Search Results (2,875)

Background: Evidence on the relationship between coffee, caffeine and depression remains inconsistent. Observational studies often report inverse associations, whereas experimental findings indicate potential adverse effects on anxiety and sleep. As a psychostimulant, caffeine increases alertness and perceived energy and may transiently improve mood and task engagement. Objective: This narrative review aims to reinterpret existing evidence on coffee and caffeine in depression from a symptom-level perspective, with emphasis on sleep–wake regulation, anxiety sensitivity, habitual use and withdrawal-related phenomena. Methods: Human studies published between 2000 and 2025 were synthesised narratively based on their relevance to depressive symptoms, arousal regulation, sleep and behavioural patterns of caffeine use, rather than for pooled effect estimation. Results: Caffeine may transiently alleviate fatigue and psychomotor slowing, but these effects are context-dependent and frequently counterbalanced by sleep disruption, anxiety and withdrawal-related fluctuations. Inverse associations observed in cohort studies may partly reflect reverse causality, residual confounding and relief of withdrawal symptoms rather than true antidepressant effects. Conclusions: Coffee and caffeine should not be conceptualised as antidepressant interventions. Instead, they appear to act as context-dependent modulators of symptom expression in depression, particularly affecting fatigue, alertness and sleep–wake stability. Failure to account for dose, habitual use, withdrawal and individual vulnerability may lead to overinterpretation of epidemiological findings in nutripsychiatric research. Full article

Background: The optimal frequency of EEG biofeedback sessions for elite athletes remains unclear, despite growing adoption of neurofeedback in high-performance sport. Methods: This randomized, controlled study compared three EEG biofeedback protocols (daily, every-other-day, every-third-day) in 24 national-level male judo athletes stratified into three phenotypic groups. Each protocol comprised 15 standardized sessions. Pre- and post-intervention assessments included functional indices (strength, power) and neurophysiological measures (Frontal Alpha Index, EMG amplitude/RMS, corrected strength sum). Biosensor performance was validated via signal quality metrics. Results: Daily EEG biofeedback produced superior improvements in strength, FAI, and fatigue resistance. Although LRG showed the largest pre–post RMS increase (+17.44 μV vs. +16.54 μV in HRG), HRG maintained the highest post-intervention RMS values and best fatigue resistance (MF_drop = −2.15 Hz). Significant group × time interactions were observed for FAI (p = 0.027) and RMS (p = 0.019). Every-other-day protocols yielded moderate gains, while every-third-day protocols produced minimal or maladaptive EMG–load dynamics. A robust dose–response relationship was evident. Conclusions: Session frequency is critical for optimizing neurofeedback interventions in elite athletes. Daily EEG biofeedback confers superior adaptation compared to less frequent dosing. Full article

Background: Fasting-based interventions are increasingly investigated as adjuncts to cancer treatment for the potential to reduce therapy-related toxicities, improve metabolic health, and enhance quality of life. However, clinical evidence regarding their efficacy, tolerability, and acceptability remains limited and fragmented. This scoping review aimed to systematically map the current evidence on fasting-based interventions in cancer patients and survivors. Methods: A literature search was conducted in PubMed, Scopus, Web of Science, and CINAHL up to 10 June 2025. Eligible interventional studies included cancer patients or survivors and evaluated fasting-based interventions, such as time-restricted eating, intermittent fasting, short-term fasting, or fasting-mimicking diets. Studies were categorized by fasting types and outcomes like fatigue, treatment toxicity, metabolic and hematologic parameters, weight, quality of life, adherence, acceptability, illness perception, and adverse events were assessed. Result: Twenty interventional studies of FMD, TRE, STF, IF, or fasting combined with altered dietary approaches conducted across 10 countries were included, comprising a total of 871 participants. Participant ages ranged from 28 to 75 years. Overall, 9 of 20 studies exclusively enrolled breast cancer patients or survivors, and chemotherapy was the most common treatment context in 11 studies. Five of six studies reported reductions in fatigue. Among the five studies assessing quality of life, one demonstrated improvement, three reported no change, and one yielded mixed results. Six of eight studies reported reductions in chemotherapy-related toxicity, and weight loss was observed in 10 of 12 studies. Reductions in IGF-1 and insulin levels were reported in six of seven and four of five studies, respectively. Hematologic changes were noted in six studies, and only one study assessed illness perceptions, reporting positive findings. Fasting-related adverse events, reported in nine studies, were generally mild and transient. High adherence and acceptability were observed across studies; however, findings were heterogeneous across intervention types and were largely derived from small or moderate-strength studies. A descriptive quality metric assessment indicated that most studies were of moderate methodological strength. More intensive fasting protocols, such as FMD and STF, appeared to demonstrate more consistent metabolic effects, whereas TRE showed higher adherence but more variable clinical outcomes. Conclusions: Fasting-based interventions have the potential to be feasible and well tolerated among cancer patients and survivors, with early evidence suggesting benefits in reducing fatigue, minimizing treatment-related toxicities, and favorable metabolic effects. Large, well-designed trials including diverse cancer populations are needed to confirm long-term outcomes and guide clinical integration. Full article

The present study investigates the thermo-mechanical behaviour and fatigue life associated with the shrink-fit process of shrink-fit tool holders. These holders are an indispensable component of high-precision and high-speed machining processes in modern manufacturing industries. Shrink-fit holders are subjected to elevated levels of stress as a consequence of repeated heating and cooling cycles, which can result in clamping fatigue over time. In this study, a three-dimensional finite element model (FEM) of a holder manufactured from H13 tool steel in accordance with BT40 standards was created using ANSYS software. The numerical analyses included transient thermal and structural analyses, consisting of a 4.5-s induction heating stage at 10 kW power, followed by a 1200-s cooling process. The analysis yielded results that were corroborated by the experimental data. It was established that, upon the conclusion of the heating process, the temperature in the conical region of the holder attained a range of approximately 388–417 °C. Furthermore, it was ascertained that a radial expansion of approximately 17.2–22 µm, which is required for the successful insertion of the cutting tool into the inner bore, was achieved. The fatigue life prediction, which constitutes the main focus of the study, applied the Soderberg criterion and evaluated two basic loading scenarios: the first tool assembly and repeated tool assembly cycles. The calculations yielded a life estimate of approximately 12,407 cycles for the first tool assembly cycle and approximately 19,400 cycles for the repeated tool assembly cycle. Accordingly, the repeated tool assembly condition exhibited a longer fatigue life than the first tool assembly condition. The enhanced longevity observed in the repeated tool assembly scenario is attributed to the stress cycle not fully reaching zero during this process, resulting in a lower stress amplitude. Full article

Background/Objectives: Over the last two decades, there has been a substantial change in the understanding of post-traumatic hypopituitarism (PTHP), which is no longer regarded as a marginal phenomenon. Clinical manifestations of pituitary hormone deficiency are frequently nonspecific, with fatigue and cognitive dysfunction predominating. Given that head injuries currently constitute a global burden for healthcare systems, the aim of the present study was to determine whether self-reported post-mild traumatic brain injury (mTBI) symptoms that may indicate hypopituitarism reflect true pituitary insufficiency or are attributable to other hormonal aberrations. The study aimed to assess the relationship between self-reported symptoms of PTHP and hormonal test results following mTBI. Setting: Patients were recruited from a tertiary trauma center Emergency Department (ED) in northern Poland from January 2023 to October 2025. Participants: The participants were adult (18 > y.o.) individuals with mTBI who met the inclusion criteria. Design: This was a prospective cohort study. During their post-head injury admission to the ED, patients had a blood sample taken. The procedure was repeated consecutively after 3, 6 and 12 months. After 6 and 12 months, patients were asked to complete a questionnaire. Methods: Pituitary and thyroid hormones were measured using the chemiluminescence immunoassay method and the heterogenous immunochemiluminescence method. The questionnaire used, Questionnaire for the Assessment of Symptoms of Anterior Pituitary Insufficiency in Patients After Mild Traumatic Brain Injury (mTBI) Hospitalized in the Emergency Department, was designed for the purposes of this study. Results: Self-reported symptoms suggestive of anterior pituitary dysfunction following mTBI were not confirmed by laboratory assessment of pituitary hormones. However, after 6 months, a statistically significant correlation was found between the number of reported symptoms and prolactin levels (ρ = 0.730; p = 0.0013), whereas after 12 months a downward trend in free triiodothyronine (fT3) levels was observed compared with the baseline. Conclusions: Persistent symptoms reported by patients following mTBI at 6 and 12 months, particularly fatigue and impaired concentration, showed statistical associations with prolactin levels at 6 months and lower fT3 levels at 12 months. These findings reflect correlations identified in the statistical analysis and do not support inferences regarding causality or the presence of true PTHP. Full article

Accurate perception and interpretation of the road environment are essential for safe driving. Vertical traffic signs play a key role in communicating warnings, regulations, and guidance to road users, thereby supporting safe and efficient traffic flow. However, their effectiveness depends not only on proper design and placement but also on how accurately and promptly they are perceived by drivers, which may be influenced by factors such as attention, cognitive workload, physical and mental condition, and fatigue. This study evaluates the contribution of selected vertical traffic signs to driving safety along a designated roadway section in Şanlıurfa, Türkiye. Face-to-face surveys were conducted with 480 active road users. Drivers’ knowledge, compliance behavior, safe route preferences, perceived visibility, and the effects of missing or inadequate signage were analyzed. The results indicate that driving exposure, education level, and experience significantly influence knowledge and perception of traffic signs, while compliance shows limited variation. These findings suggest that knowledge alone does not necessarily translate into behavioral compliance and underscore the importance of considering both driver-related factors and infrastructure characteristics in traffic safety strategies. The study provides practical insights for improving the visibility, placement, and overall effectiveness of vertical traffic signs in rapidly developing urban environments. Full article

Rheumatoid arthritis (RA) is a chronic autoimmune rheumatic disease of unknown etiolgy, characterized by erosive polyarthritis that leads to joint destruction and systemic inflammatory lesions in internal organs. Pain is a primary symptom of RA and a major contributor to psychological disturbances, which influence patients’ subjective evaluation of their condition. These psychological issues may stem from disruptions in central pain regulation mechanisms, such as central sensitization (CS), which can also affect central metabolic processes. The objective was to investigate how the severity of central sensitization, measured by the Central Sensitization Inventory (CSI) questionnaire (Part 1), impacts clinical and neuropsychiatric parameters, as well as the expression of genes related to inflammation, tissue destruction, carbohydrate metabolism, and fatty acid metabolism in peripheral blood mononuclear cells (PBMCs) in patients with RA. Methods involved collecting blood samples from 59 RA patients (mean age 52.0 years). Clinical status was assessed using the DAS28 index and serum levels of CRP, ASPA, and RF. Neuropsychiatric parameters were evaluated through questionnaires measuring CS severity score (CSI), pain intensity (VAS, BPI), neuropathic pain (PainDETECT), anxiety and depression (HADS), fatigue (FSS, FACIT-F), fibromyalgia symptoms (FIRST), and pain catastrophizing. Protein expression in PBMCs was measured by ELISA, while gene expression was analyzed using quantitative real-time RT-PCR. All patients exhibited moderate to high disease activity. Participants were divided into four subgroups according to their CSI scores: subclinical (0–29 points), mild (30–39 points), moderate (40–49 points), and severe/extreme (50–100 points). Higher CSI scores correlated with significant increases in neuropsychiatric symptoms and a notable decrease in vitality. However, clinical parameters showed no significant differences among the subgroups. Gene expression analysis revealed upregulation of genes involved in the pentose phosphate pathway (G6PD), antioxidant defense (SOD1), fatty acid metabolism (FASN, CPT1B), apoptosis (CASP3), and tissue destruction and hypernociception (MMP-9) compared to healthy controls. The pro-inflammatory cytokine IL-1β expression was comparable to controls, while TNFα expression was elevated only in patients with severe/extreme CS scores. These findings suggest that CS-related disturbances may contribute to increased disease severity in RA, even in patients receiving active antirheumatic treatment. At the cellular level, disease severity appears linked to dysregulated expression of genes governing central metabolic processes, despite low expression of pro-inflammatory cytokine genes. Full article

This paper presents the first study on the fatigue damage behavior of seawater sea-sand concrete (SSC) and its modeling. Experimental tests were conducted on cylindrical specimens subjected to uniaxial compression, investigating the effects of maximum stress level and material variability. The results indicate that the maximum stress-fatigue life curve for SSC can be well represented by a straight line, while the secant stiffness of SSC degrades in a two-phase process: initially in a decelerating manner, followed by an accelerating degradation until failure. Compared to ordinary concrete, SSC exhibits a significantly longer fatigue life. Due to material variability, the fatigue life of SSC shows considerable randomness, which can be effectively modeled using a Weibull distribution. A modification was made to a recently proposed damage model by the author and Li to capture the stochastic fatigue damage evolution behavior of SSC. The modified model successfully simulates both the maximum stress-fatigue life curve and the secant stiffness degradation curve, including their inherent randomness. Future research should explore the underlying specific factors contributing to the significantly longer fatigue life of SSC compared to ordinary concrete. Full article

Background/Objectives: Reaction time, hand–eye coordination, spatial orientation, and attention play a key role in handball, which is characterized by high intensity as well as high cognitive and motor demands. The level of these abilities may change during the season, potentially reflecting training adaptations and increasing physical fatigue. The aim of the study was to compare the level of psychomotor abilities in professional handball players before the start of the competition round and after the end of the league season. The study included 77 handball players playing in the Polish Handball Super League (average age: 25.6 ± 5.2 years). The players were divided according to position: pivot, center, and wing. Methods: Psychomotor abilities were assessed using the Test2Drive computer system, employing tests of simple and choice reaction time, eye–hand coordination, spatial orientation, perception and attention, and movement anticipation. Results: At the end of the season, a statistically significant reduction in reaction time was observed in the choice reaction (p = 0.001), eye–hand coordination (p = 0.002), and spatial orientation tests (p = 0.003). In terms of motor skills, an increase in time was observed in the SIRT test (p = 0.003), CHORT (p = 0.005) and HECOR (p = 0.011) tests, while the time in the PUT test was shortened for both neutral (p = 0.002) and critical (p = 0.025) stimuli. Positional analysis showed that after the season, the pivot player achieved higher effectiveness in the CHORT test than the wing player (p = 0.020). Additionally, statistically significant differences were observed for correct responses in the SPANT test (p = 0.032). In terms of correct answers in the PAMT test, the pivot player had the lowest effectiveness. Conclusions: Participation in the full season of competition coincided with significant changes in the psychomotor profile of handball players, with a simultaneous improvement in reaction speed and deterioration in movement time parameters. Full article

Background/Objectives: Youths with cerebral palsy (CP) have reduced levels of physical activity (PA) due to motor impairments and functional difficulties. Few studies have observed its link with various factors and none in young adults with CP. This study aimed to investigate the relationships between PA and various factors in young adults with CP, such as gait function, endurance, participation, and personal/environmental influences. Methods: Participants over 15 years old with CP who underwent Clinical Gait Analysis (CGA), the 6 min walk test, and wore an actimeter (ActiGraph GT3X+) for seven days were included. PA was assessed by daily step count (NbSteps/day). Explanatory factors included the Gait Profile Score (GPS), walking speed, subjective walking perception, joint pain, fatigue, 6 min walk distance, SF-36 questionnaire scores, and lifestyle habits. Correlations, univariate, and multivariate regression models were used for the analysis. Results: Forty-seven CP patients (28 males, 19 females, mean age 23.6 years) were included, with 82% classified as GMFCS I and 18% as GMFCS II. The average NbSteps/day was 5685. Significant correlations were found between NbSteps/day and subjective perception, pain, GMFCS level, and walking speed. Multivariate regression identified walking speed and physiotherapy (PT) sessions as significant predictors of PA. Conclusions: PA in young adults with CP is linked to walking speed, GMFCS level, joint pain, fatigue, and PT. No differences have been observed between patient unilateral or bilateral CP. However, individual behaviors vary and are not fully explained by linear regression analysis. Full article

This article addresses physical activity during pregnancy and the postpartum period, a crucial public health concern. We examine the latest insights into physical activity during the perinatal phase, highlighting key findings on the attitudes, perceived barriers, and factors that influence participation. Engaging in moderate physical activity during this period is deemed safe and offers numerous benefits, such as lowered risks of gestational diabetes, preeclampsia, and excessive weight gain, alongside enhanced mental health and sleep quality. After childbirth, continued physical activity provides advantages such as weight management, reduced postpartum depression risk, improved sleep patterns, and a better overall quality of life. However, activity during these stages is often hindered by various barriers stemming from personal issues, societal influences, knowledge gaps, and environmental obstacles. Notably, these challenges tend to shift between pregnancy and postpartum; safety concerns are more prevalent during pregnancy, while issues like fatigue, lack of time, and childcare responsibilities become more significant after delivery. This article uses a socio-ecological framework to analyze these obstacles in depth, categorizing them into intrapersonal, interpersonal, environmental, organizational, and policy-based levels. Full article

Esports are a rapidly expanding form of competitive activity that demand high levels of cognitive alertness, motor precision, stress management, and resilience to mental and physical fatigue. At the same time, the sedentary lifestyle, extended screen exposure, and psychological pressures associated with competitive gaming raise concerns for both performance and long-term health. Growing evidence highlights the importance of nutrition and lifestyle behaviors in supporting cognitive performance and overall competitive demands. While balanced dietary patterns and adequate hydration are essential, dietary supplements may provide additional benefits when used appropriately and under professional guidance. However, the current research is limited by a predominance of cross-sectional and self-reported studies, short-term or acute interventions, small sample sizes, and insufficient emphasis on esports-specific and personalized strategies. This review examines existing evidence on individualized nutrition, supplementation, and lifestyle strategies in esports, identifies key methodological limitations, and outlines future directions to inform evidence-based practice for athletes, practitioners, and organizations seeking to optimize cognitive performance, well-being, and long-term sustainability in this emerging field. Full article

Fatigue and reduced energy availability significantly affect athletic performance, and nutritional strategies to maintain carbohydrate and electrolyte levels are critical for delaying fatigue and preserving endurance. This study aimed to evaluate the effects of carbohydrate and electrolyte (CHO-E) supplementation on sports performance in physically active individuals. A systematic review and meta-analysis of 26 studies, including randomised and observational designs, was conducted. Four separate analyses examined the impact of CHO-E supplementation on performance outcomes, metabolic biomarkers, blood mineral concentrations, and additional performance descriptors. The meta-analysis showed that CHO-E supplementation significantly increased time to exhaustion (Standard Mean Difference (SMD) 0.60; 95% confidence interval (CI): 0.17, 1.02; p = 0.006), blood glucose levels (SMD 0.82; 95% CI: 0.45, 1.19; p < 0.001), and blood sodium levels (SMD 0.22; 95% CI: 0.07, 0.36; p = 0.004) compared to placebo, while no significant effect was observed for time to finish (SMD −0.07; 95% CI: −0.28, 0.13; p = 0.49). These findings indicate that CHO-E supplementation during moderate-to-high intensity exercise can enhance performance by extending endurance and supporting metabolic and electrolyte balance. Overall, the results support the targeted use of CHO-E supplementation to maintain energy availability and physiological stability during prolonged physical activity, providing evidence-based guidance for athletes and practitioners. Full article

Low back pain (LBP) represents an immense economic burden, with a lifetime prevalence of up to 84%. However, conventional diagnostic methods such as Magnetic Resonance Imaging (MRI) or X-rays provide only limited information about the pathogenesis and specific pain-related functional limitations. Wearable inertial sensors (IMU) and electromyography sensors (EMG) offer an expanded spectrum for the targeted identification and diagnosis of LBP. The aim of the study is to develop and evaluate a standardized multi-sensor functional assessment protocol for the subcategorization of functional deficits in LBP. Based on a systematic literature review, a standardized and objectively measurable functional LBP assessment protocol was defined that tests fatigue resistance, neuromuscular control, lumbopelvic stability, and global trunk musculature. Subsequently, 38 individuals were recruited in a prospective cross-sectional study and divided into three groups: “healthy,” “mild pain,” and “severe pain.” These individuals underwent an assessment. The two pain groups differed significantly from the symptom-free individuals in all previously defined functional levels. In addition, the two pain groups also differed significantly from each other. The functional assessment, which incorporates IMUs and EMG sensors as central diagnostic elements, enables the identification of functional deficits and associated neuromuscular characteristics, thus enabling individualized therapy. Full article

To elucidate the degradation behavior of elastic modulus in normal-strength ordinary concrete under flexural fatigue loading, this study systematically examines its evolution in C50 concrete, which is widely used in engineering applications. Based on four-point bending fatigue test data of plain concrete (PC) and reinforced concrete (RC) beams, degradation curves of the relative residual elastic modulus as a function of the cycle ratio were established. To quantitatively characterize the fatigue degradation process, two integrated indicators—the area under the curve (AUC) and the stable-stage degradation slope (|$K_{mid}$|)—were introduced to represent the degree of cumulative damage and the degradation rate of elastic modulus, respectively. These indicators were subsequently employed to evaluate the effects of maximum stress level, stress ratio, and reinforcement on elastic modulus degradation. The results show that failed PC specimens exhibited a typical three-stage S-shaped degradation pattern, whereas RC specimens primarily exhibited a two-stage degradation behavior. However, the elastic modulus of runout PC specimens remained above 93% of its initial value throughout the entire loading process. For PC specimens, under the same maximum stress level, increasing the minimum stress level from 0.10 to 0.25 resulted in a 24% decrease in |$K_{mid}$| from 0.2505 to 0.1912. At the same minimum stress level, increasing the maximum stress level from 0.75 to 0.90 led to a 94% increase in |$K_{mid}$| from 0.1912 to 0.3705. The presence of reinforcement increased AUC by 3~15% and reduced |$K_{mid}$| by 54~74%, indicating that reinforcement not only mitigated overall damage accumulation but also significantly slowed the degradation rate of the elastic modulus during the stable fatigue stage. The degradation characterization approach proposed in this study provides a simplified and practical framework for fatigue analysis of concrete components based on damage mechanics. Full article