Health Benefits of Long-Term Weight-Loss Maintenance.

Obesity is a chronic and complex medical condition associated with a large number of complications affecting most organs and systems through multiple pathways. Strategies for weight management include behavioral, pharmacological, and surgical interventions, all of which can result in a reduction in obesity-related comorbidities and improvements in quality of life. However, subsequent weight regain often reduces the durability of these improvements. The objective of this article is to review evidence supporting the long-term effects of intentional weight loss on morbidity, mortality, quality of life, and health-care cost. Overall, considerable evidence suggests that intentional weight loss is associated with clinically relevant benefits for the majority of obesity-related comorbidities. However, the degree of weight loss that must be achieved and sustained to reap these benefits varies widely between comorbidities.

Delayed bedtime due to screen time in schoolchildren: importance of area deprivation.

BACKGROUND: Sleep duration is an important predictor of obesity and health. This study evaluated the association between late bedtime and screen time, and the role of geographical deprivation in English schoolchildren. METHODS: We collected bedtime and waking time, screen time, sociodemographic data and measured body mass index in a cross-section of 1332 11-15-year-old schoolchildren (45.7% female) participating in the East of England healthy heart study. Logistic regression was used to determine the likelihood of late bedtime in schoolchildren with different screen time and from a different geographic location. Mean differences were assessed either on ANOVA or t-test. RESULTS: Approximately 42% of boys went to bed late at night compared with 37% of girls. When compared to those with <2 h of daily screen time, schoolchildren with 2-4 h of screen time were more likely [odds ratio (OR) = 1.50, 95% confidence interval (CI): 1.07-2.09] to go to bed late at night while those with >4 h of daily screen time were most likely to go to sleep late at night (OR, 1.97; 95%CI: 1.34-2.89). Late bedtime was associated with deprivation in schoolchildren. CONCLUSIONS: High screen time and deprivation may explain lateness in bedtime in English schoolchildren. This explanation may vary according to area deprivation and geographic location. Family-centered interventions and parental support are important to reduce screen time, late bedtime and increase sleep duration.

Association between habitual school travel and muscular fitness in youth.

OBJECTIVE: To determine whether active school travel is associated with muscular fitness, which is an emerging marker of youth health. METHODS: Handgrip strength, vertical jump and vertical jump peak power were measured in n=6829 English schoolchildren (53% males, age 12.9 ± 1.2 years) between 2007 and 2011. Participants were grouped according to self-reported habitual school travel modality. RESULTS: Cyclists had greater handgrip strength than passive travelers. Vertical jump height was greater in walkers and cyclists compared with passive travelers. Jump peak power was also higher in walkers than in the passive travel group. Compared with passive travelers, cyclists had a higher (age, sex and BMI-adjusted) likelihood of good handgrip strength (OR 1.42, 95%CI;1.14-1.76) and walkers were more likely to have good measures for vertical jump peak power (OR 1.14, 95%CI;1.00-1.29). Cyclists' likelihood of having good handgrip strength remained significantly higher when adjusted for physical activity (OR 1.29, 95%CI;1.08-1.46). CONCLUSION: Muscular fitness differs according to school travel habits. Cycling is independently associated with better handgrip strength perhaps due to the physical demands of the activity. Better muscular fitness may provide another health-related reason to encourage active school travel.

Independence of physical activity and screen time as predictors of cardiorespiratory fitness in youth.

BACKGROUND: Screen time (ST) is associated with physical activity (PA) levels. We aimed to investigate the relationship between ST and fitness. METHODS: We assessed fitness and daily ST in 7,466 10-16-y-old schoolchildren from the east of England. The differences in fitness between ST groups, and the association between ST and fitness were assessed. RESULTS: ST was negatively associated with fitness in boys of all ages (P < 0.001) and girls in grades 6-9 (P < 0.005). Boys were less likely to be fit if they reported >2 h/d ST (odds ratio (OR): 0.70, 95% confidence interval (CI): 0.58-0.85) or >4 h/d (OR: 0.45, 95% CI: 0.35-0.57) ST, as were girls reporting >4 h/d ST (OR: 0.58, 95% CI: 0.43-0.78). Controlling for PA levels attenuated these odds in boys reporting >2 h/d ST (OR: 0.81, 95% CI: 0.66-0.91) or >4 h/d ST (OR: 0.65, 95% CI: 0.50-0.84) and in girls reporting >4 h/d ST (OR: 0.68, 95% CI: 0.50-0.93). CONCLUSION: These first data from English children show a negative association between ST and fitness in youth. Of note, very high levels of daily ST (>4 h) are associated with poor fitness. Some of the associations were mediated by PA levels. Our data support international recommendations to limit ST to <2 h/d; we believe such guidance should be issued in the United Kingdom.

Prevalence of elevated mean arterial pressure and how fitness moderates its association with BMI in youth.

OBJECTIVE: Cardiorespiratory fitness is known to be cardioprotective and its association with the components of the metabolic syndrome in children is becoming clearer. The aim of the present study was to examine the extent to which cardiorespiratory fitness may offset the weight-related association with mean arterial pressure (MAP) in schoolchildren. DESIGN: Cross-sectional study. SETTINGS: Schoolchildren from the East of England, U.K. SUBJECTS: A total of 5983 (48% females) schoolchildren, 10 to 16 years of age, had height, weight and blood pressure measured by standard procedures and cardiorespiratory fitness assessed by the 20 m shuttle-run test. Participants were classified as fit or unfit using internationally accepted fitness cut-off points; and as normal weight, overweight or obese based on BMI, again using international cut-off points. Age-adjusted ANCOVA was used to determine the main effects and interaction of fitness and BMI on MAP Z-score. Logistic regression models were used to estimate odds ratios of elevated MAP. RESULTS: Prevalence of elevated MAP in schoolchildren was 14.8% overall and 35.7% in those who were obese-unfit. Approximately 21% of participants were overweight and 5% obese, while 23% were classified as unfit. MAP generally increased across BMI categories and was higher in the aerobically unfit participants. Obese-fit males had lower MAP compared with obese-unfit males (P < 0.001); this trend was similar in females (P = 0.05). CONCLUSIONS: Increasing fitness level may have a positive impact on the weight-related elevations of MAP seen in obese and overweight schoolchildren.

Physical Activity Questionnaire for children and adolescents: English norms and cut-off points.

BACKGROUND: The Physical Activity Questionnaire for Children and Adolescents (PAQ-C/-A) provides general estimates of physical activity levels. Following recent expert recommendations for using the PAQ for population surveillance, the aim of this paper was twofold: first, to describe normative PAQ data for English youth; and second, to determine a criterion-referenced PAQ-score cut-off point. METHODS: Participants (n = 7226, 53% boys, 10-15 years) completed an anglicized version of the PAQ. Peak oxygen uptake (VO2peak ) was predicted from PACER lap count according to latest FITNESSGRAM standards and categorized into "at-risk" and "no-risk" for metabolic syndrome. ROC curves were drawn for each age-sex group to identify PAQ scores, which categorized youth into "sufficiently active" versus "low-active" groups, using cardiorespiratory fitness as the criterion-referenced standard. RESULTS: PAQ scores were higher in boys than in girls and declined with age. Mean PAQ score was a significant, albeit relatively weak (area under the curve < 0.7) discriminator between "at-risk" and "no-risk." PAQ scores of ≥2.9 for boys and ≥2.7 for girls were identified as cut-off points, although it may be more appropriate to use lower, age-specific PAQ scores for girls of 13, 14 and 15 years (2.6, 2.4, 2.3, respectively). CONCLUSION: The normative and criterion-referenced PAQ values may be used to standardize and categorize PAQ scores in future youth population studies.

Quantification of the relative age effect in three indices of physical performance.

The relative age effect (RAE) describes the relationship between an individual's birth month and their level of attainment in sports. There is a clustering of birth dates just after the cutoff used for selection in age-grouped sports, and it is hypothesized that such relatively older sportspeople may enjoy maturational and physical advantages over their younger peers. There is, however, little empirical evidence of any such advantage. This study investigated whether schoolchildren's physical performance differed according to which quarter of the school year they were born in. Mass, stature, body mass index, cardiorespiratory fitness, strength, and power were measured in 10 to 16 year olds (n = 8,550, 53% male). We expressed test performance as age- and sex-specific z-scores based on reference data with age rounded down to the nearest whole year and also as units normalized for body mass. We then compared these values between yearly birth quarters. There were no significant main effects for differences in anthropometric measures in either sex. Girls born in the first quarter of the school year were significantly stronger than those born at other times when handgrip was expressed as a z-score. As z-scores, all measures were significantly higher in boys born in either the first or second yearly quarters. Relative to body mass, cardiorespiratory fitness was higher in boys born in the first quarter and power was higher in those born in the second quarter. The RAE does not appear to significantly affect girls' performance test scores when they are expressed as z-score or relative to body mass. Boys born in the first and second quarters of the year had a significant physical advantage over their relatively younger peers. These findings have practical bearing if coaches use fitness tests for talent identification and team selection. Categorizing test performance based on rounded down values of whole-year age may disadvantage children born later in the selection year. These relatively younger children may be less to gain selection for teams or training programmes.

Screen time and passive school travel as independent predictors of cardiorespiratory fitness in youth.

OBJECTIVE: The most prevalent sedentary behaviours in children and adolescents are engagement with small screen media (screen-time) and passive travel (by motorised vehicle). The objective of this research was to assess the independence of these behaviours from one another and from physical activity as predictors of cardiorespiratory fitness in youth. METHODS: We measured cardiorespiratory fitness in n=6819 10-16 year olds (53% male) who self-reported their physical activity (7-day recall) school travel and screen time habits. Travel was classified as active (walking, cycling) or passive; screen time as <2 h, 2-4 h or >4 h. RESULTS: The multivariate odds of being fit were higher in active travel (Boys: OR 1.32, 95% CI: 1.09-1.59; Girls: OR 1.46, 1.15-1.84) than in passive travel groups. Boys reporting low screen time were more likely to be fit than those reporting >4 h (OR 2.11, 95% CI: 1.68-2.63) as were girls (OR 1.66, 95% CI: 1.24-2.20). These odds remained significant after additionally controlling for physical activity. CONCLUSION: Passive travel and high screen time are independently associated with poor cardiorespiratory fitness in youth, and this relationship is independent of physical activity levels. A lifestyle involving high screen time and habitual passive school travel appears incompatible with healthful levels of cardiorespiratory fitness in youth.

Changing provider behaviour to increase nurse visits for obesity in family practice: the 5As Team randomized controlled trial.

BACKGROUND: There is increasing recognition that health care professionals often fail to provide meaningful obesity care in routine clinical practice. There is scant information on how to support practice change. The objective of the 5AsT trial was to assess whether a co-created educational intervention would increase the quantity of obesity visits conducted by family practice nurses. METHODS: We conducted a randomized controlled trial with convergent mixed-methods evaluation in a primary care network in Alberta, Canada. The intervention, based on the Theoretical Domains Framework and 5As of Obesity Management, included 12 2-hour interactive educational sessions from November 2013 to April 2014. Twenty-four teams of nurses, mental health workers and dietitians were randomly assigned to receive the intervention or regular training. The primary outcome measure was the rate ratio of nurse visits for adult obesity care to total clinical visits. Qualitative thematic analysis was previously used to identify barriers and facilitators to intervention uptake. In this study, mixed-methods analysis assessed the impact of these factors on individual nurses' outcomes. RESULTS: There was no significant increase in visits over the 6-month intervention (rate ratio 1.30, 95% confidence interval [CI] 0.83-2.03) nor the 9-month post-intervention period (rate ratio 1.38, 95% CI 0.87-2.19). However, provider confidence, views of obesity management, role identity and team and patient relationships were found to affect individual nurses' uptake of the intervention. INTERPRETATION: Although the intervention did not demonstrate a significant increase in nurse visits for obesity care, this study provides insights into health care practitioners' challenges in changing their approach to obesity management. To improve provider capacity to change effectively within their teams, interventions need to foster not only provider knowledge but also confidence. Trial registration: ClinicalTrials.gov, no. NCT01967797.

Impact of the 5As Team study on clinical practice in primary care obesity management: a qualitative study.

BACKGROUND: The 5As [Ask, Assess, Advise, Agree, Assist] of Obesity Management Team study was a randomized controlled trial of an intervention that was implemented and evaluated to help primary care providers improve clinical practice for obesity management. This paper presents health care provider perspectives of the impacts of the intervention on individual provider and team practices. METHODS: This study reports a thematic network analysis of qualitative data collected during the 5As Team study, which involved 24 chronic disease teams affiliated with family practices in a Primary Care Network in Alberta. Qualitative data from 28 primary care providers (registered nurses/nurse practitioners [n = 14], dietitians [n = 7] and mental health workers [n = 7]) in the intervention arm were collected through semistructured interviews, field notes, practice facilitator diaries and 2 evaluation workshop questionnaires. RESULTS: Providers internalized 5As Team intervention concepts, deepening self-evaluation and changing clinical reasoning around obesity. Providers perceived that this internalization changed the provider-patient relationship positively. The intervention changed relations between providers, increasing interdisciplinary understanding, collaboration and discovery of areas for improvement. This personal and interpersonal evolution effected change to the entire Primary Care Network. INTERPRETATION: The 5As Team intervention had multiple impacts on providers and teams to improve obesity management in primary care. Improved provider confidence and capability is a precondition of developing effective patient interventions. Trial registration: ClinicalTrials.gov, no.: NCT01967797.

Implementation and evaluation of the 5As framework of obesity management in primary care: design of the 5As Team (5AsT) randomized control trial.

BACKGROUND: Obesity is a pressing public health concern, which frequently presents in primary care. With the explosive obesity epidemic, there is an urgent need to maximize effective management in primary care. The 5As of Obesity Management™ (5As) are a collection of knowledge tools developed by the Canadian Obesity Network. Low rates of obesity management visits in primary care suggest provider behaviour may be an important variable. The goal of the present study is to increase frequency and quality of obesity management in primary care using the 5As Team (5AsT) intervention to change provider behaviour. METHODS/DESIGN: The 5AsT trial is a theoretically informed, pragmatic randomized controlled trial with mixed methods evaluation. Clinic-based multidisciplinary teams (RN/NP, mental health, dietitians) will be randomized to control or the 5AsT intervention group, to participate in biweekly learning collaborative sessions supported by internal and external practice facilitation. The learning collaborative content addresses provider-identified barriers to effective obesity management in primary care. Evidence-based shared decision making tools will be co-developed and iteratively tested by practitioners. Evaluation will be informed by the RE-AIM framework. The primary outcome measure, to which participants are blinded, is number of weight management visits/full-time equivalent (FTE) position. Patient-level outcomes will also be assessed, through a longitudinal cohort study of patients from randomized practices. Patient outcomes include clinical (e.g., body mass index [BMI], blood pressure), health-related quality of life (SF-12, EQ5D), and satisfaction with care. Qualitative data collected from providers and patients will be evaluated using thematic analysis to understand the context, implementation and effectiveness of the 5AsT program. DISCUSSION: The 5AsT trial will provide a wide range of insights into current practices, knowledge gaps and barriers that limit obesity management in primary practice. The use of existing resources, collaborative design, practice facilitation, and integrated feedback loops cultivate an applicable, adaptable and sustainable approach to increasing the quantity and quality of weight management visits in primary care. TRIAL REGISTRATION: NCT01967797.

Recreational cycling and cardiorespiratory fitness in English youth.

PURPOSE: Schoolchildren who cycle to school have higher cardiorespiratory fitness (CRF) than those who are driven or use public transport. The purpose of this study was to determine whether recreational cycling is similarly associated with CRF. METHODS: Participants were 5578 (54% males) English schoolchildren (10.0-15.9 yr). All reported frequency of recreational cycling events via 7-d recall. Responses were categorized as follows: "noncyclists" = 0, "occasional cyclists" = 1-4, or "regular cyclists" = 5+ (times per week). CRF was assessed using the 20-m shuttle run test with performance classified as "fit" or "unfit" based on FITNESSGRAM standards. RESULTS: Overall, 26% of males and 46% of females were noncyclists. Compared with noncyclists, the 40% of males and 42% of females classified as occasional cyclists were more likely to be fit (males: odds ratio (OR) = 1.30, 95% confidence interval (CI) = 1.07-1.59; females: OR = 1.41, 95% CI = 1.13-1.76). Regular cyclists (34% males and 12% females) had a greater likelihood still of being classified as fit (males: OR = 1.58, 95% CI = 1.29-1.95; females: OR = 1.55, 95% CI = 1.09-2.20). No odds remained significant after adjusting for physical activity. Removal of participants who cycled to school had little overall effect on the likelihood of being classified as being fit. CONCLUSIONS: Previous research has focused only on young people's commuter cycling habits, at the expense of the more common activity of recreational cycling. Recreational cycling may provide an alternative target for interventions to increase physical activity and improve CRF youth. Recreational cycling could potentially serve as a way to gain cycling confidence and establish habits that act as precursors to commuter cycling.