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Context: Exercise immunology is aimed at understanding how exercise sessions can affect the immune system in athletic subjects of different age groups. The objective of the current study was to discuss in which stage of biological maturation (BM) young athletes may be more vulnerable in relation to the immune system, and whether there is a BM range in which it is safer to perform sports training with strenuous exercise loads. Evidence Acquisition: Evidence from scientific research from several scientific disciplines (eg, immunology, sport immunology, pediatrics, sports medicine, human development) was gathered to holistically examine the main particularities of exercise immunology as applied to pediatric sport. Study Design: Narrative review. Level of Evidence: Level 5. Results: In pediatric patients, lymphoid tissue expands during puberty and involutes after puberty until it returns to pre-expansion values. This suggests that there is a specific period in which the immune system may be stronger, which may provide opportunities for strenuous exercise in pediatric athletes. However, the chronological period when puberty occurs will be determined by BM, which is the rate at which the biological systems of the human body improves. This may affect the period of lymphoid tissue expansion and, consequently, the behavior of the immune system in pediatric subjects of the same age category. Conclusion: During puberty, there is a significant increase in the proinflammatory profile; to compensate for this, there is an expansion of lymphoid tissue that may favor the efficiency of the immune system. The period in which puberty is reached may vary according to the stages of BM. Therefore, in exercise immunology applied to pediatric sports, in addition to external and internal training loads, it is necessary to consider BM and puberty, which have been shown to be safer biomarkers than chronological age for determining immune system behavior in pediatric athletes. Strength-of-Recommendation Taxonomy (SORT): Evidence B level 3. [ABSTRACT FROM AUTHOR]

Background/Objectives: Animal models can help understand human physiological responses, including the response to exercise and physical activity. However, many of these models incorporate noxious stimuli for various scientific purposes. We propose a noxious stimuli-free treadmill running training program for Rattus norvegicus species to study adaptations to aerobic exercise. Methods: In this study, rats were randomly allocated to training (n = 20) and sedentary (n = 20) groups. The training group underwent a program consisting of 30–50 min of treadmill running at 60% intensity, three times per week for 8 weeks. Maximum speed tasks (Tmax) were conducted to determine, adjust, and evaluate changes in fitness conditions. The rats had one week of familiarization with the treadmill, and a rubber ball was used at the back wall of the lane as a painless stimulus to encourage running. All assessments were conducted by two independent researchers in a double-blind manner, with data analysis conducted by a third-blind investigator. Results: A significant effect of time (η2p = 0.430, p < 0.001, large effect) could be found, showing differences between Tmax1 and Tmax2, and between Tmax1 and Tmax3 in both groups. The training group significantly outperformed the sedentary group (η2p = 0.266, p < 0.001, large effect). There was a significant interaction between time and condition (η2p = 0.152, p < 0.001, large effect). Conclusions: The proposed moderate-intensity treadmill running program could effectively differentiate between trained and sedentary conditions within both the short period of 4 weeks and the extended period of 8 weeks. This protocol can be used as a model for running on a treadmill for Rattus norvegicus species without the use of noxious stimuli. [ABSTRACT FROM AUTHOR]

Caffeine and sodium bicarbonate are extensively researched ergogenic aids known for their potential to enhance exercise performance. The stimulant properties of caffeine on the central nervous system, coupled with the buffering capacity of sodium bicarbonate, have been associated with improved athletic performance. This has led to investigations of their combined effects on strength. The aim of the present study is to investigate the effect of isolated and combined caffeine and sodium bicarbonate consumption on strength using the isometric mid-thigh pull test (IMTP). Nineteen male college students (age 23.6 ± 1.6 years) participated in this crossover, double-blind, placebo-controlled study. They were exposed to the following conditions: control (no supplement), placebo (20 g maltodextrin), caffeine (6 mg/kg), sodium bicarbonate (0.3 g/kg), and a combination of caffeine and sodium bicarbonate. Supplements and placebo were diluted in water and consumed 60 min prior to the IMTP tests. Two 5 s IMTP trials were performed at 40–60% and 60–80% of One Repetition of Maximum (1RM) with a 60 s rest between. Consumption of caffeine or Caf + NaHCO3 did not significantly change peak IMTP strength values at any intensity (p = 0.110). The peak IMTP values did not show significant differences between conditions or from control condition values (1091 ± 100 N) to Caf (1224 ± 92 N), NaHCO3 (1222 ± 74 N), and Caf ± NaHCO3 (1152 ± 109 N). However, the test of the results of the ANOVA analysis of repeated measures of effect within the caffeine condition was significant for the increase in IMTP relative strength compared to control (p < 0.05). Thus, the IMTP force values increased significantly from control to Caf (p = 0.016) and from Pla to Caf (p = 0.008), but not for other comparisons (p > 0.05). In summary, caffeine supplementation alone, taken 60 min before exercise, positively affects submaximal strength performance. In contrast, sodium bicarbonate, whether taken alone or in combination with caffeine, does not enhance submaximal strength in the IMTP tests. [ABSTRACT FROM AUTHOR]

Purpose. Stroke is the second most common cause of mortality worldwide and the third most common cause of motor disability. From another perspective, brain-derived neurotrophic factor (BDNF) is a metabolite that plays several neuroprotective roles. While cardiometabolic diseases are the leading cause of stroke, BDNF represents a target factor in the prevention and/or recovery from stroke. Aim: In this narrative review, we have summarised the clinical evidence of BDNF participation in the recovery from a stroke and discuss the potential use of exercise as a rehabilitation tool. Methods. Multiple combinations of the terms 'brain infarction', 'cerebral infarction', 'hemorrhagic stroke', 'ischemic stroke', 'embolic stroke' or 'thrombotic stroke' AND 'BDNF' or 'pro-BDNF' were used in PubMed databases. Studies not available in the English language or addressing animal experiments were excluded. Results and prospects. Seventeen clinical studies published up to June 30th of 2023 were included in this review. Changes in the patients circulating BDNF levels represent their capability of recovery from the stroke outcomes. A subtle, but consistent, negative influence of the presence of the 66Met-allele in BDNF on motor and cognitive competencies is seen in patients recovering from a stroke throughout the studies - an effect that is not reportedly detectable in other neuropathological conditions. Exercise exerts a positive modulation on BDNF levels that accompanies improvements in stroke recovery and might exert a preventive role against the severity of stroke outcomes. [ABSTRACT FROM AUTHOR]

We have previously demonstrated the relation between the biological maturation (BM) and the power of both upper (ULP) and lower limbs (LLP) in young athletes. We have also observed that the BM has a higher influence on the ULP, and the LLP is more prone to changes in hormonal and morphological factors. However, we have not yet compared the power of upper limbs and lower limbs in relation to the BM stage to verify whether the BM exerts more relation on the muscle power of a segment of the body. To attend this question, in this transverse study we have analyzed the relative muscle power from 241 young athletes (male: 57%, female: 43%, 12.3 ± 1.7 years) in relation to the BM stages of—delayed, synchronized and advanced. The ULP was verified by the medicine ball test and the LLP was verified by jump test in strength platform. Measures were standardized in Watts. The ULP was superior than LLP when individuals were at the late (male: p < 0.0001, female: p < 0.0001), or synchronized (male: p < 0.000, female: p = 0.0003) stages of BM, whereas no differences were found when the individuals were at the advanced stage of BM (male: p = 0.3, female: p = 0.3). Athletes at the late or synchronized stages of BM display of a higher power of superior compared inferior limbs. It is concluded that biological maturation has a greater relationship with the power of the upper limbs when compared to the lower limbs. [ABSTRACT FROM AUTHOR]

Background: Literature reports indicate changes in the expression of genes encoding proinflammatory factors are observed as a result of physical exercise. The stress changes caused by high-intensity loads and adaptive changes induced by the planned long-term training are less studied. The aim of this study was to determine the impact of intense anaerobic effort in people adapted to regular trainings and in non-trained persons on the expression levels of the TNFA gene. Material and methods: 50 experienced soccer players and 50 non-trained participants were recruited for the study. Anaerobic capacity was measured by means of the Wingate Anaerobic Test. To evaluate the expression of TNFA gene, a QRT-PCR was applied. Results: A comparison of the TNFA expression profiles between well-trained athletes and non-trained controls revealed that transcript levels were higher in non-trained participants when compared with soccer players in all the studied time points, with the exception of the second post-test; however, this difference was the only one that was statistically insignificant. Conclusions: The TNFA mRNA expression characteristic described in our study indicated a significant downregulation of the TNFA expression observed in the course of time in experienced athletes reflecting molecular adaptation to physical effort caused by long-term training regime. [ABSTRACT FROM AUTHOR]