Health markers in obese adolescents improved by a

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Health markers in obese adolescents improved by a 12-week recreational soccer program: a randomised controlled trial ab

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Fabrício Vasconcellos , Andre Seabra , Felipe Cunha , Rafael Montenegro , Jociene Penha , d

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Eliete Bouskela , José Firmino Nogueira Neto , Paulo Collett-Solberg & Paulo Farinatti

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Research Centre in Education, Innovation, and Intervention in Sports, Sports Faculty, University of Oporto, Oporto, Portugal b

Laboratory of Physical Activity and Health Promotion, Institute of Physical Education and Sports, University of Rio de Janeiro State, Rio de Janeiro, Brazil c

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Research Centre in Physical Activity, Health and Leisure (CIAFEL), Sports Faculty, University of Oporto, Oporto, Portugal d

Laboratory of Clinical and Experimental Research in Vascular Biology, Biomedical Center, University of Rio de Janeiro State, Rio de Janeiro, Brazil e

Medical Sciences Graduate Program, Faculty of Medical Sciences, University of Rio de Janeiro State, Rio de Janeiro, Brazil f

Physical Activity Sciences Graduate Program, Salgado de Oliveira University, Niteroi, Brazil Published online: 24 Jul 2015.

To cite this article: Fabrício Vasconcellos, Andre Seabra, Felipe Cunha, Rafael Montenegro, Jociene Penha, Eliete Bouskela, José Firmino Nogueira Neto, Paulo Collett-Solberg & Paulo Farinatti (2015): Health markers in obese adolescents improved by a 12-week recreational soccer program: a randomised controlled trial, Journal of Sports Sciences, DOI: 10.1080/02640414.2015.1064150 To link to this article: http://dx.doi.org/10.1080/02640414.2015.1064150

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Journal of Sports Sciences, 2015 http://dx.doi.org/10.1080/02640414.2015.1064150

Health markers in obese adolescents improved by a 12-week recreational soccer program: a randomised controlled trial

FABRÍCIO VASCONCELLOS1,2, ANDRE SEABRA3, FELIPE CUNHA2, RAFAEL MONTENEGRO2, JOCIENE PENHA4, ELIETE BOUSKELA4, JOSÉ FIRMINO NOGUEIRA NETO5, PAULO COLLETT-SOLBERG4 & PAULO FARINATTI2,6

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Research Centre in Education, Innovation, and Intervention in Sports, Sports Faculty, University of Oporto, Oporto, Portugal, 2Laboratory of Physical Activity and Health Promotion, Institute of Physical Education and Sports, University of Rio de Janeiro State, Rio de Janeiro, Brazil, 3Research Centre in Physical Activity, Health and Leisure (CIAFEL), Sports Faculty, University of Oporto, Oporto, Portugal, 4Laboratory of Clinical and Experimental Research in Vascular Biology, Biomedical Center, University of Rio de Janeiro State, Rio de Janeiro, Brazil, 5Medical Sciences Graduate Program, Faculty of Medical Sciences, University of Rio de Janeiro State, Rio de Janeiro, Brazil and 6Physical Activity Sciences Graduate Program, Salgado de Oliveira University, Niteroi, Brazil (Accepted 9 June 2015)

Abstract The effects of a recreational soccer program (RSP) upon body composition, heart rate variability (HRV), biochemical markers, cardio-respiratory fitness, and endothelial function in obese adolescents were investigated. A randomised controlled clinical trial was conducted with 30 adolescents aged 12–17 years and body mass index (BMI) >2 standard deviations of WHO reference values, which were assigned to RSP (n = 10, 2 girls) and obese control (n = 10, 4 girls) groups. The 12-week RSP included 60-min sessions performed 3 times/week. BMI, waist circumference, blood pressure, blood glucose, lipid profile, insulin, C-reactive protein, HRV, and maximal oxygen consumption (VO2peak) were evaluated following standardised procedures. Body composition was determined by dual-energy X-ray absorptiometry and endothelial function by venous occlusion plethysmography. After intervention, RSP exhibited significant reductions in BMI (−0.7 ± 0.2 kg · m–2), waist circumference (−8.2 ± 1.4 cm), %body fat (−2.2 ± 0.4%), systolic blood pressure (−5.0 ± 2.3 mmHg), total cholesterol (−16.2 ± 5.8 mg · dL−1), triglycerides (−20.5 ± 12.9 mg · dL−1), C-reactive protein (−0.06 ± 0.01 mg · dL−1), insulin resistance (HOMA-IR, −1.4 ± 0.6), and sympathetic activity (LF, −13.9 ± 6.6 un) vs. controls (P < 0.05). Significant increase was observed in parasympathetic activity (HF, 13.9 ± 6.6 un), VO2peak (7.9 ± 2.8 ml · kg−1 · min−1), and high-density lipoprotein cholesterol (11.0 ± 6.3 mg · dL−1) (P < 0.05). Vascular conductance (19.5 ± 8.1 ml · min−1 · 100 ml, P = 0.005) increased and vascular resistance (−5.9 ± 2.4 ml · min−1 · 100 ml, P = 0.041) decreased in RSP, but not in controls. A 12-week recreational soccer intervention was effective to improve biochemical, cardiovascular, and fitness health markers in obese adolescents. Keywords: body composition, cardiorespiratory fitness, inflammatory markers, sports, exercise, health

Introduction The prevalence of obesity in adolescence has increased worldwide (Saha, Sarkar, & Chatterjee, 2011), and this has become a major public health concern (Swinburn, Gill, & Kumanyika, 2005). Obesity during childhood may influence the genesis and progression of atherosclerosis in adult life, being related to cardiometabolic comorbidities such as hyperinsulinemia, glucose intolerance, hypertension, and dyslipidemia (Swinburn et al., 2005).

Team sports have been considered a strategy to prevent overweight and obesity, as well as to improve cardiovascular risk in adults (Reilly & Kelly, 2011). However, less evidence is available with regard to this kind of intervention in obese adolescents (Hills, Andersen, & Byrne, 2011). It must be acknowledged that traditional physical activity (PA) programs, such as cycling and running, are more easily performed when individualised routines are prescribed. However, obese adolescents are not always motivated by these types of exercise (Krustrup, Aagaard, et al., 2010), and low

Correspondence: Paulo Farinatti, Laboratory of Physical Activity and Health Promotion, Institute of Physical Education and Sports, University of Rio de Janeiro State, Rio de Janeiro, Brazil. E-mail: [email protected] © 2015 Taylor & Francis


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adherence evidently makes any PA intervention innocuous. In this context, team sports seems to be a good alternative to increase PA participation among adolescents (Krustrup, Aagaard, et al., 2010), since they appear to be more interested in sports activities that are social, outdoors, and competitive (Drake et al., 2012). However, data about the beneficial effects of recreational team sports participation upon health markers in obese adolescents are scarce (Vasconcellos et al., 2014). Soccer is one of the most popular team sports, and previous studies have shown that its practice can improve health markers in adults (Krustrup, Aagaard, et al., 2010; Krustrup, Hansen, et al., 2010). Nevertheless, few studies have investigated the effects of recreational soccer on cardiovascular risk markers in adolescents. Furthermore, most of the available research applied programs not exclusively based on soccer practice (Calcaterra et al., 2013; Madsen, Thompson, Adkins, & Crawford, 2013; Park et al., 2012) or evaluated very restricted markers of cardiovascular risk (Sacheck et al., 2011). In brief, research is lacking about the effectiveness of soccer programs adapted to obese adolescents upon health markers. Hence, the purpose of this randomised controlled trial was to investigate the impact of a 12-week recreational soccer program (RSP) upon the body composition, biochemical risk markers for cardiovascular disease, cardiorespiratory fitness, cardiac autonomic activity, and endothelial function in obese adolescents.

Figure 1. Study design overview.

Methods and procedures Study design A randomised controlled clinical trial was conducted with 30 adolescents (20 obese and 10 non-obese) over 12 weeks. The study protocol was approved by institutional ethics committee (CEFADE 12/2013), and all parents or legal guardians signed informed consent providing authorisation for the children to participate in the study. The clinical trial has been registered at a WHO accredited office (Thai Clinical Trials Registry, protocol TCTR20150512001). Computer-generated randomisation sequence and preparation of envelopes containing the group allocations was performed by a researcher blind for the purposes of the study. Pre- and posttesting and data analysis were performed in a single blind fashion, the evaluators not knowing to what group subjects were assigned. However, due to the nature of the intervention, training sessions were ministered by personnel involved with the study. Figure 1 provides an overview of the study protocol. Eligibility criteria for participants To be eligible for participation in the study, participants should be within 12- to 17-year-old, to exhibit a BMI >2 standard deviations above age- and sexspecific WHO reference medians (de Onis et al., 2007) and to be in the later stages of pubertal maturation (pubic hair stage 4 and 5). Exclusion

Health markers in obese adolescents and recreational soccer program criteria included medical conditions contraindicating the participation in physical activities, the use of medication influencing the observed outcomes, and participation in structured exercise, nutrition, or weight loss programs, within 6 months prior to the initial screening.

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means of a computer generated table of random numbers. As aforementioned, participants’ information was blindly placed in consecutively numbered opaque envelopes according to the randomised sequence. Allocation of participants in either experimental or control groups was then made by drawing the envelopes in a counter-balanced order.


Recruitment of participants Participants were recruited among adolescents attended by the Nucleus for Studies on Adolescent Health of the University of Rio de Janeiro State (NSAH), Brazil, where they were provided systematically medical, psychological, and nutritional assistance. The recruitment period was 1 June to 30 August 2013. From the initially randomised 51 adolescents, a sample of 32 obese adolescents qualified for the study (10 girls) (mean±SD; age = 14.5 ± 1.6 years), which were subsequently randomly assigned to experimental and non-exercise control groups. For ethical reasons, those assigned as controls were invited at the end of the experiment to enrol in the RSP program. Six adolescents in each group dropped off the study for reasons not related to the soccer program. Therefore, 10 adolescents (2 girls, age = 14.1 ± 1.1 years, BMI = 30.3 ± 4.6 kg · m–2) completed the soccer intervention and other 10 (4 girls, age = 14.8 ± 1.4 years, BMI = 32.2 ± 4.9 kg · m–2) composed the obese control group. A third group of 10 non-obese adolescents (3 girls, age = 14.6 ± 1.6 years, BMI = 19.4 ± 10.6 kg · m–2) was also randomly selected from NSAH and evaluated only at baseline, exclusively in order to provide reference values to evaluate possible cardiac autonomic and endothelial dysfunction, as well as the effects of RSP upon these markers in the obese group. Baseline and post-intervention testing occurred at the Nucleus for Studies on Adolescent Health of the University of Rio de Janeiro State (NSAH), Brazil. Assessments were done under similar conditions and at approximately the same time of the day (8.00– 9.00 am) to minimise potential diurnal variation in measured variables. Sample size calculations were performed using the GPower software 3.1.9.2 (Universität Düsseldorf, Germany) (Faul, Erdfelder, Lang, & Buchner, 2007) considering a statistical power (1 – β) of 0.8, effect size of 0.3 and P fixed at 0.05. A sample size of at least eight participants in each group was required. Randomisation The initial randomisation was performed using the individual medical registration numbers. Participants considered eligible to participate in the study according to inclusion and exclusion criteria were then allocated in either control or experimental groups by

Soccer intervention The RSP was performed three times a week during 12 weeks at the University of Rio de Janeiro State facilities from 8.30 to 9:30 am (Mondays, Wednesdays, and Fridays). Each session consisted of 10-min warm-up followed by 40 min of games performed in small pitch areas (such as 2 vs. 2, 3 vs. 3 and 4 vs. 4) and 10-min cool-down. Training intensity was recorded by portable heart rate monitors (Polar RS800cx, PolarTM, Kempele, Finland). The soccer training sessions were ministered by two certified instructors under the supervision of the principal investigator. The intervention period ranged from 1 September 2013 and 20 January 2014, ending because of school holidays. All participants were instructed not to change their regular physical activity habits during the experiment. Anthropometry, biological maturity status, and blood pressure assessment Body mass, height, hip circumference, and waist circumference (WC) were measured according to standard procedures (Lohman, 1986). Body mass was assessed with a digital scale (FilizolaTM, Sao Paulo, SP, Brazil), height with a fixed stadiometer (SannyTM, São Paulo, SP, Brazil), and waist and hip circumferences with a metal anthropometric tape. The BMI was calculated, and adolescents were classified as obese according to age-specific BMI cut-offs for boys and girls (de Onis et al., 2007). The maturation stage of pubic hair was evaluated as part of a comprehensive clinical examination by a paediatrician with previous experience in the assessment of secondary sex characteristics, according to criteria proposed by Tanner (1962) (Lazzer, Patrizi, De Col, Saezza, & Sartorio, 2014). The blood pressure was assessed by an automated Omron 705IT device (OmronTM Healthcare Co., Kyoto, Japan) according to the European Society of Hypertension recommendations (Topouchian, El Assaad, Orobinskaia, El Feghali, & Asmar, 2006). Participants remained seated in an upright position with the right arm resting on a table at heart level. The first reading was performed after a 10-min resting period. The other two readings were performed with 3-min intervals interspersed between measures.


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The mean of three blood pressure measurements was recorded as final result. According to U.S. Department of Health and Human Services (Falkner & Daniels, 2004), high blood pressure is defined as SBP and DBP above 115 and 65 for boys and 112 and 55 for girls (14 years-old on average), respectively. The same trained investigator performed all anthropometric and blood pressure measurements.

Signal Analysis Group, Department of Applied Physics, University of Kuopio, Kuopio, Finland), considering the last 5 min of recording. The sampling frequency was 1000 Hz, and signal artefacts were filtered by excluding R-R intervals with differences of more than 20% vs. the preceding R-R interval (Yamamoto, Hughson, & Peterson, 1991). The same trained investigator performed all HRV analyses.

Body composition

Biochemical markers

Fat percentage and fat-free mass were assessed by dual-energy X-ray absorptiometry (Hologic QDR 4500, HologicTM, Bedford, MA, USA). The equipment was calibrated according to manufacturer’s instructions. Participants were scanned in the supine position using standard protocols. Scans were performed in high resolution and analysed by the same trained technician. Principles underlying body composition analyses with DXA were described elsewhere (Kelly, Berger, & Richardson, 1998).

Assessments were performed before the beginning of RSP and within 48 h after the last training session. Serum was collected from centrifuged samples after which low-density lipoprotein (LDL), high-density lipoprotein (HDL), total cholesterol, and triglyceride levels were determined fluorometrically using an automatic analyser (Cobas FaraTM, Roche, Neuillysur Seine, France) and enzymatic kits (Roche DiagnosticsTM, Mannheim, Germany). The blood collected from a non-heparinised syringe was centrifuged for 2 min, after which it was pipetted and frozen at −20oC until analysed for insulin levels using an enzyme immunoassay ELISA kit (Dako CytomationTM, Cambridgeshire, UK). The C-reactive protein was assessed by Latex high sensitivity with automatic analyser (Biosystems A25 Chemistry AnalyzerTM, BioSystems, Massachusetts, USA). Oral glucose tolerance test (OGT) was performed using the first blood sample after 12-h fasting, followed by ingestion of 75 g dextrose with water and a second blood drawn after 2 h. The homeostasis model assessment for insulin resistance (HOMA-IR) was calculated as the product between fasting insulin (mU · ml–1) and fasting glucose (mmol · L–1)/22.5.

Cardio-respiratory fitness Cardiopulmonary exercise testing was performed in cycle ergometer CG-04 (InbramedTM, Porto Alegre, RS, Brazil) using a ramp-incremental protocol with initial load fixed at 25 W and increasing 10 W every minute. The VO2 was continuously measured until exhaustion using an automated open-circuit breathby-breath metabolic system (Ultima Cardio2, Medical GraphicsTM, St Louis, MI, USA). The metabolic system was calibrated before each test according to manufacturer’s instructions. The test was considered as maximal if at least three of the following four criteria were satisfied (Howley, Bassett, & Welch, 1995): (1) maximum voluntary exhaustion defined by attaining score 10 on Borg CR-10 scale; (2) 90% of predicted HRmax [220 – age] or presence of heart rate plateau (ΔHR between two consecutive work rates ≤4 bpm); (3) presence of VO2 plateau (ΔVO2 between two consecutive work rates of less than 2.1 mL·kg−1·min−1); (4) maximal respiratory exchange ratio (RERmax) >1.10. The oxygen uptake at rest (VO2rest) was measured as described elsewhere (Cunha et al., 2013). Heart rate variability (HRV) The HRV was recorded during 25 min at rest using a cardiotachometer (Polar RS800cx, PolarTM, Kempele, Finland), and 5 min windows were extracted and downloaded for analysis by specific software (Polar Precision Performance, PolarTM, Kempele, Finland). The HRV indices were analysed using the KubiosTM HRV software (Biomedical

Endothelial function assessment The endothelial function was evaluated by measuring the forearm blood flow (FBF) using venous occlusion plethysmography (VOP) (Hokanson EC6; D.E. HokansonTM Inc, Bellevue, WA) with a mercury-in-Silastic strain gauge (Kraemer-Aguiar, Maranhão, Cyrino, & Bouskela, 2010). The venous occlusion plethysmography was performed in three stages: (1) basal blood flow and basal vascular conductance; (2) blood flow after ischemia and vascular conductance after ischemia; (3) blood flow after 0.4 mg oral spray nitroprusside (NITRO – Nitrolingual BurnsAdlerM Pharmaceuticals Inc, Charlotte, NC, USA) and vascular conductance after NITRO. Measurements were performed in the morning (7:00–10:00 a.m.) after 8–10 h overnight fasting, at the supine position, in a quiet temperature-controlled room (20–22°C), and after

Health markers in obese adolescents and recreational soccer program emptying the bladder. The forearm length (medial epicondyle of humerus to ulnar styloid) and maximal circumference were measured using a flexible tape measure. To avoid underestimation of FBF, the forearm circumference was required to be 0.05). After 12 weeks of soccer practice, the RSP group showed a significant increase in parasympathetic activity [i.e. high frequency component (HF)] (P = 0.047), while HR at rest (P = 0.040) and sympathetic activity [i.e. low frequency component (LF)] (P = 0.047) decreased. These markers remained unaltered in the obese control group (P > 0.282). Moreover, differences between RSP vs. non-obese controls were no longer detected after the intervention (P > 0.196). Table III presents changes in biochemical and inflammatory markers due to RSP. Significant increase pre vs. post were found for HDL and decrease in total cholesterol, triglycerides, C-reactive protein, fasting glucose, and HOMA-IR in the intervention group compared to controls. The LDL increased significantly in the obese control, but not in RSP group. Glucose tolerance and insulin levels remained unaltered in both groups. While endothelin-1 (ET-1) and tumoral necrosis factor- α (TNF-α) significantly decreased in RSP after intervention, no significant variation was detected for the other inflammatory markers. Figure 3 presents data for endothelial function at baseline and post-intervention. At baseline, blood flow and vascular conductance after ischemia were higher in non-obese controls vs. RSP (P = 0.049) and obese controls (P = 0.047). After the 12-week intervention, most variables remained unaltered and no difference between and within-groups were detected for basal blood flow (P = 0.347), basal vascular conductance (P = 0.237), blood flow after ischemia (P = 0.562), blood flow after nitroprusside (P = 0.487), and vascular conductance after nitroprusside (P = 0.621). On the other hand, the vascular conductance increased in RSP (P = 0.050), but not in the obese control group (P = 0.472).

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Table I. Mean (SD) values for baseline anthropometric characteristics, blood pressure, cardio-respiratory fitness, heart rate variability, biochemical markers, and endothelial function in intervention and obese control groups.


Variables Anthropometric Age (years) Height (cm) Weight (kg) Body mass index (kg · m–2) Tanner stage (range) Fat percentage (%) Fat free mass (kg) Waist circumference (cm) Waist circumference/height (cm) Blood pressure Systolic blood pressure (mmHg) Diastolic blood pressure (mmHg) Mean blood pressure (mmHg) Cardiorespiratory fitness VO2 at rest (ml · kg−1 · min−1) VO2 peak (ml · kg−1 · min−1) Heart rate peak (bpm) Biochemical markers Total cholesterol (mg · dL−1) HDL (mg · dL−1) LDL (mg · dL−1) Triglycerides (mg · dL−1) C-reactive protein (mg · dL−1) Fasting glucose (mg · dL−1) Glucose tolerance (60 min) (mg · dL−1) Glucose tolerance (120 min) (mg · dL−1) Insulin (uUI · mL–1) HOMA-IR Inflammatory biomarkers Leptin (pg · ml–1) IL-6 (pg · ml–1) Resistin (ng · ml–1) TNF-α (pg · ml–1) Adiponectin (ng · ml–1) ET-1 (pg · ml–1) NEFA (mmol · l–1)

Intervention group (n = 10) mean ± SD [CI]

14.1 163.1 82.2 31.1

± ± ± ±

41.1 43.2 98.7 0.60

± ± ± ±

1.3 [11.3–16.7] 8.3 [151.1–169.9] 13.7 [61.5–98.2] 5.2 [22.8–46.1] 4–5 6.1 [30.7–55.8] 8.2 [25.8–68.3] 10 [73.2–106.9] 0.2 [0.2–0.7]

Obese control group (n = 10) mean ± SD [CI]

14.8 161.2 86.3 32.2

± ± ± ±

42.0 48.3 103.5 0.64

± ± ± ±

1.4 [12–17.1] 8.2 [152.2–169.4] 17.4 [66.8–99.8] 4.9 [23.4–48.9] 4–5 5.4 [31.3–56.6] 7.5 [21.2–76.5] 14.5 [83.9–119.3] 0.3 [0.2–0.8]

P-value

0.147 0.915 0.483 0.388 0.476 0.747 0.136 0.333 0.758

128 ± 10 [112–145] 81 ± 5 [66–99] 70 ± 5 [58–81]

128 ± 9 [111–150] 79 ± 5 [61–92] 70 ± 7 [56–83]

0.820 0.292 0.321

3.0 ± 0.6 [2.8–3.4] 25.2 ± 3.2 [20.7–31.3] 191 ± 17 [177–201]

3.6 ± 0.7 [3.1–4.1] 22.9 ± 3.1 [18.2–29.9] 187 ± 14 [178–199]

0.842 0.234 0.321

166.4 33.6 101.1 118.4 0.43 92.9 121.5 96 37.6 8.2

± ± ± ± ± ± ± ± ± ±

21.6 [132.8–239.7] 6.9 [29.5–42.3] 13.6 [89.1–123.5] 38.8 [100.9–137.2] 0.32 [0.28–0.51] 6.4 [81.9–110.1] 31.8 [100–160.2] 13.7 [71.9–111.2] 12.4 [21.3–58.5] 1.1 [5.1–12.5]

168.7 32.7 99.6 120.3 0.39 87.6 131.4 99.3 38.9 8

± ± ± ± ± ± ± ± ± ±

32.7 [100–201.1] 18.7 [22.8–51.9] 36.2 [78.1–119.1] 72.6 [101.9–151] 0.13 [0.19–0.6] 8.9 [77.1–99.3] 42.5 [99.8–172] 15.3 [82.6–126.9] 11.7 [23.1–62,2] 0.8 [4.3–13.7]

0.749 0.497 0.758 0.941 0.102 0.196 0.584 0.633 0.354 0.783

27.5 2.2 8.3 3.1 5587 2.1 0.6

± ± ± ± ± ± ±

13.2 [17.1–36] 1.7 [1.3–4.9] 4.5 [4.8–10.8] 2.1 [1.3–5.3] 1879 [2273–8932] 0.5 [1–3.9] 0.1 [0.2–0.8]

35.2 1.7 7.7 2.7 5784 1.7 0.4

± ± ± ± ± ± ±

17.8 [26.1–46.5] 0.7 [1.1–3.5] 2.7 [2.3–14.1] 1.1 [1–4.8] 2084 [2016–9983] 0.5 [0.8–4.4] 0.2 [0.1–0.9]

0.375 0.534 0.741 0.169 0.877 0.225 0.112

Note: IL-6, Interleukin-6; TNF-α, Tumoral necrosis factor-α; ET-1, Endothelin-1; NEFA, Non-esterified fatty acids; NE, Not evaluated. Pvalues refer to differences between groups; SD, standard deviation; CI, confidence interval.

Additionally, values in RSP became similar to those exhibited by the non-obese control group (P = 0.191).

Discussion The purpose of this randomised controlled trial was to investigate the impact of an RSP upon the body composition, blood pressure, cardio-respiratory fitness, cardiac autonomic activity, biochemical risk markers, and endothelial function in obese adolescents. Our findings demonstrated that recreational soccer performed three times a week during 12 weeks resulted in beneficial changes in body mass and composition, VO2peak, resting blood pressure, autonomic activity, plasma lipid and glucose profile,

C-reactive protein, and endothelial-dependent vasodilation. In the present study, DXA was used to assess changes in body composition, ratifying the results of previous studies that soccer practice might help decreasing percentage body fat (Vasconcellos et al., 2014). On the other hand, the beneficial impact of PA programs on the blood pressure of adolescents who are overweight or obese has not been extensively evaluated (Bayne-Smith et al., 2004; Kim et al., 2007). In the present study, only SBP at rest decreased by approximately 8 mmHg after RSP, which concurs with some previous trials (BayneSmith et al., 2004; Foschini et al., 2010; Meyer, Kundt, Lenschow, Schuff-Werner, & Kienast, 2006) reporting a decrease of 5–6 mmHg in SBP in similar populations after traditional aerobic training

6.7 31.3 −4.7

3.2 ± 1.7 [3–3.6] 33.1 ± 9.2 [29.7–36.3] 182 ± 14 [171–200]

0.377