Physiological Fatigue Research Articles

FatigueSense: Multi-Device and Multi-Modal Wearable Sensing for Detecting Mental Fatigue

Mental fatigue is a crucial aspect that has gained attention across various disciplines due to its impact on overall well-being. While previous research has explored the use of wearable devices for detecting mental fatigue, limited investigation has been conducted into the effectiveness of these devices in different body positions or in multi-device setups. To address this, our study utilizes a unique public dataset containing over 13 hours of sensor data collected across 36 sessions, with four wearable devices (Earable, Chestband, Wristband, and Headband). We propose several machine learning-based approaches to assess both psychological and physiological mental fatigue levels in a multimodal and multi-device environment. Specifically, we introduce device type-specific approaches (trained and tested on a single device) and multi-device approaches (trained and tested on multiple devices) for mental fatigue inference tasks. Our findings show that device type-specific models perform well, with AUC scores ranging from 0.63 to 0.69 for psychological and from 0.74 to 0.80 for physiological mental fatigue. The multi-device approach shows improved performance for psychological mental fatigue (AUC of 0.69 to 0.74) and physiological mental fatigue (AUC of 0.81 to 0.88). Hence, this study presents a unique and in-depth analysis of detecting mental fatigue with wearables, demonstrating the potential of machine learning-based approaches in multi-device and multimodal setups that are prevalent in today’s emerging lifestyles.

Effect of a multicomponent exercise program focused on multivariable fatigue improvement versus standard care for glenohumeral instability: MoveUS study protocol

BackgroundGlenohumeral instability is a highly prevalent pathology; however, there are problems in defining it. Traditionally, structural problems such as labral injury or bone loss in the glenoid cavity and/or humeral side were considered the main causes; but recently, it has been seen that motor control plays a very relevant role. This means that currently, there is a disparity of action protocols, and the treatment of this pathology is a great challenge.AimThe primary aim of this study is to evaluate the effectiveness of a supervised multicomponent therapeutic exercise program in reducing multivariable fatigue in patients with instability of the glenohumeral joint.MethodsA single-blind randomized controlled trial will be carried out, in which 108 adult patients who have suffered at least one episode of glenohumeral instability in the last year will be recruited by the Department of Traumatology and Rehabilitation of Axarquia Hospital (Málaga). Patients will be randomized to the intervention group, which will carry out a multicomponent therapeutic exercise program supervised by physiotherapists (MoveUS Program); or to the control group, which will receive the usual care. All subjects will be evaluated at baseline, mid-treatment, after the intervention, and three months later at the follow-up. In these evaluations, range of movement, maximum peak of isometric force, kinematic, physiological, and psychometric fatigue, return to activity, motor control, and number of recurrences will be assessed; as well as the quality of life measured through the Western Ontario Shoulder Instability Index, which will be the main outcome variable. A multivariate analysis will be performed through a statistical program to better determine the factors that could influence the results.DiscussionThis study aims to determine if therapeutic exercise supervised by physiotherapists is capable of reducing multivariable fatigue, reducing the number of recurrences, and improving quality of life; to be able to implement it in the future in public and private clinics since materials are available and physiotherapist have enough skills in the field of therapeutic exercise, so it is expected to be a quality tool in the approach to glenohumeral instability.RegistrationRegistry: ClinicalTrials.gov. Number: NCT05443295. Date: 01/07/2022.

Physiological and Neuromuscular Fatigue after 3-Minute Lateral Shuffle Movement at Different Speeds and Distances

Physiological and Neuromuscular Fatigue after 3-Minute Lateral Shuffle Movement at Different Speeds and Distances

Modern concepts of chronic fatigue syndrome: diagnosis and differential diagnosis with other variants of asthenic syndrome

Chronic fatigue is one of the most common syndromes in the clinical practice of medical doctors of various specialties. However, issues of criteria for distinguishing chronic fatigue from physiological fatigue, differential diagnosis of reactive asthenia, secondary fatigue syndrome and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) as a distinct nosological form can be challenging for physicians. The provision of care to patients with ME/CFS is negatively impacted by the lack of accurate and up-to-date knowledge about the disease among healthcare professionals. Even if doctors are compassionate, they often do not know how to make a diagnosis or what can be done to improve the well-being of patients. Currently, this problem is especially relevant due to the increased risk of developing ME/CFS after suffering from a new coronavirus infection, COVID-19. This article presents a modern approach to the diagnosis of ME/CFS, set out in consensus recommendations that were developed in 2021 independently by groups of experts on the diagnosis and treatment of this disease in European countries and the USA, and taking into account the recommendations of domestic specialists.

A Machine Learning–Based Ergonomic Assessment of Wireless Hand Control System for Lower‐Limb Disabled Tractor Operators and Abled Female Agricultural Workers

ABSTRACTTractor being the most used power source for agricultural operations needs hand control (HC) and foot control (FC) to maneuver it. FCs restrict lower‐limb disabled agricultural workers from participating in tractor operation, and high requirement of actuation forces to operate FCs may create overexertion and early fatigue to female agricultural workers. Therefore, a sensor‐based HC system has been developed to assist them in tractor operation with minimal actuating force. This study focuses on ergonomic assessment of the HC system to assess the suitability for the abled and disabled agricultural workers, including physiological, psychophysical, and muscle fatigue parameters. Heart rate (HR) of abled male and female, and disabled male and female was observed in the range of 83–118, 85–117, 93–118, and 92–114 beats/min, respectively, during tractor operation. Energy expenditure rate (EER) during tractor operation with FCs (9.7–17.4 kJ/min) was observed higher than with the HC system (7.3–16.5 kJ/min). Body parts discomfort was observed highest for the right hand of all the subjects (4.9–5.3) and maximum overall discomfort was experienced by abled females during the operation with FCs (5.4) as they have to exert higher force. The root mean square (RMS) value of the electromyography signal obtained for extensor digitorum muscle was found to be higher for all the subjects and with both HC and FC (abled male, 17.37–40.43 µV; abled female, 14.76–45.29 µV; disabled male, 15.49–40.23 µV; disabled female, 30.32–54.29 µV) than other upper arm muscles middle deltoid, flexor carpi radialis, and brachioradialis. Muscle workload for all the selected muscles of all the subjects was observed within the recommended limit during the tractor operation with a developed HC system (< 30%). Categorization of overall discomfort rating (ODR) of the subjects using HR, EER, and RMS through machine learning algorithms such as k‐nearest neighbor (KNN), random forest classifier, and support vector machine predicted the ODR with accuracies in the range of 77%–83%. KNN algorithm was found to be most accurate with prediction accuracy of 83%. The developed HC system provides assistantship to the lower‐limb disabled agricultural workers (1%–100% disability of lower limbs) and allows female workers to operate the tractor with minimal physical exertion.

Dynamic evolution of high-speed railway driver fatigue across scheduling shifts – a simulator study in China

ABSTRACT Scheduling significantly contributes to fatigue among high-speed rail (HSR) drivers, impacting both driving performance and safety. This study aims to analyse distinctiveness and evolutionary patterns of driver fatigue across different scheduling shifts, leveraging an HSR simulator and wearable devices. Through an extensive statistical examination, differences in most heart rate variability features were identified across shifts. The evolution of self-reported fatigue and physiological fatigue was investigated using a Markov chain and a hidden Markov model (HMM) that is extended using softmax regression, respectively. Results indicated a similarity in the initial fatigue state distribution and evolution trends across shifts, albeit with varying degrees of fluctuation. Morning shifts exhibited a higher likelihood of fatigue accumulation. The study revealed that even adequate pre-rest did not entirely counterbalance the impact of circadian rhythms. These findings may contribute to comprehending the temporal dynamics of driver fatigue evolution and offer insights for optimizing driver scheduling practices.

Wearable Sensors for Healthcare of Industrial Workers: A Scoping Review

Background and Objectives: This scoping review evaluates the use of wearable sensor technologies for workplace safety and health monitoring in industrial settings. The aim is to synthesize evidence on the impact of these sensors and their application in high-risk environments. Materials and Methods: Following the PRISMA guidelines, a systematic search across four international electronic databases yielded 59 studies, of which 17 were included in the final review. The selection criteria involved studies that specifically utilized wearable sensors to monitor various health and environmental parameters relevant to industrial workers. Results: The analysis categorizes wearable technologies into five distinct groups based on their function: gas monitoring technologies, heart rate and physiological data collection, fatigue and activity monitoring, comprehensive environmental and physiological monitoring, and advanced sensing and data collection systems. These devices demonstrated substantial benefits in terms of early detection of health risks and enhancement of safety protocols. Conclusions: The review concludes that wearable sensor technologies significantly contribute to workplace safety by providing real-time, data-driven insights into environmental hazards and workers’ physiological status, thus supporting proactive health management practices in industrial settings. Further research is recommended to address the challenges of data privacy, sensor reliability, and cost-effective integration to maximize their potential in occupational health safety.

The Impact of Pressure Training on the Performance of Semi-Professional Female Rugby League Players.

The aim of this study was to examine the effect of pressure training on the performance of semi-professional female rugby league athletes. Using a within-subjects design, 16 female athletes (19.9 ± 3.4 years) performed a passing accuracy task under three conditions; (1) a control condition; (2) a physiological fatigue condition; and (3) a threat of consequence condition. Passing performance, perceived pressure, rate of perceived exertion (RPE), and self-confidence were assessed. A significant main effect of conditions was found for rate of perceived exertion (p < 0.001), self-confidence (p < 0.028), and perceived pressure (p = 0.011). There was no main effect of condition on passing performance. Post hoc comparisons revealed that RPE was significantly higher in the physiological fatigue condition when compared to the control (p = 0.009) and threat of consequence conditions (p < 0.001). Perceived pressure was significantly higher in the threat of consequence condition compared to the control condition (p = 0.037). The main findings of this study are that (1) passing performance was not impacted by pressure training conditions, and (2) threats of consequences are an effective manipulation to generate pressure in female semi-professional rugby league players. These results offer nuanced insights into the impact of pressure generation in training environments for female semi-professional rugby league athletes.

The Impact of Physiological and Psychological Fatigue on Work Efficiency: A Case Study of Parcel Sorting Work.

The popularity of online shopping in China has increased significantly, creating new development opportunities for the express delivery industry. However, the rapid expansion of the express industry has also created challenges in the parcel sorting process. The demanding nature of parcel sorting work, which is characterized by intense and prolonged repetitive tasks, makes individuals particularly vulnerable to the effects of fatigue. Fatigue is a complex condition that encompasses both physiological and psychological exhaustion. It often results in reduced energy levels and diminished functionality, significantly impacting an individual's performance at work and their overall well-being. This study aimed to investigate how physiological and psychological fatigue affects sorting efficiency and to identify appropriate rest periods that will allow employees to maintain their performance levels. The research involved fifteen participants who took part in a 60 min continuous sorting experiment and a similar experiment with scheduled breaks. During both trials, we collected data on participants' electromyography (EMG) and electrodermal activity (EDA), as well as subjective fatigue ratings (RPE). Signal features such as the median frequency (MF) of EMG and the skin conductance level (SCL) were analyzed to assess physiological and psychological fatigue, respectively. The results show that physiological fatigue mainly affects sorting efficiency in the first 30 min, while psychological fatigue becomes more influential in the following half-hour period. In addition, subjective fatigue levels during the first 30 min are primarily determined by psychological factors, while beyond that point, both physiological and psychological fatigue contribute to subjective fatigue. Rest periods of 415-460 s, based on EDA recovery times, effectively support sorting efficiency and participants' recovery. This study highlights the complex ways in which fatigue affects parcel sorting performance and provides valuable theoretical and practical insights for establishing labor quotas and optimizing work schedules in the parcel sorting industry.

Update: Delayed Onset Muscle Soreness (DOMS) – Muscle Biomechanics, Pathophysiology and Therapeutic Approaches

The term Delayed Onset Muscle Soreness (DOMS) refers to a complex injury entity which is based on ultrastructural injury patterns. The injury is usually harmless and heals within a few days without sequelae. However, at the time of the manifestation there are (sometimes considerable) performance limitations and the risk of possible secondary injuries is increased. Thus, prevention and treatment of DOMS, especially in high-performance sports, are of particular value. Insights into muscle biomechanics are necessary to understand the background and mechanisms of DOMS. The definition and classification of overload-related muscle injuries has not yet been uniformly determined. Fluid transitions between physiological, metabolic and neuromuscular fatigue as well as the actual occurrence of injuries with clinical symptoms make clear delineation difficult. The “Munich Classification” terms Delayed Onset Muscle Soreness (DOMS) as Type 1b muscle injury, “delayed onset muscle pain”. The central target of prevention of DOMS is to prevent or alleviate the onset of the initial damage, known as “Exercise Induced Muscle Damage” (EIMD). In case of manifest DOMS, the intention is both to relieve the attendant symptoms and to promote rapid restoration of muscle function. In clinical practice as in scientific research, diverse procedures and interventions have proven valuable, whereby especially physical therapy procedures like cryotherapy, heat therapy or compression therapy show promising study results.

Medical intelligence using PPG signals and hybrid learning at the edge to detect fatigue in physical activities

The educational environment plays a vital role in the development of students who participate in athletic pursuits both in terms of their physical health and their ability to detect fatigue. As a result of recent advancements in deep learning and biosensors benefitting from edge computing resources, we are now able to monitor the physiological fatigue of students participating in sports in real time. These devices can then be used to analyze the data using contemporary technology. In this paper, we present an innovative deep learning framework for forecasting fatigue in athletic students following physical exercise. It addresses the issue of lack of precision computational models and extensive data analysis in current approaches to monitoring students’ physical activity. In our study, we classified fatigue and non-fatigue based on photoplethysmography (PPG) signals. Several deep learning models are compared in the study. Using limited training data, determining the optimal parameters for PPG presents a significant challenge. For datasets containing many data points, several models were trained using PPG signals: a deep residual network convolutional neural network (ResNetCNN) ResNetCNN, an Xception architecture, a bidirectional long short-term memory (BILSTM), and a combination of these models. Training and testing datasets were assigned using a fivefold cross validation approach. Based on the testing dataset, the model demonstrated a proper classification accuracy of 91.8%.

Performance and Fatigue Patterns in Elite Cyclists During 6 h of Simulated Road Racing.

Fatigue resistance is vital for success in elite road cycling, as repeated, intense efforts challenge the athletes' ability to sustain peak performance throughout prolonged races. The present study combined recurrent performance testing and physiological measures during 6 h simulated racing with laboratory testing to investigate factors influencing fatigue resistance. Twelve male national elite cyclists (25 ± 3 years; 76 ± 6 kg and VO2max of 5.2 ± 0.5 L/min) completed incremental power and maximal fat oxidation tests. Subsequently, they underwent field testing with physiological measures and fatigue responses evaluated through peak sprint power and 5 km time trial (TT) testing after 0, 2, 4, and 6 h of exercise. Peak power declined from 1362 ± 176 W in first sprint to 1271 ± 152 W after 2 h (p < 0.01) and then stabilized. In contrast, TT mean power gradually declined from 412 ± 38 W in the first TT to 384 ± 41 W in the final trial, with individual losses ranging from 2% to 14% and moderately correlated (r2 = 0.45) to accumulated exercise time above lactate threshold. High carbohydrate intake (~90 g/h) maintained blood glucose levels, but post-TT [lactate] decreased from 15.1 ± 2 mM to 7.1 ± 2.3 mM, while fat oxidation increased from 0.7 ± 0.3 g/min at 0 h to 1.1 ± 0.1 g/min after 6 h. The study identifies fatigue patterns in national elite cyclists. Peak sprint power stabilized after an initial impairment from 0 to 2 h, while TT power gradually declined over the 6 h simulated race, with increased differentiation in fatigue responses among athletes.

Mechanical evaluation of a threaded interference interlocking mechanism for angle-stable intramedullary nailing.

To assess the fatigue and load-to-failure mechanical characteristics of an intramedullary nail with a threaded interference design (TID) in comparison to a commercially available veterinary angle-stable nail with a Morse taper bolt design (I-Loc) of an equivalent size. 10 single interlocking screw/bolt constructs of TID and I-Loc implants were assembled using steel pipe segments and placed through 50,000 cycles of simulated, physiologic axial or torsional loading. Entry torque, postfatigue extraction torque, and 10th, 25,000th, and 50,000th cycle torsional toggle were assessed. Each construct was then loaded to failure in the same respective direction as fatigue testing. Four complete constructs of each design were then assessed using a synthetic bone analog with a 50-mm central defect via nondestructive torsional and axial loading followed by axial load to failure. All constructs were angle stable at all time points and withstood fatigue loading. Median insertional torque, extraction torque-to-insertion torque ratio, and torsional yield load were 33%, 33%, and 72.5% lower, respectively, for the TID interlocking screws. No differences in torsional peak load, torsional stiffness, axial yield load, axial stiffness, or axial peak load were identified. No differences in complete construct angle stability, torsional stiffness, axial peak load, axial stiffness, or axial yield load were identified. The TID had an inferior torsional yield load when compared to I-Loc implants but generated angle stability and sustained simulated physiologic fatigue loading. The TID may be a suitable mechanism for generating angle stability in interlocking nails.

Lateral Shuffle-Induced Fatigue Effects on Ankle Proprioception and Countermovement Jump Performance.

To determine how lateral shuffling/lateral shuffle (LS) -induced fatigue affects ankle proprioception and countermovement jump (CMJ) performance. Eighteen male college athletes performed 6 modes of a repeated LS protocol with 2 distances (2.5 and 5 m) and 3 speeds (1.6, 1.8, and 2.0 m/s). After LS, ankle inversion proprioception (AIP) was measured using the active movement extent discrimination apparatus (AMEDA). CMJ, blood lactate (BLa), heart rate (HR) and rating of perceived exertion (RPE) were measured before and after LS. The number of changes of direction (CODs) in each protocol was recorded. LS-induced fatigue was evident in BLa, HR and RPE (all p < 0.05), increasing with shorter shuffle distance and faster speed. RM-ANOVA showed a significant distance main effect on both AIP (p < 0.01) and CMJ (p < 0.05), but the speed main effect was only significant for CMJ (p ≤ 0.001), not AIP (p = 0.87). CMJ performance was correlated with BLa, HR and RPE (r values range from -0.62 to -0.32, all p ≤ 0.001). AIP was only correlated with CODs (r = -0.251, p < 0.01). These results suggested that in LS, shorter distance, regardless of speed, was associated with worse AIP, whereas subsequent CMJ performance was affected by both LS distance and speed. Hence, AIP performance was not related to physiological fatigue, but CMJ performance was. Results imply that LS affects processing proprioceptive input and producing muscular output differently, and that these two aspects of neuromuscular control are affected by physiological fatigue to varying degrees. These findings have implications for injury prevention and performance enhancement.

Injury prevention in professional soccer players: can re-warmup training be organized in the post-warmup and half-time during a soccer game in a short time?

Passive time, during the post-warmup and half-time, decreases athletes' performance and increases injury risk factors in the active phases of the soccer match. Objective. This narrative review aims to research and synthesize existing evidence to identify brief re-warmup strategies that may find applicability in the post-warmup and half-time of a soccer match. The analysis was conducted on PubMed, Web of Science, PEDro, SPORTDiscus and Google Scholar. Due to the lack of evidence, no temporal time was established, preferring most up-to-date articles. The data were synthesized in relation to the objectives, following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Our research yielded a total of 753 studies, 463 related to re-warmup, 136 articles on re-warmup in soccer, and 154 articles on re-warmup during half-time. Of these, 26 met the inclusion objectives and were included in this research. Our findings confirm that a re-warmup can mitigate the decremental effect of static rest on performance. From the studies considered, we have identified a work that emphasizes how a 1-minute warmup of high-intensity exercise at speed corresponding to 90% of VO<inf>2max</inf> can prevent decreases related to passive time, in sprint performance and muscle strength, as well as improve muscle temperature. These results could apply to both post-warmup and half-time scenarios of a soccer match. From this narrative review, it has been possible to highlight a one-minute high-intensity re-warmup that improved sprint performance, increased core temperature, and enhanced muscle activation, not leading to additional physiological or psychological fatigue.

Mental fatigue and chronic fatigue syndrome in clinical practice

Fatigue is an extremely disabling symptom both in healthy people and in various diseases. Physical fatigue is characterized by limitations in physical functioning, while mental/cognitive fatigue involves difficulties in concentrating and performing cognitive tasks. Mental and physical fatigue exist in both pathological and physiological fatigue. Fatigue is primarily an adaptive physiological process. It is a signal to have a rest and helps conserve energy to prevent injury, which can be useful after intense work, or when the body’s defenses need to be redistributed, for example, during infectious disease. It is important to distinguish between fatigue or tiredness and chronic fatigue syndrome in clinical practice. Chronic fatigue syndrome has multisystem manifestations and affects millions of people globally. Although the exact aetiology of chronic fatigue syndrome is uncertain, the studies point to neurological, immunological, autonomic and energy disorders. The main sings of chronic fatigue syndrome are debilitating fatigue that is worsened by activity, poor exercise tolerance, unrefreshing sleep and cognitive impairment. Reduced information processing speed is the most common cognitive impairment in chronic fatigue syndrome. Other manifestations include decreased reaction time, working memory, and attention. These symptoms must persist for at least 3–6 months for a diagnosis to be made. As there are no specific tests for chronic fatigue syndrome, a diagnosis can be established on the basis of a medical history and physical examination.Although there are no standards-based methods specific to chronic fatigue syndrome, clinicians can reduce the severity of symptoms using pharmacological and non-pharmacological treatment approaches that have proved their efficacy in clinical practice. In particular, nootropics are widely used in asthenic conditions and chronic fatigue syndrome. Fonturacetam is a nootropic drug that directly activates brain integration activities, promotes memory consolidation, and improves concentration and mental activity.

Which horticultural activities are more effective for children's recovery from stress and mental fatigue? A quasi-experimental study.

Studies have established the benefits of horticultural therapy and activities for human health and well-being. Nonetheless, limited research has been conducted on the potential restorative advantages and distinctions between different types of horticultural activities in terms of stress reduction. This study employed a quantitative research method to investigate the stress recovery benefits of five horticultural activities (flower arrangement, sowing and transplanting seeds, kokedama crafting, pressed flower card making, and decorative bottle painting with dried flowers) and one reference activity (short composition writing) for children. The experiment was conducted in a children's activity center's multi-purpose classroom with 48 elementary students aged 9-12 years. The subjects first took a stress test to induce stress and then engaged in horticultural activities for 20 min. Physiological stress was assessed using electrocardiograms and electroencephalograms as feedback indicators. Psychological and emotional changes were determined using the Positive and Negative Affect Schedule for Children and Self-Assessment Manikin scales. The results demonstrated that horticultural activities greatly reduced physiological fatigue, and their recovery benefits were significantly greater than those of the reference activity. The recovery effects from different horticultural activities were similar across physiological indicators, although flower arrangement and sowing and transplanting seeds exhibited relatively robust recovery benefits. The heart rate and α-EEG-based generalized estimating equation revealed that horticultural activities offered significantly better relative recovery at each time phase of operation than the reference activity, with girls showing a 3.68% higher relative recovery value than boys. Flower arrangement and kokedama crafting offered better physiological recovery for students with prior horticultural experience, and these two activities received the highest scores in terms of positive effects and the "pleasure" dimension. Students believed that participating in horticultural activities resulted in a noteworthy increase in personal confidence and a greater sense of achievement. The study suggests that horticultural activities that involve real and vibrant plants or natural materials and are more attractive have more stress-relieving benefits. We conclude that horticultural activities are beneficial leisure activities that aid in stress relief for children and that it is important to consider the attributes of activities when developing horticultural programs for elementary students.

The status and influencing factors of fatigue in kidney transplant recipients based on the theory of unpleasant symptoms: A cross-sectional study in China.

This study describes the incidence of fatigue in kidney transplant recipients and analyses the relationship between physiological factors, psychological factors, situational factors and fatigue in kidney transplant recipients. Fatigue, as a common symptom after kidney transplantation, is affected by many factors, but the influence of some factors on the fatigue of kidney transplant recipients is still controversial. This cross-sectional study was designed based on the theory of unpleasant symptoms. Our survey involved 307 participants attending the kidney transplant outpatient clinic of a tertiary Class A hospital (Changsha, Hunan, China). Data were collected between February and April 2021 using a structured questionnaire and electronic medical records. Data were analysed using IBM SPSS 25.0 (SPSS Inc.) RESULTS: It was found that the incidence of fatigue in kidney transplant recipients was 53.1%. According to the binary logistic regression analysis, sleep quality, hypokalemia, anxiety, depression and education level were independent risk factors for fatigue in kidney transplant recipients. The incidence of fatigue in kidney transplant recipients was high and was influenced by physical, psychological and situational factors. Clinical nurses should assess fatigue levels in a timely and multidimensional manner in clinical practice and provide effective and scientific guidance about fatigue self-coping and symptom management for kidney transplant recipients.

Optimization system for training efficiency and load balance based on the fusion of heart rate and inertial sensors

ObjectivesTo enhance the daily training quality of athletes without inducing significant physiological fatigue, aiming to achieve a balance between training efficiency and load. Design methodsFirstly, we developed an activity classification training model using the random forest algorithm and introduced the “effective training rate” (the ratio of effective activity time to total time) as a metric for assessing athlete training efficiency. Secondly, a method for rating athlete training load was established, involving qualitative and quantitative analyses of physiological fatigue through subjective fatigue scores and heart rate data. Lastly, an optimization system for training efficiency and load balance, utilizing multiple inertial sensors, was created. Athlete states were categorized into nine types based on the training load and efficiency ratings, with corresponding management recommendations provided. ResultsOverall, this study, combining a sports activity recognition model with a physiological fatigue assessment model, has developed a training efficiency and load balance optimization system with excellent performance. The results indicate that the prediction accuracy of the sports activity recognition model is as high as 94.70%. Additionally, the physiological fatigue assessment model, utilizing average relative heart rate and average RPE score as evaluation metrics, demonstrates a good overall fit, validating the feasibility of this model. ConclusionsThis study, based on relative heart rate and wearable devices to monitor athlete physiological fatigue, has developed a balanced optimization system for training efficiency and load. It provides a reference for athletes’ physical health and fatigue levels, offering corresponding management recommendations for coaches and relevant professionals.

A novel deep-learning model based on τ-shaped convolutional network (τNet) with long short-term memory (LSTM) for physiological fatigue detection from EEG and EOG signals.

In recent years, fatigue driving has become the main cause of traffic accidents, leading to increased attention towards fatigue detection systems. However, the pooling and strided convolutional operations in fatigue detection algorithm based on traditional deep learning methods may led to the loss of some useful information. This paper proposed a novel -shaped convolutional network ( ) aiming to address this issue. Unlike traditional network structures, incorporates the operations of upsampling features and concatenating high- and low-level features, enabling full utilization of useful information. Moreover, considering that the fatigue state is a mental state involving temporal evolution, we proposed the novel long short-term memory (LSTM)- -shaped convolutional network (LSTM- ), a parallel structure composed of LSTM and for fatigue detection, where extracts time-invariant features with location information, and LSTM extracts long temporal dependencies. We compared LSTM- with six competing methods based on two datasets. Results showed that the proposed algorithm achieved higher classification accuracy than the other methods, with 94.25% on EEG data (binary classification) and 82.19% on EOG data (triple classification). Additionally, the proposed algorithm exhibits low computational cost, good training stability, and robustness against insufficient training. Therefore, it is promising for further implementation of fatigue online detection systems.