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1.
J Acoust Soc Am ; 155(3): 1916-1927, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38456734

RESUMO

Speech quality is one of the main foci of speech-related research, where it is frequently studied with speech intelligibility, another essential measurement. Band-level perceptual speech intelligibility, however, has been studied frequently, whereas speech quality has not been thoroughly analyzed. In this paper, a Multiple Stimuli With Hidden Reference and Anchor (MUSHRA) inspired approach was proposed to study the individual robustness of frequency bands to noise with perceptual speech quality as the measure. Speech signals were filtered into thirty-two frequency bands with compromising real-world noise employed at different signal-to-noise ratios. Robustness to noise indices of individual frequency bands was calculated based on the human-rated perceptual quality scores assigned to the reconstructed noisy speech signals. Trends in the results suggest the mid-frequency region appeared less robust to noise in terms of perceptual speech quality. These findings suggest future research aiming at improving speech quality should pay more attention to the mid-frequency region of the speech signals accordingly.


Assuntos
Percepção da Fala , Humanos , Mascaramento Perceptivo , Ruído/efeitos adversos , Inteligibilidade da Fala , Acústica da Fala
2.
Diabetes Obes Metab ; 22(12): 2305-2315, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32734691

RESUMO

AIM: To investigate whether the genetic risk score (GRS) for lean body mass (LBM) modified the effects of weight-loss diets on changes in appetite and adiposity among overweight and obese individuals. PARTICIPANTS AND METHODS: In the 2-year Preventing Overweight Using Novel Dietary Strategies (POUNDS Lost) trial, we included 692 adults who were randomly assigned to one of four diets varying in macronutrient intake. A GRS was calculated using five single nucleotide polymorphisms associated with LBM. RESULTS: The LBM-GRS was not associated with the baseline LBM measured by dual-energy x-ray absorptiometry in a subgroup (50%) of the study population. We found that the LBM-GRS had significantly different associations with changes in appetite from baseline to 6 months according to low- or high-fat diet group (P-interaction < 0.001, 0.021, 0.005 and 0.024 for total appetite score, hunger, fullness and prospective consumption, respectively). Lower LBM-GRS (indicating a greater genetic predisposition to LBM) was associated with greater decreases in the total appetite score (P < 0.001), hunger (P = 0.01), fullness (P = 0.001) and prospective consumption (P = 0.019) in participants in the low-fat diet group, whereas no significant associations with these appetite measures were observed in the high-fat diet group. In addition, lower LBM-GRS was associated with greater reduction in body weight (P = 0.003) and waist circumference (P = 0.011) among participants in the low-fat diet group, while no associations were observed in the high-fat diet group. The interactions attenuated, along with weight regain, from 6 months to 2 years. CONCLUSIONS: Our findings suggest that genetic variation in LBM may be differentially associated with appetite changes, and may subsequently be related to changes in body weight and waist circumference, according to dietary fat intake.


Assuntos
Apetite , Redução de Peso , Adulto , Apetite/genética , Índice de Massa Corporal , Dieta Redutora , Humanos , Sobrepeso , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Redução de Peso/genética
3.
J Acoust Soc Am ; 148(5): 3348, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33261399

RESUMO

Objective metrics, such as the perceptual evaluation of speech quality (PESQ), short-time objective intelligibility (STOI), and signal-to-distortion ratio (SDR), are often used for evaluating speech. These metrics are intrusive since they require a reference (clean) speech signal to complete the evaluation. The need for a reference signal reduces the practicality of these metrics, since a clean reference signal is not typically available during real-world testing. In this paper, a two-stage approach is presented that estimates the objective score of these intrusive metrics in a non-intrusive manner, which enables testing in real-world environments. More specifically, objective score estimation is treated as a machine-learning problem, and the use of speech-enhancement residuals and convolutional long short-term memory (SER-CL) networks is proposed to blindly estimate the objective scores (i.e., PESQ, STOI, and SDR) of various speech signals. The approach is evaluated in simulated and real environments that contain different combinations of noise and reverberation. The results reveal that the proposed approach is a reasonable alternative for evaluating speech, where it performs well in terms of accuracy and correlation. The proposed approach also outperforms comparison approaches in several environments.


Assuntos
Inteligibilidade da Fala , Percepção da Fala , Memória de Curto Prazo , Ruído/efeitos adversos , Razão Sinal-Ruído
4.
Int J Obes (Lond) ; 42(11): 1845-1852, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30254362

RESUMO

BACKGROUND: Decreasing selection and consumption of sodium and added sugars in the school cafeteria setting is important to provide optimal nutrition to children. OBJECTIVE: The ofjective of this study is to determine whether Louisiana (LA) Health, a school-based obesity prevention intervention, could successfully reduce children's selection and consumption of sodium and added sugars during school lunches vs. the control group. DESIGN: Food selection, consumption, and plate waste from student lunches (3 consecutive days) in 33 public schools in rural Louisiana were collected and analyzed using the digital photography of foods method at baseline and after a 28-month obesity prevention intervention (LA Health) beginning in 4th-6th grade (87% of children received free or reduced cost lunch). Selection and consumption of energy, added sugar, and sodium was objectively measured using digital photography of foods. Mixed models, including Race and BMI, were used to determine whether change in selection and consumption differed by group. RESULTS: Sodium decreased for selection (- 233.1 ± 89.4 mg/lunch, p = 0.04) and consumption (- 206.3 ± 65.9, mg/lunch) in the intervention (vs. control) by month 18, and in consumption by month 28 (- 153.5 ± 66.9 mg/lunch, p = 0.03). Change in added sugar consumption decreased in the intervention (vs. control) at month 18 (- 3.7 ± 1.6, p = 0.05) and at month 28 (- 3.5 ± 1.6 tsp/lunch, p = 0.05). CONCLUSIONS: LA Health decreased the amount of added sugar and sodium selected and consumed, but not plate waste, by month 28. Results highlight the importance of long-term interventions and policies targeting provision and selection to improve dietary patterns in children, with less focus on plate waste.


Assuntos
Serviços de Alimentação/estatística & dados numéricos , Almoço , Política Nutricional , Serviços de Saúde Escolar , Sódio , Açúcares , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Feminino , Humanos , Los Angeles/epidemiologia , Masculino , Estado Nutricional , Valor Nutritivo , Instituições Acadêmicas , Sódio/efeitos adversos , Estudantes , Açúcares/efeitos adversos
5.
J Nutr ; 147(3): 439-444, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28148682

RESUMO

Background: The melanocortin-4 receptor (MC4R) plays a pivotal role in the regulation of appetite and eating behavior. Variants in the MC4R gene have been related to appetite and obesity.Objective: We aimed to examine whether weight-loss diets modified the effect of the "obesity-predisposing" MC4R genotype on appetite-related measures in a randomized controlled trial.Methods: A total of 811 overweight and obese subjects [25 ≤ body mass index (BMI; kg/m2) ≤ 40] aged 30-70 y were included in the 2-y POUNDS Lost (Preventing Overweight Using Novel Dietary Strategies) trial. We genotyped MC4R rs7227255 in 735 overweight adults and assessed appetite-related characteristics, including craving, fullness, hunger, and prospective consumption, as well as a composite appetite score. We examined the effects of the genotype-by-weight-loss diet intervention interaction on appetite variables by using general linear models in both the whole population and in white participants only.Results: We found that dietary protein intake (low compared with high: 15% of energy compared with 25% of energy, respectively) significantly modified MC4R genetic effects on changes in appetite score and craving (P-interaction = 0.03 and 0.02, respectively) at 2 y, after adjustment for age, sex, ethnicity, baseline BMI, weight change, and baseline perspective phenotype. The obesity-predisposing A allele was associated with a greater increase in overall appetite score (ß = 0.10, P = 0.05) and craving (ß = 0.13, P = 0.008) compared with the non-A allele among participants who consumed a high-protein diet. MC4R genotype did not modify the effects of fat or carbohydrate intakes on appetite measures. Similar interaction patterns were observed in whites.Conclusion: Our data suggest that individuals with the MC4R rs7227255 A allele rather than the non-A allele might experience greater increases in appetite and food craving when consuming a high-protein weight-loss diet. This trial was registered at clinicaltrials.gov as NCT00072995.


Assuntos
Apetite/genética , Fissura/efeitos dos fármacos , Proteínas Alimentares/farmacologia , Genótipo , Receptor Tipo 4 de Melanocortina/metabolismo , Adulto , Idoso , Apetite/efeitos dos fármacos , Proteínas Alimentares/administração & dosagem , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade , Receptor Tipo 4 de Melanocortina/genética
6.
J Acoust Soc Am ; 141(6): 4668, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28679243

RESUMO

Time-frequency masking is a common solution for the single-channel source separation (SCSS) problem where the goal is to find a time-frequency mask that separates the underlying sources from an observed mixture. An estimated mask is then applied to the mixed signal to extract the desired signal. During signal reconstruction, the time-frequency-masked spectral amplitude is combined with the mixture phase. This article considers the impact of replacing the mixture spectral phase with an estimated clean spectral phase combined with the estimated magnitude spectrum using a conventional model-based approach. As the proposed phase estimator requires estimated fundamental frequency of the underlying signal from the mixture, a robust pitch estimator is proposed. The upper-bound clean phase results show the potential of phase-aware processing in single-channel source separation. Also, the experiments demonstrate that replacing the mixture phase with the estimated clean spectral phase consistently improves perceptual speech quality, predicted speech intelligibility, and source separation performance across all signal-to-noise ratio and noise scenarios.


Assuntos
Acústica , Ruído/efeitos adversos , Processamento de Sinais Assistido por Computador , Acústica da Fala , Medida da Produção da Fala/métodos , Qualidade da Voz , Feminino , Análise de Fourier , Humanos , Masculino , Razão Sinal-Ruído , Espectrografia do Som , Fatores de Tempo
7.
J Acoust Soc Am ; 138(3): 1399-407, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26428778

RESUMO

As a means of speech separation, time-frequency masking applies a gain function to the time-frequency representation of noisy speech. On the other hand, nonnegative matrix factorization (NMF) addresses separation by linearly combining basis vectors from speech and noise models to approximate noisy speech. This paper presents an approach for improving the perceptual quality of speech separated from background noise at low signal-to-noise ratios. An ideal ratio mask is estimated, which separates speech from noise with reasonable sound quality. A deep neural network then approximates clean speech by estimating activation weights from the ratio-masked speech, where the weights linearly combine elements from a NMF speech model. Systematic comparisons using objective metrics, including the perceptual evaluation of speech quality, show that the proposed algorithm achieves higher speech quality than related masking and NMF methods. In addition, a listening test was performed and its results show that the output of the proposed algorithm is preferred over the comparison systems in terms of speech quality.


Assuntos
Percepção da Fala/fisiologia , Adulto , Algoritmos , Feminino , Humanos , Masculino , Modelos Biológicos , Rede Nervosa/fisiologia , Ruído , Ruído dos Transportes , Mascaramento Perceptivo/fisiologia , Razão Sinal-Ruído , Espectrografia do Som/métodos , Acústica da Fala , Adulto Jovem
8.
J Acoust Soc Am ; 136(2): 892-902, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25096123

RESUMO

This study proposes an approach to improve the perceptual quality of speech separated by binary masking through the use of reconstruction in the time-frequency domain. Non-negative matrix factorization and sparse reconstruction approaches are investigated, both using a linear combination of basis vectors to represent a signal. In this approach, the short-time Fourier transform (STFT) of separated speech is represented as a linear combination of STFTs from a clean speech dictionary. Binary masking for separation is performed using deep neural networks or Bayesian classifiers. The perceptual evaluation of speech quality, which is a standard objective speech quality measure, is used to evaluate the performance of the proposed approach. The results show that the proposed techniques improve the perceptual quality of binary masked speech, and outperform traditional time-frequency reconstruction approaches.


Assuntos
Ruído/efeitos adversos , Mascaramento Perceptivo , Processamento de Sinais Assistido por Computador , Acústica da Fala , Inteligibilidade da Fala , Percepção da Fala , Qualidade da Voz , Estimulação Acústica , Algoritmos , Audiometria da Fala , Teorema de Bayes , Análise de Fourier , Humanos , Modelos Lineares , Redes Neurais de Computação , Medida da Produção da Fala , Fatores de Tempo
9.
Appetite ; 61(1): 77-84, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23154216

RESUMO

Recent changes in nutrition standards for the National School Lunch and School Breakfast Programs assume that modification of the nutritional serving practices of school cafeterias will result in improved childhood nutrition in the school environment. The primary aim of this paper is to summarize the findings from two recent cluster randomized controlled trials (Wise Mind and LA Health) that tested the hypothesis that modification of school cafeteria environments, including changes in nutrition standards, would yield beneficial changes in childhood nutrition and healthy eating in the school lunch environment. A secondary aim was to investigate the association of participant characteristics and changes in nutrition and healthy eating. A third aim was to investigate the relationships between the food intake of children and: (1) foods selected by the children and (2) food that was uneaten during the lunch meal (plate waste). The studies used similar approaches for modifying the school cafeteria environment and both studies used the digital photography method to measure changes in food intake, food selection, and plate waste. Both studies reported significant improvements in childhood nutrition, and the LA Health study reported improved healthy eating, following introduction of the cafeteria modification program in comparison to baseline and/or control arms. These studies confirm the hypothesis that interventions that modify the school cafeteria environment can beneficially impact childhood nutrition.


Assuntos
Comportamento Alimentar , Serviços de Alimentação/normas , Estado Nutricional , Valor Nutritivo , Adolescente , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Análise por Conglomerados , Gorduras na Dieta/análise , Proteínas Alimentares/análise , Ingestão de Energia , Feminino , Seguimentos , Preferências Alimentares , Alimentos Orgânicos , Humanos , Los Angeles , Masculino , Obesidade/prevenção & controle , Fotografação , Instituições Acadêmicas
10.
N Engl J Med ; 360(9): 859-73, 2009 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-19246357

RESUMO

BACKGROUND: The possible advantage for weight loss of a diet that emphasizes protein, fat, or carbohydrates has not been established, and there are few studies that extend beyond 1 year. METHODS: We randomly assigned 811 overweight adults to one of four diets; the targeted percentages of energy derived from fat, protein, and carbohydrates in the four diets were 20, 15, and 65%; 20, 25, and 55%; 40, 15, and 45%; and 40, 25, and 35%. The diets consisted of similar foods and met guidelines for cardiovascular health. The participants were offered group and individual instructional sessions for 2 years. The primary outcome was the change in body weight after 2 years in two-by-two factorial comparisons of low fat versus high fat and average protein versus high protein and in the comparison of highest and lowest carbohydrate content. RESULTS: At 6 months, participants assigned to each diet had lost an average of 6 kg, which represented 7% of their initial weight; they began to regain weight after 12 months. By 2 years, weight loss remained similar in those who were assigned to a diet with 15% protein and those assigned to a diet with 25% protein (3.0 and 3.6 kg, respectively); in those assigned to a diet with 20% fat and those assigned to a diet with 40% fat (3.3 kg for both groups); and in those assigned to a diet with 65% carbohydrates and those assigned to a diet with 35% carbohydrates (2.9 and 3.4 kg, respectively) (P>0.20 for all comparisons). Among the 80% of participants who completed the trial, the average weight loss was 4 kg; 14 to 15% of the participants had a reduction of at least 10% of their initial body weight. Satiety, hunger, satisfaction with the diet, and attendance at group sessions were similar for all diets; attendance was strongly associated with weight loss (0.2 kg per session attended). The diets improved lipid-related risk factors and fasting insulin levels. CONCLUSIONS: Reduced-calorie diets result in clinically meaningful weight loss regardless of which macronutrients they emphasize. (ClinicalTrials.gov number, NCT00072995.)


Assuntos
Dieta com Restrição de Carboidratos , Dieta com Restrição de Gorduras , Dieta Redutora/métodos , Obesidade/dietoterapia , Redução de Peso , Pressão Sanguínea , Peso Corporal , Doenças Cardiovasculares , Colesterol/sangue , Aconselhamento , Diabetes Mellitus , Gorduras na Dieta/administração & dosagem , Ingestão de Energia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Obesidade/terapia , Cooperação do Paciente , Fatores de Risco , Saciação , Circunferência da Cintura
11.
Appetite ; 58(3): 806-13, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22329987

RESUMO

The Power of Food Scale (PFS) is a new measure that assesses the drive to consume highly palatable food in an obesogenic food environment. The data reported in this investigation evaluate whether the PFS moderates state cravings, control beliefs, and brain networks of older, obese adults following either a short-term post-absorptive state, in which participants were only allowed to consume water, or a short-term energy surfeit treatment condition, in which they consumed BOOST®. We found that the short-term post-absorptive condition, in which participants consumed water only, was associated with increases in state cravings for desired food, a reduction in participants' confidence related to the control of eating behavior, and shifts in brain networks that parallel what is observed with other addictive behaviors. Furthermore, individuals who scored high on the PFS were at an increased risk for experiencing these effects. Future research is needed to examine the eating behavior of persons who score high on the PFS and to develop interventions that directly target food cravings.


Assuntos
Apetite , Encéfalo/fisiologia , Dieta/psicologia , Preferências Alimentares/psicologia , Obesidade/psicologia , Percepção , Controles Informais da Sociedade , Idoso , Apetite/fisiologia , Comportamento Aditivo/fisiopatologia , Comportamento Aditivo/psicologia , Impulso (Psicologia) , Ingestão de Energia , Comportamento Alimentar/fisiologia , Comportamento Alimentar/psicologia , Feminino , Preferências Alimentares/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/etiologia , Obesidade/fisiopatologia , Período Pós-Prandial , Autoeficácia , Paladar , Água
12.
Proc Natl Acad Sci U S A ; 106(47): 19901-5, 2009 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-19717430

RESUMO

I reject the Darwinian assumption that larvae and their adults evolved from a single common ancestor. Rather I posit that, in animals that metamorphose, the basic types of larvae originated as adults of different lineages, i.e., larvae were transferred when, through hybridization, their genomes were acquired by distantly related animals. "Caterpillars," the name for eruciforms with thoracic and abdominal legs, are larvae of lepidopterans, hymenopterans, and mecopterans (scorpionflies). Grubs and maggots, including the larvae of beetles, bees, and flies, evolved from caterpillars by loss of legs. Caterpillar larval organs are dismantled and reconstructed in the pupal phase. Such indirect developmental patterns (metamorphoses) did not originate solely by accumulation of random mutations followed by natural selection; rather they are fully consistent with my concept of evolution by hybridogenesis. Members of the phylum Onychophora (velvet worms) are proposed as the evolutionary source of caterpillars and their grub or maggot descendants. I present a molecular biological research proposal to test my thesis. By my hypothesis 2 recognizable sets of genes are detectable in the genomes of all insects with caterpillar grub- or maggot-like larvae: (i) onychophoran genes that code for proteins determining larval morphology/physiology and (ii) sequentially expressed insect genes that code for adult proteins. The genomes of insects and other animals that, by contrast, entirely lack larvae comprise recognizable sets of genes from single animal common ancestors.


Assuntos
Evolução Biológica , Hibridização Genética , Larva/fisiologia , Metamorfose Biológica/fisiologia , Modelos Genéticos , Filogenia , Animais , Padronização Corporal/genética , Fósseis , Lepidópteros/anatomia & histologia , Lepidópteros/fisiologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-35010751

RESUMO

The origins of theories specifying dietary restraint as a cause of eating disorders can be traced to the 1970s. This paper will present an overview of the origins of dietary restraint theories and a brief historical review of evidence will be summarized. Recent research will be presented, including the results from the CALERIE Phase 1 study, as well as CALERIE Phase 2, which were NIH-sponsored randomized controlled trials. CALERIE 2 provided a test of the effect of two years of caloric restriction (CR) on the development of eating disorder syndromes and symptoms in comparison to a control group that did not alter eating behavior or body weight. The intervention was effective for inducing a chronic (two-year) reduction in total energy expenditure and increased dietary restraint but did not increase symptoms of eating disorders. The results of this recent investigation and other studies have not provided experimental support for conventional dietary restraint theories of eating disorders. These findings are discussed in terms of potential revisions of dietary restraint theory, as well as the implications for a paradigm shift in public health messaging related to dieting.


Assuntos
Restrição Calórica , Transtornos da Alimentação e da Ingestão de Alimentos , Dieta , Comportamento Alimentar , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Humanos , Saúde Pública
14.
Front Robot AI ; 9: 1011327, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388259

RESUMO

Previous research in human-robot interaction has explored using robots to increase objective and hedonic aspects of well-being and quality of life, but there is no literature on how robots might be used to support eudaimonic aspects of well-being (such as meaning in life). A sense of meaning has been shown to positively affect health and longevity. We frame our study around the Japanese concept of ikigai, which is widely used with Japanese older adults to enhance their everyday lives, and is closely related to the concept of eudaimonic well-being (EWB) known in Western countries. Using a mixed-methods and exploratory approach, including interviews with 17 older adults and the collection of 100 survey responses, we explored how older adults in the US experience a sense of meaning, and if and how a social robot could be used to help foster this sense. We find that meaning for older adults is often obtained by helping others, through family connections, and/or through activities of daily life, and that sources of meaning often differ based on the older adults' living situation. Assessing how meaning compares to happiness and social connection, we highlight general similarities and differences, and also find that living situation influences older adults' sources of happiness, desire for social connection, and barriers to well-being, in addition to companionship and happiness having a weaker correlation with meaning for those who live alone than for those who live with others. Additionally, we evaluated initial perceptions of a social robot (QT) meant to enhance ikigai and overall well-being, finding mostly positive perceptions, though those who live alone also reported being less willing to adopt a social robot into their homes. Using both data collected on older adults' meaning and the potential use of QT to support meaning, we make several design recommendations with regards to using robots to enhance ikigai, such as by prompting daily reflecting, enhancing family bonds, and suggesting new experiences and volunteer opportunities.

15.
Diabetes ; 71(5): 934-944, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35202470

RESUMO

To examine associations between sleep disturbance and changes in weight and body composition and the mediating role of changes of appetite and food cravings in the Preventing Overweight Using Novel Dietary Strategies (POUNDS Lost) 2-year weight-loss diet intervention trial, this study included 810 overweight or obese individuals with baseline sleep disturbance assessment who were randomly assigned one of four diets varying in macronutrient composition. Changes in body weight and fat distribution were assessed by DEXA and computed tomography during the 2-year intervention. Participants were asked to provide sleep disturbance levels (no, slight, moderate, or great) at baseline and to recall their sleep disturbances since last visit at 6, 12, 18, and 24 months. Weight loss during the first 6 months was followed by 1.5 years of steady weight regain. Participants with greater sleep disturbance from baseline to 6 months showed significant losses of body weight (Ptrend <0.001) and waist circumference (Ptrend = 0.002) at 6 months, after multivariate adjustment. Compared with individuals without sleep disturbance at all from baseline to 6 months, those with slight, moderate, or great sleep disturbance showed an elevated risk of failure to lose weight (-5% or more loss) at 6 months, when the maximum weight loss was achieved, with an odds ratio of 1.24 (95% CI 0.87, 1.78), 1.27 (95% CI 0.75, 2.13), or 3.12 (95% CI 1.61, 6.03), respectively. In addition, we observed that the repeatedly measured levels of sleep disturbance over 2 years were inversely associated with the overall weight loss rate (weight changes per 6 months) (Ptrend <0.001). Further, sleep disturbances during weight loss from baseline to 6 months and weight regain from 6 months to 24 months were significantly predictive of total fat, total fat mass percent, and trunk fat percent changes during the 2 years. Our results also indicated that food cravings for carbohydrates/starches, fast food fats, and sweets; cravings, prospective consumption, hunger of appetite measurements; and dietary restraint, disinhibition, and hunger subscales measured at 6 months significantly mediated the effects of sleep disturbance on weight loss. In conclusion, our results suggested that more severe sleep disturbance during weight loss was associated with an elevated risk of failure to lose weight during the dietary intervention. Food cravings and eating behaviors may partly mediate these associations.


Assuntos
Sobrepeso , Redução de Peso , Composição Corporal , Índice de Massa Corporal , Dieta Redutora/métodos , Ingestão de Energia , Humanos , Estudos Prospectivos , Sono , Aumento de Peso , Redução de Peso/fisiologia
16.
Clin Trials ; 8(2): 155-64, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21385788

RESUMO

BACKGROUND: objective measures are needed to quantify dietary adherence during caloric restriction (CR) while participants are freeliving. One method to monitor adherence is to compare observed weight loss to the expected weight loss during a prescribed level of CR. Normograms (graphs) of expected weight loss can be created from mathematical modeling of weight change to a given level of CR, conditional on the individual's set of baseline characteristics. These normograms can then be used by counselors to help the participant adhere to their caloric target. PURPOSE: (1) To develop models of weight loss over a year of caloric restriction-given demographics, and well-defined measurements of body mass index, total daily energy expenditure (TDEE) and %CR. (2) To utilize these models to develop normograms, given the level of caloric restriction prescribed, and measures of these variables. METHODS: Seventy-seven individuals completing a 6-12-month caloric restriction intervention (CALERIE) at three sites (Pennington Biomedical Research Center, Tufts University, and Washington University) and had body weight and body composition measured frequently. Energy intake (and %CR) was estimated from TDEE (by doubly labeled water) and body composition (by DXA) at baseline and months 1, 3, 6, and 12. Bodyweight was modeled to determine the predictors and distribution of the expected trajectory of percent weight change over 12 months of CR. RESULTS: As expected, CR was related to change in body weight. Controlling for time-varying measures, initially simple models of the functional form indicated that the trajectory of percent weight change was predicted by a nonlinear function of age, TDEE, %CR, and sex. Using these estimates, normograms for the weight change were developed. Our model estimates that the mean weight loss (% change from baseline weight) for an individual adherent to a 25% CR regimen is -10.9 ± 6.3% for females and -13.9 + 6.4% for men after 12 months. LIMITATIONS: There are several limitations. Sample sizes are small (n = 77), and, by design, the protocols, including prescribed CR, for the interventions differed by site, and not all subjects completed a year of follow-up. In addition, the inclusion of subjects by age and initial BMI was constricted, so that these results may not generalize to other populations including older and obese subjects. CONCLUSIONS: The trajectory of percent weight change during CR interventions in the presence of well-measured covariates can be modeled using simple nonlinear functions, and is related level of CR, the percent change in TDEE, gender, and age. Displayed on a normogram, individually tailored trajectories can be used by counselors and participants to monitor weight loss and adherence to a CR regimen.


Assuntos
Restrição Calórica , Nomogramas , Cooperação do Paciente , Adulto , Fatores Etários , Composição Corporal , Índice de Massa Corporal , Metabolismo Energético , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Redução de Peso
17.
Obesity (Silver Spring) ; 29(4): 654-661, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33759385

RESUMO

OBJECTIVE: This study aimed to determine the medical cost impact and return on investment (ROI) of a large, commercial, digital, weight-management intensive lifestyle intervention (ILI) program (Real Appeal). METHODS: Participants in this program were compared with a control group matched by age, sex, geographic region, health risk, baseline medical costs, and chronic conditions. Medical costs were defined as the total amount paid for all medical expenses, inclusive of both the insurers' and the study participants' responsibility. RESULTS: In the 3 years following program registration, the intent-to-treat (ITT) cohort had significantly lower medical expenditures than the matched controls, with an average of -$771 or 12% lower costs (P = 0.002). Among 4,790 ITT participants, a total savings of $3,693,090 compared with total program costs of $1,639,961 translated into a 2.3:1 ROI. Program completers (n = 3,990), who attended more sessions than the overall ITT group, had greater mean weight loss (-4.4%), greater cost savings (-$956 or 14%), and an ROI of 2.0:1 over the 3-year time frame compared with matched controls. CONCLUSIONS: The findings demonstrated that the digital weight-management ILI was associated with a significantly positive ROI. Employers and payers willing to cover the cost of an ILI that produces both weight loss and demonstrated cost benefits can improve health and save money for their population with overweight or obesity.


Assuntos
Redução de Custos/economia , Análise Custo-Benefício/economia , Obesidade/economia , Redução de Peso/fisiologia , Adolescente , Adulto , Estudos de Coortes , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
J Nutr ; 140(9): 1653-60, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20668251

RESUMO

In this study, we examined if children's food selection met the School Meals Initiative (SMI) standards and the recently released Institute of Medicine (IOM) recommendations. Mean food selection, plate waste, and food intake were also examined. Food intake of 2049 4th-6th grade students was measured objectively at lunch over 3 d with digital photography in 33 schools. The percent of children whose food selection met the SMI standards and IOM recommendations for energy (kJ), fat and saturated fat, calcium, iron, and vitamin A and C were calculated. The SMI standards provide lower limits for most nutrients; the IOM provides a range of values, including an upper limit for energy. Seventy-seven percent of children's energy selection met the SMI lower limit, but only 16% of children met the IOM's recommended range and 74% of children exceeded the upper limit. More than 70% of children exceeded the SMI and IOM's saturated fat recommendations. Children selected (mean +/- SD) 3168 +/- 621 kJ, discarded 882 +/- 581 kJ, and consumed 2286 +/- 716 kJ. Children were less likely to discard fat than carbohydrate, resulting in proportionally more fat being consumed. Most children met SMI and IOM recommendations for protein, calcium, iron, and vitamin A. With few exceptions, energy selection was similar among groups of children, but plate waste differed (P < 0.001), resulting in greater energy intake among boys compared with girls, Caucasians compared with African Americans, and heavier compared with lighter children. Children's selection was high in saturated fat and, based on IOM criteria, included excess energy.


Assuntos
Gorduras na Dieta , Ingestão de Energia , Ácidos Graxos , Preferências Alimentares/psicologia , Serviços de Alimentação , Instituições Acadêmicas , Adolescente , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Feminino , Análise de Alimentos , Humanos , Masculino , National Academies of Science, Engineering, and Medicine, U.S., Health and Medicine Division , Política Nutricional , Valor Nutritivo , Estados Unidos
19.
Am J Health Promot ; 24(5): 340-3, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20465148

RESUMO

PURPOSE: To examine the influence of an environmental intervention to prevent excess weight gain in African-American children. DESIGN: Single-group repeated measures. SETTING: The intervention was delivered to a school composed of African-American children. PARTICIPANTS: Approximately 45% (N = 77) of enrolled second through sixth grade students. INTERVENTION: The 18-month intervention was designed to alter the school environment to prevent excess weight gain by making healthier eating choices and physical activity opportunities more available. MEASURES: Body mass index percentile was the primary outcome variable. Body mass index z score was also calculated, and percent body fat, using bioelectrical impedance, was also measured. Total caloric intake (kilocalories) and percent kilocalories from fat, carbohydrate, and protein were measured by digital photography. Minutes of physical activity and sedentary behavior were selfreported. ANALYSIS: Mixed-models analysis was used with covarying baseline values. RESULTS: Boys maintained, whereas girls increased, percent body fat over 18 months (p = .027). All children decreased percent of kilocalories consumed from total and saturated fat and increased carbohydrate intake and self-reported physical activity during the intervention (p < .025). Body mass index z score, sedentary behavior, and total caloric intake were unchanged. CONCLUSION: The program may have resulted in maintenance of percent body fat in boys. The percent body fat in girls steadily increased, despite similar behavioral changes as boys. School-based interventions targeting African-American children should investigate strategies that can be effective across gender.


Assuntos
Negro ou Afro-Americano , Exercício Físico , Comportamento Alimentar , Comportamentos Relacionados com a Saúde , Obesidade/prevenção & controle , Tecido Adiposo , Fatores Etários , Índice de Massa Corporal , Carboidratos da Dieta , Ingestão de Energia , Feminino , Seguimentos , Humanos , Estilo de Vida , Masculino , Projetos Piloto , Fatores de Tempo , Aumento de Peso
20.
J Behav Med ; 33(1): 35-46, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19856202

RESUMO

Research on the conceptualization of adherence to treatment has not addressed a key question: Is adherence best defined as being a uni-dimensional or multi-dimensional behavioral construct? The primary aim of this study was to test which of these conceptual models best described adherence to a weight management program. This ancillary study was conducted as a part of the POUNDS LOST trial that tested the efficacy of four dietary macronutrient compositions for promoting weight loss. A sample of 811 overweight/obese adults was recruited across two clinical sites, and each participant was randomly assigned to one of four macronutrient prescriptions: (1) Low fat (20% of energy), average protein (15% of energy); (2) High fat (40%), average protein (15%); (3) Low fat (20%), high protein (25%); (4) High fat (40%), high protein (25%). Throughout the first 6 months of the study, a computer tracking system collected data on eight indicators of adherence. Computer tracking data from the initial 6 months of the intervention were analyzed using exploratory and confirmatory analyses. Two factors (accounting for 66% of the variance) were identified and confirmed: (1) behavioral adherence and (2) dietary adherence. Behavioral adherence did not differ across the four interventions, but prescription of a high fat diet (vs. a low fat diet) was found to be associated with higher levels of dietary adherence. The findings of this study indicated that adherence to a weight management program was best conceptualized as being multi-dimensional, with two dimensions: behavioral and dietary adherence.


Assuntos
Modelos Psicológicos , Obesidade/dietoterapia , Obesidade/psicologia , Sobrepeso/dietoterapia , Sobrepeso/psicologia , Cooperação do Paciente/psicologia , Comportamento , Estudos de Coortes , Computadores , Dieta , Dieta Redutora/métodos , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
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