Paediatric obesity, physical activity and the musculoskeletal system

The path less traveled: Using structural equation modeling to investigate factors influencing bone functional morphology

OBJECTIVES

The relationship between an organism's mechanical environment and its bone strength has been long established by experimental research. Multiple intrinsic and extrinsic factors, including body mass, muscle strength, genetic background, and nutritional and/or hormonal status, are likely to influence bone deposition and resorption throughout the lifespan, complicating this relationship. Structural equation modeling (SEM) is uniquely positioned to parse this complex set of influences.

MATERIALS AND METHODS

Data from the Third National Health and Nutrition Examination Survey, including sex, total body mass, lean body mass, exercise frequency, peak body mass, and age, were analyzed using SEM to determine how they affect bone strength both individually and combined.

RESULTS

Body mass is typically the driver of cross-sectional area, but body mass and lean mass have similar effects on the polar moment of area (J). Peak body mass had a strong direct effect on J, despite decreasing strongly with increases in lean mass. Exercise also did not confer a large direct effect on cross-sectional area or J but did modify body mass and lean mass. In females, intentional weight loss was associated with decreased exercise levels.

DISCUSSION

SEM is a useful tool for parsing complex systems in bone functional morphology and has the potential to uncover causal links in the study of skeletal remodeling, including factors like weight loss or exercise that may have secondary effects.

A cross-sectional study of medial longitudinal arch development in children with different BMI

Introduction

The influence of excess weight on the development of children's feet remains a subject of debate. To further elucidate whether this relation occurs, this study compared arch morphology and flexibility in three groups of children: underweight, normal, and overweight.

Methods

In total, 1,532 children (807 boys, 725 girls; age range 7-11 years) participated in the study. The researchers measured the participants' height and weight, calculated their body mass index, and categorized their weight status as underweight, normal weight, or overweight. A three-dimensional foot model was taken using a three-dimensional plantar scanner under non-weight-bearing and weight-bearing conditions to obtain arch morphometric indices (arch index and arch volume) and arch flexibility index (arch volume index).

Results

Analysis of the data showed that the arch index was higher in overweight children compared to underweight and normal weight children (p < 0.05), but the differences in arch volume and arch volume index in overweight children compared to underweight and normal weight children were not statistically significant (p > 0.05). All children were divided into flatfoot, normal, and pes cavus groups according to arch index, and the arch volume index was statistically significant (p < 0.01).

Conclusions

Overweight was not absolutely associated with arch structure and arch flexibility in children from a three-dimensional perspective. Arch development is a long-term process, and it is not clear whether being overweight has an effect on soft tissue or bone formation. Future studies will focus on the effects of long-term overweight on foot structure and arch flexibility in children.

Childhood obesity and its impact on the characteristics of gait stance phases: a cross-sectional study

This study aimed to investigate the variations in foot type, laxity, dynamic characteristics of gait, and the characteristics of the stance phase of gait, in relation to body mass index (BMI) and groups of children of different ages. Additionally, it aimed to explore the correlations between BMI and these variables across children groups of different ages. A cross-sectional study was conducted involving 196 infants aged between 5 and 10 years old. The variables assessed included BMI, foot type, laxity, dynamic variables, and characteristics of the stance phase of gait. Significant variations were observed in foot type, laxity, certain dynamic variables, and characteristics of the stance phase of gait between normoweight (NW) and overweight/obese (OW/OB) groups among children aged between 5 and 10 years old (p ranged between 0.019 and 0.050). Moreover, BMI was also positively associated with the initial forefoot contact, heel off, total duration of the step, and forefoot contact phase of children 7 to 10 years of age (p ranged between < 0.010 and 0.040).   Conclusion: Children who are OW/OB had alterations at different stages of gait. Being OW/OB is related to alterations of the phases of gait mainly from 7 to 10 years of age, and spending more time in each of the phases of walking. This could indicate that children who are OW/OB, in addition to walking slower, overload the musculoskeletal system, subjecting their joints and muscles to greater stress. What is Known: • Children who are overweight (OW) and obese (OB) can experience changes in their musculoskeletal systems, posture, and gait due to increased body mass index. • OW and OB children experience additional stress on their musculoskeletal systems, impacting posture, biomechanics, mobility, physical activity, and daily tasks. Excessive plantar loading is linked to foot pain in adults. What is New: • Body mass index was positively associated with initial forefoot contact, heel off, total duration of the step, and forefoot contact phase in children aged 7 to 10 years old. OW/OB children aged 5-6 exhibited less ankle dorsiflexion and smaller relaxed calcaneal stance position (RCSP) as compared to normal-weight children. • Obese children aged 5-6 showed less pronation excursion, suggesting altered frontal plane movement due to RCSP differences. Children aged 7-8 who are OW/OB spent more time in certain gait phases, particularly in the forefoot contact phase. Being OW/OB is linked to altered gait parameters such as initial forefoot, heel off, total step duration, and forefoot contact phase. Being OW/OB was associated with a longer forefoot contact phase, particularly in the right foot.

Obese adolescents have higher risk for severe lower extremity fractures after falling

INTRODUCTION

Reports vary on the impact of obesity on the incidence of lower extremity fractures after a fall. We hypothesized that obese adolescents (OA) presenting after a fall have a higher risk of any and severe lower extremity fractures compared to non-OAs.

METHODS

A national database was queried for adolescents (12-17 years old) after a fall. Primary outcome included lower extremity fracture. Adolescents with a body mass index (BMI) ≥ 30 (OA) were compared to adolescents with a BMI < 30 (non-OA).

RESULTS

From 20,264 falls, 2523 (12.5%) included OAs. Compared to non-OAs, the rate of any lower extremity fracture was higher for OAs (51.5% vs. 30.7%, p < 0.001). This remained true for lower extremity fractures at all locations (all p < 0.05). After adjusting for sex and age, associated risk for any lower extremity fracture (OR 2.41, CI 2.22-2.63, p < 0.001) and severe lower extremity fracture (OR 1.31, CI 1.15-1.49, p < 0.001) was higher for OAs. This remained true in subset analyses of ground level falls (GLF) and falls from height (FFH) (all p < 0.05).

CONCLUSIONS

Obesity significantly impacts adolescents' risk of all types of lower extremity fractures after FFH or GLF. Hence, providers should have heightened awareness for possible lower extremity fractures in OAs.

LEVEL OF EVIDENCE

IV.

Initial study on an expert system for spine diseases screening using inertial measurement unit

In recent times, widely understood spine diseases have advanced to one of the most urgetn problems where quick diagnosis and treatment are needed. To diagnose its specifics (e.g. to decide whether this is a scoliosis or sagittal imbalance) and assess its extend, various kind of imaging diagnostic methods (such as X-Ray, CT, MRI scan or ST) are used. However, despite their common use, some may be regarded as (to a level) invasive methods and there are cases where there are contraindications to using them. Besides, which is even more of a problem, these are very expensive methods and whilst their use for pure diagnostic purposes is absolutely valid, then due to their cost, they cannot rather be considered as tools which would be equally valid for bad posture screening programs purposes. This paper provides an initial evaluation of the alternative approach to the spine diseases diagnostic/screening using inertial measurement unit and we propose policy-based computing as the core for the inference systems. Although the methodology presented herein is potentially applicable to a variety of spine diseases, in the nearest future we will focus specifically on sagittal imbalance detection.

Association between executive functions and gross motor skills in overweight/obese and eutrophic preschoolers: cross-sectional study

BACKGROUND

Preschool age (3-5 years old) is a crucial period for children to acquire gross motor skills and develop executive functions (EFs). However, the association between the qualitative gross motor skills and EFs remains unknown in preschoolers, especially among overweight and obese children.

METHODS

This was a cross-sectional, exploratory, and quantitative study carried out on 49 preschool children, divided into two subgroups according to their body mass index (overweight/obese: 24; eutrophic [normal weight]: 25). The mean age was 4.59 years. More than half of the sample were boys (55%) and most of the mothers had completed high school (67%) and were class C socioeconomic level (63%). Gross motor skills were assessed using the Test of Gross Motor Development-2, while EFs were evaluated using Semantic verbal fluency (SVF), Tower of Hanoi (TH), Day/Night Stroop, and Delayed Gratification tests. Multiple linear regression models adjusted for sex, age, maternal education, socioeconomic status, quality of the home environment, and quality of the school environment using the stepwise method were executed, considering the cognitive tasks as independent variables and gross motor skills as dependent variable.

RESULTS

The overweight/obese preschoolers showed worse locomotor skills than their eutrophic peers and below average gross motor quotient (GMQ). Overweight/obese girls performed worse in OC skills than boys with excess weight. SVF (number of errors) and TH (rule breaks) explained 57.8% of the variance in object control (OC) skills and 40.5% of the variance in GMQ (p < .05) in the overweight/obese children. Surprisingly, there was no significant association between any of the EF tasks and gross motor skills in the eutrophic children.

CONCLUSION

A relationship between EF tasks (number of errors in SVF and rule breaks in TH) and gross motor skills (OC and GMQ) was demonstrated in the overweight/obese preschoolers, indicating that worse cognitive flexibility, working memory, planning, and problem solving are associated with worse gross motor skills in this population when compared to eutrophic children.

Strength of association between body mass index and physical function scores in paediatric burn patients: A National Institute on Disability, Independent Living, and Rehabilitation Research Burn Model System study

OBJECTIVE

Increased body weight has been associated with reduced muscle wasting in the early catabolic phase after a severe burn. Yet, overweight and obese non-burn children often exhibit impaired musculoskeletal function, which may lead to poor physical function (PF). We aimed to determine the association between body mass index (BMI) at discharge and self-reported PF and caregiver proxy-reported PF during recovery of burned children.

MATERIALS AND METHODS

This is a retrospective multisite longitudinal study in paediatric burn patients ((8-17 y old at time of burn). PF outcome measures were self-reported mobility, proxy-reported mobility, and upper extremity PF evaluated using PROMIS measures at 6-, 12-, and 24-months after injury. Primary exposure variable was BMI-for-age at discharge.

RESULTS

A total of 118 paediatric patients, aged 11.7 ± 3.3 y, with burns covering 37.6 ± 18.8% of their total body surface area (TBSA) and BMI-for-age of 23.1 ± 5.4 kg/m² at discharge were analyzed. BMI at discharge was not significantly associated with self-reported mobility scores 6 months after burn (beta coefficient =-0.23, p = 0.31), had a positive effect on mobility at 12 months (beta = 0.46, p = 0.05), and no effect at 24 months after injury (beta=-0.10, p = 0.60), when adjusted for burn size. BMI did not have a significant effect on proxy-reported mobility or upper extremity PF.

CONCLUSION

A greater BMI at discharge was associated with improved self-reported PF at 12 months after burn but not at 6 months or 24 months, which suggests a faster recovery of PF in paediatric patients of larger body weight. Our data suggests that a larger body weight does not compromise the recovery of PF after burn.

Concurrent Training Promotes Greater Gains on Body Composition and Components of Physical Fitness Than Single-Mode Training (Endurance or Resistance) in Youth With Obesity

The prevalence of obesity in the pediatric population has become a major public health issue. Indeed, the dramatic increase of this epidemic causes multiple and harmful consequences, Physical activity, particularly physical exercise, remains to be the cornerstone of interventions against childhood obesity. Given the conflicting findings with reference to the relevant literature addressing the effects of exercise on adiposity and physical fitness outcomes in obese children and adolescents, the effect of duration-matched concurrent training (CT) [50% resistance (RT) and 50% high-intensity-interval-training (HIIT)] on body composition and physical fitness in obese youth remains to be elucidated. Thus, the purpose of this study was to examine the effects of 9-weeks of CT compared to RT or HIIT alone, on body composition and selected physical fitness components in healthy sedentary obese youth. Out of 73 participants, only 37; [14 males and 23 females; age 13.4 ± 0.9 years; body-mass-index (BMI): 31.2 ± 4.8 kg·m-2] were eligible and randomized into three groups: HIIT (n = 12): 3-4 sets×12 runs at 80-110% peak velocity, with 10-s passive recovery between bouts; RT (n = 12): 6 exercises; 3-4 sets × 10 repetition maximum (RM) and CT (n = 13): 50% serial completion of RT and HIIT. CT promoted significant greater gains compared to HIIT and RT on body composition (p < 0.01, d = large), 6-min-walking test distance (6 MWT-distance) and on 6 MWT-VO2max (p < 0.03, d = large). In addition, CT showed substantially greater improvements than HIIT in the medicine ball throw test (20.2 vs. 13.6%, p < 0.04, d = large). On the other hand, RT exhibited significantly greater gains in relative hand grip strength (p < 0.03, d = large) and CMJ (p < 0.01, d = large) than HIIT and CT. CT promoted greater benefits for fat, body mass loss and cardiorespiratory fitness than HIIT or RT modalities. This study provides important information for practitioners and therapists on the application of effective exercise regimes with obese youth to induce significant and beneficial body composition changes. The applied CT program and the respective programming parameters in terms of exercise intensity and volume can be used by practitioners as an effective exercise treatment to fight the pandemic overweight and obesity in youth.

The effects of adiposity, muscular strength, cardiorespiratory fitness, and fatigue on gait biomechanics in overweight and obese children

BACKGROUND

Obesity rates continue to increase in the child population. Muscular strength, cardiorespiratory fitness, and fatigue can potentially affect joint stresses in obese children. The purposes are to examine: (1) the relationship between cardiorespiratory fitness and the change in joint stress pre- to post-fatigue; (2) the predictive value of fitness, adiposity, and muscular strength on joint stresses in fatigued and non-fatigued states; and, (3) the relationships between % body fat from skinfold and air displacement plethysmography.

METHODS

Twenty-seven children, with body mass index above the 85th percentile for their age participated in this study. Lower limb joint moments were recorded before and after a fatiguing Progressive Aerobic Cardiovascular Endurance Run protocol. Linear regression was used to assess the relationship between (1) fitness and change in joint stress pre- to post-fatigue, and (2) measures of %body fat using skinfold and plethysmography. Furthermore, Bland-Altman analysis quantified the agreement between measured adiposity using the two methods.

FINDINGS

The strongest relationship was observed between fitness and the change in the knee extensor moment pre- to post-fatigue (R² = 0.24). Regardless of fatigue state, adiposity and strength were identified as the strongest predictors of joint moments. Skinfold estimates were moderately predictive (R² = 0.56) of %body fat from air displacement plethysmography, and these two measures demonstrated instrument agreement with no proportional bias.

INTERPRETATION

Fitness level is not related to changes in biomechanics pre- to post-fatigue in overweight and obese children. Adiposity and lower extremity strength most strongly influenced joint moments in the frontal and sagittal planes.

Association among length of residence, physical activity, and obesity in the US immigrants: A regression-based mediation analysis

OBJECTIVES

To examine the mediated relationship between objectively measured obesity, accelerometer-based moderate-to-vigorous physical activity (MVPA), and length of residence among US immigrants.

METHODS

A total of 885 adults (≥18 years) who were born outside the United States from the 2003 to 2006 National Health and Nutrition Examination Survey were included in the analysis. The participants were categorized into two groups (i.e., living in the United States ≥15 years vs. <15 years). MVPA time (minutes/day) was measured by ActiGraph accelerometry. Obesity was defined as body fat percentage measured by dual-energy X-ray absorptiometry. Regression-based mediation analysis was conducted using SURVEY procedures in SAS version 9.4.

RESULTS

When controlling for covariates, immigrants living in the United States for ≥15 years were significantly less likely to spend time participating in MVPA (c; β = -4.50, p = .04), and more likely to be at high risk of obesity (a; β = 1.70, p = .01) compared to those living in the United States for <15 years. Also, the relationship between obesity and MVPA was statistically significant (b; β = -0.80, p = .003). Length of residence was indirectly associated with MVPA (ab; β = -1.37, p = .03), suggesting that obesity mediated the association of length of residence on MVPA (c'; β = -3.13, p = .20).

CONCLUSIONS

Obesity mediated the association between length of residence and MVPA in the US immigrants. These findings may encourage long-term US immigrants to prevent and treat obesity for increasing the amount of MVPA time.

Sedentarism, Physical Activity, Steps, and Neurotrophic Factors in Obese Children

PURPOSE

This study aimed to examine the associations of sedentary time, physical activity (PA) and step-related behaviors with neurotrophic growth factors.

METHODS

A total of 97 children with overweight/obesity age 8 to 11 yr participated in this study. Sedentary time, PA, and steps were measured by GT3X+ accelerometers in hip and nondominant wrist. Estimates of light, moderate, vigorous, and moderate-to-vigorous PA (MVPA) were obtained. Steps per daytime, peak 60-, 30-, and 1-min cadence were computed. The time accumulated (min·d) in different cadence bands of steps was also computed from hip accelerometer. Plasma levels of brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF), and insulin growth factor-1 (IGF-1) were determined by the XMap technology (Luminex IS 100/200 system, Luminex Corporation, Austin, TX).

RESULTS

Light PA, moderate PA, MVPA, and the peak 60-min cadence were positively related with BDNF concentrations (all P < 0.05), and only light PA to VEGF (P = 0.048). No association was observed for IGF-1 (P > 0.05). The associations of light PA with BDNF and VEGF disappeared (all P > 0.05) after performing analyses with nondominant wrist-placement data. However, moderate PA and MVPA remained significantly associated with BDNF (both P < 0.05). The time accumulated in cadence bands of 40 to 59 steps per day and 60 to 79 steps per day (i.e., walking at slow pace) was positively associated with plasma BDNF (all P < 0.05).

CONCLUSIONS

In conclusion, PA is positively related to plasma BDNF, whereas no relationship was observed for VEGF or IGF-1. Higher amounts of time spent in slow walking cadence bands could increment BDNF levels. Exercise-based randomized controlled trials in children with overweight/obesity should be carried out to better understand the influence of PA behaviors on the neurotrophic factors.

Kinematic Comparison of Aquatic- and Land-Based Stationary Exercises in Overweight and Normal Weight Children

PURPOSE

This study examined lower extremity kinematics in healthy weight (HW) and overweight (OW) children during water- and land-based stationary exercises (stationary running, frontal kick, and butt kick) at light submaximal intensity.

METHODS

Participants included OW (N = 10; body fat percentage: 34.97 [8.60]) and HW (N = 15; body fat percentage: 18.33 [4.87]) children, aged 10 to 13 years. Spatiotemporal data, lower extremity joint kinematics, and rating of perceived exertion (RPE) were collected during water- and land-based stationary exercises. Repeated measures analysis of variance compared kinematic variables and RPE between groups and environments. A polygon area function compared coordination patterns between environments.

RESULTS

RPE responses were significantly greater in OW than HW children on land (13.6 [0.7] vs 11.6 [0.7]; P < .001), whereas the RPE responses were similar between groups in water (11.2 [0.7] vs 11.1 [0.8]; P > .05). OW children were significantly more upright than HW children during land-based exercise, whereas there were no differences observed between groups during aquatic-based exercise. The duration of stance and swing phases, angular velocity, and cadence were significantly lower in water than on land.

CONCLUSION

Compared with HW children, OW children performed stationary exercises in a more upright posture on land, with higher RPE. However, these differences diminished in water. Aquatic-based exercise may be effective in minimizing the effects of excess mass on OW children's ability to complete physical activity.

Relationships between adiposity and postural control in girls during balance tasks of varying difficulty

OBJECTIVE

This study aimed to examine associations between postural control and body composition in 8-10-year-old girls.

METHODS

An observational cross-sectional study was conducted in 47 girls who were healthy-weight/overweight/obese [body mass index (BMI) percentile]. Girls participated in six postural control conditions of varying difficulty (standing with malleoli touching, tandem stance leading with dominant and non-dominant foot, repeated with eyes open and closed). Postural control outcomes included Centre of Pressure (COP) sway area, COP principal and minor axis length and COP maximum velocity. Data were analysed using linear mixed modelling.

RESULTS

BMI percentile was positively associated with COP sway area (p=0.034) and principal axis (p=0.030) during tandem stance non-dominant foot leading with eyes closed and COP principal axis during tandem stance dominant foot leading with eyes open (p=0.045). BMI percentile significantly interacted with postural control conditions of varying difficulty to predict postural control outcomes (p≤0.035), notable for tandem stance positions [all four COP sway outcomes in tandem stance non-dominant foot leading eyes closed; tandem stance dominant foot leading with eyes open and closed (two COP sway outcomes each)].

CONCLUSIONS

Girls with greater adiposity may have impairments in postural control, but only during more challenging postural control conditions. In contrast, BMI has little role to play in girls' postural control in easier postural control conditions (standing with feet together). These findings may suggest potential functional or safety considerations when girls with overweight/obesity are performing demanding postural control tasks (such as during sport or physical activity).

A systematic review on biomechanical characteristics of walking in children and adolescents with overweight/obesity: Possible implications for the development of musculoskeletal disorders

It is known that obesity is associated with biomechanical alterations during locomotor tasks, which is considered a potential risk factor for the development of musculoskeletal disorders (MSKD). However, the association of obesity with biomechanical alterations of walking in the early stages of life have not yet been systematically reviewed. Thus, this review aims to summarize the biomechanical characteristics of walking in children and adolescents with overweight/obesity (OW/OB) versus their normal-weight (NW) counterparts. PubMed and Web of Science were systematically searched until November 2018. We found strong and moderate evidence supporting biomechanical differences in the gait pattern of OW/OB with respect to NW. Based on strong evidence, the gait patterns of OW/OB present greater pelvis transversal plane motion, higher hip internal rotation, higher hip flexion, extension and abduction moments and power generation/absorption, greater knee abduction/adduction motion, and higher knee abduction/adduction moments and power generation/absorption. Based on moderate evidence, OW/OB walk with greater step width, longer stance phase, higher tibiofemoral contact forces, higher ankle plantarflexion moments and power generation, and greater gastrocnemius and soleus activation/forces. These biomechanical alterations during walking in OW/OB could play a major role in the onset and progression of MSKD.

Effects of a lower extremity exercise program on gait biomechanics and clinical outcomes in children and adolescents with obesity: A randomized controlled trial

BACKGROUND

Research highlights the detrimental effects of obesity on gait biomechanics and the accompanied risk of lower-extremity skeletal malalignments, increased joint stress, pain and discomfort. Individuals with obesity typically show increased knee valgus angles combined with an increased step width. Accompanying muscular dysfunctions impede their ability to compensate for these alterations, especially in the frontal plane. To date, no studies are available, which evaluated the potential effects of an exercise program (EP) in reducing these unfavorable biomechanical changes.

RESEARCH QUESTIONS

Is a 12-week EP, which includes hip abductor and knee extensor strength exercises and fosters dynamic knee alignment, effective in positively altering gait biomechanics in children and adolescents with obesity?

METHODS

This study was a randomized controlled trial having children and adolescents with obesity assigned to an EP (n = 19) or control (n = 16) group. Pain, self-rated knee function, muscle strength and 3D gait analysis during walking and stair climbing were evaluated.

RESULTS

Results indicate that the EP was able to increase muscular strength especially in the hip abductors. In addition, children from the EP group walked with less maximum hip adduction and reduced pelvic drop during weight acceptance at follow-up. No changes were present in self-rated knee function, pain or discomfort.

SIGNIFICANCE

Even though effects were small, results indicate that an EP is an effective short-term possibility to counteract the progressive development of biomechanical malalignments of the lower extremity. Clinical parameters indicated that the program was feasible. Nonetheless, low adherence highlights the need to develop more attractive programs. CLINICAL TRIALS REG. NO: clinicaltrials.gov (NCT02545764).

Gait changes after weight loss on adolescent with severe obesity after sleeve gastrectomy

BACKGROUND

It has been highlighted that obesity influences the gait reducing walking velocity, stride length, ankle dorsal flexion at initial contact and ankle power generation. Meanwhile, step width, double support, hip flexion, knee extension during stance, hip moment and ankle power absorption was described increased. A tendency to the normalization of these parameters occur when subjects reduced their weight during growth.

OBJECTIVE

We studied the effect of fast weight loss due to Sleeve Gastrectomy on gait pattern of adolescent with severe obesity. The aim is to assess the functional benefit of the surgery.

SETTING

Pediatric hospital, public health, Italy.

METHODS

11 patients before and after 1 year from surgery and 10 controls participated to the study. We studied the gait with an optoelectronic system and two force plates. We evaluated both kinetics and kinematics of walking. Then we looked at the differences between the pre- vs post-surgery and with the control group.

RESULTS

Step length and velocity were lower and step width was bigger in adolescent with obesity. Kinematic and kinetic parameters were altered. After surgery we observed the reduction of several gait alteration. Meanwhile, after 1 year alterations at the level of the foot, the knee and the pelvis persist.

CONCLUSION

The sudden loss of weight highlighted the presence of long-term effects on the locomotor system. The results discourage intense walking activities before the weight loss and we suggest further studies for evaluating the necessity of a rehabilitative intervention.

A Pilot Study of Iyengar Yoga for Pediatric Obesity: Effects on Gait and Emotional Functioning

Obesity negatively impacts the kinematics and kinetics of the lower extremities in children and adolescents. Although yoga has the potential to provide several distinct benefits for children with obesity, this is the first study to examine the benefits of yoga for gait (primary outcome) in youths with obesity. Secondary outcomes included health-related quality of life (HRQoL), physical activity, and pain. Feasibility and acceptability were also assessed. Nine youths (11⁻17 years) participated in an eight-week Iyengar yoga intervention (bi-weekly 1-h classes). Gait, HRQOL (self and parent-proxy reports), and physical activity were assessed at baseline and post-yoga. Pain was self-reported at the beginning of each class. Significant improvements were found in multiple gait parameters, including hip, knee, and ankle motion and moments. Self-reported and parent-proxy reports of emotional functioning significantly improved. Time spent in physical activity and weight did not change. This study demonstrates that a relatively brief, non-invasive Iyengar yoga intervention can result in improved malalignment of the lower extremities during ambulation, as well as in clinically meaningful improvements in emotional functioning. This study extends current evidence that supports a role for yoga in pediatric obesity.

Relationship between Body Mass Index, Cardiorespiratory and Musculoskeletal Fitness among South African Adolescent Girls

Background: Cardiorespiratory and musculoskeletal fitness are important health indicators that support optimal physical functioning. Understanding the relationship between body mass index and these health markers may contribute to the development of evidence-based interventions to address obesity-related complications. The relationship between body mass index, cardiorespiratory and musculoskeletal fitness has not been well explored, particularly in female adolescents. The aim of this study was to investigate the association between body mass index, cardiorespiratory and musculoskeletal fitness among South African adolescent girls in low-income communities. Methods: This cross-sectional study included 151 adolescent girls, aged 13⁻16 years. Cardiorespiratory fitness was measured using the 20 m shuttle run test and musculoskeletal fitness was assessed using a variety of field-based tests. Height and weight were measured with standardised procedures and body mass index (BMI) was derived by the formula [BMI = weight (kg)/height (m)²]. Participants were categorised into three BMI groups using the International Obesity Task Force age- and gender-specific cut-off points. Pearson correlations were used to determine the association between body mass index, cardiorespiratory fitness and measures of musculoskeletal fitness at p ≤ 0.05. Results: Overweight and obese girls were found to have lower cardiorespiratory fitness, decreased lower extremity muscular strength, greater grip strength, and more hypermobile joints compared to normal-weight peers. BMI was negatively associated with cardiorespiratory fitness and lower extremity muscular strength. Conclusions: The findings indicate that increased body mass correlates with decreased cardiorespiratory and musculoskeletal fitness. Interventions should be developed to target these important components of physical fitness in this demographic group.

The relationship between body mass index and children's presentations to a tertiary pediatric emergency department

Background

The child obesity and its complications are associated with an alarming increased health care use, including the emergency department (ED). We evaluated the effects of the obesity and overweight in children admitted to ED, especially in patients with injury diagnosis.

Methods

A retrospective study of patients aged 6–18 years was conducted. Patients were categorized into normal weight (body mass index, BMI < 85th); overweight (BMI ≥ 85th e < 95th); obesity (BMI ≥ 95th). Multiple logistic analysis was used for estimation of risk factors associated with the BMI and to explore the association between injury diagnosis and BMI.

Results

The predictive factors associated with obesity and overweight were school age (p <  0.001), male gender (p <  0.001) and number of visits for year (obesity: p <  0.001 and overweight: p <  0.05). Obese children were less at injury risk than normal weight (p <  0.05). In injury subset, fractures in school age were more likely to occur in obesity (p <  0.01). Dislocated fractures (p <  0.01) and fractures at lower extremity were more likely to occur in obesity and overweight (p <  0.05).

Conclusions

School age children presenting to ED are more at risk of excess body weight than adolescents and are at higher fracture risk if obese and overweight. This has clear implication to support the efforts to reduce the obesity in childhood. The ED may represent a crucial setting for the early identification of these children and of co-morbidities related BMI ≥ 85th, and for a timely specialist referral of these children, especially if school age.

Biomechanical characteristics of lower limb gait waveforms: Associations with body fat in children

BACKGROUND

Childhood obesity is associated with musculoskeletal dysfunction and altered lower limb biomechanics during gait. Few previous studies have explored relationships between childhood obesity measured by body fat and lower limb joint waveform kinematics and kinetics.

RESEARCH QUESTION

What is the association between body fat and hip, knee and ankle joint angles and moments during gait and in 7 to 11 year-old boys?

METHODS

Fifty-five boys participated in the study. Body fat was measured by air displacement plethysmography. Hip, knee and ankle 3D waveforms of joint angles and moments were recorded during gait. Principle component analysis was used to reduce the multidimensional nature of the waveform into components representing parts of the gait cycle. Multiple linear regression analysis determined the association between the components with body fat.

RESULTS

Higher body fat predicted greater hip flexion, knee flexion and knee internal rotation during late stance and greater ankle external rotation in late swing/early stance. Greater hip flexion and adduction moments were found in early stance with higher body fat. In mid-stance, greater knee adduction moments were associated with high body fat. Finally, at the ankle, higher body fat was predictive of greater internal rotation moments.

SIGNIFICANCE

The study presents novel information on relationships between body fat and kinematic and kinetic waveform analysis of paediatric gait. The findings suggest altered lower limb joint kinematics and kinetics with high body fat in young boys. The findings may help to inform research in to preventing musculoskeletal comorbidities and promoting weight management.

Uphill walking: Biomechanical demand on the lower extremities of obese adolescents

The number of obesity prevalence in adolescents is still increasing. Obesity treatment programs typically include physical activity with walking being recommended as appropriate activity, but limited information exists on the demand uphill walking places on the joint loading and power of obese adolescents. Therefore, the purpose of this study was to investigate the effect of different inclinations on step characteristics, sagittal and frontal joint angles, joint moments and joint power of obese adolescents in comparison to their normal-weight peers. Eleven obese (14.5±1.41 years, BMI: 31.1±3.5kg/m²) and eleven normal-weight adolescents (14.3±1.86 years, BMI: 19.0±1.7kg/m²) walked with 1.11m/s on a ramp with two imbedded force plates (AMTI, 1000Hz) at three inclinations (level, 6°, 12°). Kinematic data were collected via an infrared-camera motion system (Vicon, 250Hz). The two-way (inclination, group) ANOVA indicated a significant effect of inclination on almost all variables analysed, with the hip joint being the most affected by inclination, followed by the knee and ankle joint. The obese participants additionally spent less time in swing phase, walked with an increased knee flexion and valgus angle and an increased peak hip flexion and adduction moment. Hip joint power of obese adolescents was especially in the steepest inclination significantly increased compared to their normal-weight peers. Obese adolescents demonstrate increased joint loading compared to their normal-weight peers and in combination with a musculoskeletal malalignment they might be prone to an increased overuse injury risk.

Guidelines for schoolbag carriage: An appraisal of safe load limits for schoolbag weight and duration of carriage

BACKGROUND

There is no global agreement on a schoolbag weight limit and little assessment of its utility. The duration of carriage is another factor yet there is no previous systematic assessment of the utility of cut-off values for it in identifying schoolbag-related discomfort.

OBJECTIVES

The objectives were to establish if there was a threshold for musculoskeletal discomfort based on (i) percentage bodyweight (% BW) of the schoolbag; (ii) duration of carriage; or (iii) combined % BW and duration.

METHODS

Using data from 462 primary school children, a novel experimental approach was used to explore the utility of conventional schoolbag weight limit guidelines and duration of carriage. A receiver operating characteristic (ROC) curve was constructed to examine the predictive performance of schoolbag weight and duration of carriage.

RESULTS

The mean schoolbag weight (4.8±1.43  kg) represented a mean 12.4±4.18% BW. Only 30.7% of the sample carried schoolbags that were ≤10% BW. The majority (76%) carried schoolbags to school for ≤10 minutes. No % BW, duration of carriage or mechanical burden criterion provided a threshold cut-off point for accurately predicting schoolbag-related discomfort.

CONCLUSIONS

Guidelines for safe schoolbag carriage that are based on mechanical factors alone could not be upheld. The association between duration of carriage and back discomfort warrants further investigation.

Do fitness and fatigue affect gait biomechanics in overweight and obese children?

The purpose of this study was to determine how an overweight or obese child's cardiorespiratory fitness level and a state of fatigue affect gait biomechanics.

METHODS

Using a three-dimensional motion analysis system, twenty-nine (female and male) overweight and obese children aged 8-11 years walked on force plates before and after being fatigued from the Progressive Aerobic Cardiovascular Endurance Run (PACER) protocol. Joint moments were calculated for the knee and hip in the frontal and sagittal planes.

RESULTS

In a non-fatigued state, peak hip and knee adductor moments showed a negative relationship with cardiorespiratory fitness level (R²=0.26, 0.26). After the subjects were fatigued, peak hip extensor (p=0.02), peak knee extensor moments (p=0.02) and peak knee adductor moments (p=0.01) showed a significant increase.

CONCLUSION

This trend illustrates that as an overweight or obese individual's fitness improves, the lower limb joint moments in the frontal plane decrease when walking. However, with the introduction of cardiorespiratory fatigue, lower limb joint moments tend to increase in the frontal and sagittal planes. Increased joint stress may have potential implications for obese children performing physical activity, as well as for clinicians who are attempting to intervene in the cycle of obesity.

Changes in Functional Mobility and Musculoskeletal Pain After Bariatric Surgery in Teens With Severe Obesity: Teen-Longitudinal Assessment of Bariatric Surgery (LABS) Study

IMPORTANCE

Severe obesity is associated with mobility limitations and higher incidence of multijoint musculoskeletal pain. It is unknown whether substantial weight loss improves these important outcomes in adolescents with severe obesity.

OBJECTIVE

To examine the association of bariatric surgery with functional mobility and musculoskeletal pain in adolescents with severe obesity up to 2 years after surgery.

DESIGN, SETTING, AND PARTICIPANTS

The Teen-Longitudinal Assessment of Bariatric Surgery Study is a prospective, multicenter, observational study, which enrolled 242 adolescents (≤19 years of age) who were undergoing bariatric surgery from March 2007 through February 2012 at 5 US adolescent bariatric surgery centers. This analysis was conducted in November 2015.

INTERVENTIONS

Roux-en-Y gastric bypass (n = 161), sleeve gastrectomy (n = 67), or laparoscopic adjustable gastric band (n = 14).

MAIN OUTCOMES AND MEASURES

Participants completed a 400-m walk test prior to bariatric surgery (n = 206) and at 6 months (n = 195), 12 months (n = 176), and 24 months (n = 149) after surgery. Time to completion, resting heart rate (HR), immediate posttest HR, and HR difference (resting HR minus posttest HR) were measured and musculoskeletal pain concerns, during and after the test, were documented. Data were adjusted for age, sex, race/ethnicity, baseline body mass index (calculated as weight in kilograms divided by height in meters squared), and surgical center (posttest HR and HR difference were further adjusted for changes in time to completion).

RESULTS

Of the 206 adolescents with severe obesity included in the study, 156 were female (75.7%), the mean (SD) age was 17.1 (1.6) years, and the mean (SD) body mass index was 51.7 (8.5). Compared with baseline, significant improvements were observed at 6 months for the walk test time to completion (mean, 376 seconds; 95% CI, 365-388 to 347 seconds; 95% CI, 340-358; P < .01), resting HR (mean, 84 beats per minute [bpm]; 95% CI, 82-86 to 74 bpm; 95% CI, 72-76), posttest HR (mean, 128 bpm; 95% CI, 125-131 to 113 bpm; 95% CI, 110-116), and HR difference (mean, 40 bpm; 95% CI, 36-42 to 34 bpm; 95% CI, 31-37). These changes in time to completion, resting HR, and HR difference persisted at 12 months and 24 months. Posttest HR further improved from 6 months to 12 months (mean, 113 bpm; 95% CI, 110-116 to 108 bpm; 95% CI, 105-111). There were statistically significant reductions in musculoskeletal pain concerns at all points.

CONCLUSIONS AND RELEVANCE

These data provide evidence that bariatric surgery in adolescents with severe obesity is associated with significant improvement in functional mobility and in the reduction of walking-related musculoskeletal pain up to 2 years after surgery.

Clinical outcome measures for monitoring physical function in pediatric obesity: An integrative review

OBJECTIVE

Measuring physical function in children with obesity is important to provide targets for clinical intervention to reduce impairments and increase participation in activities. The objective of this integrative review was to evaluate measurement properties of performance-based measures of physical function in children with overweight and obesity.

DESIGN AND METHODS

An integrative review of literature published in Cochrane Reviews, SPORTDiscus, CINAHL, PLoS, Medline, and Scopus was conducted.

RESULTS

Twenty-eight studies were eligible and represented 66 performance-based measures of physical function. Assessments of repeatability and feasibility were not conducted in the majority of performance measures reported; only 6-min-timed walk (6MTW) was examined for test-retest repeatability. Measures of flexibility, strength, aerobic performance, anaerobic performance, coordination, and balance demonstrated construct validity and responsiveness; however, findings were inconsistent across all performance-based measures. Multi-item tests of physical function demonstrated acceptable construct validity and responsiveness; however, internal consistency was not determined.

CONCLUSIONS

There is moderate evidence that 6MTW is suitable for the measurement of physical function in children with obesity. However, evidence is low for the use of aerobic and anaerobic performance, muscle strength, Movement Assessment Battery for Children, and Bruininks-Oseretsky Test of Motor Proficiency multi-item performance instruments and very low for flexibility, coordination, and balance tests. Based on this review, measurement of physical function using 6MTW is recommended.

Impaired Physical Function Associated with Childhood Obesity: How Should We Intervene?

BACKGROUND

This study examined relationships between adiposity, physical functioning, and physical activity.

METHODS

Obese (N = 107) and healthy-weight (N = 132) children aged 10-13 years underwent assessments of percent body fat (%BF, dual energy X-ray absorptiometry); knee extensor strength (KE, isokinetic dynamometry); cardiorespiratory fitness (CRF, peak oxygen uptake by cycle ergometry); physical health-related quality of life (HRQOL); and worst pain intensity and walking capacity [six-minute walk (6MWT)]. Structural equation modelling was used to assess relationships between variables.

RESULTS

Moderate relationships were observed between %BF and (1) 6MWT, (2) KE strength corrected for mass, and (3) CRF relative to mass (r -0.36 to -0.69, p ≤ 0.007). Weak relationships were found between %BF and physical HRQOL (r -0.27, p = 0.008); CRF relative to mass and physical HRQOL (r -0.24, p = 0.003); physical activity and 6MWT (r 0.17, p = 0.004). Squared multiple correlations showed that 29.6% variance in physical HRQOL was explained by %BF, pain, and CRF relative to mass; while 28.0% variance in 6MWT was explained by %BF and physical activity.

CONCLUSIONS

It appears that children with a higher body fat percentage have poorer KE strength, CRF, and overall physical functioning. Reducing percent fat appears to be the best target to improve functioning. However, a combined approach to intervention, targeting reductions in body fat percentage, reductions in pain, and improvements in physical activity and CRF may assist physical functioning.

Impaired quality of life in treatment-seeking obese children of Dutch, Moroccan, Turkish and Surinamese descent

Objective

To determine the health-related quality of life (HRQOL) of overweight and obese multi-ethnic children compared with normal-weight children; and to investigate differences in HRQOL between self- and parent-proxy reports and ethnic groups.

Design

Prospective cross-sectional study.

Setting

Out-patient clinic where children and their parents filled out a validated HRQOL questionnaire (KIDSCREEN-52) and height, weight, waist circumference and fat percentage were measured.

Subjects

Overweight and obese children, aged 8–18 years (mean BMIZ-score 3·2 (sd0·6)), from the obesity out-patient clinic.

Results

Three hundred and eight self- and 213 parent-proxy reported questionnaires were completed. Global HRQOL and the Physical Wellbeing, Moods & Emotions and Self-Perception subscales were markedly reduced in our multi-ethnic obese cohort, relative to the Dutch reference values. Parent proxies reported significantly lower on the global HRQOL and the Physical Wellbeing, Moods & Emotions and Bullying subscales. In Caucasian children, multivariate analyses showed that BMI was associated with the quality-of-life subscales Moods & Emotions, Self-Perception and Bullying.

Conclusions

HRQOL was markedly reduced in our multi-ethnic overweight and obese out-patient clinic cohort, with significantly lower parent-proxy scores compared with self-reported scores. We believe intervention programmes aiming to improve HRQOL should be directed to both parents and children, while ethnic-specific programmes to enhance HRQOL seem of less importance.

Screen-based sedentary behavior and associations with functional strength in 6-15 year-old children in the United States

BACKGROUND

Physical strength is associated with improved health outcomes in children. Heavier children tend to have lower functional strength and mobility. Physical activity can increase children's strength, but it is unknown how different types of electronic media use impact physical strength.

METHODS

Data from the NHANES National Youth Fitness Survey (NNYFS) from children ages 6-15 were analyzed in this study. Regression models were conducted to determine if screen-based sedentary behaviors (television viewing time, computer/video game time) were associated with strength measures (grip, leg extensions, modified pull-ups, plank) while controlling for potential confounders including child age, sex, BMI z-score, and days per week with 60+ minutes of physical activity. Grip strength and leg extensions divided by body weight were analyzed to provide measures of relative strength together with pull-ups and plank, which require lifting the body.

RESULTS

The results from the regression models showed the hypothesized inverse association between TV time and all strength measures. Computer time was only significantly inversely associated with the ability to do one or more pull-ups.

CONCLUSIONS

This study shows that television viewing, but not computer/videogames, is inversely associated with measures of child strength while controlling for child characteristics and physical activity. These findings suggest that "screen time" may not be a unified construct with respect to strength outcomes and that further exploration of the potential benefits of reducing television time on children's strength and related mobility is needed.

The impact of body fat on three dimensional motion of the paediatric foot during walking

Childhood obesity is commonly associated with a pes planus foot type and altered lower limb joint function during walking. However, limited information has been reported on dynamic intersegment foot motion with the level of obesity in children. The aim of this study was to explore the relationships between intersegment foot motion during gait and body fat in boys age 7-11 years. Fat mass was measured in fifty-five boys using air displacement plethysmography. Three-dimensional gait analysis was conducted on the right foot of each participant using the 3DFoot model to capture angular motion of the shank, calcaneus, midfoot and metatarsals. Two multivariate statistical techniques were employed; principle component analysis reduced the multidimensional nature of gait analysis, and multiple linear regression analysis accounted for potential confounding factors. Higher fat mass predicted greater plantarflexion of the calcaneus during the first half and end of stance phase and at the end of swing phase. Greater abduction of the calcaneus throughout stance and swing was predicted by greater fat mass. At the midfoot, higher fat mass predicted greater dorsiflexion and eversion throughout the gait cycle. The findings present novel information on the relationships between intersegment angular motion of the foot and body fat in young boys. The data indicates a more pronated foot type in boys with greater body fat. These findings have clinical implications for pes planus and a predisposition for pain and discomfort during weight bearing activities potentially reducing motivation in obese children to be physically active.

Exercise training at the intensity of maximal fat oxidation in obese boys

The objectives of this study were to explore the effects of 10 weeks of exercise training at the intensity of maximal fat oxidation rate (FATmax) on body composition, cardiovascular fitness, and functional capacity in 8- to 10-year-old obese boys. This is a school-based interventional study. Twenty-six obese boys and 20 lean boys were randomly allocated into the exercise and control groups. Measurements of body composition, FATmax through gas analyses, predicted maximal oxygen uptake, and functional capacity (run, jump, abdominal muscle function, and body flexibility) were conducted at baseline and at the end of experiments. Two exercise groups participated in 10 weeks of supervised exercise training at individualized FATmax intensities, for 1 h per day and 5 days per week. FATmax training decreased body mass (-1.0 kg, p < 0.05), body mass index (-1.2 kg/m(2), p < 0.01), fat mass (-1.2 kg, p < 0.01), and abdominal fat (-0.13 kg, p < 0.01) of the trained obese boys. Their cardiovascular fitness (p < 0.05) and body flexibility (p < 0.05) were also improved after training. The lean boys showed improvements in cardiovascular fitness after training (p < 0.05). FATmax training increased the FATmax in obese boys from 0.35 ± 0.12 g/min to 0.38 ± 0.13 g/min, but this change was not statistically significant. In addition, there was no change in daily energy intake for all participants before and after the experimental period. Results of this study suggest that FATmax is an effective exercise training intensity for the treatment of childhood obesity.

The effects of a strength and neuromuscular exercise programme for the lower extremity on knee load, pain and function in obese children and adolescents: study protocol for a randomised controlled trial

BACKGROUND

Childhood obesity is one of the most critical and accelerating health challenges throughout the world. It is a major risk factor for developing varus/valgus misalignments of the knee joint. The combination of misalignment at the knee and excess body mass may result in increased joint stresses and damage to articular cartilage. A training programme, which aims at developing a more neutral alignment of the trunk and lower limbs during movement tasks may be able to reduce knee loading during locomotion. Despite the large number of guidelines for muscle strength training and neuromuscular exercises that exist, most are not specifically designed to target the obese children and adolescent demographic. Therefore, the aim of this study is to evaluate a training programme which combines strength and neuromuscular exercises specifically designed to the needs and limitations of obese children and adolescents and analyse the effects of the training programme from a biomechanical and clinical point of view.

METHODS/DESIGN

A single assessor-blinded, pre-test and post-test randomised controlled trial, with one control and one intervention group will be conducted with 48 boys and girls aged between 10 and 18 years. Intervention group participants will receive a 12-week neuromuscular and quadriceps/hip strength training programme. Three-dimensional (3D) gait analyses during level walking and stair climbing will be performed at baseline and follow-up sessions. The primary outcome parameters for this study will be the overall peak external frontal knee moment and impulse during walking. Secondary outcomes include the subscales of the Knee injury and Osteoarthritis Outcome Score (KOOS), frontal and sagittal kinematics and kinetics for the lower extremities during walking and stair climbing, ratings of change in knee-related well-being, pain and function and adherence to the training programme. In addition, the training programme will be evaulated from a clinical and health status perspective by including the following analyses: cardiopulmonary testing to quantify aerobic fitness effects, anthropometric measures, nutritional status and psychological status to characterise the study sample.

DISCUSSION

The findings will help to determine whether a neuromuscular and strength training exercise programme for the obese children population can reduce joint loading during locomotion, and thereby decrease the possible risk of developing degenerative joint diseases later in adulthood.

TRIAL REGISTRATION

ClinicalTrials NCT02545764 , Date of registration: 24 September 2015.

Painful Flexible Flatfoot

Flatfoot is commonly encountered by pediatric orthopedic surgeons and pediatricians. A paucity of literature exists on how to define a flatfoot. The absence of the medial arch with a valgus hindfoot is the hallmark of this pathology. Flatfoot can be flexible or rigid. This review focuses on the diagnosis and treatment of the flexible flatfoot. Most flatfeet are flexible and clinically asymptomatic, and warrant little intervention. If feet are symptomatic, treatment is needed. Most patients who require treatment improve with foot orthotics and exercises. Only feet resistant to conservative modalities are deemed surgical candidates. The presence of a tight heel cord is often found in patients who fail conservative management.

Schoolbag carriage and schoolbag-related musculoskeletal discomfort among primary school children

Schoolbag carriage is a common occurrence and has been associated with musculoskeletal discomfort in children. The current study investigated the relationship between schoolbag-related musculoskeletal discomfort and individual, physical and psychosocial risk factors in primary school children in Ireland. A cross-sectional survey and pretest-posttest quasi-experimental design was used. The site and intensity of musculoskeletal discomfort was assessed before and after schoolbag carriage to provide a dose-response assessment of schoolbag-related discomfort for the first time. Objective measurements of the children, schoolbags and other additional items were made, and a researcher assisted questionnaire was completed on arrival at school. A total of 529 children (male 55.8%: female 44.2%) with a mean age of 10.6 years ± 7.14 months were included. The majority had backpacks (93.8%) and 89.7% (n = 445) carried the backpack over 2 shoulders. The mean schoolbag weight (4.8 ± 1.47 kgs) represented a mean % body weight (%BW) of 12.6 ± 4.29%. Only 29.9% carried schoolbags that were ≤10%BW. A significantly greater proportion of normal weight children carried schoolbags that were >10%BW compared to overweight/obese children (p < 0.001). The mean %BW carried was 18.3 ± 5.03 for those who had an additional item. The majority (77.5%) carried schoolbags to school for ≤10 min. The prevalence of baseline musculoskeletal discomfort was high (63.4%). Schoolbag-related discomfort was reported more frequently in the shoulders (27.3%) than in the back (15%). The dose-response assessment indicated that both statistically and meaningfully significant increases in discomfort were observed following schoolbag carriage. Multiple logistic regression models indicated that psychosocial factors and a history of discomfort were predictors of schoolbag-related back discomfort, while gender (being female) and a history of discomfort were predictors of schoolbag-related shoulder discomfort. None of the physical factors (absolute/relative schoolbag weight, carrying an additional item, duration of carriage, method of travel to school) were associated with schoolbag-related discomfort. This study highlights the need to consider the multi-factorial nature of schoolbag-related discomfort in children, and also the need to identify background pain as its presence can inadvertently influence the reporting of 'schoolbag-related' discomfort if it is not accounted for.

Bone Characteristics and Their Determinants in Adolescents and Young Adults with Early-Onset Severe Obesity

Childhood obesity is associated with compromised bone health. We studied bone characteristics and their determinants in obese young adults. The study included 68 subjects with early-onset severe obesity and 73 normal-weight controls. Data on physical activity (PA), diet and smoking were collected. Bone characteristics were measured using peripheral QCT. The obese and control subjects were similar in age (mean 19.6 ± 2.6 years) and height but BMIs differed (39.7 and 22.6 kg/m(2)). A clustering of unhealthy lifestyles was marked: Obese subjects reported less supervised PA in childhood, adolescence and currently (p < 0.03) and were more likely to smoke (p = 0.005), and had a lower healthy eating index (HEI) (p = 0.007) but similar alcohol consumption compared with controls. In obese women, all crude bone characteristics were higher than in controls; in men, the differences were smaller. Associations of lifestyle factors with bone characteristics were tested using partial correlations. Independently of BMI, supervised PA in adolescence and alcohol consumption were related positively to bone characteristics in both groups. HEI associated positively with bone characteristics only in controls, while smoking was a positive determinant of bone characteristics only in obese subjects. The multivariate model showed that the contribution of lifestyle factors to bone characteristics was minimal compared with BMI. Early-onset obesity is accompanied by poor dietary quality, sedentary lifestyle, and more frequent smoking, but the overall contribution of these lifestyle factors to bone strength is limited. Bone strength is more likely to be compromised in men and in unloaded bone sites in subjects with early-onset severe obesity. The impact of obesity-related endocrine changes on bone characteristics need to be evaluated in future studies.

Relation of intelligence quotient and body mass index in preschool children: a community-based cross-sectional study

OBJECTIVE

Overweight and obesity in children is a global problem. Besides physical effects, obesity has harmful psychological effects on children.

METHODS

We carried out cross-sectional community-based study to investigate the relation between body mass index (BMI) and cognitive functioning in preschool children. Thirteen socioeconomical elements of 1151 children were measured and analyzed based on their intelligence quotient (IQ) test results. Thirteen out of 33 provinces were selected randomly, and schools were selected as clusters in rural and urban areas. Descriptive statistics, t-test, analysis of variance and regression were used when appropriate.

RESULTS

Our analysis showed that IQ was associated with household income, place of residence, delivery type, type of infant feeding and father's and mother's education level (P<0.001 for all). Using penalized linear regression for eliminating the impact of confounding factor, our study shows that, living in metropolitan (β=2.411) and urban areas (β=2.761), the level of participants' father's education (β=5.251) was positively and BMI (β=-0.594) was negatively related with IQ test results.ConclusionsThe findings of the present study showed that a lower IQ score is associated with higher BMI. However, this relation appears to be largely mediated when the socioeconomic status was considered.

Service evaluation of the GOALS family-based childhood obesity treatment intervention during the first 3 years of implementation

OBJECTIVES

To evaluate the impact of the GOALS (Getting Our Active Lifestyles Started) family-based childhood obesity treatment intervention during the first 3 years of implementation.

DESIGN

Single-group repeated measures with qualitative questionnaires.

SETTING

Community venues in a socioeconomically deprived, urban location in the North-West of England.

PARTICIPANTS

70 overweight or obese children (mean age 10.5 years, 46% boys) and their parents/carers who completed GOALS between September 2006 and March 2009.

INTERVENTIONS

GOALS was a childhood obesity treatment intervention that drew on social cognitive theory to promote whole family lifestyle change. Sessions covered physical activity (PA), diet and behaviour change over 18 2 h weekly group sessions (lasting approximately 6 months). A Template for Intervention Description and Replication (TIDieR) checklist of intervention components is provided.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure was child body mass index (BMI) z-score, collected at baseline, post-intervention and 12 months. Secondary outcome measures were child self-perceptions, parent/carer BMI and qualitative changes in family diet and PA (parent/carer questionnaire).

RESULTS

Child BMI z-score reduced by 0.07 from baseline to post-intervention (p<0.001) and was maintained at 12 months (p<0.05). There was no change in parent/carer BMI or child self-perceptions, other than an increase in perceived social acceptance from baseline to post-intervention (p<0.05). Parents/carers reported positive changes to family PA and dietary behaviours after completing GOALS.

CONCLUSIONS

GOALS completion was associated with small improvements in child BMI z-score and improved family PA and dietary behaviours. Several intervention modifications were necessary during the implementation period and it is suggested childhood obesity treatment interventions need time to embed before a definitive evaluation is conducted. Researchers are urged to use the TIDieR checklist to ensure transparent reporting of interventions and facilitate the translation of evidence to practice.

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.

Analysis of the relationships that body composition and muscular strength have with oxygen cost of walking in children with cerebral palsy

OBJECTIVE

To investigate whether body composition and lower extremity strength relate to oxygen cost of walking in children with cerebral palsy (CP), and to evaluate the relative contributions of these measures to explain variation in oxygen cost seen in this population.

METHODS

A total of 116 children with spastic diplegic CP, Gross Motor Function Classification System levels I-III, aged 8-18 participated. Strength, body composition (body mass index (BMI) and percent body fat) and oxygen cost were recorded. Pearson correlations assessed relationships between variables of body composition and strength to oxygen cost. Forward stepwise linear regression analyzed variance explained by strength and body composition measures. Oxygen data were analyzed by weight status classifications using one-way analysis of variance with significance set at p<0.05.

RESULTS

Total strength (r=-0.27) and total extensor strength (r=-0.27) had fair inverse relationships with oxygen cost. Total extensor strength explained 7.5% (r(2)=0.075, beta=-0.274, p<0.01) of the variance in oxygen cost. Body composition did not explain significant variance in oxygen cost, however significant differences were found in oxygen consumption (p=0.003) and walking velocity (p=0.042) based on BMI weight classifications.

CONCLUSIONS

For ambulatory children with CP, oxygen cost during walking can be partially explained by total extensor strength and not body composition. However, those categorized as obese may adjust to a slower walking speed to keep their oxygen cost sustainable, which may further affect their ability to keep up with typically developing peers and possibly lead to greater fatigue.

Musculoskeletal Function and Obesity: Implications for Physical Activity

However quantified, obesity is a global health problem of significant magnitude. The condition is no longer limited to the developed world, with an increasing proportion of low-to-middle income countries burdened by obesity and its comorbidities. Specifically, obesity is a risk factor for a raft of psychosocial, physiological, cardiovascular, and metabolic problems. The carriage of excess body weight, including an unhealthy proportion of body fat, also has important implications for musculoskeletal health. To date, this important relationship has not received as much attention by the research community. Coincidentally, there has been a heightened interest in the role of physical activity and exercise across the lifespan in the prevention, treatment and management of obesity. This paper considers some of the more common musculoskeletal problems in children, adolescents and adults with implications for the overweight and obese and their meaningful engagement in physical activity.

The effects of pediatric obesity on dynamic joint malalignment during gait

BACKGROUND

There is a greater prevalence of lower extremity malalignment in obese children during static posture; however, there has been less examination of dynamic joint function in this cohort. Therefore, the purpose of this study was to determine kinematic differences that exist between obese and non-obese children that would support previously reported static joint malalignment.

METHODS

Forty children were classified as obese (n=20) or non-obese (n=20). Lower extremity joint kinematics were collected during five walking trials at a self-selected pace. Peak joint displacement and amount of joint motion throughout the gait cycle (calculated as the integrated displacement curve) were analyzed for group differences.

FINDINGS

Non-obese children had greater peak knee and hip extension during gait; however, there were no group differences in the integrated sagittal displacement curve. Obese children had greater peak angular displacement and integrals of angular displacement for peak hip adduction, hip internal rotation, and foot abduction (toe-out) than non-obese children. Obese children also had greater peak knee external rotation than non-obese children.

INTERPRETATION

Non-obese children showed greater range of motion in the sagittal plane, particularly at the hip and knee. Frontal and transverse plane differences suggest that obese children function in a more genu valgum position than non-obese children. Static measures of genu valgum have been previously associated with pediatric obesity; the findings indicate that there are also dynamic implications of said malalignment in obese children. Genu valgum presents increased risk of osteoarthritis for obese children and should be considered when prescribing weight bearing exercise to this cohort.

Pain is Associated with Physical Activity and Health-Related Quality of Life in Overweight and Obese Children

This study examined associations between pain, physical activity, physical fitness, and health-related quality of life (HRQOL) in overweight and obese children. Participants were 270 overweight and obese children 8-12 years of age and their parents. Children were separated into No Pain Frequency, Low Pain Frequency, and High Pain Frequency groups. Children in the Low Pain Frequency group spent less time in moderately intense physical activities compared to the No Pain Frequency group. Children in the High Pain Frequency group reported significantly lower HRQOL in most domains of functioning compared to children in the No Pain and Low Pain Frequency groups. Pain in overweight and obese children may negatively impact physical activity and HRQOL and should be assessed and treated in research and clinical work.

Functional impairment in obesity: a focus on knee and back pain

SUMMARY Cross-sectional and longitudinal evidence strongly indicate that obesity is related to physical impairment and joint pain, particularly in the lumbar spine, sacroiliac and knee joints. What is most disturbing is that obese children under 15 years are now reporting joint pain and cannot perform functional tasks as well as their nonobese counterparts. As the prevalence of obesity rises, so do the rates of musculoskeletal disease and physical dysfunction. Functional tasks that involve supporting or transferring body weight are typically painful and difficult to perform. Of most concern is that some of these tasks are simply impossible depending on the severity of obesity. As a consequence, the individual's quality of life suffers. A BMI of 35 kg/m(2) is emerging as the threshold at which functional impairment rates rise dramatically. To restore functional independence and optimize functional gains over the long term, a combination of treatments for the obese patient with joint pain may be effective. The initial use of physical therapy, pain medications or joint viscosupplementation, coupled with diet, exercise, or bariatric surgery are options for weight loss and reduction of pain symptoms. Irrespective of age, weight loss can reduce or eliminate joint pain. As body weight is reduced, so should the reliance on medication with a concomitant improvement in functional mobility.

The effect of a weight management program on postural balance in obese children

The present study aimed to investigate whether obese children improve their balance and postural performance following a 6-month-weight management program. Twenty-nine obese children aged 6-14 years were examined posturographically before and after participation in weight management program. The interactive balance system evaluated the stability index, Fourier spectral analysis, weight distribution index, and falling index. The performance was evaluated for eight positions requiring closure of eyes, standing on pillows, as well as head turns. Anthropometric measurements (e.g., weight, height, BMI, and BMI percentiles) were also determined before and after the intervention. We found significant increase in height and significant decreased in BMI percentile following the intervention program (p<.05). Pre-intervention BMI percentile was found to be correlated with stability index in most of the positions measured (e.g., normal open position=.464; p=.011). Following the intervention program, an interaction was found between BMI percentile differences (pre- versus post-interventional) and balance (stability index and F2-F4 frequencies of most standing positions). Furthermore, a correlation was found between general stability and the falling index (.446; p=.015). Regression analysis showed that only initial weight distribution index and post-intervention BMI entered the equation as predictors of post-intervention weight distribution index.

CONCLUSION

Weight management program for childhood obesity improved stability, reduced potential vestibular stress/disturbances, and decreased falling probability of the participants. Further longitudinal studies are needed to verify the relationship between physical activity, weight loss, and reduction of subsequent injuries in obese children.

The application of computer musculoskeletal modeling and simulation to investigate compressive tibiofemoral force and muscle functions in obese children

This study aimed to utilize musculoskeletal modelling and simulation to investigate the compressive tibiofemoral force and individual muscle function in obese children. We generated a 3D muscle-driven simulation of eight obese and eight normal-weight boys walking at their self-selected speed. The compressive tibiofemoral force and individual muscle contribution to the support and progression accelerations of center of mass (COM) were computed for each participant based on the subject-specific model. The simulated results were verified by comparing them to the experimental kinematics and EMG data. We found a linear relationship between the average self-selected speed and the normalized peak compressive tibiofemoral force (R² = 0.611). The activity of the quadriceps contributed the most to the peak compressive tibiofemoral force during the stance phase. Obese children and nonobese children use similar muscles to support and accelerate the body COM, but nonobese children had significantly greater contributions of individual muscles. The obese children may therefore adopt a compensation strategy to avoid increasing joint loads and muscle requirements during walking. The absolute compressive tibiofemoral force and muscle forces were still greater in obese children. The long-term biomechanical adaptations of the musculoskeletal system to accommodate the excess body weight during walking are a concern.