The impact of EEG biofeedback training on the athletes' motivation and bench press performance.

The objective of this paper was to determine the impact of EEG-biofeedback training on the motivation and efficiency of powerlifters during the bench press exercise in relation to the external load and the level of training. The study included 18 trained powerlifters who were divided into the intermediate (IG) and the advanced (AG) groups. EEG-biofeedback training was conducted every three days, lasting 27 minutes each time (5 × 3-minute intervals with recovery periods - lying on a bench - between them 4 × 3 minutes), and ended with a final EEG measurement in the second cycle of research. The repeated measures ANOVA showed intra-group differences due to external loading for the FAI (Frontal Alpha Asymmetry) obtained in the EEG both before and after biofeedback training. In AG group analysis revealed significant differences between 65%1RM and 35%1RM. In the IG group between 35%1RM and 50, 65 and 80%1RM. One of the major variables influencing the efficiency of strength training, including bench press workouts, is the level of training. The more successfully an athlete uses motivation when exercising, the better their training, which translates into greater results and a lower chance of injury.

Aerobic power across positions - an investigation into women's soccer performance.

OBJECTIVE: The aim of the study was to discern the disparities in the aerobic capacity of female athletes occupying various positions within a soccer team, and to understand the physical characteristics of the athletes in different positions. It is critical to understand that the physical demands for players vary depending on their positions on the field, a factor that greatly influences their training and gameplay. MATERIAL AND METHODS: The study engaged a sample of 25 female soccer players, average age of 22.72 (±2.69 SD), all of whom were active participants in the Chinese Women's Super League. The sample was distributed across several playing positions, including forwards, midfielders, and defenders. To gather pertinent data on oxygen uptake, a progressive load test was administered on a treadmill, coupled with a gas analyzer to amass respiratory indices (JAEGER, Germany). RESULTS: The study revealed that there was a notable variance in the maximum oxygen uptake among players in different positions. The midfielders exhibited the highest VO2 max at 63.24±7.04 ml/kg/min, followed by the forwards who averaged at 58.92±7.70 ml/kg/min, and finally the defenders who recorded the smallest average at 55.73±4.40 ml/kg/min. CONCLUSIONS: The outcomes of this study indicate that the positional role of a player in a team correlates with their aerobic capacity. Therefore, the positional demands significantly shape the player's physical characteristics, influencing their training and gameplay. This understanding is vital for the optimal conditioning of athletes in different positions in the sport of soccer.

C16orf72/HAPSTR1 is a molecular rheostat in an integrated network of stress response pathways.

All cells contain specialized signaling pathways that enable adaptation to specific molecular stressors. Yet, whether these pathways are centrally regulated in complex physiological stress states remains unclear. Using genome-scale fitness screening data, we quantified the stress phenotype of 739 cancer cell lines, each representing a unique combination of intrinsic tumor stresses. Integrating dependency and stress perturbation transcriptomic data, we illuminated a network of genes with vital functions spanning diverse stress contexts. Analyses for central regulators of this network nominated C16orf72/HAPSTR1, an evolutionarily ancient gene critical for the fitness of cells reliant on multiple stress response pathways. We found that HAPSTR1 plays a pleiotropic role in cellular stress signaling, functioning to titrate various specialized cell-autonomous and paracrine stress response programs. This function, while dispensable to unstressed cells and nematodes, is essential for resilience in the presence of stressors ranging from DNA damage to starvation and proteotoxicity. Mechanistically, diverse stresses induce HAPSTR1, which encodes a protein expressed as two equally abundant isoforms. Perfectly conserved residues in a domain shared between HAPSTR1 isoforms mediate oligomerization and binding to the ubiquitin ligase HUWE1. We show that HUWE1 is a required cofactor for HAPSTR1 to control stress signaling and that, in turn, HUWE1 feeds back to ubiquitinate and destabilize HAPSTR1. Altogether, we propose that HAPSTR1 is a central rheostat in a network of pathways responsible for cellular adaptability, the modulation of which may have broad utility in human disease.

Class-specific interactions between Sis1 J-domain protein and Hsp70 chaperone potentiate disaggregation of misfolded proteins.

Protein homeostasis is constantly being challenged with protein misfolding that leads to aggregation. Hsp70 is one of the versatile chaperones that interact with misfolded proteins and actively support their folding. Multifunctional Hsp70s are harnessed to specific roles by J-domain proteins (JDPs, also known as Hsp40s). Interaction with the J-domain of these cochaperones stimulates ATP hydrolysis in Hsp70, which stabilizes substrate binding. In eukaryotes, two classes of JDPs, Class A and Class B, engage Hsp70 in the reactivation of aggregated proteins. In most species, excluding metazoans, protein recovery also relies on an Hsp100 disaggregase. Although intensely studied, many mechanistic details of how the two JDP classes regulate protein disaggregation are still unknown. Here, we explore functional differences between the yeast Class A (Ydj1) and Class B (Sis1) JDPs at the individual stages of protein disaggregation. With real-time biochemical tools, we show that Ydj1 alone is superior to Sis1 in aggregate binding, yet it is Sis1 that recruits more Ssa1 molecules to the substrate. This advantage of Sis1 depends on its ability to bind to the EEVD motif of Hsp70, a quality specific to most of Class B JDPs. This second interaction also conditions the Hsp70-induced aggregate modification that boosts its subsequent dissolution by the Hsp104 disaggregase. Our results suggest that the Sis1-mediated chaperone assembly at the aggregate surface potentiates the entropic pulling, driven polypeptide disentanglement, while Ydj1 binding favors the refolding of the solubilized proteins. Such subspecialization of the JDPs across protein reactivation improves the robustness and efficiency of the disaggregation machinery.

Insulin/IGF-1 signaling and heat stress differentially regulate HSF1 activities in germline development.

Germline development is sensitive to nutrient availability and environmental perturbation. Heat shock transcription factor 1 (HSF1), a key transcription factor driving the cellular heat shock response (HSR), is also involved in gametogenesis. The precise function of HSF1 (HSF-1 in C. elegans) and its regulation in germline development are poorly understood. Using the auxin-inducible degron system in C. elegans, we uncovered a role of HSF-1 in progenitor cell proliferation and early meiosis and identified a compact but important transcriptional program of HSF-1 in germline development. Interestingly, heat stress only induces the canonical HSR in a subset of germ cells but impairs HSF-1 binding at its developmental targets. Conversely, insulin/insulin growth factor 1 (IGF-1) signaling dictates the requirement for HSF-1 in germline development and functions through repressing FOXO/DAF-16 in the soma to activate HSF-1 in germ cells. We propose that this non-cell-autonomous mechanism couples nutrient-sensing insulin/IGF-1 signaling to HSF-1 activation to support homeostasis in rapid germline growth.

Selective Hsp70-Dependent Docking of Hsp104 to Protein Aggregates Protects the Cell from the Toxicity of the Disaggregase.

Hsp104 is a yeast chaperone that rescues misfolded proteins from aggregates associated with proteotoxic stress and aging. Hsp104 consists of N-terminal domain, regulatory M-domain and two ATPase domains, assembled into a spiral-shaped hexamer. Protein disaggregation involves polypeptide extraction from an aggregate and its translocation through the central channel. This process relies on Hsp104 cooperation with the Hsp70 chaperone, which also plays important role in regulation of the disaggregase. Although Hsp104 protein-unfolding activity enables cells to survive stress, when uncontrolled, it becomes toxic to the cell. In this work, we investigated the significance of the interaction between Hsp70 and the M-domain of Hsp104 for functioning of the disaggregation system. We identified phenylalanine at position 508 in Hsp104 to be the key site of interaction with Hsp70. Disruption of this site makes Hsp104 unable to bind protein aggregates and to confer tolerance in yeast cells. The use of this Hsp104 variant demonstrates that Hsp70 allows successful initiation of disaggregation only as long as it is able to interact with the disaggregase. As reported previously, this interaction causes release of the M-domain-driven repression of Hsp104. Now we reveal that, apart from this allosteric effect, the interaction between the chaperone partners itself contributes to effective initiation of disaggregation and plays important role in cell protection against Hsp104-induced toxicity. Interaction with Hsp70 shifts Hsp104 substrate specificity from non-aggregated, disordered substrates toward protein aggregates. Accordingly, Hsp70-mediated sequestering of the Hsp104 unfoldase in aggregates makes it less toxic and more productive.

Adenosine diphosphate restricts the protein remodeling activity of the Hsp104 chaperone to Hsp70 assisted disaggregation.

Hsp104 disaggregase provides thermotolerance in yeast by recovering proteins from aggregates in cooperation with the Hsp70 chaperone. Protein disaggregation involves polypeptide extraction from aggregates and its translocation through the central channel of the Hsp104 hexamer. This process relies on adenosine triphosphate (ATP) hydrolysis. Considering that Hsp104 is characterized by low affinity towards ATP and is strongly inhibited by adenosine diphosphate (ADP), we asked how Hsp104 functions at the physiological levels of adenine nucleotides. We demonstrate that physiological levels of ADP highly limit Hsp104 activity. This inhibition, however, is moderated by the Hsp70 chaperone, which allows efficient disaggregation by supporting Hsp104 binding to aggregates but not to non-aggregated, disordered protein substrates. Our results point to an additional level of Hsp104 regulation by Hsp70, which restricts the potentially toxic protein unfolding activity of Hsp104 to the disaggregation process, providing the yeast protein-recovery system with substrate specificity and efficiency in ATP consumption.

Post-Effort Changes in Activity of Traditional Diagnostic Enzymatic Markers in Football Players' Blood.

BACKGROUND: Long-term and intensive physical effort causes metabolic and biochemical adaptations for both athletic and non-athletic objectives. Knowing the importance of aerobic training in football players, the aim of this study was to evaluate changes in the activity of: creatinine kinase (CK), creatine kinase MB (CKMB), lactate dehydrogenase (LDH), α-hydroxybutyrate dehydrogenase (HBDH), cholinesterase (ChE) and alkaline phosphatase (ALP) in response to a semi-long distance outdoor run under aerobic conditions among both female and male football players. METHODS: Sixteen participants aged 21.9±2 years (women) and 18.4±0.5 years (men), all of them voluntarily recruited football players, took part in an outdoor run, the women covering a distance of 7.4±0.3 km while men covered a distance of 10.7±1.0 km. Plasma activities of the studied enzymes were determined using an appropriate diagnostic assay kit. RESULTS: Our results indicate that total LDH activity could be a useful tool in evaluating physical fitness among athletes. We simultaneously established that ChE could not be a marker useful in assessing metabolic response to physical effort in athletes. Moreover, our results suggest that post-effort changes in ALP activity might be used to estimate early symptoms of certain vitamin deficiencies in an athlete's diet. CONCLUSIONS: We confirmed that the assessment of activity of selected traditional diagnostic enzymatic markers provides information about muscle state after physical effort.

Post-effort chances in C-reactive protein level among soccer players at the end of the training season.

Numerous literature data point out the differences in immunological parameters as a result of physical effort and the relation of those changes to the subject's fitness level. This study was aimed at the assessment of soccer players' condition and adaptation to physical effort based on the changes in C-reactive protein (CRP) blood level. C-reactive protein, total protein, and albumin plasma levels before and after 60-minute-long outdoor running were determined among 16 (8 men and 8 women) soccer players. Statistically significant increase in total blood protein level was observed in both studied groups. However, there were no statistically significant changes in albumin level in soccer players' blood. Determination of CRP showed that the exercise test caused changes in its level among both women and men; yet, statistically significant increase in CRP level was found only in women's blood. The different influence of effort on CRP plasma level may be explained by the involvement of various mechanisms in regulation of acute-phase responses in different conditions. It was found in our study that CRP level could be a valuable tool to assess the metabolic response to aerobic exercise.

Could biochemical liver profile help to assess metabolic response to aerobic effort in athletes?

Monitoring and optimizing the effectiveness of training course require wide analyses of athletes' blood parameter changes. The aim of this study was to evaluate the usefulness of biochemical liver profile to assess the metabolic response to semi-long-distance outdoor run in football players. Sixteen football players run outdoor for 60 minutes to achieve aerobic metabolism. Plasma activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), γ-glutamyltransferase (GGT) and plasma levels of total and direct bilirubin were determined in samples obtained before exercise test (pre-exercise) and immediately after the run (post-exercise). Mean AST plasma activity (U·L-1) before/after the exercise, respectively, was 78.3/228.3 in women and 76.5/56.2 in men. Mean ALT plasma activity (U·L-1) before/after the exercise, respectively, was 27.5/59.1 in women and 36.2/35.3 in men. Mean GGT plasma activity (U·L-1) before/after the exercise, respectively, was 39.3/76.6 in women and 44.7/71.2 in men. Plasma levels of total and direct bilirubin were similar before and after the run regardless of the gender. Statistical significance of the differences between results obtained pre- and post-exercise occurred in women (p = 0.0212 for AST; p = 0.0320 for ALT; p = 0.0067 for GGT, respectively). The training monitoring in athletes should be performed using measurements of performance and biological or physiological parameters. It was found that AST, ALT, and GGT activities could be a valuable tool to assess the metabolic response in high-level fitness female athletes. Therefore, monitoring of those well-known diagnostic markers could prevent the trainee from harmful overtraining.