To reduce transmission of the coronavirus, the Brazilian government adopted containment measures to control the virus’ spread, including limitations to the practice of physical activity. It was aimed to analyze the effects of COVID-19 quarantine on physical activity levels, energy expenditure, quality of life, and level of stress in a sample of the Brazilian population. The sample included 426 participants (7 to 80 years). The International Physical Activity Questionnaire, Short form survey-36 (SF-36), and Stress Perception Scale, were used to assess the level of physical activity, quality of life and stress, respectively. The anthropometric data was used to the assessment of body mass index and basal metabolic rate. Body weight increased significantly in all sample (p < 0.05). During the pandemic, 84% of the sample indicated a low level of physical activity. Furthermore, weekly energy expenditure decreased significantly in all age groups during the pandemic (children p < 0.0001; adolescents: p < 0.0001; adults p < 0.001, and elderly p < 0.0001). All aspects of quality of life, significantly reduced in both sexes in all age groups (p < 0.05). With the exception of children, stress levels increased significantly during the pandemic (adolescents: male: p = 0.003, female: p < 0.05; adults: male: p = 0.003, female: p = 0.01, and elderly: male: p = 0.02, female: p = 0.03). Findings from the present study suggests that COVID-19 social isolation has negatively affected Brazilian’ physical activity and quality of life.

Background and Objectives: The effects of warm-up in athletic success have gained strong attention in recent studies. There is, however, a wide gap in awareness of the warm-up process to be followed, especially in Paralympic powerlifting (PP) athletes. This study aimed to analyze different types of warm-up on the physical performance of PP athletes. Materials and Methods: The sample consisted of 12 elite Brazilian PP male athletes (age, 24.14 ± 6.21 years; bodyweight, 81.67 ± 17.36 kg). The athletes performed maximum isometric force (MIF), rate of force development (RFD), and speed test (Vmax) in three different methods of warm-up. Tympanic temperature was used to estimate the central body temperature. Results: A significant difference was observed for MIF in the without warm-up (WW) condition in relation to the traditional warm-up (TW) and stretching warm-up (SW) (p = 0.005, η2p = 0.454, high effect). On the contrary, no significant differences were observed in RFD, fatigue index (FI) and time in the different types of warm up (p > 0.05). Furthermore, no significant differences were observed in relation to the maximum repetition (p = 0.121, η2p = 0.275, medium effect) or the maximum speed (p = 0.712, η2p = 0.033, low effect) between the different types of warm up. In relation to temperature, significant differences were found for the TW in relation to the “before” and “after” conditions. In addition, differences were found between WW in the “after” condition and SW. In addition, WW demonstrated a significant difference in relation to TW in the “10 min later” condition (F = 26.87, p = 0.05, η2p = 0.710, high effect). Conclusions: The different types of warm-up methods did not seem to provide significant differences in the force indicators in elite PP athletes.

Background: Mechanisms that influence muscle strength can interfere with neuromotor performance and overall health, thus hormone markers and maturation can interact in this process. Objective: The present study aimed to verify the relationship of hormonal markers and biological maturation on neuromotor abilities in young people. Methods: This is a cross-sectional study with 44 female participants (11.5 ± 1.5 years). Hormones were analyzed biochemically. Skeletal and somatic maturation were analyzed using anthropometry. The muscular power of the upper and lower limbs, body speed with change of direction, and speed of the upper limbs were verified. Results: Bone age was correlated with hormonal markers (estradiol: r = 0.58; p = 0.0007), (testosterone: r = 0.51; p = 0.005). Peak growth velocity correlated with estradiol (r = 0.51; p = 0.004). The power of the lower limbs (estradiol: r = 0.52; p = 0.006; testosterone: r = 0.42; p = 0.03) and of the upper limbs (estradiol: r = 0.51; p = 0.007; testosterone: r = 0.42; p = 0.02) had a positive correlation with hormone levels and had similar results with maturation. The analysis by artificial neural networks indicated that the maturation can predict the neuromotor performance between 57.4% and 76%, while the hormonal markers showed a potential of more than 95% for the foreshadowing of the neuromotor performance of the upper limbs. Conclusion: It was possible to conclude that the hormones had a relationship with maturational development and bone age in female subjects.

Background: Endocrine mechanisms can be a determining factor in the neuromuscular performance of young athletes. Objective: The objective of the present study was to relate maturational and hormonal markers to neuromuscular performance, as well as to verify whether young athletes with different testosterone levels show differences in muscle strength. Methods: The sample consisted of 37 young male Brazilian athletes (11.3 ± 0.94 years) who were members of a sports initiation project. Hormonal markers were analyzed biochemically by blood samples, and maturation markers by mathematical models based on anthropometry. Body composition was verified by tetrapolar bioimpedance. The performance of upper and lower limb strength and body speed were analyzed. Results: Hormonal and maturational markers were related to neuromuscular performance (p < 0.05). Young people with higher testosterone levels showed higher muscle strength (p < 0.05). Artificial neural networks showed that testosterone predicted the performance of upper limbs by 49%, and maturation by 60%. Maturation foreshadowed the performance of lower limbs by 30.3%. Conclusion: Biological maturation and hormonal levels can be related to neuromuscular performance, and young people with higher testosterone levels show superior muscle strength in relation to the others.

This study aimed to identify the interactional relationships between maturation (biological age (BA)) and lean mass on strength development in young athletes from different sports. Using a cross-sectional study design, a sample of 64 young athletes (rowers, swimmers, jiu-jitsu, volleyball, soccer and tennis players) of both sexes (13.6 ± 1.17 years) were recruited. Body composition was assessed using dual energy bone densitometry with X-ray source (DEXA). Strength of upper limbs (ULS), force hand grip (HG), vertical jump (VJ) and jump against movement (CMJ) were recorded. BA was estimated from anthropometrics. BA relationships were identified with upper limb strength in all athletes, and with the lower limb strength of tennis players, only (p < 0.05). An interaction effect between lean mass and BA was found (η2p = 0.753), as was a local effect within the regression models (ƒ2 ≥ 0.33). Athletes with a higher concentration of lean mass had superior upper and lower limb strength (p < 0.05). Lean mass showed a local effect (ƒ2) greater than that associated with BA. Although maturation is related to strength development, the strength of the relationship is mitigated by the accrual of lean mass. Specifically, the local effect of lean mass on muscle strength is broader than that of maturation, especially for lower limb strength.

Background: Recovery from training is vital as it ensures training and performance to continue at high intensities and longer durations to stimulate the body and cause further adaptations. Objective: To evaluate different methods of post-workout recovery in Paralympic powerlifting athletes. Methods: Twelve male athletes participated (25.4 ± 3.3 years; 70.3 ± 12.1 kg). The presence of muscle edema, pain threshold, plasma cytokines, and performance measurement were evaluated five times. The recovery methods used in this study were passive recovery (PR), dry needling (DN), and cold-water immersion (CWI). Results: The data analysis showed that the maximal force decreased compared to the pretest value at 15 min and 2 h. The results also revealed that CWI and DN increased Interleukin 2 (IL-2) levels from 24 to 48 h more than that from 2 h to 24 h. After DN, muscle thickness did not increase significantly in any of the muscles, and after 2 h, muscle thickness decreased significantly again in the major pectoralis muscle. After CWI, pain pressure stabilized after 15 min and increased significantly again after 2 h for acromial pectoralis. Conclusion: The strength training sessions generate several changes in metabolism and different recovery methods contribute differently to maintain homeostasis in Paralympic powerlifting athletes.

Background: In Paralympic powerlifting (PP), athletes with and without spinal cord injury (SCI) compete in the same category. Athletes with SCI may be at a disadvantage in relation to the production of muscle strength and the execution of motor techniques. Objective: To analyze the indicators force, dynamic and static, at different intensities, on performance in athletes with and without SCI. Methods: The sample was composed of two groups of PP athletes: SCI (30.57 ± 4.20 years) and other deficiencies (OD; 25.67 ± 4.52 years). Athletes performed a test of maximum isometric force (MIF), time to MIF (Time), rate of force development (RFD), impulse, variability and fatigue index (FI), dynamic tests Mean Propulsive Velocity (MPV), Maximum Velocity (Vmax) and Power. Results: There were differences in the SCI in relation to OD, 50% 1RM (p < 0.05), in relation to MPV and Vmax. There were no differences in the static force indicators. Regarding EMG, there were differences between the SCI triceps in relation to the previous deltoid (p = 0.012). Conclusion: We concluded that the static and dynamic strength indicators are similar in Paralympic powerlifting athletes with spinal cord injury and other disabilities.

The aim of the present study was to analyze the effect of creatine (Cr) supplementation on peak torque (PT) and fatigue rate in Paralympic weightlifting athletes. Eight Paralympic powerlifting athletes participated in the study, with 25.40 ± 3.30 years and 70.30 ± 12.15 kg. The measurements of muscle strength, fatigue index (FI), peak torque (PT), force (kgf), force (N), rate of force development (RFD), and time to maximum isometric force (time) were determined by a Musclelab load cell. The study was performed in a single-blind manner, with subjects conducting the experiments first with placebo supplementation and then, following a 7-day washout period, beginning the same protocol with creatine supplementation for 7 days. This sequence was chosen because of the lengthy washout of creatine. Regarding the comparison between conditions, Cr supplementation did not show effects on the variables of muscle force, peak torque, RFD, and time to maximum isometric force (p > 0.05). However, when comparing the results of the moments with the use of Cr and placebo, a difference was observed for the FI after seven days (U3: 1.12; 95% CI: (0.03, 2.27); p = 0.02); therefore, the FI was higher for placebo. Creatine supplementation has a positive effect on the performance of Paralympic powerlifting athletes, reducing fatigue index, and keeping the force levels as well as PT.