Exercise In Obese Adolescents Research Articles

High-Intensity Interval Exercise with Blood Flow Restriction Improves Vascular Function in Obese Male Adolescents

Study purpose. Obesity, a chronic metabolic disease is on the rise among children and adolescents and is a leading cause of mortality in adults worldwide. It is imperative to prevent obesity in children to lower the risk of adult obesity and cardiovascular diseases. Considering the effectiveness of exercise program, high-intensity interval exercise with blood flow restriction (HIIE-BFR) may have potential beneficial effects on the vascular functions of obese individuals. This study aimed to compare the acute effects of supramaximal high-intensity interval exercise (HIIE-SUPRA) and HIIE-BFR on the vascular function in obese adolescents. Materials and methods. The subjects were adolescent males aged 13 to 15. The crossover study was divided into two trials. The first trial was a pilot study involving five obese adolescent males whose heart rates were evaluated under four conditions of exercise: 1) HIIE-SUPRA at 170% (VO₂peak), 2) HIIE-BFR at 85% VO₂peak with 40% arterial occlusion pressure (AOP), 3) 60% AOP, and 4) 80% AOP. The second trial was conducted on ten obese adolescent males who performed HIIE-SUPRA and HIIE-BFR exercises separately, each for at least three days. Data collection was done to analyze the vascular function parameters before and after exercising (immediately, 10 min, 30 min, and 60 min after). Results. The results of the first trial showed that the mean heart rate of HIIE-BFR at 40% AOP was similar to that of HIIE-SUPRA (p>0.05). In the second trial, both types of exercises showed similar outcomes, with increased flow-mediated dilatation (FMD), while brachial-ankle pulse wave velocity (baPWV) decreased after exercise as compared to the baseline values (before exercise) (p<0.05). However, HIIE-BFR at 40% AOP demonstrated a lower rate of perceived exertion (RPE) as compared to HIIE-SUPRA (p<0.05). Conclusions. HIIE-BFR at 40% AOP was effective in regulating the RPE and acutely increasing the vascular function after exercise in obese adolescents, similar to HIIE-SUPRA.

Single 30min treadmill exercise session suppresses the production of pro-inflammatory cytokines and oxidative stress in obese female adolescents.

Regular treadmill exercise may result in changes in pro-inflammatory cytokines and oxidative stress. However, the way acute treadmill exercise mechanisms affect the changes in pro-inflammatory cytokines and oxidative stress in obese has not been comprehensively exposed. This study aimed to analyze the pro-inflammatory cytokines and oxidative stress between 30min before treadmill exercise and 24h after treadmill exercise in obese adolescents. A total of 20 obese females aged 19-24years were recruited from female students and given one session of treadmill exercise with an intensity of 60-70% HRmax. Thiobarbituric acid reactive substance (TBARS) was used to analyze serum levels of MDA, while enzyme-linked immunosorbent assay (ELISA) was used to analyze serum levels of TNF-α and IL-6. Moreover, the independent samples t-test with a significance level of 5% was employed to have the statistical analysis. The results on 24h after treadmill exercise and delta (Δ) between CTRL and TREG showed a significant difference (p<0.001). This study found a decrease in pro-inflammatory cytokines and oxidative stress 24h after treadmill exercise in obese adolescents. Therefore, treadmill exercise can be a promising strategy for preventing adolescents from obesity as well as preventing disease risks associated with oxidative stress and chronic inflammation.

Ergogenic effects of beetroot juice supplementation during severe-intensity exercise in obese adolescents.

Previous studies showed a higher O2 cost of exercise, and therefore, a reduced exercise tolerance in patients with obesity during constant work rate (CWR) exercise compared with healthy subjects. Among the ergogenic effects of dietary nitrate ([Formula: see text]) supplementation in sedentary healthy subjects, a reduced O2 cost and enhanced exercise tolerance have often been demonstrated. The aim of this study was to evaluate the effects of beetroot juice (BR) supplementation, rich in [Formula: see text], on physiological variables associated with exercise tolerance in adolescents with obesity. In a double-blind, randomized crossover study, 10 adolescents with obesity (8 girls, 2 boys; age = 16 ± 1 yr; body mass index = 35.2 ± 5.0 kg/m2) were tested after 6 days of supplementation with BR (5 mmol [Formula: see text] per day) or placebo (PLA). Following each supplementation period, patients carried out two repetitions of 6-min moderate-intensity CWR exercise and one severe-intensity CWR exercise until exhaustion. Plasma [Formula: see text] concentration was significantly higher in BR versus PLA (108 ± 37 vs. 15 ± 5 μM, P < 0.0001). The O2 cost of moderate-intensity exercise was not different in BR versus PLA (13.3 ± 1.7 vs. 12.9 ± 1.1 ml·min-1·W-1, P = 0.517). During severe-intensity exercise, signs of a reduced amplitude of the O2 uptake slow component were observed in BR, in association with a significantly longer time to exhaustion (561 ± 198 s in BR vs. 457 ± 101 s in PLA, P = 0.0143). In obese adolescents, short-term dietary [Formula: see text] supplementation is effective in improving exercise tolerance during severe-intensity exercise. This may prove to be useful in counteracting early fatigue and reduced physical activity in this at-risk population.

Aerobic exercise improves endothelial function and serum adropin levels in obese adolescents independent of body weight loss

Adropin is a secreted protein that regulates endothelial function. However, adropin levels in obese adolescent patients are currently uncertain. Therefore, we evaluated the association between plasma adropin levels and vascular endothelial function and investigated the effect of aerobic exercise in obese adolescents. A total of 45 obese adolescents and 20 controls (age 16–19 years) were included in our study. The obese adolescents received 12 weeks of aerobic exercise training. Serum adropin was detected using enzyme-linked immunosorbent assay. Vascular reactive hyperemia indexes (RHIs) were obtained using Endo-PAT2000. Adropin levels and RHI were significantly lower in obese adolescents than in normal-weight adolescents. Adropin levels and RHI increased significantly independently of changes in body weight after an exercise intervention (P < 0.01). Pearson correlation analysis revealed that adropin levels positively correlated with HDL-C levels (r = 0.389, P < 0.01) and RHI (r = 0.32, P < 0.01). Multiple linear stepwise regression analysis showed that the insulin resistance index (t = −3.301, P < 0.01) and HDL-C level (t = 2.620, P = 0.011) were independent risk factors of adropin levels. In addition, Δadropin (t = 3.261, P < 0.01) was an independent influencing factor of ΔRHI. Our findings suggest that adropin plays an important role in vascular endothelial function in obese adolescents.

Reduced neural responses to food cues might contribute to the anorexigenic effect of acute exercise observed in obese but not lean adolescents

Acute exercise has been found to reduce subsequent energy intake in obese adolescents. Although it has been suggested that some neural pathways are involved in this post-exercise energy intake regulation, it remains unknown whether the post-exercise attentional response to food cues differs as a function of weight status. We hypothesize that there will be a reduction in the neural response to food cues as a result of exercise in obese adolescents, but not in their lean counterparts. Fourteen obese and 14 lean adolescent boys (12-15 years) were randomized (within-subjects design) to remain seated (CON) or to exercise 45 minutes at 65% of their maximal capacities (EX). After the exercise or sitting period, the adolescents' cognitive engagement in the processing of food vs. non-food cues was assessed during an attentional computer-based task with electroencephalography (EEG) recording. An ad libitum lunch meal was offered and appetite feelings were assessed (visual analog scales). There was no main effect of condition on energy intake in lean subjects, but obese adolescents ate significantly less following EX compared with CON (P<.05). There was no effect of condition or stimulus type (food vs. non-food) on the EEG-recorded amplitude of the P3b component in lean adolescents. However, the response to food cues was significantly reduced compared with non-food stimuli after exercise in obese participants (P<.01). Following EX, but not CON, total body weight, body mass index, and fat mass were inversely correlated with the EEG response to food–non-food stimuli (all P<.05). However, this response was not associated with ad libitum EI (both P>.1). Acute exercise favors decreased neural response to food cues compared with non-food cues in obese but not lean adolescents, suggesting differential effects of exercise on the neural processing of food cues based on weight status.

Impact of isolated aerobic exercise in obese adolescents: systematic review

The juvenile obesity is currently one of the most serious public health problems. Changes in lifestyle, involving a combination of diet and physical activity, are essential elements in the management of obesity. However, it has been suggested that the prevention and treatment should emphasize the increase of physical activity rather than dietary treatments. To present the best available evidence from the controlled randomized studies to screen the impact of isolated aerobic exercise on cardiovascular and metabolic parameters in obese adolescents. Methods: Systematic review according to the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Were included randomized and controlled clinical trials of electronic databases: MEDLINE (via OvidSP), LILACS, and SciELO. Results: Four articles were identified, showing improvement in anthropometric measures, lipid and glycemic profiles. One of the articles demonstrated improvement in the systolic blood pressure (SBP) and diastolic (DBP), the maximum oxygen uptake. Conclusions: This systematic review has provided evidence on the impact of the interventions in isolated aerobic exercise in improving cardiovascular and metabolic parameters in obese adolescent population. Only four articles were identified, and further studies with greater scientific rigor are needed to confirm the scientific evidence.

Altered gas-exchange at peak exercise in obese adolescents: implications for verification of effort during cardiopulmonary exercise testing

Cardiopulmonary exercise testing is advised ahead of exercise intervention in obese adolescents to assess medical safety of exercise and physical fitness. Optimal validity and reliability of test results are required to identify maximal exercise effort. As fat oxidation during exercise is disturbed in obese individuals, it remains an unresolved methodological issue whether the respiratory gas exchange ratio (RER) is a valid marker for maximal effort during exercise testing in this population. RER during maximal exercise testing (RERpeak), and RER trajectories, was compared between obese and lean adolescents and relationships between RERpeak, RER slope and subject characteristics (age, gender, Body Mass Index [BMI], Tanner stage, physical activity level) were explored. Thirty-four obese (BMI: 35.1±5.1 kg/m²) and 18 lean (BMI: 18.8±1.9 kg/m²) adolescents (aged 12-18 years) performed a maximal cardiopulmonary exercise test on bike, with comparison of oxygen uptake (VO2), heart rate (HR), expiratory volume (VE), carbon dioxide output (VCO2), and cycling power output (W). RERpeak (1.09±0.06 vs. 1.14±0.06 in obese vs. lean adolescents, respectively) and RER slope (0.03±0.01 vs. 0.05±0.01 per 10% increase in VO2, in obese vs. lean adolescents, respectively) was significantly lower in obese adolescents, and independently related to BMI (P<0.05). Adjusted for HRpeak and VEpeak, RERpeak and RER slope remained significantly lower in obese adolescents (P<0.05). RER trajectories (in relation to %VO2peak and %Wpeak) were significantly different between groups (P<0.001). RERpeak is significantly lowered in obese adolescents. This may have important methodological implications for cardiopulmonary exercise testing in this population.

Sex Differences in Pulmonary Oxygen Uptake Kinetics in Obese Adolescents

To determine whether sex differences exist in the pulmonary oxygen uptake (VO2) uptake on-kinetic response to moderate exercise in obese adolescents. We also examined whether a relationship existed between the VO2 on-transient response to moderate intensity exercise, steady-state VO2, and peak VO2 between obese male and female adolescents. Male (n = 12) and female (n = 28) adolescents completed a graded exercise test to exhaustion on a treadmill. Data from the initial 4 minutes of treadmill walking were used to determine the time constant. The time constant was significantly different (P = .001) between obese male and female adolescents (15.17 ± 8.45 seconds vs 23.07 ± 8.91 seconds, respectively). No significant relationships were observed between the time constant and variables of interest in either sex. Sex differences exist in VO2 uptake on-kinetics during moderate exercise in obese adolescents, indicating an enhanced potential for male subjects to deliver and/or use oxygen. It may be advantageous for female subjects to engage in a longer warm-up period before the initiation of an exercise regimen to prevent an early termination of the exercise session.

Exercise training improves breathing strategy and performance during the six-minute walk test in obese adolescents

ObjectivesWe aimed to examine ventilatory responses during the six-minute walk test in healthy-weight and obese adolescents before and after exercise training. MethodsTwenty obese adolescents (OB) (age: 14.5±1.7 years; BMI: 34.0±4.7kg·m−2) and 20 age and gender-matched healthy-weight adolescents (HW) (age: 15.5±1.5 years; BMI: 19.9±1.4kg·m−2) completed six-minute walk test during which breath-by-breath gas analysis and expiratory flow limitation (expFL) were measured. OB participated in a 12-week exercise-training program. ResultsComparison between HW and OB participants showed lower distance achieved during the 6MWT in OB (−111.0m, 95%CI: −160.1 to 62.0, p<0.05) and exertional breathlessness was greater (+0.78 a.u., 95%CI: 0.091–3.27, p=0.039) when compared with HW. Obese adolescents breathed at lower lung volumes, as evidenced by lower end expiratory and end inspiratory lung volumes during exercise (p<0.05). Prevalence of expFL (8 OB vs 2 HW, p=0.028) and mean expFL (14.9±21.9 vs 5.32±14.6% VT, p=0.043, in OB and HW) were greater in OB.After exercise training, mean increase in the distance achieved during the 6MWT was 64.5 meters (95%CI: 28.1–100.9, p=0.014) and mean decrease in exertional breathlessness was 1.62 (95%CI: 0.47–2.71, p=0.05). Obese adolescents breathed at higher lung volumes, as evidenced by the increase in end inspiratory lung volume from rest to 6-min exercise (9.9±13.4 vs 20.0±13.6%TLC, p<0.05). Improved performance was associated with improved change in end inspiratory lung volume from rest to 6-min exercise (r=0.65, p=0.025). ConclusionOur results suggest that exercise training can improve breathing strategy during submaximal exercise in obese adolescents and that this increase is associated with greater exercise performance.

Effect of exercise test on pulmonary function of obese adolescents

Objectiveto investigate the pulmonary response to exercise of non-morbidly obese adolescents, considering the gender. Methodsa prospective cross-sectional study was conducted with 92 adolescents (47 obese and 45 eutrophic), divided in four groups according to obesity and gender. Anthropometric parameters, pulmonary function (spirometry and oxygen saturation [SatO2]), heart rate (HR), blood pressure (BP), respiratory rate (RR), and respiratory muscle strength were measured. Pulmonary function parameters were measured before, during, and after the exercise test. ResultsBP and HR were higher in obese individuals during the exercise test (p = 0.0001). SatO2 values decreased during exercise in obese adolescents (p = 0.0001). Obese males had higher levels of maximum inspiratory and expiratory pressures (p = 0.0002) when compared to obese and eutrophic females. Obese males showed lower values of maximum voluntary ventilation, forced vital capacity, and forced expiratory volume in the first second when compared to eutrophic males, before and after exercise (p = 0.0005). Obese females had greater inspiratory capacity compared to eutrophic females (p = 0.0001). Expiratory reserve volume was lower in obese subjects when compared to controls (p ≤ 0.05). Conclusionobese adolescents presented changes in pulmonary function at rest and these changes remained present during exercise. The spirometric and cardiorespiratory values were different in the four study groups. The present data demonstrated that, in spite of differences in lung growth, the model of fat distribution alters pulmonary function differently in obese female and male adolescents.

The Feasibility of High-Intensity Interval Exercise in Obese Adolescents

Exercise is a critical component in the management of pediatric obesity. Currently, continuous aerobic exercise (AE) is the standard of care for pediatric weight management programs. The 2008 Physical Activity Guidelines for Americans primarily promote aerobic activity for children, and aerobic-based exercise at a steady intensity (AE) is typically prescribed in pediatric weight management programs1. Several studies in adults, however, show advantages of high-intensity interval exercise (HIIE) over continuous A Eat improving fitness and health in both healthy and obese people2–4. These benefits of HIIE compared to AE have also been demonstrated in some limited studies in children. In a sample of healthy prepubescent children, Borel et al showed the immediate effects on oxygen uptake (VO2) of HIIE to be comparable to continuous AE by continuously monitoring gas exchange of subjects at various points in an exercise protocol Farpour et al showed improved health and fitness measures in healthy children as a result of HIIE5,6. Some of this work in children extends into the obese population. Ingul et al showed that impaired cardiac function in obese adolescents can be improved by 3 months of HIIE training on a treadmill twice a week for 13 weeks7. Tjonna et al studied obese adolescents in twice weekly HIIE intervention for 12 weeks compared to subjects receiving bimonthly education from multidisciplinary health professionals8. HIIE was superior to educational classes at improving subject BMI, body fat, blood pressure, blood glucose, and endothelial function. A study from the Sao Paulo School of Medicine compared HIIE and AE in obese 8–12 year old children with treadmill training protocols twice a week for 12 weeks. Both were found to be equally effective in improving aerobic fitness, insulin sensitivity, and BMI in obese children but the study may have had too few enrolled to show a difference between modes of exercise9. While these few studies of HIIE in obese children have shown benefits on fitness and cardiovascular risk factors, the acceptability and enjoyment of this protocol in children is not clear. Enjoyment of the exercise is a crucial component if our goal is long-term adherence. Another limitation of many HIIE studies in children is restriction of the interval training to treadmill protocols; a more varied exercise protocol would be more comparable to the current standard of care, which includes group games and more variable equipment choices. The purpose of this HIIE study was to measure the enjoyment and acceptability of HIIE as well as the feasibility of a multimodal protocol in obese teenagers enrolled in a multi-disciplinary pediatric weight management program as a precursor for a larger, definitive study.

Effect of Aerobic Exercise on Protein Expression in Muscle of Obese Mexican Adolescents: A Proteomic and Bioinformatic Analysis

The beneficial effects of exercise have been recognized for many years yet the molecular mechan- isms by which exercise show benefits on health are still elusive. A combination of experimental and bioinformatics approaches can be an invaluable tool to increase the cellular understanding of the molecular mechanisms that underlie the aerobic exercise in obese adolescents. Muscle skelet- al proteins were separated by 2D-PAGE and changes in protein expression were revealed by Im- ageMaster 2D Platinum analysis software. Proteins with expression changes after aerobic exercise were identified by comparison with 2D maps from SWISS-2DPAGE and interactions of proteins were analyzed with STRING and DAVID databases. After aerobic exercise, all participants de- creased glucose, insulin, total cholesterol, body mass index and waist circumference. Proteomic differential analysis revealed 10 overexpressed proteins after aerobic training, which correspond to carbonic anhydrase III, beta enolase, creatine kinase, ATP synthase beta subunit, aldolase A, glyceraldehyde-3-phosphate dehydrogenase, triosephosphate isomerase, pyruvate kinase, lactate dehydrogenase and adenylate kinase. Exercise increased glycolysis and oxidative phosphorylation pathways, which is likely to be regulated by ubiquitin c protein. In conclusion, our analysis sug- gested that obese adolescents show changes in their body mass index, waist circumference and serum glucose after aerobic exercise through improved protein expression patterns that aid, es- pecially, glucose metabolism and increase the oxidative phosphorylation. The most likely expla- nation for the observed pattern is that ubiquitin c protein keeps the glycolytic enzymes bound * Corresponding author.

Effect of exercise test on pulmonary function of obese adolescents

Objectiveto investigate the pulmonary response to exercise of non-morbidly obese adolescents, considering the gender. Methodsa prospective cross-sectional study was conducted with 92 adolescents (47 obese and 45 eutrophic), divided in four groups according to obesity and gender. Anthropometric parameters, pulmonary function (spirometry and oxygen saturation [SatO2]), heart rate (HR), blood pressure (BP), respiratory rate (RR), and respiratory muscle strength were measured. Pulmonary function parameters were measured before, during, and after the exercise test. ResultsBP and HR were higher in obese individuals during the exercise test (p = 0.0001). SatO2 values decreased during exercise in obese adolescents (p = 0.0001). Obese males had higher levels of maximum inspiratory and expiratory pressures (p = 0.0002) when compared to obese and eutrophic females. Obese males showed lower values of maximum voluntary ventilation, forced vital capacity, and forced expiratory volume in the first second when compared to eutrophic males, before and after exercise (p = 0.0005). Obese females had greater inspiratory capacity compared to eutrophic females (p = 0.0001). Expiratory reserve volume was lower in obese subjects when compared to controls (p ≤ 0,05). Conclusionobese adolescents presented changes in pulmonary function at rest and these changes remained present during exercise. The spirometric and cardiorespiratory values were different in the four study groups. The present data demonstrated that, in spite of differences in lung growth, the model of fat distribution alters pulmonary function differently in obese female and male adolescents.

Effects of 12 weeks resistance band exercise in obese adolescents on blood lipids and inflammatory markers.

Effects of 12 weeks resistance band exercise in obese adolescents on blood lipids and inflammatory markers.

A Review of Resistance Exercise Training in Obese Adolescents

Resistance training–also known as strength or weight training–has been well recognized by several national organizations as a safe and beneficial exercise modality for the health and well-being of children and adolescents. Resistance exercise improves muscular strength and can improve body composition (eg, increase lean body mass and decrease percent body fat) provided that a sufficient exercise stimulus is prescribed. Effects of resistance exercise training on body composition and metabolic profile are well established in obese adults, but warrant further investigation in obese youth. This article reviews the rationale for including a resistance training component with interventions geared toward overweight and obese adolescents by discussing the effects on various health measures. Shortcomings in published trials, including small, ethnic minority samples of short-duration and low-frequency exercise sessions primarily conducted in prepubertal youth (rather than postpubertal adolescents) limit the generalizability of the published literature on the effectiveness of resistance exercise in obese adolescents.

Metabolic responses to submaximal treadmill walking and cycle ergometer pedalling in obese adolescents

Physical activity is essential in obesity management because of the impact of exercise-related energy expenditure (EE) and fat oxidation (Fox) rate on a daily balance, but the specific physiological effects of different exercise modalities are scarcely known in obese individuals. The objective of the study was to compare the metabolic responses to treadmill (TM) and cycle ergometer (CE) exercise in obese adolescents. Gas exchange, heart rate (HR), blood lactate (LA) concentration, EE and Fox were determined at different intensity levels (up to about 85% of maximal oxygen uptake) during TM and CE in 14 pubertal (Tanner stage: >3) obese (BMI SDS: 2.15-3.86) male adolescents (age: 13-18 years). At comparable HR, oxygen uptake, EE and Fox were higher, and LA lower, during TM than CE (P<0.05-0.001), suggesting that cycling imposes a metabolic involvement at the level of the single active muscles greater than walking. Therefore, due to different physiological responses to TM and CE, walking was more convenient than cycling in obese adolescents, permitting to attain the same EE at lower HR, with lower blood LA concentration and with greater Fox. These conclusions seem clinically relevant when using exercise as a part of multidisciplinary treatment for juvenile obesity and amelioration of related metabolic disturbances.

Gas Exchange Kinetics During Exercise in Obese Adolescents. Inferences on Exercise Tolerance and Prescription.

Gas Exchange Kinetics During Exercise in Obese Adolescents. Inferences on Exercise Tolerance and Prescription.

Fat oxidation rate during and after a low- or high-intensity exercise in severely obese Caucasian adolescents

The objective is to study the effects of low-intensity (LI) or high-intensity (HI) equicaloric exercises on energy expenditure (EE) and substrate oxidation rate during and after the exercises in severely obese Caucasian adolescents. Twenty obese boys (BMI-SDS 3.04 +/- 0.52, %Fat Mass 38.2 +/- 2.1%) aged 14-16 years (pubertal stage >3) participated in this study. Maximal oxygen uptake (V'O(2max)) and maximal fat oxidation rate were determined with indirect calorimetry using a graded exercise test on a treadmill. EE and substrate oxidation rate during equicaloric low-intensity (LI, 42% V'O(2max) for 45 min) and high-intensity (HI, 67% V'O(2max) for 30 min) exercises on a treadmill and during post-exercise recovery period (60 min) were determined with indirect calorimetry. Maximal fat oxidation rate was observed at 42 +/- 6% V'O(2max) (62 +/- 5% HR(max)) and fat oxidation rate was 0.45 +/- 0.07 g/min. The total amounts of EE, during the LI and HI exercises, and the post-exercise recovery periods were not significantly different (1,884 +/- 250 vs. 1,973 +/- 201 kJ, p = 0.453), but the total amount of fat oxidised was significantly higher (+9.9 g, +55.7%, p < 0.001) during the LI exercise than during the HI exercise. However, fat oxidation rates during the post-exercise recovery periods were not significantly different following LI and HI exercises. Total fat oxidised was significantly higher during the LI than during the HI exercise in obese adolescents. However, the equicaloric exercise intensity did not influence EE, fat and carbohydrate oxidation rate during the recovery period.

Participation in organized weekly physical exercise in obese adolescents reduced daily physical activity

The aim of this study was to describe the impact of organized weekly exercise for 13 weeks on aerobic fitness, objectively assessed habitual physical activity and body weight in obese adolescents. After inclusion and diagnostic evaluation, the adolescents were randomized to either an exercise group or to a control group which lasted for 13 weeks and consisted of a variety of group exercise activities. Out of 47 adolescents 31 (66%) could be evaluated, 16 in the exercise group and 15 in the control group. After the intervention, the exercise group had decreased the daily time spent in moderate activity by 17 (32) min/day (p < 0.05), and the average intensity by 60 (96) counts/min (p < 0.05). A tendency for increased time spent in inactivity was found (37 min/day). No differences were seen in the control group for any of the variables measured. The exercise group showed, in contrast to expectations, a reduction in total daily physical activity with organized physical exercise compared to the control group. This may partly explain the failure of many intervention trials.

Participation in organized weekly physical exercise in obese adolescents reduced daily physical activity

Participation in organized weekly physical exercise in obese adolescents reduced daily physical activity