Disability affects the 6-minute walking distance in obese subjects (BMI>40 kg/m(2))

Relationship between Lean Tissue Mass and Muscle Function in Women with Obesity

It is well documented that lean tissue mass (LTM) decreases with aging in patients with obesity, but there is no information available regarding muscle strength changes, a parameter that may be better associated with sarcopenic obesity (SO). The objectives of this study were to analyze the changes in LTM and fat mass (FM), muscle strength and muscle function with aging in women with obesity and to determine the prevalence of SO. LTM and FM were determined by DXA, muscle strength with the hand-grip test and muscle function with the 6 min walk test (6MWT) in 383 women with obesity. A redistribution of the LTM and FM occurred with age, characterized by a gain at the trunk to the detriment of the lower limbs, thus reducting in appendicular LTM indices. The physical performances evaluated by the muscle strength and muscle function decreased concomitantly, and the prevalence of low values for both these parameters was 22.8% and 13.4%, respectively, in the older patients. In summary, although a reduction in appendicular LTM and muscle performances occurred with age and resulted in an increase in the prevalence of SO, the number of women with obesity affected by SO remained low (n ≤ 15), even in those older than 60 years.

[Six minute walk test: From normal to morbid obesity subject]

Introduction

Morbid obesity is associated with alterations in the ability to walk, however, the behavior of the 6-minute walk test in subjects with increases in body mass index is unknown.

Objective

To describe the behavior of the 6-minute walk test in subjects with normal body mass index to morbid obesity.

Methods

Through an analytical cross-sectional design, subjects of both genders from 18 to 60 years old with body mass index were studied: Normal (BMI:18.5-24.9); overweight (BMI:25-29.9); obesity (BMI:30-39.9); morbid obesity (BMI:>40) kg/m2. A 6-minute walk test was performed, demographic variables and pathological personal history were delimited. BMI categories were analyzed with one-way ANOVA and Bonferroni adjustment, and gender with t-test, both for independent groups, and Pearson's correlations for the various variables.

Results

480 subjects of both genders were studied in four groups. Age: men 43 ± 11 and women 45 ± 10 years old. Percentage diabetes mellitus (6.7%), arterial hypertension (18.3%). Meters walked men vs. women by body mass index (normal: 483 ± 56 vs. 449 ± 61; overweight: 471 ± 55 vs. 441 ± 44; obesity: 455 ± 70 vs. 421 ± 47; morbid obesity: 443 ± 49 vs. 403 ± 54, p < 0.05). Correlation body mass index-meters walked: r: -0.446 (p < 0.0001).

Conclusions

Meters walked in the 6-minute walk test decreased as body mass index increased. The male gender walked more meters in all categories.

Obesity, Preserved Ejection Fraction Heart Failure, and Left Ventricular Remodeling

Owing to the overwhelming obesity epidemic, preserved ejection fraction heart failure commonly ensues in patients with severe obesity and the obese phenotype of preserved ejection fraction heart failure is now commonplace in clinical practice. Severe obesity and preserved ejection fraction heart failure share congruent cardiovascular, immune, and renal derangements that make it difficult to ascertain whether the obese phenotype of preserved ejection fraction heart failure is the convergence of two highly prevalent conditions or severe obesity enables the development and progression of the syndrome of preserved ejection fraction heart failure. Nevertheless, the obese phenotype of preserved ejection fraction heart failure provides a unique opportunity to assess whether sustained and sizeable loss of excess body weight via metabolic bariatric surgery reverses the concentric left ventricular remodeling that patients with preserved ejection fraction heart failure commonly display.

Predicting recovery and disability after surgery in patients with severe obesity: The role of the six-minute walk test

The most appropriate method to predict postoperative outcomes in patients with severe obesity undergoing elective non-bariatric surgery is not known. We conducted a single-centre prospective cohort study in patients with a body mass index of at least 35 kg/m² undergoing non-bariatric, non-cardiac surgery. Patients completed the six-minute walk test prior to surgery. Disability was measured before and six months after surgery using the World Health Organization disability assessment schedule. Primary outcome measures included quality of recovery at one month and significantly increased disability at six months after surgery. A total of 293 patients participated. The median body mass index was 41 kg/m². Patients generally recovered well. Following surgery, 9% of patients experienced a poor quality of recovery and 7% developed a significant increase in disability. The proportion of patients free from clinically significant disability increased from 66% prior to surgery to 90% at six months after surgery. The distance walked in six minutes was weakly predictive of poor recovery at one month and significantly increased disability at six months; weight and body mass index were not. The area under the receiver operating characteristic curve was 0.65 (95% confidence intervals 0.51 to 0.78) for poor recovery and 0.64 (95% confidence intervals 0.51 to 0.77) for increased disability. A preoperative six-minute walk test distance of 308 m was the best cut-off value for predicting increased postoperative disability (sensitivity 0.68, specificity 0.63). The six-minute walk test was most discriminatory at shorter distances. This population of patients with severe obesity appeared to recover well and had few adverse outcomes. The degree of functional capacity was more important than the degree of obesity in predicting postoperative outcomes.

Association Between Body Mass Index and Disability in Children With Charcot-Marie-Tooth Disease

BACKGROUND AND OBJECTIVES

This study examined the association between body mass index (BMI) and disability in children with Charcot-Marie-Tooth disease (CMT).

METHODS

We conducted a cross-sectional analysis of 477 patients with CMT who were 3 to 20 years of age from the Inherited Neuropathy Consortium and 316 age- and sex-matched healthy children from the 1,000 Norms Project. BMI was categorized according to the International Obesity Task Force (IOTF) criteria, and BMI categorization was compared with healthy children. IOTF categories (adult equivalent BMI cut points) were severely underweight (BMI <17 kg/m2), underweight (BMI ≥17-<18.5 kg/m2), healthy weight (BMI ≥18.5-<25 kg/m2), overweight (BMI ≥25-<30 kg/m2), and obese (BMI ≥30 kg/m2). Scores on the 0 to 44-point CMT Pediatric Scale (CMTPedS), a well-validated measure of disability, were examined in relation to BMI.

RESULTS

There was a higher proportion of children with CMT categorized as severely underweight (5.7% vs 0.3%), underweight (10.3% vs 5.1%), and obese (7.3% vs 3.8%) (p < 0.05). Fewer children with CMT were categorized as healthy weight (61.8% vs 74.4%) (p < 0.05), and the proportion of overweight (14.9% vs 16.5%) between groups was similar. CMTPedS scores (mean ± SD) for weight categories were as follows: severely underweight 27 ± 9, underweight 20 ± 8, healthy weight 17 ± 9, overweight 17 ± 9, and obese 22 ± 10. Compared to children with a healthy weight with CMT, being severely underweight was associated with being more disabled (p < 0.001), as was being obese (p = 0.015).

DISCUSSION

The proportion of children with CMT who are underweight or obese is higher compared to age- and sex-matched healthy children. In children with CMT, being underweight or obese is associated with greater disability, when compared to children with CMT of healthy weight.

The effects of core stabilization exercise program in obese people awaiting bariatric surgery: A randomized controlled study

OBJECTIVE

The aim of this study was the effects of the core stabilization exercise program (CSEP) and physical activity counseling on functional capacity, physical fitness, physical activity, fatigue and quality of life (QoL) in obese people awaiting bariatric surgery.

METHODS

Twenty-one patients were divided into two groups: an exercise group (n = 10) and a control group (n = 11). Both groups received physical activity counseling, but the exercise group also performed an 8-week CSEP. Functional capacity, physical fitness, physical activity, fatigue and QoL were assessed at baseline and after 8 weeks.

RESULTS

After eight weeks, results showed significant improvements in all parameters except for body composition for the exercise group, comparing to the control group (effect size = 0.40-0.87, p < 0.05).

CONCLUSIONS

Implementing an 8-week adding CSEP to physical activity counseling provided significant improvements in functional capacity, physical fitness, physical activity, fatigue and QoL compared to physical activity counseling in obese people awaiting bariatric surgery.

Reference Value for the Distance Walked in the Six-Minute Walk Test in Obese Brazilian Men in the Preoperative Period of Bariatric Surgery

BACKGROUND

Obesity has several effects on the mechanics of the rib cage that may impair the exercise performance of obese individuals and therefore impact the assessment of surgical risk. This study aimed to establish a reference value for the 6-minute walk distance (6 MWD) in obese Brazilian men in the preoperative period of bariatric surgery that considers the effect of lung function.

METHODS

This was a cross-sectional study in which 104 obese men underwent the six-minute walk test (6 MWT) before bariatric surgery. They also underwent the spirometry test and respiratory muscle strength measurement before the 6 MWT.

RESULTS

The 6 MWD was correlated with age (r = -0.388, p=0.0005), weight (r = -0.365, p=0.0007), height (r = 0.285, p=0.022), body mass index (BMI) (r = -0.543, p < 0.0001), forced vital capacity (FVC) (r = 0.472, p < 0.0001), peak expiratory flow (r = 0.253, p=0.031), and maximal inspiratory pressure (r = 0.313, p=0.017). In the stepwise forward regression analysis, BMI, FVC, and age were the only variables that independently predicted the 6 MWD and explained 40% of its variability. The reference equation proposed for obese Brazilian men is 6 MWD (m) = 570.5 - (3.984 × BMI_kg/m2) + (1.093 × FVC_%predicted) - (0.836 × age_yrs).

CONCLUSION

In this sample of obese Brazilian men, lung function contributed to poor performance in the 6 MWT. In these individuals, BMI, FVC, and age were the variables that composed the reference equation for the 6 MWD. Thus, in several clinical settings, such as in the evaluation before bariatric surgery, pulmonary function data are important to determine the reference value for the 6 MWD.

Demographic/anthropometric factors and physiological performance-related parameters associated with the six-minute walk test in bariatric surgery candidates, from Valdivia, Chile

ABSTRACT The six-minute walk test (6MWT) is widely used to measure functional capacity in special populations. However, the factors associated with its performance in candidates for bariatric surgery are unclear. Therefore, this study aimed to investigate the influence of anthropometric and physiological factors in the 6MWT performance in bariatric surgery candidates. This cross-sectional study included 107 candidates for bariatric surgery. Anthropometric factors considered: gender, weight, height, body mass index (BMI), waist-to-hip, and waist-to-height ratios. Along with distance covered during 6MWT, physiological factors such as ratings of perceived exertion (RPE) and heart rate reserve percentage used (%HRR) were recorded. Among the 107 patients (mean age: 39.6 years), 83 volunteers were accepted to perform the 6MWT. No gender differences were observed in terms of distance covered, %HRR, and RPE during the 6MWT. Moreover, BMI and %HRR explained 21% of the 6MWT distance covered. Furthermore, participants with BMI ≤41.5 kg/m2 walked ~50 meters more than their peers above this level (p=0.05). Interestingly, heart rate increase during the 6MWT was lower than described for healthy populations. BMI and %HRR partially explain the variability of the 6MWT performance in bariatric surgery candidates.

Contribution of lung function in predicting distance covered in the 6-min walk test in obese Brazilian women

Obesity affects the respiratory system through various mechanisms, including systemic inflammation and direct mechanical hindrance due to fat deposition in the chest and abdomen. In addition, changes in the neural control of respiration and increases in thoracic blood volume can promote abnormalities in lung function. Thus, determining relationships between the distance covered in the 6-min walk test (6MWT) and demographic and lung function variables may help us better understand the mechanisms involved in reduced functional exercise capacity in obesity. To explore the determinants of the 6-min walking distance (6MWD) and evaluate the influence of lung function on the distance covered, 263 obese Brazilian women performed the 6MWT and underwent spirometry and respiratory muscle strength measurement. The mean age was 41.8±11.1 years. The mean body mass index (BMI) was 45±8 kg/m². The 6MWD showed correlations with height (r=0.319), age (r=-0.281), weight (r=-0.370), BMI (r=-0.561), forced vital capacity (FVC, r=0.443), expiratory peak flow (r=0.278), maximal inspiratory pressure (MIP, r=0.326), and maximal expiratory pressure (r=0.259), all with P<0.0001. In the stepwise forward regression analysis, BMI, FVC, age, and MIP were the independent predictive variables for 6MWD, explaining 41% of its variability. The reference equation including lung function was as follows: 6MWD (m) = 513.6 - (4.439 × BMI_kg/m2) + (1.136 × FVC_%predicted) - (1.048 × age_yrs) + (0.544 × MIP_%predicted). Thus, the inclusion of lung function in a reference equation for 6MWD contributes to a better prediction of the distance covered in this population.

Weight-based reference equations for the 6-min walk test can be misleading in obese patients

A 79-year-old female presented to a hospital-based laboratory for pulmonary function testing and a 6-min walk test (6MWT). The patient's chief complaint was dyspnoea on exertion. The patient was a life-long nonsmoker with a history of interstitial lung disease and morbid obesity (body mass index (BMI) 44.9 kg·m⁻²). The patient's baseline spirometry data were within normal limits but the diffusing capacity was moderately reduced (50% of predicted; z-score −4.05) [1, 2].

Weight-based reference equations for the 6-min walk test can produce normal results despite poor performance. Using ideal body weight- or non-weight-based reference equations for the 6-min walk test may produce more clinically meaningful results.https://bit.ly/2wE9Sdn

Impact of Disability, Psychological Status, and Comorbidity on Health-Related Quality of Life Perceived by Subjects with Obesity

Obesity is a rapidly growing public health problem affecting an increasing number of countries worldwide and creating substantial financial and health burdens. Obesity has a negative impact on health-related quality of life (HRQoL) with reference to physical and mental health status, social relationships, and economic factors. The aim of the present study is to investigate the association of number of comorbidities, psychological status, and disability level with HRQoL in a sample of subjects with obesity.

METHODS

A total of 273 subjects with obesity (199 women and 74 men) were recruited. Medical history and anthropometric measurements were carried out. The Italian version of the Laval questionnaire, the TSD-OC (SIO test for obesity-related disabilities), and SCL-90 (Symptom Checklist-90) tests were administered. The association between HRQoL (global and different domains scores of the Laval questionnaire - dependent variable) and age, body mass index (BMI), comorbidity, TSD-OC, and SCL-90 was analysed using a stepwise linear regression model.

RESULTS

BMI, disability (TSD-OC global score), and psychological symptoms (SCL-90 global severity index) were found to be the main determinants of HRQoL. Single domains of HRQoL (symptoms, activity/mobility, personal hygiene/clothing, emotions, social interaction, and sexual life) showed different patterns of associations with each domain of the Laval questionnaire. BMI, pain, and social life disruptions were found to be significantly associated with most of the HRQoL domains while age, comorbidities, psychological problems (depression, interpersonal symptoms, somatization), and disability were associated with only some domains of the Laval questionnaire. Education, psychological symptoms (obsessive-compulsive, anxiety, hostility, phobic anxiety, paranoid ideation), and disability domains (stiffness, housework, outdoor activities, occupational activities) were not associated with any of the dimensions of the Laval questionnaire.

DISCUSSION/CONCLUSION

The present study identified key determinants of QoL in subjects with obesity, which could help in refining the multidimensional diagnostic assessment of obesity as well as designing more effective interventions to improve HRQoL in these patients.

Physical capacity outcomes in patients with severe obesity after 12 months of physician-led multidisciplinary team care: A case series from a public hospital clinical obesity service

Impaired physical capacity is common in people with severe levels of obesity. We aimed to investigate changes in physical capacity outcomes in patients with severe obesity following 12 months of physician-led multidisciplinary care from a "real world" Australian public hospital setting using a case series study design. We extracted data from medical records for all of the eligible patients referred to our clinical obesity service from 2010 to 2015 (69 of 239). We found significant (P < .05) pre-test/post-test (mean ± SD) improvements in the 6-minute walk test (6MWT) (339 ± 120 to 417 ± 112 m); 30-second sit-to-stand test (11 ± 4 to 15 ± 6 counts) and sit-and-reach test (-12 ± 13 to -8 ± 15 cm). Using linear mixed-effects models adjusting for repeated measurements over time (baseline vs 12 months) and testing for potential predictors, we found: mean 6MWT was associated with 12-month time period (56 m), body mass index (BMI, -3 m), no walking aid over 12 months (106 m) and no opioid analgesics (75 m); mean sit-to-stand was associated with 12-month time period (3 counts), age at referral (-0.2 counts), BMI (-0.2 counts), and diabetes (3 counts); and mean sit-and-reach was associated with 12-month time period (5 cm), female gender (5 cm) and total medications (-0.9 cm). Using causal mediation analysis, our results show that total exercise classes partially mediates change in walking capacity among those with cardiovascular disease. Our study shows that significant and clinically important improvements in physical capacity outcomes in patients with severe obesity can be achieved following 12 months of intensive specialist obesity services, such as ours.

The clinical, functional and disability characteristics of patients with severe obesity presenting for non-bariatric surgery

The clinical and functional characteristics of patients with severe obesity who present for non-bariatric surgery have rarely been described. For this study, 293 such patients (mean body mass index 42 kg/m2) were investigated using their medical records, a 6-minute walk test, N-terminal pro B-type natriuretic peptide measurement, and the World Health Organization Disability Assessment Schedule 2.0 measure of disability. Cardiorespiratory disease and diabetes were common, with blood tests revealing a high probability of additional unexpected and undiagnosed renal and cardiac disease in a significant proportion of patients. One-third of patients had natriuretic peptide values that identify early left ventricular dysfunction in the community, with 16% above a value described as useful in predicting adverse outcomes for elective surgical patients. Only 10% of patients walked a distance within 10% of that predicted in six minutes, and 22% did not complete the test. Over one-third of patients (34%) had a clinically significant level of disability, with those unable to walk for six minutes describing higher levels of disability. Functional capacity as measured by the 6-minute walk test was significantly lower than would be expected from age, gender, and weight alone, and was related to age and degree of disability but not body mass index. We describe a severely obese population presenting for non-bariatric surgery who had significant levels of comorbid disease, functional impairment, and disability that were not apparent on routine preoperative assessment.

Improvement in 6-min Walk Test Distance Following Treatment for Behavioral Weight Loss and Disinhibited Eating: an Exploratory Secondary Analysis

BACKGROUND

Poor functional exercise capacity is common among those with obesity; however, objective measures of exercise capacity are rarely examined in behavioral treatments targeting obese individuals. We examined whether a 4-week acceptance and commitment therapy (ACT) intervention for disinhibited eating or a behavioral weight loss (BWL) intervention improved exercise capacity and explored demographic and disinhibited eating variables related to exercise capacity.

METHODS

Veterans (n = 61), randomized to receive ACT or BWL, completed an assessment of exercise capacity via the 6-min walk test (6MWT) at baseline and 6-month follow-up. Measures of disinhibited eating patterns and body mass index (BMI), at baseline and post-treatment, were also collected. Change in 6MWT distance and treatment group differences were examined using mixed ANOVAs. Characteristics related to baseline 6MWT and predictors of improvement in 6MWT at 6 months were examined with hierarchical multiple regression.

RESULTS

There were overall significant improvements on the 6MWT from baseline to 6-month follow-up (F(1,59) = 11.14, p = .001, η_p² = .159) but no differences between the ACT and BWL groups. Baseline BMI (β = - .33, p = .005) was the only variable related to baseline 6MWT. Improvements on the 6MWT were related to younger age (β = - .41, p = 0.001), female gender (β = .36, p = .001), and treatment-related increases in dietary restraint behaviors (β = .42, p = .001).

CONCLUSIONS

Functional exercise capacity improved among participants completing behavioral interventions for weight and disinhibited eating. Improvements in dietary behavior regulatory skills may have generalized to improved regulation in other behavioral domains associated with exercise capacity.

Handgrip strength measurement in patients with chronic obstructive pulmonary disease: Possible predictor of exercise capacity

BACKGROUND

Impaired exercise capacity is one of the most important prognostic factors for patients with chronic obstructive pulmonary disease (COPD). The 6-min walk test (6MWT) is a widely used method for assessing exercise capacity in patients with COPD. However, the 6MWT requires considerable effort from patients. Therefore, a less physically demanding, but also noninvasive, method is warranted. The objective of this study was to determine the predictors of the 6MWT distance (6MWD) in patients with COPD.

METHODS

This retrospective observational study enrolled 133 Japanese patients with COPD. All patients underwent the 6MWT, COPD assessment test (CAT), spirometry, respiratory muscle strength evaluation, body composition assessment, and handgrip strength (HGS) measurement. We examined the associations between the 6MWD and evaluated parameters.

RESULTS

From single regression analysis, the 6MWD was significantly correlated with age, CAT score, several spirometric measurements (e.g., percentages of forced vital capacity, forced expiratory volume in 1 s, and carbon monoxide diffusing capacity of the lungs [%DLCO]), respiratory muscle strength parameters (e.g., percentages of maximal expiratory and inspiratory pressures), skeletal muscle mass index, and HGS. In multiple regression analysis, age, CAT score, %DLCO, and HGS were independent predictors of the 6MWD. The %DLCO and HGS were strongly correlated as predictors of the 6MWD (p < 0.001).

CONCLUSIONS

We found that HGS was significantly correlated with the 6MWD compared with spirometric measurements or respiratory muscle strength parameters in Japanese patients with COPD, suggesting that HGS could be a simple and noninvasive predictor of the 6MWD in patients with COPD.

Association between body mass index and functional fitness of 9- to 10-year-old Chilean children

OBJECTIVE

This study aimed to determine the association between body mass index (BMI) and functional fitness (FF) in 9- to 10-year-old Chilean children.

METHODS

This was an analytical and cross-sectional study with a probabilistic sample consisting of 139 children of both sexes. Anthropometric measurements, hemodynamic variables, physical activity (PAQ-C), and FF (measured by a 6-minute walk test: 6MWT) were recorded. If the distance walked was <10th percentile, FF was considered low. Means of variables between each group were compared by Student's t test, and Pearson's test was used to determine correlations between variables. Multivariable analyses were performed to identify factors associated with FF with a level of significance P < .05. All these analyses were performed with the STATA 15.0 program.

RESULTS

It was clear boys walked a greater distance than girls (P = .006); overweight subjects had lower physical performance than normal-weight subjects (P = .035). There was a significant correlation between weight (r = -0.511), height (r = 0.502), BMI (r = -0.352), waist circumference (r = -0.310), neck circumference (r = -0.204), and percentage fat mass (r = -0.310) for distance walked. Overweight (OR 2.06; 95% CI 1.6-4.8), high percentage fat mass (OR 1.84; 95% CI 1.2-3.2), and abdominal obesity (OR 1.15; 95% CI 1.1-1.7) were associated with significantly higher odds of low FF.

CONCLUSION

Lower performance was exhibited in Chilean children for the 6MWT. Overweight, fat mass, and abdominal obesity were associated with lower FF. This study contributes empirical information to construct normality curves for the Chilean child population.

Physical performance measures in screening for reduced lean body mass in adult females with obesity

BACKGROUND & AIMS

Little is known about the reduction of lean body mass (LBM) in obesity, or how to identify it in standard clinical settings. We therefore aimed to assess the prevalence of low LBM in adult females with obesity, and to identify the reliability of simple tools for its screening in this population.

METHODS AND RESULTS

Dual-energy X-ray absorptiometry (DXA) body composition assessment was used to categorise 147 female participants with obesity as with or without low LBM, according to the new definition that takes into account both appendicular lean mass (ALM) and body mass index (BMI)-ALM/BMI <0.512. Participants were also administered the six-minute walking test, handgrip-strength test and 4-metre gait-speed test. Of the sample of 147 participants, 93 (63.3%) met the criteria for reduced LBM. Stepwise multivariate logistic regression analysis showed that the six-minute walking test was the only independent test associated with low LBM (OR = 0.992, 95%CI 0.987-0.998). Receiver operating characteristic (ROC) curve analysis found that the discriminating cut-off points of the tests considered were 470 m, 3.30 s (gait speed = 1.2 m/sec) and 23.5 kg respectively; the 4-metre gait-speed test seems to provide the best balance of sensitivity and specificity, and the greatest discriminatory power at 90% sensitivity.

CONCLUSIONS

Treatment-seeking adult females with obesity display a great prevalence of reduced LBM. The six-minute walking test was the only independent test associated with low LBM, but the 4-metre gait-speed test seems to be the most accurate functional test for screening for this condition in that population.

Effects of body weight loss program on parameters of muscle performance in female obese adults

BACKGROUND

Body weight loss program may lead to a decrease in lean body mass affecting negatively muscle performance in obese subjects. Thus, the aim of this study was to examine the effect of weight loss on muscle performance in female obese subjects.

METHODS

Eighty obese female adults were enrolled for a 2-month unsupervised aerobic training (UAT) plus nutritional program. In the pre- and postintervention body composition was evaluated by hand-to-foot bioelectrical impedance method, body strength using handgrip test, and lower muscle power was assessed by a 5-repetition chair stand test (CST) and 30-s chair stand test (30sCST) wearing a dynamometer.

RESULTS

Thirty-six subjects completed the protocol, 39% had high compliance (HC), while 61% had low compliance (LC) to exercise prescription. HC group showed a significant decreased body weight, percent of fat mass and lean muscle mass after training. Both groups significantly increased CST performance while only HC significantly increased 30sCST. No differences were found in CST muscle power in both groups between pre- and post-training. However, evaluation of muscle power during 30sCST showed significantly higher value in HC group than LC group after training.

CONCLUSIONS

The results of our study show that although total lean muscle mass decreased after UAT, lower body muscle efficiency increased while muscle power did not change suggesting that in obese patients UAT can help to optimize weight loss and body efficiency. The data might be helpful for exercise professionals to evaluate correctly the muscle performance in obese adults after weight loss programs.

Exercise Testing Reveals Everyday Physical Challenges of Bariatric Surgery Candidates

BACKGROUND

Few studies have quantified cardiorespiratory fitness among individuals seeking bariatric surgery. Treadmill testing allows researchers to determine exercise capacity through metabolic equivalents. These findings can assist clinicians in understanding patients' capabilities to carry out various activities of daily living. The purpose of this study was to determine exercise tolerance and the variables associated with fitness, among individuals seeking bariatric surgery.

METHODS

Bariatric surgery candidates completed submaximal treadmill testing and provided ratings of perceived exertion. Each participant also completed questionnaires related to history of exercise, mood, and perceived barriers/benefits of exercise.

RESULTS

Over half of participants reported that exercise was "hard to very hard" before reaching 70% of heart rate reserve, and one-third of participants reported that exercise was "moderately hard" at less than 3 metabolic equivalents (light activity). Body mass index and age accounted for the majority of the variance in exercise tolerance, but athletic history, employment status, and perceived health benefits also contributed. Perceived benefit scores were higher than barrier scores.

CONCLUSION

Categories commonly used to describe moderate-intensity exercise (3-6 metabolic equivalents) do not coincide with perceptions of intensity among many bariatric surgery candidates, especially those with a body mass index of 50 or more.

Obesity, Physical Fitness and Inflammation in the Elderly

Among the elderly, obesity is paradoxically associated with a lower mortality risk. Thus, this study describes fitness levels by Body Mass Index (BMI) category and the associations of high-sensitivity C-reactive protein (hs-CRP) and Vitamin D levels with muscle strength, in community-dwelling older adults. A cross-sectional study, with 1338 subjects having mean age of 78.3 years, were assessed in anthropometrics, muscle strength, and cardiorespiratory fitness. In a sub-sample, blood samples were collected and objective markers of inflammation were provided: high-sensitivity C-reactive protein (hs-CRP) and Vitamin D (25(OH) D). Obese women (BMI ≥ 30.0 kg/m²) showed significantly better results for grip strength than normal weight group (BMI between 18.5–24.9 kg/m²): 22.3 (7.0) vs. 20.0 (6.8); p = 0.002. After adjustment, higher levels of hs-CRP were an independent predictor of lower levels of grip strength (β = −0.213, 95% CI: −0.424; −0.002) and Vitamin D levels were positively associated with higher levels of muscle strength (β = 0.098, 95% CI: 0.008–0.189). The multivariate analysis found a significant and positive association between 25(OH) D and grip strength: (β = 0.098, 95% CI: 0.008–0.189). A positive pattern of higher levels of absolute strength among obese older subjects could have an important impact on morbidity and mortality risk, through the inverse association with acute inflammation and an increase in Vitamin D profile.

Comparison of exercise capacity in COPD and other etiologies of chronic respiratory failure requiring non-invasive mechanical ventilation at home: retrospective analysis of 1-year follow-up

INTRODUCTION

The objective of this study was to compare the change in 6-minute walking distance (6MWD) in 1 year as an indicator of exercise capacity among patients undergoing home non-invasive mechanical ventilation (NIMV) due to chronic hypercapnic respiratory failure (CHRF) caused by different etiologies.

METHODS

This retrospective cohort study was conducted in a tertiary pulmonary disease hospital in patients who had completed 1-year follow-up under home NIMV because of CHRF with different etiologies (ie, chronic obstructive pulmonary disease [COPD], obesity hypoventilation syndrome [OHS], kyphoscoliosis [KS], and diffuse parenchymal lung disease [DPLD]), between January 2011 and January 2012. The results of arterial blood gas (ABG) analyses and spirometry, and 6MWD measurements with 12-month interval were recorded from the patient files, in addition to demographics, comorbidities, and body mass indices. The groups were compared in terms of 6MWD via analysis of variance (ANOVA) and multiple linear regression (MLR) analysis (independent variables: analysis age, sex, baseline 6MWD, baseline forced expiratory volume in 1 second, and baseline partial carbon dioxide pressure, in reference to COPD group).

RESULTS

A total of 105 patients with a mean age (± standard deviation) of 61±12 years of whom 37 had COPD, 34 had OHS, 20 had KS, and 14 had DPLD were included in statistical analysis. There were no significant differences between groups in the baseline and delta values of ABG and spirometry findings. Both univariate ANOVA and MLR showed that the OHS group had the lowest baseline 6MWD and the highest decrease in 1 year (linear regression coefficient -24.48; 95% CI -48.74 to -0.21, P=0.048); while the KS group had the best baseline values and the biggest improvement under home NIMV (linear regression coefficient 26.94; 95% CI -3.79 to 57.66, P=0.085).

CONCLUSION

The 6MWD measurements revealed improvement in exercise capacity test in CHRF patients receiving home NIMV treatment on long-term depends on etiological diagnoses.

Accuracy and Usability of a Self-Administered 6-Minute Walk Test Smartphone Application

BACKGROUND

The 6-minute walk test (6MWT) independently predicts congestive heart failure severity, death, and heart failure hospitalizations, but must be administered in clinic by qualified staff on a premeasured course. As part of the Health eHeart Study, we sought to develop and validate a self-administered 6MWT mobile application (SA-6MWTapp) for independent use at home by patients.

METHODS AND RESULTS

We performed a validation study of an SA-6MWTapp in 103 participants. In phase 1 (n=52), we developed a distance-estimation algorithm for the SA-6MWTapp by comparing step counts from an Actigraph and measured distance on a premeasured 6MWT course with step counts and estimated distance obtained simultaneously from our SA-6MWTapp (best estimation algorithm, r=0.89 [95% confidence interval 0.78-0.99]). In phase 2, 32 participants (including those with congestive heart failure and pulmonary hypertension) used the SA-6MWTapp independently in clinic, and the distance estimated by the SA-6MWTapp was compared with the measured distance (r=0.83 [95% confidence interval 0.79-0.92]). In phase 3, 19 patients with congestive heart failure and pulmonary hypertension consecutively enrolled from clinic performed 3.2±1 SA-6MWTapp tests per week at home over 2 weeks. Distances estimated from the SA-6MWTapp during home 6MWTs were highly repeatable (coefficient of variation =4.6%) and correlated with in-clinic-measured distance (r=0.88 [95% confidence interval 0.87-0.89]). Usability surveys performed during the second (in-clinic) and third (at-home) phases demonstrated that the SA-6MWTapp was simple and easy to use independently.

CONCLUSIONS

An SA-6MWTapp is easy to use and yields accurate repeatable measurements in the clinic and at home.

Correlation between Body Composition and Walking Capacity in Severe Obesity

Background

Obesity is associated with mobility reduction due to mechanical factors and excessive body fat. The six-minute walk test (6MWT) has been used to assess functional capacity in severe obesity.

Objective

To determine the association of BMI, total and segmental body composition with distance walked (6MWD) during the six-minute walk test (6MWT) according to gender and obesity grade.

Setting

University of São Paulo Medical School, Brazil; Public Practice.

Methods

Functional capacity was assessed by 6MWD and body composition (%) by bioelectrical impedance analysis in 90 patients.

Results

The mean 6MWD was 514.9 ± 50.3 m for both genders. The male group (M: 545.2 ± 46.9 m) showed a 6MWD higher (p = 0.002) than the female group (F: 505.6 ± 47.9 m). The morbid obese group (MO: 524.7 ± 44.0 m) also showed a 6MWD higher (p = 0.014) than the super obese group (SO: 494.2 ± 57.0 m). There was a positive relationship between 6MWD and fat free mass (FFM), FFM of upper limps (FFM_UL), trunk (FFM_TR) and lower limbs (FFM_LL). Female group presented a positive relationship between 6MWD and FFM, FFM_UL and FFM_LL and male group presented a positive relationship between 6MWD and FFM_TR. In morbid obese group there was a positive relationship between 6MWD with FFM, FFM_UL, FFM_TR and FFM_LL. The super obese group presented a positive relationship between 6MWD with FFM, FFM_TR and FFM_LL.

Conclusions

Total and segmental FFM is associated with a better walking capacity than BMI.

Treatment of body composition changes in obese and overweight older adults: insight into the phenotype of sarcopenic obesity

In recent years, mounting interest has been directed to sarcopenic obesity (SO), given the parallel increase of life expectancy and prevalence of obesity in Western countries. The phenotype of SO is characterized by the coexistence of excess fat mass and decreased muscle mass, leading to the impairment of physical performance. The aim of the present review was to summarize the impact of different treatment strategies contrasting body composition changes in older obese and overweight subjects, providing insight into the SO phenotype. Revision questions were formulated; relevant articles were identified from Pubmed through a systematic search strategy: definition of the search terms (sarcopenic obesity, diet, nutritional supplements, physical activity, exercise, pharmacological treatment); limits: papers published in the last 10 years; humans; age ≥ 60 years old; body mass index >25 kg/m(2); language: English. Studies dealing with sarcopenia associated to cancer cachexia or neurological diseases, any malignant disease, inflammatory or autoimmune diseases, corticosteroids for systemic use, bedridden subjects, and syndromic obesity were excluded. 14 articles were identified for inclusion in the present systematic review, and were grouped basing on the type of the main intervention: data assessing body composition changes after combined lifestyle interventions, exercise/physical activity, dietary interventions, and pharmacological treatment. Most of the studies were randomized, controlled. Sample size ranged from 12 to 439 subjects, and study duration varied from 6 weeks to 12 months. Weight loss based on diet combined with exercise seems to be the best strategy to adopt for treatment of phenotypic aspects of SO, improving metabolic consequences related to excess fat, preserving lean mass, and allowing functional recovery.

The functional exercise capacity and its correlates in obese treatment-seeking people with binge eating disorder: an exploratory study

PURPOSE

The primary aim was to compare the functional exercise capacity between obese treatment-seeking people with and without binge eating disorder (BED) and non-obese controls. The secondary aim was to identify clinical variables including eating and physical activity behaviour, physical complaints, psychopathology and physical self-perception variables in obese people with BED that could explain the variability in functional exercise capacity.

METHODS

Forty people with BED were compared with 20 age-, gender- and body mass index (BMI)-matched obese persons without BED and 40 age and gender matched non-obese volunteers. A 6-minute walk test (6MWT), the Baecke physical activity questionnaire, the Symptom Checklist-90, the Physical Self-Perception Profile and the Eating Disorder Inventory were administered. Physical complaints before and after the 6MWT were also documented.

RESULTS

The distance achieved on the 6MWT was significantly lower in obese participants with BED (512.1 ± 75.8 m versus 682.7 ± 98.4, p < 0.05) compared to non-obese controls. No significant differences were found between obese participants with and without BED. Participants with BED reported significantly (p < 0.05) more musculoskeletal pain and fatigue after the walk test than obese and non-obese controls. A forward stepwise regression analysis demonstrated that sports participation and perceived physical strength explained 41.7% of the variance on the 6MWT in obese participants with BED.

CONCLUSION

Physical activity participation, physical self-perception and perceived physical discomfort during walking should be considered when developing rehabilitation programs for obese people with BED.

IMPLICATIONS FOR REHABILITATION

Rehabilitation programmes in people with binge eating disorder should incorporate a functional exercise capacity assessment. Clinicians involved in the rehabilitation of people with binge eating disorder should consider depression and lower self-esteem as potential barriers. Clinicians should take into account the frequently observed physical discomfort when developing rehabilitation programmes for people with binge eating disorder.

Obesity treatment: results after 4 years of a Nutritional and Psycho-Physical Rehabilitation Program in an outpatient setting

INTRODUCTION

Obesity is a chronic disease as well as a risk factor for cardiovascular, metabolic and osteoarticular diseases, affecting the psychosocial health and the quality of life. Recent evidence suggests that the adequate treatment of obesity should provide a multidimensional multidisciplinary approach including nutritional therapy, psycho-educational classes and physical reconditioning/motor rehabilitation. The aim of this approach should be to maintain the results over time with a positive impact on the obesity-related cardiovascular and metabolic risk.

AIM OF THE STUDY

To evaluate the effectiveness of a multidisciplinary Nutritional and Psycho-Physical Reconditioning Program (NPPRP) in an outpatient setting.

MATERIALS AND METHODS

The observational prospective cohort study involved subjects, aged from 18 to 65 years, with a BMI >30 kg/m(2), who were followed up over 48 months. After the first nutritional and psychological examination, patients who refused NPPRP were treated according to standard nutrition procedures (SNT). Patients were followed through monthly medical examinations and then by annual telephonic structured interviews for 4 years. Changes in body weight, eating behavior, physical activity performance, and the occurrence of clinical obesity-related complications were considered as outcome measures.

RESULTS

Of 464 enrolled patients, 161 (34.7%) took part in the follow-up. From the enrollment to the end of follow-up, weight loss was greater in the NPPRP group than in the SNP group (-8.08 ± 10 kg versus -3.0 ± 6 kg). After 4 years eating behavior improved in both groups. The percentage of patients who continued to perform physical activity was higher in the NPPRP group than in the SNT group (61.0 versus 34.1%). The SNT group reported complications more frequently than the NPPRP group: hypertension (19 versus 5.8%), dyslipidemia (19.4 versus 12.7%), and skeletal problems (26.9 versus 17.5%). The main reasons for drop-out from the rehabilitation program were logistic problems (distance or time) in both groups; disappointment was higher in the SNT group than in the NPPRP group (37.8 versus 15.6%).

CONCLUSION

A multidimensional multidisciplinary approach including nutritional intervention and psycho-physical rehabilitation, set against a conventional diet therapy, was more effective in the long-term outcome of obesity with regard to weight loss, physical activity, possible eating disorders, and obesity-related complications.

Uppsala Longitudinal Study of Childhood Obesity: protocol description

BACKGROUND AND OBJECTIVE

The prevalence of childhood obesity has risen considerably on a global scale during the past decades, and the condition is associated with increased risk of morbidity. The objective is to describe the Uppsala Longitudinal Study of Childhood Obesity (ULSCO) cohort, including some baseline data, and outline addressed research areas that aim at identifying factors implicated in and contributing to development of obesity and obesity-related diseases, including type 2 diabetes.

METHODS

Severely obese and lean control subjects are examined at enrollment and at subsequent annual visits by using detailed questionnaires, anthropometric measurements, indirect calorimetry, and functional tests such as oral glucose tolerance tests. Some subjects undergo additional characterization with MRI, subcutaneous fat biopsies, frequent blood sampling, and hyperglycemic clamps. Biological samples are obtained and stored in a biobank.

RESULTS

Active recruitment started in 2010, and standard operating procedures have been established. A high participation rate and annual follow-ups have resulted in a cohort exceeding 200 subjects, including 45 lean controls (as of October 2013). Initial research focus has been on traits of the metabolic syndrome, hyperinsulinemia and identifying risk factors for type 2 diabetes.

CONCLUSIONS

The ULSCO cohort serves as an important resource in defining and understanding factors contributing to childhood obesity and development of obesity-related diseases. Given the comprehensive characterization of the cohort, factors contributing to disease development and progression can be identified. Such factors are further evaluated for their mechanistic role and significance, and noncommunicable metabolic diseases are especially addressed and considered.