Effects of supervised exercise program on metabolic function in overweight adolescents

Effects of Exercise on the Resting Heart Rate: A Systematic Review and Meta-Analysis of Interventional Studies

Resting heart rate (RHR) is positively related with mortality. Regular exercise causes a reduction in RHR. The aim of the systematic review was to assess whether regular exercise or sports have an impact on the RHR in healthy subjects by taking different types of sports into account. A systematic literature research was conducted in six databases for the identification of controlled trials dealing with the effects of exercise or sports on the RHR in healthy subjects was performed. The studies were summarized by meta-analyses. The literature search analyzed 191 studies presenting 215 samples fitting the eligibility criteria. 121 trials examined the effects of endurance training, 43 strength training, 15 combined endurance and strength training, 5 additional school sport programs. 21 yoga, 5 tai chi, 3 qigong, and 2 unspecified types of sports. All types of sports decreased the RHR. However, only endurance training and yoga significantly decreased the RHR in both sexes. The exercise-induced decreases of RHR were positively related with the pre-interventional RHR and negatively with the average age of the participants. From this, we can conclude that exercise-especially endurance training and yoga-decreases RHR. This effect may contribute to a reduction in all-cause mortality due to regular exercise or sports.

Metabolic characteristics of Appalachian children

PURPOSE

The purpose of this investigation is to assess the physiological characteristics and the resting metabolic rates of a representative population of children in Buchanan County in order to identify those factors that may be contributing to the predisposition for being overweight or obese and provide nutritional and physical activity guidance for prevention.

METHODS

Twenty-three volunteers from grades 5, 6 and 7 from Buchannan County, VA underwent parametric and metabolic testing over three consecutive years in order to determine their height, weight, BMI, percent body fat, resting oxygen consumption (VO₂), resting energy expenditure (REE), respiratory exchange ratio (RER) and daily energy expenditure (DEE) and consumption.

RESULTS

Over the 3 year study period, subjects' BMI increased significantly over time (p = 0.001) while there were no changes in their, REE, RER, VO₂, percent fat and DEE. However, there was a moderate negative correlation between VO₂ and BMI in grade 5 (r = -0.578, p = 0.002), grade 6 (r = -0.477, p = 0.015) and grade 7 (r = -0.438, p = 0.023). Gender specific differences in percent body fat were evident among subjects during the last two measurement cycles and were strongly correlated with BMI (r = 0.907, r = 0.959, p = 0.000).

CONCLUSIONS

The use of resting VO₂, REE, and RER values as a screening tool for identifying those children or adolescents at risk for becoming overweight or obese is most likely cost and time prohibitive due to the need for several repeated measures to ensure accurate results. However increased VO₂ is correlated with decreased BMI.

Exercise and adiposity in overweight and obese children and adolescents: protocol for a systematic review and network meta-analysis of randomised trials

INTRODUCTION

Overweight and obesity is a worldwide public health problem among children and adolescents. However, the magnitude of effect, as well as hierarchy of exercise interventions (aerobic, strength training or both), on selected measures of adiposity is not well established despite numerous trials on this issue. The primary purposes of this study are to use the network meta-analytical approach to determine the effects and hierarchy of exercise interventions on selected measures of adiposity in overweight and obese children and adolescents.

METHODS AND ANALYSIS

Randomised exercise intervention trials >4 weeks, available in any language up to 31 August 2017 and which include direct and/or indirect evidence, will be included. Studies will be located by searching seven electronic databases, cross-referencing and expert review. Dual selection and abstraction of data will occur. The primary outcomes will be changes in body mass index (in kg/m²), fat mass and percent body fat. Risk of bias will be assessed using the Cochrane Risk of Bias assessment instrument while confidence in the cumulative evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation instrument for network meta-analysis. Network meta-analysis will be performed using multivariate random-effects meta-regression models. The surface under the cumulative ranking curve will be used to provide a hierarchy of exercise treatments (aerobic, strength or both).

ETHICS AND DISSEMINATION

This study does not require ethics approval. Findings will be presented at a professional conference and published in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD 42017073103 .

Impact of child summertime obesity interventions on body mass index, and weight-related behaviours: a systematic review and meta-analysis protocol

INTRODUCTION

In previous studies, it has been found that on average, children consistently gained weight during the summer months at an increased rate compared with the 9-month school year. This contributed to an increased prevalence of overweight and obesity in children. Several obesity-related interventions have occurred during or targeting the summer months. We propose to conduct a systematic review and meta-analysis of the impact of obesity prevention and treatment interventions for school-age children conducted during the summer or targeting the summer months when children are not in school on their body mass index (BMI), or weight-related behaviours.

METHODS AND ANALYSES

A literature search will be conducted by the first author (JPM) using MEDLINE/PubMed, Cochrane Library, Scopus, CINAHL, PsycINFO, EMBASE and Proquest Dissertations and Theses databases from the date of inception to present. Studies must examine interventions that address the modification or promotion of weight-related behaviours (eg, dietary patterns, eating behaviours, physical activity (PA), sedentary behaviour or sleep) and target school-age children (ages 5-18). The primary outcomes will be changes from baseline to postintervention and/or the last available follow-up measurement in weight, BMI, BMI percentile, standardised BMI or per cent body fat. Secondary outcomes will include changes in dietary intake, PA, sedentary behaviour or sleep. Risk of bias will be assessed using the Cochrane risk of bias tool for randomised and non-randomised studies, as appropriate.

ETHICS AND DISSEMINATION

Because this is a protocol for a systematic review, ethics approval will not be required. The findings will be disseminated via presentations at scientific conferences and published in a peer-reviewed journal. All amendments to the protocol will be documented and dated and reported in the PROSPERO trial registry.

PROSPERO REGISTRATION NUMBER

CRD42016041750.

The effect of a multi-component camp-based weight-loss program on children's motor skills and physical fitness: a randomized controlled trial

Background

Many weight-loss programs in children are performed without specific foci on training both physical fitness and motor skills. The aim of this study was to describe the effect of a one-year weight-loss program on children’s motor skills and physical fitness.

Methods

Participants included 115 overweight fifth-grade children (12.0 years) randomized into either a Day-Camp Intervention Arm (DCIA), with a subsequent family-based support program or a low-intense Standard Intervention Arm (SIA). Physical fitness was assessed by vertical jump, hand grip strength, and a progressive cardio-respiratory fitness test. Motor skills were assessed by the Movement Assessment Battery for Children – second edition (M-ABC-2), age band 3.

Results

Loss to follow-up after 52 weeks was 19 % and 32 % in the DCIA and SIA, respectively. Balance skills were improved post-camp, but not after 52 weeks in children from the DCIA compared to the SIA. Contrary to the expected, children from the SIA improved aiming and catching skills relative to the DCIA children. Overall z-scores of the physical fitness components and cardio-respiratory fitness improved more in children from the DCIA compared to children from the SIA.

Conclusion

In conclusion, the day-camp intervention led to improvements in physical fitness but not in motor skills compared to the standard intervention. Including both motor skills and physical fitness could advantageously be considered in future immersive intervention programmes.

Trial registration

Clinicaltrials NCT01574352, March 26, 2012 (retrospectively registered).

A Multi-Component Day-Camp Weight-Loss Program Is Effective in Reducing BMI in Children after One Year: A Randomized Controlled Trial

The objective of the present study was to evaluate the effectiveness of a one-year multi-component immersive day-camp weight-loss intervention for children with overweight and obesity. The study design was a parallel-group randomized controlled trial. One hundred fifteen 11-13-year-old children with overweight and obesity were randomized into either: A six-week day-camp intervention arm focusing on increased physical activity, and healthy diet followed by a subsequent one-year family-based intervention, or a standard intervention arm consisting of one weekly exercise session for six weeks. Body mass index (BMI) was the primary outcome. BMI z-score, clustered cardiovascular risk z-score, and body composition were secondary outcomes. All outcomes were measured at baseline, six week-, and 52 week follow-up. After six weeks, children from the day-camp intervention arm had improved their BMI (-2.2 kg/m² (95% CI -2.6 to -1.7, P<0.001)) and all secondary outcomes when compared to the children from the standard intervention arm. After 52 weeks, the day-camp intervention arm had a lower BMI (-1.2 kg/m² (95% CI -1.8 to -0.5, P = 0.001)), and BMI z-score (-0.20 (95% CI -0.35 to -0.05, P = 0.008)), and clustered cardiovascular risk z-score (-0.23 (95% CI -0.37 to -0.08, P = 0.002)) compared to the standard intervention arm. No group differences were detected in body composition after 52 weeks. This study shows that the day-camp intervention arm is effective in reducing BMI and improving the metabolic health of children with overweight and obesity. However, the effects seem to be diminishing over time.

Impacts of coordinative training on normal weight and overweight/obese children's attentional performance

This study investigated the efficacy of a physical activity (PA) program to improve the attention span in normal weight vs. overweight/obese children. The study was designed as a cluster-randomized controlled intervention. One hundred fifty-seven normal weight and overweight/obese primary school children were randomly divided in three cohorts: Traditional PA, Coordinative PA and a Control group (not attending any PA). Before and after 5 months of intervention, children were administered the d2-R test of attention. Results showed that participants’ attentional performances were significantly affected by Time (pre vs. post; P < 0.01) and by Time × Group interaction (traditional vs. coordinative vs. control; P < 0.001), revealing significant different effects of intervention/exercise modality on children’s attentional performance, independently of their weight status. These data suggest that a 5-month school-based PA intervention can improve the cognitive performance in children. Further, the Coordinative PA intervention resulted in the most significant improvement in children’s attention.

Obesity, fitness, and brain integrity in adolescence

OBJECTIVE

We set out to ascertain the relationship between insulin resistance, fitness, and brain structure and function in adolescents.

DESIGN AND METHODS

We studied 79 obese and 51 non-obese participants who were recruited from the community, all without type 2 diabetes mellitus. All participants received medical, endocrine, neuropsychological, and MRI evaluations as well as a 6-minute walk test that was used to estimate fitness (maximal oxygen consumption).

RESULTS

Obese adolescents had significantly thinner orbitofrontal cortices and performed significantly worse on Visual Working Memory tasks and the Digit Vigilance task. Insulin sensitivity and maximal oxygen consumption (VO2 max) were both highly correlated with central obesity and orbitofrontal cortical thickness, although insulin sensitivity was the stronger predictor for orbitofrontal cortical thickness. We also found that VO2 max was the only significant physiological variable related to visual working memory.

CONCLUSIONS

This is the first study to report positive associations between insulin resistance, VO2 max, and frontal lobe brain integrity in adolescents. Given the importance of brain health for learning and school performance, we conclude that schools should also emphasize physical fitness in order to maintain structural and functional brain integrity and facilitate academic achievement.