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1.
FASEB J ; 38(7): e23579, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38568838

RESUMO

Lifestyle interventions remain the treatment of choice for patients with obesity and metabolic complications, yet are difficult to maintain and often lead to cycles of weight loss and regain (weight cycling). Literature on weight cycling remains controversial and we therefore investigated the association between weight cycling and metabolic complications using preexistent obese mice. Ldlr-/-.Leiden mice received a high-fat diet (HFD) for 20 weeks to induce obesity. Subsequently, weight-cycled mice were switched between the healthy chow diet and HFD for four 2-week periods and compared to mice that received HFD for the total study period. Repeated weight cycling tended to decrease body weight and significantly reduced fat mass, whereas adipose tissue inflammation was similar relative to HFD controls. Weight cycling did not significantly affect blood glucose or plasma insulin levels yet significantly reduced plasma free fatty acid and alanine transaminase/aspartate transaminase levels. Hepatic macrovesicular steatosis was similar and microvesicular steatosis tended to be increased upon weight cycling. Weight cycling resulted in a robust decrease in hepatic inflammation compared to HFD controls while hepatic fibrosis and atherosclerosis development were not affected. These results argue against the postulate that repeated weight cycling leads to unfavorable metabolic effects, when compared to a continuous unhealthy lifestyle, and in fact revealed beneficial effects on hepatic inflammation, an important hallmark of non-alcoholic steatohepatitis.


Assuntos
Fígado , Hepatopatia Gordurosa não Alcoólica , Humanos , Camundongos , Animais , Fígado/metabolismo , Camundongos Obesos , Ciclo de Peso , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/complicações , Inflamação/metabolismo , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL
2.
Eur J Nutr ; 63(3): 965-976, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38265751

RESUMO

PURPOSE: Weight cycling is a phenomenon characterized by fluctuating body weight that is commonly observed in individuals employing intentional weight loss methods. Despite its prevalence, the impact of weight cycling on health remains equivocal. The current investigation aimed to examine the effects of weight cycling on liver health. METHODS: The weight cycling model was established by switching the feeding method of mice between ad libitum (AL) and restricted intake (DR or 60% of AL) of the breeding diet to cause weight gain and weight loss, respectively. The weight cycling model comprised two and a half cycles, with one group terminating the experience during the weight-gain period (S-AL) and the other during the weight-loss period (S-DR). Liver tissue was collected to investigate morphology alterations, apoptosis, lipid metabolism, and mitochondrial homeostasis. RESULTS: The results demonstrated that the termination point of weight cycling affected body weight and hepatic steatosis. All parameters examined in the S-DR mice exhibited a comparable trend to those observed in the DR mice. Notably, S-AL mice showed a significant increase in lipid metabolism-related proteins in the liver compared to AL-fed mice, along with reduced lipid droplets. Moreover, hepatic apoptosis and fibrosis were exacerbated in the S-AL mice compared to AL mice, whereas mitochondrial fusion, biogenesis, and mitophagy were decreased in the S-AL mice. CONCLUSION: Weight cycling ending in weight gain exacerbated hepatic fibrosis, potentially by inducing apoptosis or disrupting mitochondrial homeostasis. Conversely, weight cycling ending in weight loss demonstrated beneficial effects on hepatic health.


Assuntos
Fígado , Ciclo de Peso , Camundongos , Masculino , Animais , Fígado/metabolismo , Cirrose Hepática , Aumento de Peso , Redução de Peso , Camundongos Endogâmicos C57BL , Dieta Hiperlipídica
3.
BMC Public Health ; 24(1): 894, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532390

RESUMO

BACKGROUND: Obesity is a global public health concern. The goal of this study was to see if eating habits could mediate the relationship between psychological distress and weight maintenance in a population with a history of weight cycling. METHODS: A 3-month outpatient intervention consisting of a diet and exercise program was provided to 153 participants. Psychological distress, appetite, and behavior were assessed at the beginning and end of the study. Anthropometric measurements were taken at baseline and six months. RESULTS: After the structural equation model was developed, it was discovered that the psychological status of people with obesity and weight cycling histories correlated with the weight loss outcome effect (three and six months). This effect was mediated by factors related to eating behavior. Associative psychological factors had a direct effect on eating behavior (three months: ß = 0.181, 95% CI: 0.055-0.310; six months: ß = 0.182, 95% CI: 0.039-0.332) and appetite had a direct effect on eating behavior (three months: ß = 0.600, 95% CI: 0.514-0.717; six months: ß = 0.581, 95% CI: 0.457-0.713), both of which were significant (p < 0.01). At three months, psychological distress has a more substantial positive impact on weight change, with eating behavior acting as a partial mediator. At six months, there was no support for appetite's moderating role in eating behavior. CONCLUSIONS: The findings suggest that psychological interventions should be strengthened to improve weight loss effectiveness, particularly in participants with a history of weight cycling, making weight loss more complicated and prone to rebound. CLINICAL TRIAL REGISTRATION: The study has been registered in Clinical Trials (NCT05311462).


Assuntos
Angústia Psicológica , Redução de Peso , Humanos , Manutenção do Peso Corporal , Comportamento Alimentar/psicologia , Obesidade/psicologia , Ciclo de Peso
4.
Qual Health Res ; : 10497323231221666, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38270518

RESUMO

Weight cycling is a likely consequence of striving to lose weight after internalizing body image ideals, making upward social comparisons, and experiencing weight stigma. Despite weight cycling's potential physical and psychological consequences, the interplay of weight cycling, social pressures, and experienced and internalized stigma have not been qualitatively explored. Thus, through in-depth interviews of 36 weight-cycling adults, this study sought to understand how people negotiate weight cycling. Interviews informed the development of a qualitative model of weight cycling, which was derived from a theory-neutral inductive analysis. The model's stages included entering the cycle, undergoing the cycle, and challenging the cycle. Participants were triggered to enter the cycle due to weight stigma caused by social pressures. Within the cycle, interviewees internalized weight stigma and engaged in disordered weight management behaviors. Some participants challenged the cycle by becoming more self-aware and mitigating their toxic dieting behaviors. However, it was very difficult, if not impossible, for many to fully exit weight cycling and the restraints of previous weight management thinking and patterns. Our investigation underscores the seriousness of weight cycling and suggests ways to combat weight cycling on both macro and individual levels. It may also be useful to consider weight cycling as disordered eating in hopes of shifting society's dangerous focus on rapid weight loss.

5.
Br J Nutr ; 129(10): 1827-1839, 2023 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-35610735

RESUMO

The long-term impact of weight cycling on health status, eating habits, physical activity and the lifestyle of former combat sports athletes is still insufficiently explored. Therefore, a novel questionnaire in English, Portuguese, Spanish and Croatian language was constructed. To determine the reliability and the content/face validity, a total of 110 participants filled the questionnaire on two occasions. With the majority of intra-class correlation coefficient values above 0·75, the questionnaire items were shown to be very stable. Additionally, according to κ values, the questionnaire has fair test-retest reliability, with only one coefficient being labelled as poor (Q40 in ESP). All questionnaire sub-scales showed moderate to very good internal consistency when the overall sample was observed (α ranging from 0·605 to 0·802). Poor α values were found only in Godin-Shephard Leisure-Time Physical Activity Questionnaire for CRO and ESP samples. Wilcoxon's signed rank test showed significant differences only in the Mindful Eating Questionnaire sub-scale scores (overall: P = 0·002, effect size = -0·208 [moderate]; CRO: P = 0·005, effect size = 0·303 [moderate]). It can be concluded that the newly developed questionnaire had strong test-retest reliability. Further validity research in a larger sample of former combat sports athletes should be considered.


Assuntos
Exercício Físico , Estilo de Vida , Humanos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Etnicidade
6.
Curr Osteoporos Rep ; 21(1): 77-84, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36542294

RESUMO

PURPOSE OF REVIEW: Obesity is highly prevalent and is associated with bone fragility and fracture. The changing nutrient availability to bone in obesity is an important facet of bone health. The goal of this article is to summarize current knowledge on the effects of carbohydrate and dietary fat availability on bone, particularly in the context of other tissues. RECENT FINDINGS: The skeleton is a primary site for fatty acid and glucose uptake. The trafficking of carbohydrates and fats into tissues changes with weight loss and periods of weight gain. Exercise acutely influences nutrient uptake into bone and may affect nutrient partitioning to bone. Bone cells secrete hormones that signal to the brain and other tissues information about its energetic state, which may alter whole-body nutrient trafficking. There is a critical need for studies to address the changes that metabolic perturbations have on nutrient availability in bone.


Assuntos
Densidade Óssea , Obesidade , Humanos , Obesidade/metabolismo , Gorduras na Dieta/metabolismo , Metabolismo Energético , Nutrientes , Ingestão de Energia
7.
Am J Epidemiol ; 191(6): 1009-1020, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35102370

RESUMO

Pancreatic cancer (PC) is the fourth leading cause of cancer mortality among women in the United States. Obesity is positively associated with PC risk. Current health recommendations focus on weight maintenance for healthy-weight individuals and weight loss for overweight/obese individuals; however, little research has assessed associations between PC risk and changes in weight throughout the life course. Using prospective cohort study data, we examined the relationship between baseline adulthood weight patterns self-reported between 1993 and 1998 and PC risk in 136,834 postmenopausal women with 873 incident PC cases through September 30, 2015, in the Women's Health Initiative. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox proportional hazards models, adjusting for age, smoking habits, heavy alcohol consumption, and body mass index. Compared with women with stable weight, no significant associations were found between steady weight gain (HR = 1.01, 95% CI: 0.83, 1.22), sustained weight loss (HR = 1.26, 95% CI: 0.85, 1.87), or weight cycling patterns (HR = 1.08, 95% CI: 0.89, 1.30) and PC. Results were similar when the outcome definition was restricted to pancreatic adenocarcinoma cases. Overall, we did not find evidence to suggest that weight changes in adulthood significantly impact PC risk among postmenopausal women.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Adulto , Peso Corporal , Feminino , Humanos , Incidência , Obesidade/complicações , Obesidade/epidemiologia , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/etiologia , Pós-Menopausa , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Estados Unidos/epidemiologia , Ciclo de Peso , Aumento de Peso , Redução de Peso , Saúde da Mulher
8.
Br J Nutr ; 128(3): 569-576, 2022 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-34470676

RESUMO

Weight cycling is prevalent in sports/professions with body composition standards, and has been associated with weight management behaviours that may contribute to suboptimal diet quality and weight gain. US Army Soldiers may be at increased risk of weight cycling relative to civilians due to mandated body composition standards. However, the relationship between weight cycling, weight management behaviours, BMI and diet quality among Soldiers is unknown. In this cross-sectional study, 575 Soldiers (89 % enlisted, 90 % male, 23 ± 4 years) at Army installations at Joint Base Elmendorf-Richardson, AK, Joint-Base Lewis McChord, WA, and Fort Campbell, KY completed questionnaires on food frequency, health-related behaviours and history of weight cycling (≥ 3 weight fluctuations ≥ 5 % body weight). Weight cycling was reported by 33 % of Soldiers. Those who reported weight cycling reported higher BMI (27 ± 4 v. 25 ± 3 kg/m2, P < 0·001) and higher prevalence of engaging in weight management behaviours prior to body weight screening but did not report lower dietary quality (Healthy Eating Index-2015 (HEI) scores 59 ± 10 v 59 ± 11, P = 0·46) relative to those who did not report weight cycling. Results of mediation analyses suggested that weight cycling may affect BMI both directly (c' = 1·19, 95 % CI: 0·62, 1·75) and indirectly (ab = 0·45, 95 % CI: 0·19, 0·75), and HEI scores indirectly (ab = 0·69, 95 % CI: 0·20, 1·35) through the adoption of weight management behaviours. Weight cycling is common in Soldiers and is associated with higher BMI and higher prevalence of engaging in weight management behaviours that mediate associations between weight cycling, BMI and diet quality.


Assuntos
Militares , Ciclo de Peso , Masculino , Humanos , Feminino , Índice de Massa Corporal , Estudos Transversais , Dieta , Peso Corporal , Comportamentos Relacionados com a Saúde
9.
Cancer Causes Control ; 32(9): 1029-1038, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34089471

RESUMO

PURPOSE: Weight cycling is common in populations. However, it is unclear whether frequency and magnitude of weight cycling is associated with kidney cancer risk, independent of body mass index (BMI). METHODS: A prospective cohort study followed 85,562 participants from Health Professionals Follow-up Study and Nurses' Health Study (1992-2014). At baseline, participants reported frequency and magnitude of intentional weight loss in the past 4 years. Cox proportional hazard model was used to estimate hazard ratios (HR) and 95% confidence intervals (CI). We also conducted a meta-analysis of all available observational studies including our two cohorts. RESULTS: During 22 years of follow-up, we identified 441 kidney cancer cases. Compared with non-weight cyclers (no attempt of intentional weight loss), severe cyclers (≥ 3 times of intentional weight loss of ≥ 4.5 kg) were at increased kidney cancer risk after adjusting for BMI before weight cycling (pooled multivariable-adjusted HR, 1.78; 95% CI, 1.19, 2.66). Additional adjustment for attained BMI after weight cycling had minimal influence. There was a positive trend between weight cycling by frequency and magnitude and kidney cancer risk (P-trend = 0.01). Moreover, the observed positive association did not differ by subtypes of cyclers (e.g., adiposity status, weight-loss methods). In the meta-analysis, we found a strong positive association between weight cycling and kidney cancer risk (summary relative risk for weight cyclers vs. non-cyclers, 1.51; 95% CI, 1.16, 1.96; I2: 52.2%; 6 studies). CONCLUSION: Frequent substantial weight cycling was associated with increased risk of kidney cancer, independent of BMI. Our study suggests that weight cycling may be an important risk factor for kidney cancer.


Assuntos
Neoplasias Renais , Aumento de Peso , Índice de Massa Corporal , Seguimentos , Humanos , Neoplasias Renais/epidemiologia , Neoplasias Renais/etiologia , Estudos Observacionais como Assunto , Estudos Prospectivos , Fatores de Risco , Redução de Peso
10.
FASEB J ; 34(3): 4732-4748, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32030835

RESUMO

Repeated cycles of weight loss and regain, known as weight cycling, is often seen when people try to lose weight. The exact pathophysiological effects and the underlying mechanisms of weight cycling remain largely unclear. Here, we report that weight cycling induced by alternating feeding mice with a low-fat diet or a high-fat diet in a 1-week switch protocol caused further increased epididymal white adipose tissue (eWAT) weight, preadipocyte proliferation, hepatic inflammation, fasting blood glucose level, and glucose intolerance, compared with the continuously HF-fed mice. Combining the secretory protein database with RNA-sequencing and quantitative PCR (qPCR) results in eWAT, the mRNA levels of several adipokines, including Retn (encoding resistin), were found altered by weight cycling. A transcriptional co-factor Lmo4 was found regulated by weight cycling; Lmo4 enhanced preadipocyte proliferation, in vitro adipogenesis, transcription of Retn, and resistin secretion in 3T3-L1 cells. Primary mouse hepatocytes administrated with recombinant mouse resistin (rm-resistin), or exposed to media from Lmo4-overexpressed 3T3-L1 cells, showed increased inflammatory responses and gluconeogenesis. Furthermore, rm-resistin-injected normal chow-fed mice showed upregulated blood glucose level by increasing gluconeogenesis, and upregulated the hepatic inflammatory responses. Together, our results suggest a regulatory role of Lmo4-resistin signaling in weight cycling, indicating a crosstalk between the adipose tissue and liver.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adipócitos/metabolismo , Gordura Intra-Abdominal/citologia , Gordura Intra-Abdominal/metabolismo , Proteínas com Domínio LIM/metabolismo , Células 3T3-L1 , Proteínas Adaptadoras de Transdução de Sinal/sangue , Proteínas Adaptadoras de Transdução de Sinal/genética , Adipocinas/sangue , Adipocinas/genética , Adipocinas/metabolismo , Tecido Adiposo/imunologia , Tecido Adiposo/metabolismo , Tecido Adiposo Branco/imunologia , Tecido Adiposo Branco/metabolismo , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Western Blotting , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Imuno-Histoquímica , Inflamação/imunologia , Inflamação/metabolismo , Proteínas com Domínio LIM/sangue , Proteínas com Domínio LIM/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Resistina/sangue , Resistina/genética , Resistina/metabolismo , Análise de Sequência de RNA , Aumento de Peso/genética , Aumento de Peso/fisiologia
11.
Eat Weight Disord ; 26(6): 2083-2087, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32816206

RESUMO

PURPOSE: To assess the relationship between multiple weight cycling (WC) and early weight loss (e-WL). METHODS: Using a longitudinal prospective design conducted between May 2017 and November 2019, early weight loss was assessed at month 2 of a weight management programme in 100 adult participants with overweight or obesity, at the Outpatient Clinic of the Department of Nutrition and Dietetics at Beirut Arab University (Lebanon). Weight cycling was defined as intentional weight loss of ≥ 3 kg followed by involuntary weight regain of ≥ 3 kg and participants were then categorized as multiple WC if they had experienced ≥ 2 cycles. RESULTS: Of the 100 participants with a median age of 34.90 (22.94-50.67) years and a median BMI of 35.25 (32.75-39.48) kg/m2, 75 met the criteria for WC and displayed a lower e-WL percentage than those without WC (4.69 ± 2.78% vs. 6.58 ± 2.80%; p = 0.006). Linear regression analysis showed that e-WL was lower by ≈ 2% (ß = - 1.935; 95% CL - 3.221, - 0.648; p = 0.004) in the WC group compared to the non-WC group after adjusting for age, gender and baseline BMI. CONCLUSION: In a 'real-world' clinical setting, multiple WC decreases e-WL rates. New strategies could be adopted for these patients to improve this early clinical outcome, since e-WL predicts longer-term success. LEVEL OF EVIDENCE: III, prospective longitudinal study.


Assuntos
Obesidade , Redução de Peso , Adulto , Índice de Massa Corporal , Humanos , Líbano , Estudos Longitudinais , Pessoa de Meia-Idade , Estudos Prospectivos
12.
Med Health Care Philos ; 24(2): 255-267, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33439383

RESUMO

Based in narrative phenomenology, this article describes an example of how lived time, self and bodily engagement with the social world intertwine, and how our sense of self develops. We explore this through the life story of a woman who lost weight through surgery in the 1970 s and has fought against her own body, food and eating ever since. Our narrative analysis of interviews, reflective notes and email correspondence disentangled two storylines illuminating paradoxes within this long-term weight loss process. Thea's Medical Weight Narrative: From Severely Obese Child to Healthy Adult is her story in context of medicine and obesity treatment and expresses success and control. Thea's Story: The Narrative of Fighting Weight is the experiential story, including concrete examples and quotes, highlighting bodily struggles and the inescapable ambiguity of being and having one's body. The two storylines coexist and illuminate paradoxes within the weight loss surgery narrative, connected to meaningful life events and experiences, eating practices and relationships with important others. Surgery was experienced as lifesaving, yet the surgical transformation did not suffice, because it did not influence appetite or, desire for food in the long run. In the medical narrative of transforming the body by repair, a problematic relationship with food did not fit into the plot.


Assuntos
Cirurgia Bariátrica , Obesidade Mórbida , Adulto , Criança , Família , Feminino , Humanos , Narração , Obesidade Mórbida/cirurgia
13.
Am J Physiol Endocrinol Metab ; 317(5): E863-E870, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31322412

RESUMO

We studied the effects of multiple cycles of weight loss and regain on the defended body weight in rats. Thirty-six male Wistar rats were divided into three weight-matched groups: weight cyclers (n = 18), ad libitum-fed controls (n = 9), and maturity controls (n = 9). Cyclers underwent four rounds of 20% weight loss from 50% caloric restriction, each cycle followed by recovery to stable plateau weight on ad libitum feeding. Controls ate ad libitum. Maturity controls ate ad libitum and then weight cycled the final two rounds to evaluate the effect of age in later cycles. Cyclers' postdiet plateau weight became progressively lower than that of controls. With each weight loss, ghrelin increased, while insulin and leptin decreased; the magnitude of these changes did not differ across cycles. After four rounds, cyclers' weight (504 ± 7 vs. 540 ± 22 g; P < 0.05) and percent body fat (11.7 vs. 15.2%; P < 0.05) were lower than in controls. After a 4-mo follow-up period of ad libitum feeding, cyclers maintained a lower total fat-pad mass versus controls (8.6 ± 0.5 vs. 15.9 ± 3.6 g; P < 0.01) and a lower glucose area-under-the-curve on oral glucose tolerance tests (P < 0.05). Repeated weight-loss cycles exerted positive effects, durably lowering defended levels of body adiposity and improving glucose tolerance.


Assuntos
Peso Corporal/fisiologia , Redução de Peso/fisiologia , Adiposidade , Animais , Composição Corporal , Restrição Calórica , Dieta Redutora , Grelina/metabolismo , Teste de Tolerância a Glucose , Insulina/sangue , Leptina/sangue , Masculino , Ratos , Ratos Wistar
14.
Int J Gynecol Cancer ; 29(9): 1361-1371, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31451560

RESUMO

PURPOSE: Weight cycling, defined as intentional weight loss followed by unintentional weight regain, may attenuate the benefit of intentional weight loss on endometrial cancer risk. We summarized the literature on intentional weight loss, weight cycling after intentional weight loss, bariatric surgery, and endometrial cancer risk. METHODS: A systematic search was conducted using MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases published between January 2000 and November 2018. We followed Preferred Reporting Items of Systematic Reviews and Meta-analysis (PRISMA) guidelines. We qualitatively summarized studies related to intentional weight loss and weight cycling due to the inconsistent definition, and quantitatively summarized studies when bariatric surgery was the mechanism of intentional weight loss. RESULTS: A total of 127 full-text articles were reviewed, and 13 were included (bariatric surgery n=7, self-reported intentional weight loss n=2, self-reported weight cycling n=4). Qualitative synthesis suggested that, compared with stable weight, self-reported intentional weight loss was associated with lower endometrial cancer risk (RR range 0.61-0.96), whereas self-reported weight cycling was associated with higher endometrial cancer risk (OR range 1.07-2.33). The meta-analysis yielded a 59% lower risk of endometrial cancer following bariatric surgery (OR 0.41, 95% CI 0.22 to 0.74). CONCLUSIONS: Our findings support the notion that intentional weight loss and maintenance of a stable, healthy weight can lower endometrial cancer risk. Strategies to improve awareness and maintenance of weight loss among women with obesity are needed to reduce endometrial cancer risk.


Assuntos
Neoplasias do Endométrio/epidemiologia , Aumento de Peso , Redução de Peso , Cirurgia Bariátrica/estatística & dados numéricos , Feminino , Humanos , Risco
15.
Int J Sport Nutr Exerc Metab ; 29(4): 441­452, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30299200

RESUMO

Combat sport athletes typically engage in a process called making weight, characterized by rapid weight loss (RWL) and subsequent rapid weight gain (RWG) in the days preceding competition. These practices differ across each sport, but no systematic comparison of the size of the changes in body mass exists. The aim was to determine the magnitude of RWL and RWG in combat sport athletes preparing for competition. The review protocol was preregistered with PROSPERO (CRD42017055279). In eligible studies, athletes prepared habitually with a RWL period ≤7 days preceding competition. An electronic search of EBSCOhost (CINAHL Plus, MEDLINE, and SPORTDiscus) and PubMed Central was performed up to July 2018. Sixteen full-text studies (total 4,432 participants; 156 females and 4,276 males) were included, providing data from five combat sports (boxing, judo, mixed martial arts, taekwondo, and wrestling). Three studies reported RWL and 14 studies reported RWG. Duration permitted for RWG ranged 3-32 hr. The largest changes in body mass occurred in two separate mixed martial arts cohorts (RWL: 7.4 ± 1.1 kg [∼10%] and RWG: 7.4 ± 2.8 kg [11.7% ± 4.7%]). The magnitude of RWG appears to be influenced by the type of sport, competition structure, and recovery duration permitted. A cause for concern is the lack of objective data quantifying the magnitude of RWL. There is insufficient evidence to substantiate the use of RWG as a proxy for RWL, and little data are available in females. By engaging in RWG, athletes are able to exploit the rules to compete up to three weight categories higher than at the official weigh-in.


Assuntos
Atletas , Comportamento Competitivo , Aumento de Peso , Redução de Peso , Peso Corporal , Boxe , Feminino , Humanos , Masculino , Artes Marciais , Luta Romana
16.
Int J Sport Nutr Exerc Metab ; 29(5): 532-538, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30975001

RESUMO

Fasting, skipping meals, and dehydration are common methods of rapid weight loss used prior to competition in weight category sports. This study examines coaches' attitudes, perceptions, and practices regarding rapid weight loss among judo and taekwondo athletes. A convenience sample of experienced coaches and trainers (n = 68) completed structured questionnaires. Participants in this study were 33.8 ± 9.3 years old; 57 were males and 11 were females; and 59% were certified coaches, with 71% reporting over 20 years of involvement in sports and 68% having more than 10 years of teaching experience. The majority (90%) reported that they usually supervised athletes through the weight loss process. Interventions for weight loss began at 12.7 ± 1.9 years of age, with a recommended precompetition weight loss duration of 16.2 ± 8.2 days and an average reduction of 1.5 ± 0.7 kg. The majority of the responders (92%) recommended that their athletes practice gradual weight loss methods using a combination of dehydration or increased physical activity (80.3%), sweat suits (50.8%), restricted fluid intake (39.3%), training in heated rooms (27%), and sauna (26.2%). Recommendations of spitting (27.8%) or using laxatives, diuretics, diet pills, or vomiting (21.3%) were also reported. Coaches and trainers often encouraged athletes to cut weight before competition. The methods recommended are potentially harmful with severe health risks, including compromised nutritional status and diminished athletic performance. This is of particular concern in young athletes who are still growing and developing physically. Enhancing knowledge and awareness for coaches, athletes, and parents regarding potential dangers, along with improved nutrition education, is critical for reducing the magnitude and misuse of rapid weight loss methods.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Artes Marciais , Mentores , Redução de Peso , Adulto , Atletas , Peso Corporal , Desidratação , Dieta , Jejum , Feminino , Humanos , Masculino , Adulto Jovem
18.
Prev Med ; 108: 47-52, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29277416

RESUMO

Evidence about the health effects of weight cycling is not consistent, with some studies suggesting it is harmful for health. Here we investigated whether weight cycling was associated with weight change and mental health outcomes in 10,428 participants in the mid-age cohort of The Australian Longitudinal Study of Women's Health (ALSWH) over 12years. In 1998 the women were asked how many times they had ever intentionally lost at least 5kg and how many times had they regained this amount. Women were categorised into four weight pattern groups: frequent weight cyclers (FWC, three or more weight cycles), low frequency weight cyclers (LFWC, one or two weight cycles), non-weight cyclers (NWC), and weight loss only (WL). We used generalised linear modelling to investigate relationships between weight pattern group, weight change and mental health outcomes. In 1998, 15% of the women were FWC, 24% LFWC, 46% NWC and 15% were WL. Weight change was similar across weight pattern groups in women with obesity, however healthy weight and overweight FWC gained more weight than women who did not weight cycle. We found no difference in overall mental health scores between groups, but both LFWC and FWC had higher odds of depressive symptoms (adjusted OR 1.5, 95%CI: 1.1 to 1.9 and 1.7, 95%CI: 1.1 to 2.4, respectively) than NWC. Our results suggest that, although weight cycling is not associated with greater weight gain in women with obesity, it may increase depressive symptoms.


Assuntos
Dieta Redutora/métodos , Nível de Saúde , Aumento de Peso/fisiologia , Redução de Peso/fisiologia , Austrália , Índice de Massa Corporal , Feminino , Humanos , Estudos Longitudinais , Saúde Mental , Pessoa de Meia-Idade , Obesidade/psicologia , Estudos Prospectivos , Fatores de Risco
19.
Scand J Public Health ; 45(3): 305-313, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28443486

RESUMO

AIMS: This study aimed to investigate whether repeated lifestyle interventions lead to progressive weight loss or to weight cycling. METHODS: A retrospective review chart study with follow-up on 2120 participants (mean±SD age 36±15 years; body weight 116±28 kg; fat 43±6%). All had participated in one to four 11-12 week lifestyle interventions (residential weight loss programme, mixed activities). Weight loss was promoted through a hypocaloric diet (-500 to -700 kcal/day) and daily physical activity (1-3 hours/day). Primary outcomes were weight loss and change in body composition (bioimpedance measurements) after the intervention periods and at follow-up. RESULTS: A total of 2120, 526, 139 and 47 people participated in one to four interventions with mean±SEM times from start to follow-up of 1.3±0.1, 2.9±0.2, 4.2±0.3 and 5.2±0.4 years respectively. Overall 50, 41, 18 and 11% of the participants were lost to follow-up after one to four interventions, respectively. The cumulated weight loss at follow-up increased with the number of interventions from one to four: 12.2±0.1, 15.9±0.7, 16.1±1.2 and 18.5±2.0 kg ( p<0.001). The ratios between cumulated loss of fat and fat free mass after one to four interventions decreased with the number of interventions (2.4, 2.2, 2.1 and 1.4). Rates of weight loss during the interventions ranged from 0.70±0.06 to 1.06±0.01 kg/week and the maximum weight regain during the follow-up periods was 0.039±0.007 kg/week. CONCLUSIONS: Repeated relatively short lifestyle interventions in a selected and motivated group can be an efficient method for weight loss maintenance with only limited body weight cycling in the interim periods. However, the relationship between loss of fat and fat free mass might change in an unfavourable direction.


Assuntos
Estilo de Vida , Obesidade/terapia , Redução de Peso , Programas de Redução de Peso/métodos , Adulto , Composição Corporal , Dinamarca , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
20.
Biochem Biophys Res Commun ; 478(3): 1310-6, 2016 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-27562717

RESUMO

Dieting often leads to body weight cycling involving repeated weight loss and regain. However, little information is available regarding rapid-response serum markers of overnutrition that predict body weight alterations during weight cycling. Here, we report the rapid response of serum leukocyte cell-derived chemotaxin 2 (LECT2), a hepatokine that induces insulin resistance in skeletal muscle, during diet-induced weight cycling in mice. A switch from a high-fat diet (HFD) to a regular diet (RD) in obese mice gradually decreased body weight but rapidly decreased serum LECT2 levels within 10 days. In contrast, a switch from a RD to a HFD rapidly elevated serum LECT2 levels. Serum LECT2 levels showed a positive correlation with liver triglyceride contents but not with adipose tissue weight. This study demonstrates the rapid response of LECT2 preceding body weight alterations during weight cycling in mice and suggests that measurement of serum LECT2 may be clinically useful in the management of obesity.


Assuntos
Peso Corporal , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Tecido Adiposo/patologia , Adiposidade , Animais , Biomarcadores/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Insulina/sangue , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Tamanho do Órgão , Hipernutrição/sangue , Hipernutrição/patologia
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