چکیده (انگلیسی):

The decrease in the performance of athlete is often associated with an imbalance between workload and recovery period. Thus, it is very important to implement tools which can assist in the quantifying the effects of workloads, so that the maximum performance of the athlete is reached. In this context, we know little about the influence of selective load periodization system (SLPS) on cardiac autonomic control and the effects on stress markers already known. Thus, the aim of this study was to investigate if the application of SLPS promoted alterations in autonomic modulation of heart rate variability (HRV), as well as same stress markers. Therefore, sixteen male basketball players (mean ± SE: age 23.3 ± 1.0 years; mass 87.5 ± 3.5 kg; height 194  2 cm) were submitted to SLPS and evaluated before and after a competition period. The HRV was evaluated by a spectral analysis of the time series composed of R-R intervals obtained in the supine position and during a tilt test. The evaluation of stress markers consisted of measuring plasma catecholamines, cortisol and free testosterone. The results demonstrated that the training load used during the competition period did not cause significant changes in the autonomic modulation of HRV. This affirmation is supported by the absence of change in oscillations of low frequency (LF: 0,04-0,15Hz), that corresponding to sympathetic and parasympathetic modulations, and high frequency (HF:0,15-05Hz), that corresponding only to parasympathetic modulations of HRV. Additionally, no changes were observed in plasma concentrations of catecholamines, free testosterone, cortisol and, consequently, in testosterone/cortisol ratio, when pre-competition and post-competition values were compared. In summary, our findings suggest that the use of SLPS in basketball athletes presented balance between workloads and recovery periods. However, further investigations are needed, including in other sports, so that we can evaluate the effects of SLPS on cardiac autonomic modulation and stress markers evaluated in this study.