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Purpose: Soccer is one of the most popular sports worldwide, a physical activity of great physiological demand and complexity. Currently, numerous trials involving physiological responses such as hypertrophy, energy expenditure, vasodilation, cardiac output, VO2max, and recovery have supported the possibility of genomic predictors' affecting performance. In a complementary way to association studies with single nucleotide polymorphisms (SNPs), the objective was to evaluate if the use of population genetics data from human-genomics databases can provide information for a better understanding of the relationship between heritability and sport performance. Methods: The study included 25 healthy male professional soccer players (25.5 [4.3] y, 177.4 [6.4] cm, 76.4 [6.4] kg, body fat 10.5% [4.3%]) from the Brazilian first-division soccer club. Anthropometric measurements and field and isokinetic tests were performed to evaluate performance and physiologic parameters of subjects. Moreover, 10 genetic polymorphisms previously related to performance were genotyped. The genotypes of the same polymorphisms were obtained for 2504 individuals from the populations deposited in the 1000 Genomes database. A principal-component analysis and matrix genetic-distances approach (Fst) were evaluated. Results: As expected, the admixture Brazilian population has numerous genetic similarities with the European and American populations from genomic databases. Although the African component is absolutely recognized in genomes from the Brazilian population, using the specific performance-related SNPs, surprisingly the African population was one of the most genetically distant of the players (P < .00001). Conclusions: The early results suggest a selective pressure on genes of elite soccer players, possibly related simultaneously to physical-performance, environmental, cognitive, and sociocultural aspects.

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Many studies have used the heart rate deflection points (HRDPs) during incremental exercise tests, because of their strong correlation with the anaerobic threshold. The aim of this study was to evaluate the profile of the HRDPs identified by a computerized method and compare them with ventilatory and lactate thresholds. Twenty-four professional soccer players (age, 22 ± 5 years; body mass, 74 ± 7 kg; height 177 ± 7 cm) volunteered for the study. The subjects completed a Bruce-protocol incremental treadmill exercise test to volitional fatigue. Heart rate (HR) and alveolar gas exchange were recorded continuously at ≥1 Hz during exercise testing. Subsequently, the time course of the HR was fit by a computer algorithm, and a set of lines yielding the lowest pooled residual sum of squares was chosen as the best fit. This procedure defined 2 HRDPs (HRDP1 and HRDP2). The HR break points averaged 43.9 ± 5.9 and 89.7 ± 7.5% of the VO2peak. The HRDP1 showed a poor correlation with ventilatory threshold (VT; r = 0.50), but HRDP2 was highly correlated to the respiratory compensation (RC) point (r = 0.98). Neither HRDP1 nor HRDP2 was correlated with LT1 (at VO2 = 2.26 ± 0.72 L·min(-1); r = 0.26) or LT2 (2.79 ± 0.59 L·min(-1); r = 0.49), respectively. LT1 and LT2 also were not well correlated with VT (2.93 ± 0.68 L·min(-1); r = 0.20) or RC (3.82 ± 0.60 L·min(-1); r = 0.58), respectively. Although the HR deflection points were not correlated to LT, HRDP2 could be identified in all the subjects and was strongly correlated with RC, consistent with a relationship to cardiorespiratory fatigue and endurance performance.

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1. The aim of the present study was to investigate the cardiovascular effects of anabolic androgenic steroid (AAS) abuse by comparing the electrocardiographic parameters before and after submaximal exercise between AAS users and non-AAS users. 2. A total of 22 men who regularly engaged in both resistance and aerobic exercise at fitness academies volunteered for the study (control group: n = 11, age 25 ± 4 years; AAS group: n = 11, age 27 ± 5 years). All subjects were submitted to submaximal exercise testing using an Astrand-Rhyming protocol. Heart rate and electrocardiography parameters were measured at rest and at the third minute of the post-exercise recovery time. 3. AAS users presented higher QTc and QTd at rest (10% and 55%, respectively) and at the post-exercise period (17% and 43%, respectively), compared with control subjects. The maximal and minimum QTc interval of the AAS group was significantly prolonged at the post-exercise period (12% and 15%, respectively). The haemodynamic parameters were similar in both groups (P > 0.05). The AAS group showed a lower heart rate recovery at the first minute after the test (P = 0.0001), and a higher exertion score (P < 0.0001) at a lower workload, compared with the control group. 4. Our results show that the QTc interval and dispersion are increased in individuals who abuse AAS, suggesting the presence of ventricular repolarization abnormalities that could potentially increase the risk of cardiac arrhythmias and sudden cardiac death.

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The purpose of this study was to investigate the cardiovascular effects of anabolic androgenic steroid (AAS) use, specifically the hemodynamic response, during maximal treadmill exercise testing by comparing the exercise response between users of AAS (U-AAS) and non-AAS users (N-AAS). Twenty-four men (n=12; 29+/-3.4 years and n=12; 29.5+/-8.2 years for the U-AAS and N-AAS groups, respectively) with regular participation in both resistance (mean=6 d.wk) and aerobic exercise (mean=2 d.wk) volunteered for the study. Both groups of subjects completed a ramp-protocol maximal treadmill exercise test to volitional fatigue. Several hemodynamic and metabolic measures were obtained before, during, and after testing. The results demonstrate for the first time that chronic administration of high doses of AAS (355.4+/-59.47 mg.wk) lead to hemodynamic and metabolic response impairment. In conclusion, the chronotropic significant incompetence in the current study was reflected by an exaggerated hemodynamic response to exercise. Furthermore, the findings suggest that nonusers of AAS showed increases in VO2max when compared to the AAS group. Therefore, this study provides a contraindication to AAS use, especially in those at increased risk of cardiovascular events.

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O objetivo deste estudo foi investigar a resposta hormonal aguda ao treinamento de força em diferentes ordens de exercícios. Dez homens treinados (22,4 ± 2,7 anos; 80,3 ± 5,7 kg; 180 ± 8 cm; 21,5 ± 0,3 kg.m-2) participaram do estudo e completaram dois protocolos experimentais com diferentes ordenações de exercícios. As sequências foram compostas de três séries para cada exercício usando 70% de 1RM, com dois minutos de intervalo de descanso entre séries e exercícios com intervalo de sete dias entre elas. A ordem dos exercícios para SEQA foram: supino reto (SR), puxada no pulley pela frente (PF), desenvolvimento (DES), rosca direta (RD) e tríceps no pulley (TP). A ordem dos exercícios para SEQB foram TP, RD, DES, PF e SR. As variáveis sanguíneas analisados foram hormônio de crescimento (GH) e cortisol pré e imediamente pós-esforço a execução da sessão de treinamento. Os resultados demonstram que a SEQA promoveu maior e significativo aumento na concentração do GH imediatamente após a sessão, quando comparado a SEQB. A concentração de cortisol apresentou um aumento significativo quando comparado os momentos pré e pós para ambas as sequências. No entanto, não houve diferença estatisticamente significativa quando feita a comparação entre as sequências. Portanto, parece que a ordem dos exercícios pode influenciar as respostas do GH sendo que exercícios para grandes grupos musculares promovem um aumento significativo deste hormônio do que exercícios para pequenos grupos musculares no início da sessão.

The aim of this study was to investigate the acute hormonal response to resistance training sessions with different exercises order in men. Ten recreationally trained men (22.4 ± 2.7 years; 80.3 ± 5.7 kg; 180 ± 8 cm; 21.5 ± 0.3 kg.m-2) participated in the study. All subjects completed two experimental protocols with different exercises order. The exercise sequences were composed by three sets using 70%of 1RM for each exercise with 2 minutes rest between sets and exercises and separated by seven days between them. Exercise order for SEQA was bench press (BP), lat-pull down (LPD), seated shoulder press(SP), biceps curl (BC) and tríceps extension (TE). The exercises order for SEQB order were TE, BC, SP,LPD and BP. The blood variables analyzed were: growth hormone (GH), cortisol before (Pre) and immediately after (Post) each exercise session. The results shown that SEQA promoted higher and significantly increases in GH concentration immediately post session, as compared with SEQB. The cortisol concentration presented a significantly increase when compared pre and post moments for both sequences. However, there were not statistically differences when compared SEQA and SEQB post session. In conclusion, seems that exercises order can influences the GH responses, being exercises for large muscle group promoted a significantly increase in this hormone than exercises for small muscle group at the beginning of training session.

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