treatment of overweight and obesity. Objective monitoring of physical activity using portable devices may provide an enhanced understanding of the role of physical activity in body weight regulation, and these devices may prove to be effective intervention tools. Objectives: The purpose of this manuscript is to provide an overview of the effect of physical activity as a treatment modality for overweight and obesity. Moreover, this will address the methods of objective monitoring of physical activity and related energy expenditure, along with consideration of these technologies within the context of intervention programs for weight loss. Major findings: Physical activity without a reduction in energy intake appears to result in weight loss ranging from 1–3 kg. Portable multisensor devices have been shown to provide an acceptable estimate of energy expenditure resulting from physical activity. It may be beneficial to incorporate these devices and this technology within the context of weight control interventions to facilitate accurate self-monitoring of physical activity behaviour. Moreover, inclusion of these devices and technology within lifestyle interventions facilitates weight loss in overweight and obese adults. Conclusions: Physical activity is an important lifestyle behaviour in the treatment of overweight and obesity. Interventions should consider the inclusion of objective monitoring of physical activity to facilitate self-monitoring of this behaviour and to enhance physical activity participation, which appears to improve weight loss.