Search Results (162)

Given the high neuromechanical demands and frequent asymmetries in badminton, this study investigated the impact of a four-week asymmetry-targeted intervention on single-leg hop performance in elite junior badminton players and examined whether asymmetry-based indices could predict training responsiveness. Twenty-two national-level athletes (aged 15–18) were randomized into an experimental group (EG) undergoing neuromechanical training with EMG biofeedback or a control group (CG) following general plyometric exercises. Key performance metrics—Jump Height, Reactive Strength Index (RSI), Peak Power, and Active Stiffness—were evaluated pre- and post-intervention. Two novel composite indices, Force Efficiency Ratio (FER) and Asymmetry Impact Index (AII), were computed to assess force production efficiency and asymmetry burden. The EG showed significant improvements in Jump Height (p = 0.030), RSI (p = 0.012), and Peak Power (p = 0.028), while the CG showed no significant changes. Contrary to initial hypotheses, traditional asymmetry metrics showed no significant correlations with performance variables (r < 0.1). Machine learning models (Random Forest) using FER and AII failed to classify responders reliably (AUC = 0.50). The results suggest that targeted interventions can improve lower-limb explosiveness in youth athletes; however, both traditional and composite asymmetry indices may not reliably predict training outcomes in small elite groups. The results highlight the need for multidimensional and individualized approaches in athlete diagnostics and training optimization, especially in asymmetry-prone sports like badminton. Full article

Background: Emerging evidence indicates that some individuals recovering from COVID-19 develop persistent symptoms, including fatigue, pain, cognitive difficulties, and psychological distress, commonly known as Long COVID. These symptoms often overlap with those seen in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME), underscoring the need for integrative, non-pharmacological interventions. This Phase II controlled trial aimed to evaluate the feasibility and preliminary efficacy of Heart Rate Variability Biofeedback (HRV-BF) in individuals with Long COVID who meet the diagnostic criteria for CFS/ME. Specific objectives included assessing feasibility indicators (drop-out rates, side effects, participant satisfaction) and changes in fatigue, depression, anxiety, pain, and health-related quality of life. Methods: Participants were assigned alternately and consecutively to the HRV-BF intervention or Treatment-as-usual (TAU), in a predefined 1:1 sequence (quasirandom assignment). The intervention consisted of 10 HRV-BF sessions, held twice weekly over 5 weeks, with each session including a 10 min respiratory preparation and 40 min of active training. Results: The overall drop-out rate was low (5.56%), and participants reported a generally high level of satisfaction. Regarding side effects, the mean total Simulator Sickness Questionnaire score was 24.31 (SD = 35.42), decreasing to 12.82 (SD = 15.24) after excluding an outlier. A significantly greater improvement in severe fatigue was observed in the experimental group (H = 4.083, p = 0.043). When considering all outcomes collectively, a tendency toward improvement was detected in the experimental group (binomial test, p < 0.0001). Conclusions: HRV-BF appears feasible and well tolerated. Findings support the need for Phase III trials to confirm its potential in mitigating fatigue in Long COVID. Full article

Traditional relaxation techniques such as meditation and slow breathing often rely on subjective self-assessment, making it difficult to objectively monitor physiological changes. Electrocardiograms (ECG), which are commonly used by clinicians, provide one-dimensional signals to interpret cardiovascular activity. In this study, we introduce a visual interpretation framework that transforms heart rate variability (HRV) time series into fuzzy recurrence plots (FRPs). Unlike ECGs’ linear traces, FRPs are two-dimensional images that reveal distinctive textural patterns corresponding to autonomic changes. These visually rich patterns make it easier for even non-experts with minimal training to track changes in relaxation states. To enable automated detection, we propose a multi-domain feature fusion framework suitable for wearable systems. HRV data were collected from 60 participants during spontaneous and slow-paced breathing sessions. Features were extracted from five domains: time, frequency, non-linear, geometric, and image-based. Feature selection was performed using the Fisher discriminant ratio, correlation filtering, and greedy search. Among six evaluated classifiers, support vector machine (SVM) achieved the highest performance, with 96.6% accuracy and 100% specificity using only three selected features. Our approach offers both human-interpretable visual feedback through FRP and accurate automated detection, making it highly promising for objectively monitoring real-time stress and developing biofeedback systems in wearable devices. Full article

Persons with personality type D are characterized by an “unhealthy lifestyle”, which is manifested by low physical activity, less healthy eating behavior, and failure to comply with doctors’ recommendations. Persons with personality type D have an inadequate response of hemodynamic parameters to psychoemotional stress; the response of other parameters has not been sufficiently studied. The aim of this study was to investigate the association of personality type D with various psychophysiological parameters of the body during mental stress in healthy individuals. Material and Methods: The study involved 79 students of Kemerovo State Medical University aged 18 to 32 years (mean age 20.7 ± 2.4 years). Psychophysiological diagnostics was carried out using the BOSLAB complex; electromyogram, electrocardiogram, body temperature, respiration, galvanic skin response, and photoplethysmogram data were recorded. The stress testing protocol included cognitive tasks and recovery phases. Additionally, the presence of personality type D in students was assessed using the DS-14 questionnaire. The results of stress tests were compared in groups with the presence/absence of type D. Results: The frequency of detection of type D was high (54.4%). When examining the response of psychophysiological parameters, the most pronounced response to stress tests with mental load was noted for heart rate variability and respiratory system parameters. Individuals with type D personality showed more pronounced sympathetic activation in response to mental stress and a slower recovery at rest. Among the studied parameters, association with personality type D was noted for the following indicators during the mental arithmetic test: heart rate (p = 0.022), the Baevsky strain index (p = 0.004), respiratory rate (p = 0.020), and an indicator of regulatory process adequacy (p < 0.001). Conclusion: In the present study, we found differences in the reaction of psychophysiological parameters to mental stress in healthy individuals depending on the presence or absence of personality type D. These data can be useful for developing stress resistance programs and biofeedback training. The possibility of using the above psychophysiological parameters in biofeedback training programs for individuals with personality type D requires further research. Full article

Background/Objectives: Urinary incontinence (UI) is a frequent and distressing complication after radical prostatectomy (RP). Pelvic floor muscle training (PFMT) is widely recommended as first-line rehabilitation, yet the clinical factors influencing its effectiveness remain incompletely understood. Methods: This prospective cohort study included 182 men undergoing RP who completed a standardized physiotherapy program involving pelvic floor muscle exercises, biofeedback (BFB), and ultrasound-guided training. UI severity was assessed using the 1-h pad test and recorded absorbent product use. Outcomes were evaluated at three time points: one month, three months, and six months post-catheter removal. A multiple linear regression model was used to identify the predictors of continence improvement, defined as the change in pad test result between baseline and six months. Results: Pad test results and absorbent use decreased significantly across all UI severity stages (p < 0.0001). The greatest absolute improvement was observed in patients with severe incontinence at baseline (UI stage 3: mean reduction from 130.8 g to 23.7 g). Regression analysis revealed that only the baseline pad test result was significantly associated with the magnitude of improvement (β = 0.91; 95% CI: 0.85–0.97, p < 0.001; R² = 0.89). Age, BMI, and time to rehabilitation were not significant predictors. Conclusions: Pelvic floor rehabilitation after RP is effective in improving continence, including in patients with severe baseline symptoms. The baseline pad test value emerged as the strongest predictor of rehabilitation response, highlighting the importance of initial assessment. These findings support the use of PFMT in clinical practice and emphasize the need for individualized treatment planning based on baseline UI severity. Full article

The number of people suffering from urinary incontinence increases every year. Along this trend, the knowledge of society increases regarding the various methods available for treating this ailment. Both patients and researchers are constantly looking for new treatments for urinary incontinence. One of the new solutions is sonofeedback of the pelvic floor muscles, which may help to strengthen them and thus reduce the problem. The aim of this study was to evaluate the effectiveness of sonofeedback and transvaginal electrostimulation in increasing the bioelectrical activity of pelvic floor muscles in postmenopausal women with stress urinary incontinence. Sixty women with stress urinary incontinence were enrolled in the study. The patients were divided into two groups: A, where sonofeedback was used, and B, where electrostimulation of the pelvic floor muscles was performed with biofeedback training. In patients, the resting bioelectrical activity of the pelvic floor muscles was assessed using an electromyograph. The assessment of the resting bioelectrical activity of the pelvic floor muscles was performed before the therapy, after the 5th training, and after the therapy. It was observed that after the end of the therapy, the average bioelectrical potential increased by 1.1 µV compared with the baseline in group A. It can be suggested that the sonofeedback method is comparatively effective in reducing symptoms that are associated with urinary incontinence as an electrostimulation method with biofeedback training. Full article

The most common anorectal disorders are fecal incontinence, functional anorectal pain, and functional defecation disorders. They are often presented by overlapping symptoms with various degrees of severity. Therefore, a personalized approach to the patient is crucial for diagnosing and determining the prognosis of the disease. Biofeedback training is appropriate to consider when the motoric function disorder is known, the patient could learn voluntary control of response, and this could further lead to an improvement in the condition. Biofeedback is recommended for short-term and long-term treatment of constipation in adults and fecal incontinence in adults. It could also be considered for treatment of specific cases of anorectal pain. As office biofeedback is often time-consuming and comes with a substantially high cost, there is an emerging trend of home biofeedback administration. However, only a few significant studies have been published on this new approach. Although comprehensive data are needed to evaluate the proper strategy and development of various treatment protocols for different types of defecation disorders, home biofeedback therapy offers a potentially effective tool in the personalized treatment of defecation disorders. Full article

Background: Biofeedback (BFB) has long been a successful treatment for various mental health disorders. The purpose of this scoping review is to investigate the implementation of BFB in inpatient treatment concepts for the therapy of mental health disorders. Methods: Through a systematic search via Medline, PubMed, and the Web of Science, as well as a manual search in Google Scholar and reference lists, relevant articles published up to 30 December 2024 were identified. Studies were included if they focused on BFB interventions to treat mental health disorders in inpatient settings and were published in English or German. Studies were assessed by two independent raters, and key information was summarized in a shared document. Results: This scoping review analyzed 20 articles published between 1979 and 2022, examining BFB in inpatient settings for various mental health disorders, i.e., obsessive–compulsive disorder, depression, anxiety, substance use disorders, schizophrenia, and eating disorders. Positive outcomes were observed in symptoms, stress reduction, and improvements in cardiac autonomic and motor functions. The duration and frequency of the sessions varied widely, and different methodologies were used across studies, including controlled sessions and self-administered exercises. Conclusions: Most BFB inpatient studies showed positive effects on clinical symptoms. There was a broad heterogeneity of the studies. Comparisons are limited, making it challenging to give general recommendations for BFB implementation. The issue remains whether a methodologically consistent approach is necessary for clinical success. Full article

Sexual dysfunction following abdominal or pelvic surgery is a significant concern that impacts the quality of life (QoL) for both men and women. This paper explores the multifaceted challenges and re-educational strategies associated with post-surgical sexual dysfunction. It highlights the physical and psychological repercussions of surgeries such as hysterectomies, pelvic organ prolapse repairs, radical prostatectomies, and rectal cancer resections. These procedures often lead to complications like dyspareunia, erectile dysfunction, and altered body image, necessitating comprehensive re-educational approaches. The review emphasizes the importance of tailored interventions, including pelvic floor muscle training (PFMT), biofeedback, manual therapy, and advanced techniques like botulinum toxin injections and sacral neuromodulation. For men, strategies such as phosphodiesterase type 5 inhibitors (PDE5i), vacuum erection devices (VEDs), intracavernosal injections, and penile prostheses are explored for their efficacy in restoring erectile function. Psychological support, including cognitive–behavioral therapy and couples counseling, is underscored as essential to addressing emotional and relational aspects of recovery. A multidisciplinary approach involving physiatrists, urologists, gynecologists, physiotherapists, psychologists, and sexual health counselors is advocated for to optimize outcomes. Integrating physical therapy modalities, as well as psychological and relational therapies, into individual rehabilitation projects is crucial for improving sexual function and overall QoL post-surgery. Future research should focus on refining these established strategies and investigating the potential of innovative therapeutic modalities. Full article

(1) Background: Neurofeedback (NFB) and biofeedback (BFB) have been shown to reduce stress, enhance physiological self-regulation, improve cognitive performance, and accelerate response times. Stimulating the sensorimotor rhythm (12–15 Hz) is particularly effective in improving working memory and selective attention. However, most studies on air force pilots focus on addressing post-traumatic stress disorder rather than investigating how these interventions might enhance performance and safety during flights, as explored in the present study. (2) Methods: Twelve Spanish Air Force fighter pilot trainees (mean age = 22.83 (0.94) years) participated in the study. Six pilots underwent 24 sessions of combined NFB and BFB training (experimental group), while six served as controls. (3) Results: The experimental group demonstrated improved heart rate variability during baseline, alarm sounds, math tasks, and real flights, which is indicative of greater parasympathetic modulation. A significant decrease in the Theta/SMR ratio was observed in the experimental group during the same conditions, suggesting improved focus, with lower values than the control group. Cognitive performance improved in the experimental group, with higher accuracy and a greater number of completed operations during math tasks. Regarding dual-task performance, the experimental group showed lower reaction time and a better ratio taps/reaction post-intervention. Psychological benefits included reduced cognitive, somatic, and state anxiety levels, along with increased self-confidence. (4) Conclusions: Neurofeedback and biofeedback training, integrated with real flights, simulators, and virtual reality, can enhance physiological regulation, cognitive performance, and emotional resilience, contributing to improved performance and safety in air force pilots. Full article

This narrative review explores the significant evolution of sports rehabilitation, tracing its trajectory from basic exercise therapies of the early 20th century to the advanced, neuroplasticity-driven approaches of the 21st century, with a specific focus on anterior cruciate ligament reconstruction (ACLR). The primary aim is to understand how neuroplasticity, motor control, and sensorimotor retraining can optimize recovery, reduce reinjury risk, and enhance long-term athletic performance, and to synthesize current rehabilitation strategies that integrate innovative technologies, such as robotics, virtual reality (VR), and biofeedback systems, to address the neurocognitive deficits that contribute to the alarmingly high reinjury rates (9–29%) observed in young athletes post-ACLR. These deficits include impaired proprioception, motor control, and psychological factors like fear of reinjury. The methodology employed involves a narrative review of peer-reviewed literature from databases including PubMed, Scopus, and Web of Science. The synthesis of findings underscores the importance of holistic rehabilitation approaches, including targeted proprioceptive exercises, dual-task drills, and immersive VR training, in enhancing sensorimotor integration, decision-making, and athlete confidence. Furthermore, this review highlights the critical need for long-term monitoring and interdisciplinary collaboration between neuroscientists, physiotherapists, and engineers to refine rehabilitation protocols and ensure sustained recovery. By leveraging neuroplasticity and advanced technologies, the field can shift from a focus on purely physical restoration to comprehensive recovery models that significantly reduce reinjury risks and optimize athletic performance. Full article

Background: The ongoing conflict in Ukraine has forced numerous migrants into neighboring countries, many suffering from pre-existing or newly acquired physical and mental health conditions. Addressing these complex challenges in humanitarian settings requires innovative, evidence-based interventions that are cost-effective and easy to administer. Drawing upon research highlighting the vagus nerve’s role in regulating well-being, we hypothesized that vagal nerve activation could offer a promising therapeutic approach. Method: We conducted a proof-of-concept study in which 21 Ukrainian forced migrants were trained in a biofeedback-guided paced breathing intervention designed to stimulate the vagus nerve and promote self-regulation of stress response systems. Changes in pain perception, perceived stress, blood pressure, and heart rate were assessed before and after the vagal breathing intervention using a t-test. Correlations were examined at baseline. Results: Statistically significant improvements were observed in all measures except systolic blood pressure, providing preliminary evidence for the efficacy of vagal nerve activation in alleviating stress-related health symptoms. Conclusions: This study demonstrates the feasibility and therapeutic potential of a vagal nerve-activating intervention in a humanitarian setting. These findings warrant replication in larger, controlled trials. If substantiated, this low-cost, scalable intervention could help mitigate health burdens among forced migrant populations worldwide. Full article

Reliable acoustic coupling in a non-handheld mode and reducing the form factor of electronics are specific challenges in making ultrasound wearable. Applications relying on a large field of view (such as tracking of large muscles) induce a need for a large element count to achieve high image quality. In our work, we developed a 256-element linear array for imaging of abdominal muscles with four integrated custom-developed 8:32 multiplexer Integrated Circuits (ICs), allowing the array to be driven by our compact 32 ch electronics. The system is optimized for flexible use in R&D applications and allows adjustable transmit voltages (up to +/−100 V), arbitrary delay patterns, and 12-bit analog-to-digital conversion (ADC) with up to 50 MSPS and wireless (21.6 MBit/s) or USB link. Image metrics (SLL, FWHM) were very similar to a fully populated array driven with a 256 ch system. The contrast allowed imaging of lesions down to 7 cm in the phantom. In a first in-vivo study, we demonstrated reliable acoustic contact even during exercise and were able to visualize deep abdominal muscles such as the TrA. In combination with a muscle tracking algorithm, the change of thickness of the TrA during SSE could be monitored, demonstrating the potential of the approach as biofeedback for physiotherapy training. Full article

Background and Objectives: The aim of this study was to compare the effects of pelvic floor muscle contraction training (PFMCT) using verbal education, digital vaginal palpation (DVP), or perineometer on the common errors made during pelvic floor muscle contraction (PFMC) in women. Materials and Methods: A total of 48 women participated, and they were randomly assigned to three groups (Group I: PFMCT with verbal education, n = 16; Group II: PFMCT with DVP, n = 16; and Group III: PFMCT with perineometer, n = 16). Participants who had not previously received PFMCT were evaluated for pelvic floor muscle strength using the Modified Oxford Scale (MOS), and pelvic floor muscle activation was assessed with electromyographic biofeedback (EMG-BF). Possible errors during pelvic floor muscle contraction (gluteal, adductor and/or abdominal muscle contractions, stop breathing (breath holding), enhanced inhaling, and straining) were evaluated through inspection, palpation, or EMG-BF. After pre-training evaluations, all participants received training on pelvic floor. After this general training, each group received PFMCT using the specific training method for their group. After the training, the same evaluations were repeated. The sessions were conducted one-on-one and lasted for an average of one hour. Results: After the training, MOS values increased in Group II and Group III, while EMG-BF values only increased in Group II (p < 0.05). The number of incorrect movements during PFMC decreased after the training in all three groups (p < 0.05). The abdominal muscle contraction value monitored by EMG-BF only decreased in Group II (p < 0.05). Conclusions: Our study demonstrated that the PFMCT applied using the DVP method was more effective in creating more accurate and stronger muscle contractions and reducing common errors when compared to pre- and post-training values. Significant differences were observed between the groups in terms of performance improvements, with Group II showing the most notable progress. These results support the potential for DVP to yield better outcomes when used in PFMT. Full article

Breast cancer survivors experience numerous chronic symptoms linked to autonomic dysfunction including anxiety, stress, insomnia, menopausal symptoms, and cognitive impairment. Effective non-pharmacological solutions to address these are currently lacking. Methods: Our three-armed longitudinal randomized controlled trial assessed the effectiveness of a 4-week remote smartphone-based heart rate variability biofeedback intervention which involved daily paced breathing at 6 breaths p/min; active (12 breaths p/min) and waitlist controls were included. Heart rate variability and self-reported cancer-related symptoms were assessed at baseline, post-, and 6 months-post intervention. Participants were 60 UK-based women with primary breast cancer history (6 to 60 months post-active treatment). Results: The intervention group showed significant increases in low-frequency heart rate variability over time (F (4, 103.89) = 2.862, p = 0.027, d = 0.33), long-lasting improvement in sleep quality (F (4, 88.04) = 4.87, p = 0.001, d = 0.43) and cessations in night sweats (X² (2, N = 59) = 6.44, p = 0.04, Cramer’s V = 0.33), and reduced anxiety post-intervention compared to the active and waitlist controls (F (4, 82.51) = 2.99, p = 0.023, d = 0.44). Other findings indicated that the intervention and active control participants reported lasting improvements in cognitive function, fatigue, and stress-related symptoms (all ps < 0.05). The waitlist group reported no symptom changes across time. Conclusion: Heart rate variability biofeedback is a feasible intervention for addressing diverse chronic symptoms commonly reported by breast cancer survivors. Full article