The aim of this randomized controlled study was to verify the impact of a 12-weeks muscular endurance (ME) training of high repetitions (i. e., 15-30) with 2 different periodization models on body composition, maximal strength, muscular endurance and cardiorespiratory fitness. Twenty eight sedentary women aged 20-35 years were randomly assigned to: control (CON) (n=8), linear periodization (LP) (n=10) and daily undulating periodization (DUP) (n=10). LP and DUP models significantly improved body composition, maximal strength and ME. However, no significant changes were detected for cardiorespiratory fitness. LP showed a higher body fat loss (- 12.73%) compared to DUP (- 9.93%) (p=0.049), and systematically higher effect sizes (ES) when compared with DUP for maximal strength and cardiorespiratory fitness parameters (e. g. ES=0.53 for ventilatory threshold). In contrast, DUP exhibited a significantly (p=0.002) greater ME gain (129.43%) compared to LP (70.72%) in bench press, and greater ES in all exercises. It may be suggested that LP performed with a high number of repetitions may be considered an appropriate periodization model for untrained young women that would likely lead to the improvement of body composition and maximum strength performance, whereas DUP is more effective for the development of ME.

Objective: To evaluate and compare the autonomic heart rate (HR) modulation, under resting conditions in relation to body posture, in sedentary young adults. Methods: Twenty young healthy and sedentary men aged 22.6 ± 2.5 years participated in the study. The HR and R-R intervals (in ms) of the electrocardiogram (EKG) were obtained in real time using the modified DII derivation, with the volunteers at rest in the supine and sitting positions, for 15 minutes. The R-R data were analyzed in the time domain, by means of the RMSSD, RMSM and pNN50 (%) indices; and in the frequency domain, by means of spectral analysis and fast Fourier transforms (FFT), using low frequency (LF) and high frequency (HF) bands expressed as normalized units and as the LF/HF ratio. The statistical analysis consisted of the Spearman test for correlation analyses and the Wilcoxon test for paired samples, with significance of α= 5%. Results: In the time domain, the RMSSD and pNN50 indices demonstrated statistically significant differences between the supine and sitting positions (p< 0.05). The RMSM index did not showed any statistically significant difference between the positions (p> 0.05). In the frequency domain, the LF and HF bands and the LF/HF ratio demonstrated statistically significant differences between the supine and sitting positions (p< 0.05). Conclusions: The results demonstrated that, by changing the posture, autonomic adjustments were produced to the parasympathetic and sympathetic nervous systems with regard to HR control. This can be attributed to the integrity of the neurocardiac system.

Physical training has been strongly recommended as a non-pharmacological treatment for coronary artery disease (CAD). Genetic polymorphisms have been studied to understand the biological variability in response to exercise among individuals. This study aimed to verify the possible influence of apolipoprotein B (ApoB: rs1042031 and rs693) and angiotensin-converting enzyme (ACE-ID: rs1799752) genotypes on the lipid profile and functional aerobic capacity, respectively, after an aerobic interval training (AIT) program in patients with CAD and/or cardiovascular risk factors. Sixty-six men were randomized and assigned to trained group (n=32) or control group (n=34). Cardiopulmonary exercise test was performed to determine the ventilatory anaerobic threshold (VAT) from cardiorespiratory variables. The AIT program, at an intensity equivalent to %VAT (70–110%), was conducted three times a week for 16 weeks. ApoB gene polymorphisms (−12669C>T (rs1042031) and −7673G>A (rs693)) were identified by real-time polymerase chain reaction (PCR). I/D polymorphism in the ACE gene (rs1799752) was identified through PCR and fragment size analysis. After 16 weeks, low-density lipoprotein (LDL) levels increased in the trained and control groups with the GA+AA genotype (−7673G>A) of the ApoB gene. Trained groups with ACE-II and ACE-ID genotypes presented an increase in oxygen consumption (VO2VAT) and power output after the AIT program. The presence of the ACE I-allele was associated with increased aerobic functional capacity after the AIT program. Increased LDL levels were observed over time in patients with the −7673G>A polymorphism of the ApoB gene. Trial Registration Information: ClinicalTrials.gov: NCT02313831

Objective: To evaluate the influence of oral contraceptive use on lipid levels, heart rate (HR) variability and aerobic capacity among sedentary young women. Methods: The subjects were 20 healthy women (23.55±1.88 years): ten used oral contraceptives (TG) and ten did not (CG). Ergospirometric test on a cycle ergometer was used to determine the aerobic capacity at the anaerobic threshold and at the exercise peak. In addition, recordings of HR and R-R (iRR) intervals in the supine and seated positions, for 15 minutes, and biochemical blood analysis were performed. The iRR (ms) indices were analyzed in the time domain (TD) for RMSSD, RMSM and pNN50 (%), and in the frequency domain (FD) using fast Fourier transforms from low (LF) and high (HF) frequency bands in normalized units, obtaining the LF/HF ratio. Mann-Whitney and Kruskal-Wallis, with α=5%, were used for statistical analyses. Results: The triglyceride and cholesterol levels in the TG were greater than those in the CG (p<0.05). At the anaerobic threshold and at the exercise peak, the power (W), oxygen uptake (VO 2), carbon dioxide production (VCO 2), (VO 2 /VCO 2) ratio, pulmonary ventilation and HR were not significantly different between the groups. The indices for HR variability in the TD and FD for the two groups in the supine and seated positions were also not different. Conclusions: The use of oral contraceptives did not influence the aerobic capacity or the autonomic modulation of the HR. However, it influenced the total cholesterol and triglyceride levels. These assessments are important for determining protocols for physical training for cardiovascular disease prevention.