Severe obesity is characterized by low physical activity (PA) and interventions to enhance PA are needed. Participants (45.0 ± 3.9？kg/m2) were randomized to a 6-month standard behavioral weight loss program (SBWL; n = 14) or SBWL+technology (SBWL+TECH; n = 15). Both groups received identical SBWL treatment and SBWL+TECH also received a wearable PA monitor, providing “real-time” feedback, and website access to monitor energy balance. 6-month retention was similar between groups (SBWL: 12/13 versus SBWL+TECH: 11/14 completers; P = 0.19) and adherence to wearing the armband was excellent (91.3% of days). Although differences in PA between groups did not meet conventional thresholds of significance, SBWL+TECH increased their moderate-to-vigorous intensity PA by 132.9 ± 216.8 min/week, which was 3 times greater than SBWL (44.8 ± 124.3 min/week; P = 0.27; Cohen’s d = 0.50). There was a trend for SBWL+TECH to self-monitor for a greater proportion of days compared to SBWL (86.2 ± 21.4% versus 71.5 ± 19.4%; P = 0.098; Cohen’s d = 0.72). The difference in weight loss between groups was modest (SBWL+TECH: ？10.0 ± 7.1% versus SBWL: ？7.8 ± 6.7%; P = 0.46). These preliminary findings suggest that PA monitors may be one strategy for increasing PA among the severely obese. Larger, long-term trials are needed. 1. Introduction Severe obesity (BMI 40？kg/m2), a rapidly rising subgroup of the obese population, is associated with increased risk for cardiovascular disease (CVD) and all-cause mortality [1, 2]. While the majority of clinical trials have focused on examining the efficacy of bariatric surgery, pharmacotherapy, or residential treatment camps, recently there has been a renewed interest in standard behavioral weight loss (SBWL) programs for treating the severely obese [3]. Two recent studies suggest that SBWL programs for the severely obese produce significant 1-year weight losses and improvements in CVD risk factors, similar to their less obese peers [4, 5]. However, individuals with severe obesity report less physical activity (PA) both before and after the intervention [5]. This is of concern given the importance of PA on health outcomes [6, 7] and weight maintenance [8, 9]. Therefore, it is necessary to develop methods for increasing PA in this population, which if sustained over time, could favorably impact body weight. One strategy for improving PA within SBWL treatment is through the use of wearable PA monitors. These monitors provide “real-time” PA and energy-expenditure feedback and are believed to improve energy balance awareness and reduce the burden of
References
[1]
K. M. Flegal, M. D. Carroll, B. K. Kit, and C. L. Ogden, “Prevalence of obesity and trends in the distribution of body mass index among US adults, 1999-2010,” Journal of the American Medical, vol. 307, pp. 491–497, 2012.
[2]
K. McTigue, J. C. Larson, A. Valoski et al., “Mortality and cardiac and vascular outcomes in extremely obese women,” Journal of the American Medical Association, vol. 296, no. 1, pp. 79–86, 2006.
[3]
G. L. Blackburn, S. Wollner, and S. B. Heymsfield, “Lifestyle interventions for the treatment of class III obesity: a primary target for nutrition medicine in the obesity epidemic,” American Journal of Clinical Nutrition, vol. 91, pp. 289S–292S, 2010.
[4]
B. H. Goodpaster, J. P. DeLany, A. D. Otto et al., “Effects of diet and physical activity interventions on weight loss and cardiometabolic risk factors in severely obese adults: a randomized trial,” Journal of the American Medical Association, vol. 304, no. 16, pp. 1795–1802, 2010.
[5]
J. L. Unick, D. Beavers, J. M. Jakicic, A. E. Kitabchi, W. C. Knowler, T. A. Wadden, et al., “Effectiveness of lifestyle interventions for individuals with severe obesity and type 2 diabetes: results from the Look AHEAD trial,” Diabetes Care, vol. 34, pp. 2152–2157, 2011.
[6]
M. Wei, J. B. Kampert, C. E. Barlow et al., “Relationship between low cardiorespiratory fitness and mortality in normal-weight, overweight, and obese men,” Journal of the American Medical Association, vol. 282, no. 16, pp. 1547–1553, 1999.
[7]
M. Fogelholm, “Physical activity, fitness and fatness: relations to mortality, morbidity and disease risk factors. A systematic review,” Obesity Reviews, vol. 11, no. 3, pp. 202–221, 2010.
[8]
J. L. Unick, J. M. Jakicic, and B. H. Marcus, “Contribution of behavior intervention components to 24-month weight loss,” Medicine and Science in Sports and Exercise, vol. 42, no. 4, pp. 745–753, 2010.
[9]
M. L. Klem, R. R. Wing, M. T. McGuire, H. M. Seagle, and J. O. Hill, “A descriptive study of individuals successful at long-term maintenance of substantial weight loss,” American Journal of Clinical Nutrition, vol. 66, no. 2, pp. 239–246, 1997.
[10]
C. A. Pellegrini, S. D. Verba, A. D. Otto, D. L. Helsel, K. K. Davis, and J. M. Jakicic, “The comparison of a technology-based system and an in-person behavioral weight loss intervention,” Obesity, vol. 20, pp. 356–363, 2012.
[11]
D. S. Bond, J. M. Jakicic, S. Vithiananthan et al., “Objective quantification of physical activity in bariatric surgery candidates and normal-weight controls,” Surgery for Obesity and Related Diseases, vol. 6, no. 1, pp. 72–78, 2010.
[12]
D. S. Bond, J. M. Jakicic, J. L. Unick et al., “Pre- to postoperative physical activity changes in bariatric surgery patients: self report vs. objective measures,” Obesity, vol. 18, no. 12, pp. 2395–2397, 2010.
[13]
J. Holtzman, K. Schmitz, G. babes, R. L. Kane, S. Duval, T. J. Wilt, et al., “Effectiveness of behavioral interventions to modify physical activity behaviors in general populations and cancer patients and survivors,” Evidence Report/Technology Assessment 102, Agency for Healthcare Research and Quality, Rockville, Md, USA, 2004.
[14]
K. M. Polzien, J. M. Jakicic, D. F. Tate, and A. D. Otto, “The efficacy of a technology-based system in a short-term behavioral weight loss intervention,” Obesity, vol. 15, no. 4, pp. 825–830, 2007.
[15]
J. E. Donnelly, S. N. Blair, J. M. Jakicic, M. M. Manore, J. W. Rankin, and B. K. Smith, “Appropriate physical activity intervention strategies for weight loss and prevention of weight regain for adults,” Medicine and Science in Sports and Exercise, vol. 41, no. 2, pp. 459–471, 2009.
