Margarita D. Tsiros

Health-related quality of life in obese children and adolescents

Objective:This review addresses the effect of overweight and obese weight status on pediatric health-related quality of life (HRQOL).Method:Web of Science, Medline, CINAHL, Cochrane Library, EMBASE, AMED and PubMed were searched for peer-reviewed studies in English reporting HRQOL and weight status in youth (<21 years), published before March 2008.Results:Twenty-eight articles were identified. Regression of HRQOL against body mass index (BMI) using pooled data from 13 studies utilizing the Pediatric Quality of Life Inventory identified an inverse relationship between BMI and pediatric HRQOL (r=−0.7, P=0.008), with impairments in physical and social functioning consistently reported. HRQOL seemed to improve with weight loss, but randomized controlled trials were few and lacked long-term follow-up.Conclusions:Little is known about the factors associated with reduced HRQOL among overweight or obese youth, although gender, age and obesity-related co-morbidities may play a role. Few studies have examined the differences in HRQOL between community and treatment-seeking samples. Pooled regressions suggest pediatric self-reported HRQOL can be predicted from parent proxy reports, although parents of obese youths tend to perceive worse HRQOL than children do about themselves. Thus, future research should include both pediatric and parent proxy perspectives.

Treatment of adolescent overweight and obesity

Adolescence is a vulnerable period for the development of obesity, and adolescent weight tracks strongly into adulthood. Previous reviews of treatment strategies have failed to discriminate between adolescents and children, thereby, disregarding the uniqueness of this population. Hence, this review aims to summarise the evidence for treatment approaches for adolescent obesity. Pubmed, OVID, EBSCOhost and Google Scholar were searched for randomised controlled trials, meta-analyses and systematic reviews testing treatments for overweight/obese adolescents (aged 12–19 years), published from 1982–2006 in English. Eligible studies had to assess either weight, percentage overweight, body mass index (BMI) or body fat. Thirty-four randomised controlled trials were eligible. The results of this review indicate that the safety and efficacy of surgical and pharmacotherapy treatments for adolescent obesity is uncertain. Diet and physical activity approaches may improve obese status in the short term. However, obesity interventions appear more effective when strategies are combined, rather than when used in isolation. Psychological interventions, such as behavioural and cognitive behavioural therapy, show promise in achieving the necessary lifestyle changes for obesity reduction; however, long-term follow-up studies are needed. There were multiple limitations in appraising the literature. Inconsistent definitions of overweight/obesity make comparisons between studies difficult. Many studies have not used direct adiposity measures, have failed to assess pubertal status or have not used an exclusive adolescent sample. We conclude that, despite these limitations, current evidence indicates that behavioural and cognitive behavioural strategies combined with diet and physical activity approaches may assist in reducing adolescent obesity,although long-term follow-up studies are needed.

Objectively measured sedentary behaviour and health and development in children and adolescents: systematic review and meta‐analysis

Sedentary behaviour has emerged as a unique determinant of health in adults. Studies in children and adolescents have been less consistent. We reviewed the evidence to determine if the total volume and patterns (i.e. breaks and bouts) of objectively measured sedentary behaviour were associated with adverse health outcomes in young people, independent of moderate‐intensity to vigorous‐intensity physical activity. Four electronic databases (EMBASE MEDLINE, Ovid EMBASE, PubMed and Scopus) were searched (up to 12 November 2015) to retrieve studies among 2‐ to 18‐year‐olds, which used cross‐sectional, longitudinal or experimental designs, and examined associations with health outcomes (adiposity, cardio‐metabolic, fitness, respiratory, bone/musculoskeletal, psychosocial, cognition/academic achievement, gross motor development and other outcomes). Based on 88 eligible observational studies, level of evidence grading and quantitative meta‐analyses indicated that there is limited available evidence that the total volume or patterns of sedentary behaviour are associated with health in children and adolescents when accounting for moderate‐intensity to vigorous‐intensity physical activity or focusing on studies with low risk of bias. Quality evidence from studies with robust designs and methods, objective measures of sitting, examining associations for various health outcomes, is needed to better understand if the overall volume or patterns of sedentary behaviour are independent determinants of health in children and adolescents.

Obesity: the new childhood disability?

This review addresses the impact of obesity on paediatric physical functioning utilizing the World Health Organization International Classification of Functioning, Disability and Health Framework (ICF). The ICF encompasses functioning (as it relates to all body functions and structures), activities (undertaking a particular task) and participation (in a life situation) with disability referring to impairments in body functions/structures, activity restrictions or participation limitations. Electronic databases were searched for peer‐reviewed studies published in English prior to May 2009 that examined aspects of physical functioning in children (≤18 years). Eligible studies (N = 104) were ranked by design and synthesized descriptively. Childhood obesity was found to be associated with deficits in function, including impaired cardiorespiratory fitness and performance of motor tasks; and there was some limited evidence of increased musculoskeletal pain and decrements in muscle strength, gait and balance. Health‐related quality of life and the subset of physical functioning was inversely related to weight status. However, studies investigating impacts of obesity on wider activity and participation were lacking. Further research utilizing the ICF is required to identify and better characterize the effects of paediatric obesity on physical function, activity and participation, thereby improving targets for intervention to reduce disability in this population.

Day-to-day physical functioning and disability in obese 10- to 13-year-olds

What is already known about this subject? Compared with their healthy‐weight peers, children with obesity have; impaired physical health‐related quality of life reduced physical activity levels reduced capacity to perform certain weight‐bearing tasks in field‐based fitness tests

The long-term effect of minimalist shoes on running performance and injury: design of a randomised controlled trial.

Introduction The outcome of the effects of transitioning to minimalist running shoes is a topic of interest for runners and scientists. However, few studies have investigated the longer term effects of running in minimalist shoes. The purpose of this randomised controlled trial (RCT) is to investigate the effects of a 26 week transition to minimalist shoes on running performance and injury risk in trained runners unaccustomed to minimalist footwear. Methods and analysis A randomised parallel intervention design will be used. Seventy-six trained male runners will be recruited. To be eligible, runners must be aged 18–40 years, run with a habitual rearfoot footfall pattern, train with conventional shoes and have no prior experience with minimalist shoes. Runners will complete a standardised transition to either minimalist or control shoes and undergo assessments at baseline, 6 and 26 weeks. 5 km time-trial performance (5TT), running economy, running biomechanics, triceps surae muscle strength and lower limb bone mineral density will be assessed at each time point. Pain and injury will be recorded weekly. Training will be standardised during the first 6 weeks. Primary statistical analysis will compare 5TT between shoe groups at the 6-week time point and injury incidence across the entire 26-week study period. Ethics and dissemination This RCT has been approved by the Human Research Ethics Committee of the University of South Australia. Participants will be required to provide their written informed consent prior to participation in the study. Study findings will be disseminated in the form of journal publications and conference presentations after completion of planned data analysis. Trial registration number This RCT has been registered with the Australian New Zealand Clinical Trials Registry (ACTRN12613000642785).

Musculoskeletal pain in obese compared with healthy-weight children.

Objectives:To investigate whether obesity is associated with musculoskeletal pain in children. Materials and Methods:Obese (n=107) and healthy-weight (n=132) 10- to 13-year-old children (132 males, 107 females) participated in an observational case-control study. Children self-reported pain location (excluding abdominal pain), pain intensity (current and prior week), and pain prevalence (overall and lower limb) using the Pediatric Pain Questionnaire. Body composition was assessed (dual-energy x-ray absorptiometry) and children wore an accelerometer for 8 days. Results:After adjustment for accelerometry (weekly average counts per hour) and socioeconomic status, obese children had more intense pain (worst pain, P=0.006), pain in more locations (P⩽0.005), and a higher prevalence of lower limb pain (60% vs. 52% respectively, P=0.012) than healthy-weight children. Significant relationships were observed between body mass index and total pain locations (P⩽0.004, unadjusted and adjusted) and worst pain intensity (P⩽0.009, adjusted for socioeconomic status/accelerometry). There were no significant relationships between percent body fat and pain variables (unadjusted/adjusted analyses, P=0.262 to 1.0). Discussion:Obesity in children was associated with increased overall and lower limb musculoskeletal pain, for which body mass index was a stronger predictor than adiposity. Clinicians treating obese children should screen for pain and prescribe exercise programs that take their symptoms into account.

Redistribution of Mechanical Work at the Knee and Ankle Joints During Fast Running in Minimalist Shoes

CONTEXT Minimalist shoes have been suggested as a way to alter running biomechanics to improve running performance and reduce injuries. However, to date, researchers have only considered the effect of minimalist shoes at slow running speeds. OBJECTIVE To determine if runners change foot-strike pattern and alter the distribution of mechanical work at the knee and ankle joints when running at a fast speed in minimalist shoes compared with conventional running shoes. DESIGN Crossover study. SETTING Research laboratory. PATIENTS OR OTHER PARTICIPANTS Twenty-six trained runners (age = 30.0 ± 7.9 years [age range, 18-40 years], height = 1.79 ± 0.06 m, mass = 75.3 ± 8.2 kg, weekly training distance = 27 ± 15 km) who ran with a habitual rearfoot foot-strike pattern and had no experience running in minimalist shoes. INTERVENTION(S) Participants completed overground running trials at 18 km/h in minimalist and conventional shoes. MAIN OUTCOME MEASURE(S) Sagittal-plane kinematics and joint work at the knee and ankle joints were computed using 3-dimensional kinematic and ground reaction force data. Foot-strike pattern was classified as rearfoot, midfoot, or forefoot strike based on strike index and ankle angle at initial contact. RESULTS We observed no difference in foot-strike classification between shoes (χ21 = 2.29, P = .13). Ankle angle at initial contact was less (2.46° versus 7.43°; t25 = 3.34, P = .003) and strike index was greater (35.97% versus 29.04%; t25 = 2.38, P = .03) when running in minimalist shoes compared with conventional shoes. We observed greater negative (52.87 J versus 42.46 J; t24 = 2.29, P = .03) and positive work (68.91 J versus 59.08 J; t24 = 2.65, P = .01) at the ankle but less negative (59.01 J versus 67.02 J; t24 = 2.25, P = .03) and positive work (40.37 J versus 47.09 J; t24 = 2.11, P = .046) at the knee with minimalist shoes compared with conventional shoes. CONCLUSIONS Running in minimalist shoes at a fast speed caused a redistribution of work from the knee to the ankle joint. This finding suggests that runners changing from conventional to minimalist shoes for short-distance races could be at an increased risk of ankle and calf injuries but a reduced risk of knee injuries.

Effects of a minimalist shoe on running economy and 5-km running performance

ABSTRACT The purpose of this study was to determine if minimalist shoes improve time trial performance of trained distance runners and if changes in running economy, shoe mass, stride length, stride rate and footfall pattern were related to any difference in performance. Twenty-six trained runners performed three 6-min sub-maximal treadmill runs at 11, 13 and 15 km·h−1 in minimalist and conventional shoes while running economy, stride length, stride rate and footfall pattern were assessed. They then performed a 5-km time trial. In the minimalist shoe, runners completed the trial in less time (effect size 0.20 ± 0.12), were more economical during sub-maximal running (effect size 0.33 ± 0.14) and decreased stride length (effect size 0.22 ± 0.10) and increased stride rate (effect size 0.22 ± 0.11). All but one runner ran with a rearfoot footfall in the minimalist shoe. Improvements in time trial performance were associated with improvements in running economy at 15 km·h−1 (r = 0.58), with 79% of the improved economy accounted for by reduced shoe mass (P < 0.05). The results suggest that running in minimalist shoes improves running economy and 5-km running performance.

The Biodex Isokinetic Dynamometer for knee strength assessment in children: Advantages and limitations

OBJECTIVE To critically appraise the Biodex System 4 isokinetic dynamometer for strength assessment of children. METHODS Appraisal was based on experiences from two independent laboratories involving testing of 213 children. Issues were recorded and the manufacturer was consulted regarding appropriate solutions. RESULTS The dynamometer had insufficient height adjustment for alignment of the knee for some children, requiring the construction of padding to better fit the child within the dynamometer. Potential for entrapment of the non-testing leg was evident in the passive and eccentric modes and a leg bracket restraint was constructed. Automated gravity correction did not operate when protocols were linked or data was exported to an external device. CONCLUSIONS Limitations were noted, some of which were applicable to knee strength testing in general and others which were specific to use with children. However, most of these obstacles could be overcome, making the Biodex System 4 suitable for assessment of knee strength in children.