Background:A high protein diet combined with exercise is often recommended to promote fat loss and preserve muscle mass during weight loss. This secondary analysis evaluated the associations between dietary protein intake, physical activity, and body weight and composition among individuals engaged in purposeful weight loss attempts. Methods:This study included participants (n = 203) in a three-week ancillary study of the International Weight Control Registry, enrolled between August 2022 and January 2023. Average protein intake (g/kg body weight/d) was estimated from three 24-hour, multi-pass dietary recalls. Body weight, percent body fat (% BF), percent muscle mass (% muscle), and physical activity were monitored using study-provided consumer-grade devices. Multiple linear regression models were used to evaluate associations between protein intake and daily steps and their interaction with body mass index (BMI), % BF, and % muscle. Results:Total protein intake negatively predicted BMI (β [95% CI]=-0.51 [-0.62, -0.39], p < 0.001), % BF (β [95% CI]=-0.37 [-0.49, -0.26], p < 0.001), and positively predicted % muscle (β [95% CI] = 0.26 [0.20, 0.33], p < 0.001). Similarly, average daily steps negatively predicted BMI (β [95% CI]=-0.29 [-0.40, -0.17], p < 0.001), % BF (β [95% CI]=-0.23 [-0.35, -0.12], p < 0.001), and positively predicted % muscle (β [95% CI] = 0.14 [0.08, 0.21], p < 0.001). Total protein intake was significantly associated with BMI across all physical activity levels, with the strongest associations observed at 5,000 steps/day and weakening as the average daily steps increased. Conclusions:Findings broadly support the significance of high protein intake in achieving a lower body weight and a more favorable body composition (i.e., lower % BF and higher % muscle) for individuals previously engaged in weight loss. Additionally, people who are less physically active may require higher protein intake to maintain a lower body weight.

Abstract Background Socioecological factors are associated with key health behaviors that are critical for weight management, and major life events may disrupt engagement in these behaviors. However, the influence of socioecological factors on health behaviors in the midst of major life events is not clear and is difficult to study due to the random and sporadic nature of their occurrence. The COVID‐19 pandemic provided a unique opportunity to study a major life event and its impacts on diet, physical activity, and body weight. Objective This cross‐sectional study aimed to investigate associations between socioecological factors (environmental, interpersonal, and individual) and self‐reported weight change during a major life event using data collected during the COVID‐19 pandemic, and whether the associations were mediated through self‐reported changes in eating and physical activity behaviors. Methods Participants self‐reported socioecological factors, weight change, and changes in eating behaviors (EB) and physical activity (PA) via online questionnaires between December 2020 and October 2021. Changes in EB and PA were measured using scales with higher scores reflecting more positive changes during the COVID‐19 pandemic. Results Participants (n = 1283) were mostly female (84.9%) with age 52.1 ± 14.1 years (mean ± SD) and BMI of 32.9 ± 8.2 kg/m2. Stronger healthy eater and exercise identities (individual factors) were associated with higher EB scores (EBS) and PA scores (PAS), respectively (p's < 0.00001). Less discouragement for healthy eating by family/friends (interpersonal factor) was associated with higher EBS (p = 0.002). Higher EBS and PAS were associated with weight loss. The indirect effect of healthy eater identity (−0.72; 95% CI: −0.90, −0.55) and discouragement for diet (0.07; 95% CI: 0.03, 0.12) on weight change through EBS were significant, as was the indirect effect of exercise identity (−0.25; 95% CI: −0.35, −0.15) on weight change through PAS. Conclusions Stronger identities and less discouragement from family/friends may support health promoting behaviors and weight loss during a major life event, as well as identify additional behavioral targets for lifestyle interventions. Clinical Trial Registration IWCR was registered at ClinicalTrials.gov (NCT04907396).

BACKGROUND:People with physical disabilities (PWD) participate in less physical activity than people without physical disabilities (PWoD), which increases the risk for several negative health consequences. Comparing physical activity between PWD and PWoD remains a challenge since no reliable and valid survey exists to measure physical activity in both populations. The International Physical Activity Questionnaire (IPAQ) was adapted to be inclusive of PWD using a recently developed survey adaption framework; however, the adapted IPAQ has not been assessed for reliability and validity. The objective of this study was to assess the reliability and validity of the adapted IPAQ. METHODS:To assess test-retest reliability, the adapted IPAQ was completed twice within a 72-hour period by 172 individuals (PWD: n = 102, PWoD: n = 70) and compared using intraclass correlation coefficients. Using Spearman rho, convergent validity and construct validity were assessed in 62 individuals by comparing the adapted IPAQ against the original instrument and activity monitor measured step count, respectively. RESULTS:The adapted IPAQ demonstrated moderate test-retest reliability, with intraclass correlation coefficients of total scores for the total sample of .690 (95% confidence interval [CI] .581-.770) and among subgroup analysis (PWD, .640, 95% CI, .457-.761; PWoD, .758, 95% CI, .610-.850). Correlation coefficients were also good for the assessment of convergent validity of total score (.727; 95% CI, .579-.829; P < .001). Construct validity assessment yielded moderate coefficient (.406; 95% CI, .166-.596; P = .001). CONCLUSIONS:The adapted IPAQ demonstrated acceptable reliability and validity and is appropriate for use in PWD and PWoD.

Abstract Background People with physical disabilities (PWD) have an increased risk of obesity and related comorbidities compared with people without physical disabilities (PWoD). Previously identified contributors to weight loss maintenance pose challenges to PWD. However, it is not known if PWD experience less success in weight management. Methods Six hundred and nine participants in the International Weight Control Registry (IWCR) were eligible for this analysis (PWD, n = 174; PWoD, n = 435). Self‐reported weight history metrics were compared using general linear models. Perceived weight history category was compared using Chi‐squared tests. Importance of diet and physical activity strategies for weight management were compared using Wilcoxon rank‐signed tests. Results PWD reported higher current body mass index (BMI) (36.1 ± 0.7 vs. 31.0 ± 0.5; p < 0.0001) and more weight loss attempts (9.1 ± 0.7 vs. 7.1 ± 0.4; p = 0.01) than PWoD. Current weight loss percentage (PWD 13.0 ± 1.0; PWoD, 13.0 ± 0.6; p = 0.97) and weight loss category (χ2 [3, N = 609] = 2.9057, p = 0.41) did not differ between the groups. There were no differences in any weight strategy between PWD who were successful and those who regained. Conclusions PWD and PWoD in the IWCR achieved similar levels of weight maintenance success. However, higher BMI and more weight loss attempts suggest that PWD may face challenges with weight management. More research is needed to identify strategies leading to success for PWD.

Background Personalizing approaches to prevention and treatment of obesity will be a crucial aspect of precision health initiatives. However, in considering individual susceptibility to obesity, much remains to be learned about how to support healthy weight management in different population subgroups, environments and geographical locations. Subjects/methods The International Weight Control Registry (IWCR) has been launched to facilitate a deeper and broader understanding of the spectrum of factors contributing to success and challenges in weight loss and weight loss maintenance in individuals and across population groups. The IWCR registry aims to recruit, enroll and follow a diverse cohort of adults with varying rates of success in weight management. Data collection methods include questionnaires of demographic variables, weight history, and behavioral, cultural, economic, psychological, and environmental domains. A subset of participants will provide objective measures of physical activity, weight, and body composition along with detailed reports of dietary intake. Lastly, participants will be able to provide qualitative information in an unstructured format on additional topics they feel are relevant, and environmental data will be obtained from public sources based on participant zip code. Conclusions The IWCR will be a resource for researchers to inform improvements in interventions for weight loss and weight loss maintenance in different countries, and to examine environmental and policy-level factors that affect weight management in different population groups. This large scale, multi-level approach aims to inform efforts to reduce the prevalence of obesity worldwide and its associated comorbidities and economic impacts. Trial registration NCT04907396 (clinicaltrials.gov) sponsor SB Roberts; Tufts University IRB #13075.