Different subtypes of chronic fatigue in childhood cancer survivors: A DCCSS LATER study.

INTRODUCTION: The aim of the current study was to investigate whether subtypes of chronic fatigue (CF) can be identified in childhood cancer survivors (CCS), and if so, to determine the characteristics of participants with a specific subtype. METHODS: Participants were included from the nationwide DCCSS LATER cohort. The Checklist Individual Strength (CIS) was completed to assess fatigue. Participants with CF (scored ≥35 on the fatigue severity subscale and indicated to suffer from fatigue for ≥6 months) were divided into subgroups using two-step cluster analysis based on the CIS concentration, motivation, and physical activity subscales. Differences between groups on demographics, psychosocial, lifestyle, and treatment-related variables were determined using ANOVA and chi-square analyses (univariable) and multinomial regression analysis (multivariable). RESULTS: A total of 1910 participants participated in the current study (n = 450 with CF; n = 1460 without CF). Three CF subgroups were identified: Subgroup 1 (n = 133, 29% of participants) had CF with problems in physical activity; Subgroup 2 (n = 111, 25% of participants) had CF with difficulty concentrating; and Subgroup 3 (n = 206, 46% of participants) had multi-dimensional CF. Compared to Subgroup 1, Subgroup 2 more often reported sleep problems, limitations in social functioning, and less often have more than two comorbidities. Subgroup 3 more often reported depression, sleep problems, a lower self-esteem, and limitations in social functioning and a lower educational level compared to Subgroup 1. CONCLUSION: Different subgroups of CCS with CF can be identified based on fatigue dimensions physical activity, motivation and concentration. Results suggest that different intervention strategies, tailored for each subgroup, might be beneficial.

Multidisciplinary analysis of cancer-related fatigue at the time of diagnosis: preliminary results of the BIOCARE FActory cohort.

PURPOSE: Cancer-related fatigue (CRF) is a common side effect of cancer and cancer treatment that significantly impairs the quality of life and can persist for years after treatment completion. Although fatigue is often associated with cancer treatment, it is also a result of the disease itself, even before intervention. CRF at the time of diagnosis may affect treatment timing or completion and is a consistent predictor of post-treatment fatigue at any time. The mechanisms underlying CRF are multidimensional and not well understood, particularly at the time of diagnosis. METHODS: Sixty-five breast cancer patients at the time of diagnosis were included. The participants completed self-assessment questionnaires about CRF, sleep disturbances, and emotional symptoms and wore an accelerometer to assess levels of spontaneous physical activity and sleep quality. During the experimental session, the participants underwent cognitive, neuromuscular, and exercise metabolism evaluations. RESULTS: Using augmented backward elimination regression, this study found that emotional symptoms and perceived sleep disturbances were the strongest predictors of CRF (adjusted r2 = 0.51). Neuromuscular fatigability and sleep disturbance were also associated with physical dimensions, whereas cognitive performance was associated with cognitive dimensions. CONCLUSION: At the time of diagnosis, emotional and cognitive dimensions are over-represented compared to the general population, and specific subdimensions have specific predictors that support the idea of distinct mechanisms. Evaluating CRF subdimensions and their potential mechanisms at the time of diagnosis would be particularly relevant for identifying high-risk patients and offering them appropriate interventions. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov (NCT04391543) in May, 2020.

Relationship between physical fatigue and mental fatigue based on multimodal measurement under different load levels.

Based on multimodal measurement methods of NASA task load index (NASA-TLX), task performance, surface electromyography (sEMG), heart rate (HR), and functional near-infrared spectroscopy (fNIRS), this study conducted experimental measurements and analyses under 16 different load levels of physical fatigue and mental fatigue combination conditions. This study observed the interaction between physical fatigue and mental fatigue at different levels, and at the subjective level, the effect of physical fatigue on mental fatigue was greater than that of mental fatigue on physical fatigue. Secondly, the results of fNIRS analysis showed that the premotor cortex is affected by physical fatigue, and the dorsolateral prefrontal cortex is affected by mental fatigue. Finally, this study constructed a fatigue classification model with an accuracy of 95.3%, which takes multimodal physiological data as input and 16 fatigue states as output. The research results will provide a basis for fatigue analysis, evaluation, and improvement in complex working situations.

Based on multimodal measurement methods of NASA-TLX, task performance, sEMG, HR, and fNIRS, this study illustrated the relationship between physical fatigue and mental fatigue, and proposed a classification method for different fatigue situations.

Effect of Globin Digests on Physical Fatigue in Mice.

Globin digest (GD) inhibits dietary hypertriglyceridemia; however, its effects on physical fatigue remain unknown. Therefore, this study aimed to investigate the potential anti-fatigue effects of GD. Repeated administration of GD and valine (Val)-Val-tyrosine (Tyr)-proline (Pro), a component of GD, for five days prevented the forced walking-induced decrease in locomotion. Furthermore, GD treatment reversed the forced walking-induced increase in blood lactate levels in mice and increased phosphorylated AMP-activated protein kinase (p-AMPK) in the soleus muscle, suggesting that the anti-fatigue effect of GD involves AMPK activation in the soleus muscle through reduced blood lactate.

Monitoring Inattention in Construction Workers Caused by Physical Fatigue Using Electrocardiograph (ECG) and Galvanic Skin Response (GSR) Sensors.

Physical fatigue is frequent for heavy manual laborers like construction workers, but it causes distraction and may lead to safety incidents. The purpose of this study is to develop predictive models for monitoring construction workers' inattention caused by physical fatigue utilizing electrocardiograph (ECG) and galvanic skin response (GSR) sensors. Thirty participants were invited to complete an attention-demanding task under non-fatigued and physically fatigued conditions. Supervised learning algorithms were utilized to develop models predicting their attentional states, with heart rate variability (HRV) features derived from ECG signals and skin electric activity features derived from GSR signals as data inputs. The results demonstrate that using HRV features alone could obtain a prediction accuracy of 88.33%, and using GSR features alone could achieve an accuracy of 76.67%, both through the KNN algorithm. The accuracy increased to 96.67% through the SVM algorithm when combining HRV and GSR features. The findings indicate that ECG sensors used alone or in combination with GSR sensors can be applied to monitor construction workers' inattention on job sites. The findings would provide an approach for detecting distracted workers at job sites. Additionally, it might reveal the relationships between workers' physiological features and attention.

A Physical Fatigue Evaluation Method for Automotive Manual Assembly: An Experiment of Cerebral Oxygenation with ARE Platform.

Due to the complexity of the automobile manufacturing process, some flexible and delicate assembly work relies on manual operations. However, high-frequency and high-load repetitive operations make assembly workers prone to physical fatigue. This study proposes a method for evaluating human physical fatigue for the manual assembly of automobiles with methods: NIOSH (National Institute for Occupational Safety and Health), OWAS (Ovako Working Posture Analysis System) and RULA (Rapid Upper Limb Assessment). The cerebral oxygenation signal is selected as an objective physiological index reflecting the human fatigue level to verify the proposed physical fatigue evaluation method. Taking auto seat assembly and automobile manual assembly as an example, 18 group experiments were carried out with the ARE platform (Augmented Reality-based Ergonomic Platform). Furthermore, predictions of metabolic energy expenditure were performed for experiments in Tecnomatix Jack. Finally, it is concluded that the proposed physical fatigue evaluation method can reflect the human physical fatigue level and is more accurate than the evaluation of metabolic energy consumption in Tecnomatix Jack because of the immersion that comes with the AR devices and the precision that comes with motion capture devices.

Acute Effects of Fatigue on Cardiac Autonomic Nervous Activity.

The onset of fatigue disrupts the functioning of the autonomic nervous system (ANS), potentially elevating the risk of life-threatening incidents and impairing daily performance. Previous studies mainly focused on physical fatigue (PF) and mental fatigue (MF) effects on the ANS, with limited knowledge concerning the influence of physical-mental fatigue (PMF) on ANS functionality. This study aimed to assess the immediate impact of PMF on ANS function and to compare its effects with those of PF and MF on ANS function. Thirty-six physically active college students (17 females) without burnout performed 60-min cycling exercises, AX-Continuous Performance Task (AX-CPT), and cycling combined with AX-CPT to induce PF, MF, and PMF respectively. Subjective fatigue levels were measured using the Rating of Perceived Exertion scale and the Visual Analog Scale-Fatigue. Heart rate variability was measured before and after each protocol to assess cardiac autonomic function. The proposed tasks successfully induced PF, MF, and PMF, demonstrated by significant changes in subjective fatigue levels. Compared with baseline, PMF decreased the root mean square of successive differences (RMSSD) between normal heartbeats (P < 0.001, d = 0.50), the standard deviation of normal-to-normal RR intervals (SDNN) (P < 0.01, d = 0.33), and the normalized high-frequency (nHF) power (P < 0.001, d = 0.32) while increased the normalized low-frequency (nLF) power (P < 0.001, d = 0.35) and the nLF/nHF ratio (P < 0.001, d = 0.40). Compared with MF, PMF significantly decreased RMSSD (P < 0.001, η2 = 0.431), SDNN (P < 0.001, η2 = 0.327), nLF (P < 0.01, η2 = 0.201), and nHF (P < 0.001, η2 = 0.377) but not the nLF/nHF ratio. There were no significant differences in ΔHRV (i.e., ΔRMSSD, ΔSDNN, ΔnLF/nHF, ΔnLF, and ΔnHF), heart rate, and training impulse between PF- and PMF-inducing protocols. Cognitive performance (i.e., accuracy) in AX-CPT during the PMF-inducing protocol was significantly lower than that during the MF-inducing protocol (P < 0.001, η2 = 0.101). PF and PMF increased sympathetic activity and decreased parasympathetic activity, while MF enhanced parasympathetic activity.

Heart Rate Variability-Based Subjective Physical Fatigue Assessment.

Accurate assessment of physical fatigue is crucial to preventing physical injury caused by excessive exercise, overtraining during daily exercise and professional sports training. However, as a subjective feeling of an individual, physical fatigue is difficult for others to objectively evaluate. Heart rate variability (HRV), which is derived from electrocardiograms (ECG) and controlled by the autonomic nervous system, has been demonstrated to be a promising indicator for physical fatigue estimation. In this paper, we propose a novel method for the automatic and objective classification of physical fatigue based on HRV. First, a total of 24 HRV features were calculated. Then, a feature selection method was proposed to remove useless features that have a low correlation with physical fatigue and redundant features that have a high correlation with the selected features. After feature selection, the best 11 features were selected and were finally used for physical fatigue classifying. Four machine learning algorithms were trained to classify fatigue using the selected features. The experimental results indicate that the model trained using the selected 11 features could classify physical fatigue with high accuracy. More importantly, these selected features could provide important information regarding the identification of physical fatigue.

A Novel Physical Fatigue Assessment Method Utilizing Heart Rate Variability and Pulse Arrival Time towards Personalized Feedback with Wearable Sensors.

This paper proposes a novel method for physical fatigue assessment that can be applied in wearable systems, by utilizing a set of real-time measurable cardiovascular parameters. Daylength measurements, including a morning test set, physical exercise during the day, and an afternoon test set were conducted on 16 healthy subjects (8 female and 8 male). To analyze cardiovascular parameters for physical fatigue assessment, electrocardiography, pulse wave and blood pressure were measured during the test sets. The fatigue assessment questionnaire score, reaction time, countermovement jump height and hand grip strength were also measured and used as reference parameters. This study demonstrates that (i) the compiled test battery can selectively assess the rested vs. physically-fatigued states; (ii) the obtained linear support-vector machine, trained using the heart rate variability based parameter (F-score 0.842, accuracy 0.813) and pulse arrival time based parameter (F-score 0.875, accuracy 0.875) shows a promising ability to classify between the physically mildly fatigued and significantly fatigued states. Despite the somewhat limited study group size, the results of the study are unique and provide a significant advancement on the existing physical fatigue assessment methods towards a personalized and continuous real-time fatigue monitoring system with wearable sensors.

Influence of night vision goggles with white and green phosphor screens on selected parameters of the eye and fatigue.

In modern aviation, in particular in the military context, increasingly many aviation tasks are performed at night. To improve the safety of night flights, night vision goggles (NVGs) are commonly used. This study aimed to examine whether changes in ophthalmic parameters during NVGs use vary depending on phosphor screen type (green or white coded as P43 and P45 respectively). Thirteen participants were studied during a 2-h visual task in a night vision laboratory. Before and after NVGs use, we examined visual acuity, pachymetry, critical flicker-frequency thresholds, stereoscopic and contrast vision. During the use of NVGs, visual acuity, intra-ocular pressure and eye refraction were measured. We found no difference in visual performance between NVGs with green and white phosphor screens; however, NVGs use in general may lead to subjective eye fatigue, neck pain and headaches associated with the time of wearing and the weight of the helmet with additional equipment attached. Practitioner summary Night vision goggles (NVGs), widely used to improve the safety of night flights, were examined according to the applied type of the phosphor screen. There was no difference in visual performance between a white and green phosphor screens; however, NVGs and helmet manufacturers should strive to design these devices to be as lightweight as possible. Abbreviations: ANOVA: analysis of variance; CCT: central corneal thickness; CFF: critical flicker frequency; CNS: central nervous system; CS: contrast sensitivity; FOV: field-of-view; I2: image intensifier; IOP: intra-ocular pressure; NVGs: night vision goggles; SV: stereoscopic vision; VA: visual acuity; VAS: visual analog scale.

Effects of Bushen Yiyuan recipe on testosterone synthesis in Leydig cells of rats with exercise-induced low serum testosterone levels.

CONTEXT: Bushen Yiyuan recipe (BYR) is an effective Chinese prescription with antifatigue and antioxidation effects. OBJECTIVE: The effects of BYR on testosterone synthesis in rat Leydig cells with exercise-induced low serum testosterone levels (EILST) are assessed. MATERIALS AND METHODS: Thirty-two Sprague-Dawley rats were chronically trained for 6 weeks to establish an EILST model. EILST rats were divided into model (physiological saline), EFE (700 mg/kg ethanol extract of Epimedii folium, the dried leaves of Epimedium brevicornu Maxim [Berberidaceae]), and BYR groups (350 and 700 mg/kg) for 6 weeks. Expression of HMG-CoA, LDL-R, SR-BI, STAR and CYP11A1 were quantified by RT qPCR and Western blots. RESULTS: Compared with the model group (115.52 ± 13.05 µg/dL; 67.83 ± 14.29; 0.32 ± 0.04; 0.33 ± 0.02; 0.38 ± 0.01), serum testosterone, testosterone/cortisol ratio, HMG-CoA, STAR and CYP11A1 relative protein expression significantly increased in low-dose BYR (210.60 ± 5.08 µg/dL; 119.38 ± 13.02; 0.47 ± 0.01; 0.46 ± 0.03; 0.46 ± 0.02), high-dose BYR (220.57 ± 14.71 µg/dL; 124.26 ± 14.79; 0.49 ± 0.02; 0.42 ± 0.03; 0.51 ± 0.02), and EFE groups (206.83 ± 5.54 µg/dL; 119.53 ± 25.04; 0.45 ± 0.02; 0.42 ± 0.02; 0.41 ± 0.02) (all p < 0.01, except for CYP11A1 in EFE group). HMG-CoA, STAR and CYP11A1 mRNA relative expression significantly increased in low-dose and high-dose BYR group compared to model group (all p < 0.01). CONCLUSIONS: BYR affects endogenous cholesterol synthesis and testosterone synthesis to prevent and treat EILST levels in rats. It can improve the body's sports ability.

The effect of flaxseed on physical and mental fatigue in children and adolescents with overweight/obesity: a randomised controlled trial.

Anti-inflammatory agents such as long-chain n-3 fatty acids have been recognised to improve disease-related fatigue. We hypothesised that α-linolenic acid may also benefit in reduction of fatigue in low-grade inflammation such as overweight/obesity. Seventy-two healthy children and adolescents with BMI > 25 kg/m2 were randomised to flaxseed (n 38) and puffed wheat (n 34) groups. Participants consumed isoenergetic amounts of either 20 g/d flaxseed or 25 g/d puffed wheat for 4 weeks. Fatigue, mood feelings (depression, anxiety and stress), appetite, energy intake, weight, height and waist circumference were measured. Analysis was performed based on per-protocol and intention-to-treat (ITT) approaches. Consumption of flaxseed decreased mental fatigue and caused a significant between-group difference (P < 0·001). Although no significant change in physical and total score of fatigue was observed in either group, a significant between-group difference occurred due to a more remarkable change in these parameters in the flaxseed group. General fatigue, motivation, activity and mood feelings did not change significantly between groups. Flaxseed showed less benefit than puffed wheat on anthropometric measures as it caused a smaller increase in height (0·53 (sd 0·89) v. 1·09 (sd 0·87) cm, P = 0·03) and reduction in BMI (-0·25 (sd 0·63) v. -0·67 (sd 0·56) kg/m2, P = 0·01) than puffed wheat. Appetite and waist circumference decreased in both groups, but no significant difference was observed between groups. In ITT analysis, only alteration in mental fatigue was significant. In conclusion, consumption of flaxseed may improve mental fatigue in children with overweight/obesity. However, because of smaller increase in height, it is better to hinder administration of flaxseed during periods of growth.

Subgroups of patients undergoing chemotherapy with distinct cognitive fatigue and evening physical fatigue profiles.

PURPOSE: The purpose was to model cognitive fatigue and evening physical fatigue together to determine subgroups of patients with distinct cognitive fatigue AND evening physical fatigue profiles. Once these profiles were identified, differences among the subgroups in demographic and clinical characteristics, co-occurring symptoms, and quality of life outcomes were evaluated. METHODS: Oncology patients (n = 1332) completed self-report measures of cognitive fatigue and evening physical fatigue, six times over two cycles of chemotherapy. Latent profile analysis, which combined the two symptom scores, was done to identify subgroups of patients with distinct cognitive fatigue AND evening physical fatigue profiles. RESULTS: Three distinct profiles (i.e., Low [20.5%], Moderate [39.6%], and High [39.6%]) were identified. Compared to the Low class, patients in the High class were younger, female, and more likely to live alone and had a higher comorbidity burden and a lower functional status. In addition, these patients had a higher symptom burden and a poorer quality of life. CONCLUSION: Based on clinically meaningful cutoff scores, 80% of the patients in this study had moderate to high levels of both cognitive fatigue and evening physical fatigue. In addition, these patients experienced high levels of other common symptoms (e.g., anxiety, depression, sleep disturbance, and pain). These co-occurring symptoms and other modifiable characteristics associated with membership in the Moderate and High classes may be potential targets for individualized symptom management interventions.

The combination of physical and mental load exacerbates the negative effect of each on the capability of skilled soccer players to anticipate action.

This study examined the impact of combining physical and mental load on the anticipatory judgements of skilled soccer players. Sixteen players completed an 11vs11 video anticipation test in four counterbalanced conditions, each separated by 7 days. The baseline condition consisted of only the anticipation test. A physical load condition required participants to complete a simulated soccer protocol on a treadmill followed by the anticipation test. A mental load condition required participants to complete a 30-min Stroop test followed by the anticipation test. Finally, in the combined load condition, participants completed the physical load protocol alongside the mentally loading Stroop task followed by the anticipation test. Response accuracy, visual search behaviour and measures of effort were assessed throughout. Response accuracy decreased in the separate physical load and mental load conditions when compared to baseline and worsened further in the combined load condition. The reduction in response accuracy across experimental conditions coincided with an increase in the number of fixations when compared to the baseline condition. It is suggested that the separate sources of load impaired the players ability to allocate sufficient resources to task-relevant information leading to a reduction in anticipatory accuracy, and this was exacerbated in the combined load condition.

Physical and mental fatigue across the menstrual cycle in women with and without generalised anxiety disorder.

Subjective, disabling fatigue is a common complaint and a key feature of numerous medical conditions, and is a transdiagnostic feature of psychiatric disorders. Despite physical and mental fatigue being associated with functional impairment and reduced quality of life, little is understood about its underlying mechanisms or modulating factors. Women commonly experience exacerbation of other (non-fatigue related) psychiatric symptoms during the luteal phase of the menstrual cycle, and report greater fatigue prevalence compared to men. It is therefore plausible that subjective fatigue may similarly fluctuate across the menstrual cycle. Here we compared physical and mental fatigue in the early-follicular (lower ovarian hormones) and mid-luteal (higher ovarian hormones) phases of a single menstrual cycle, while controlling for sleep disruption, in women with (n = 18) and without (non-anxious; n = 20) generalised anxiety disorder (GAD). As expected, women with GAD reported greater physical and mental fatigue than healthy women. Further, although there were no changes in physical fatigue from the early-follicular to mid-luteal phases in both groups, mental fatigue in non-anxious women increased to levels equivalent to those experienced by their GAD counterparts in the mid-luteal phase. Although salivary levels of estradiol and progesterone increased from the early-follicular to mid-luteal phase, hormones did not significantly predict fatigue in either phase. These findings are consistent with the exacerbations of state anxiety and mood disturbance recognised to occur in the luteal phase of the menstrual cycle. We speculate that increased mental fatigue in the luteal phase may represent a vulnerable period for the development and maintenance of psychiatric disorders, potentially via compromised emotional regulation.

Effects of Fatigue on Balance Recovery From Unexpected Trips.

OBJECTIVE: The objective was to examine how physical fatigue and mental fatigue affected balance recovery from unexpected trips. BACKGROUND: Trips are the leading cause for occupational falls that are a multifactorial problem. Recognizing risk factors is the first step in accident control. Fatigue is one of the most common task-related risk factors for occupational falls. Fatigue typically can be divided into physical fatigue and mental fatigue, both of which are common in occupational settings. METHOD: One hundred eight young volunteers participated in the experiment. They were evenly divided into three groups: no fatigue group, physical fatigue group, and mental fatigue group. Each participant performed four walking trials on a linear walkway at their self-selected normal speed. The first three trials were normal walking trials. A trip was induced to participants in the fourth walking trial using a metal pole. Balance recovery from unexpected trips was characterized by trunk flexion and first recovery step measures. RESULTS: Recovery step length was smaller and maximum trunk flexion became larger in the mental fatigue group compared with those in the no fatigue group. Physical fatigue did not significantly affect trunk flexion and first recovery step measures. CONCLUSION: Mental fatigue increased the likelihood of loss of balance. Thus, mental fatigue could be a risk factor for trips and falls. To prevent trip-related falls, interventions should be adopted to prevent prolonged exposures to cognitively demanding activities in occupational settings.

[Ornitine-dependent mechanisms of muscle fatigue correction and recovery from physical activity]. / Ornitinzavisimye mekhanizmy korrektsii myshechnogo utomleniya i vosstanovleniya posle fizicheskikh nagruzok.

The article analyzes the literature data characterizing modern concepts of the mechanisms of muscle fatigue and metabolic features of recovery processes after exhausting loads. The significance of transient hyperammonium in the formation of the developed complex of fatigue manifestations in the central and peripheral links of motor units, its pathogenetic links with oxygen debt, lactacidosis, violation of ATP resynthesis, deficiency of energy-supplying substrates in working skeletal muscles, damage to muscle fibre structures, and dysfunction of various parts of the CNS is shown. The necessity of correction of hyperammoniemia associated with physical activity has been confirmed to reduce the speed of formation and expression of fatigue feeling, to reduce the risks of development of fatigue and overtraining states in sportsmen and to ensure effective course of recovery processes after exhausting physical activity. It was revealed that ornithine-containing preparations can be used for correction of post-load hyperammonium and acceleration of recovery processes. The data characterizing the high efficiency of L-ornitine-L-aspartate in sports medicine practice are presented.

Determinants of physical, affective, and cognitive fatigue during breast cancer therapy and 12 months follow-up.

Fatigue is common in cancer survivors but often insufficiently treated. Due to its complexity a one-size-fits-all treatment seems not appropriate. To gain more information on influencing factors and sub-dimensions of fatigue we investigated potential determinants and correlates of physical, affective, and cognitive fatigue in breast cancer survivors during and after adjuvant therapy. Within the follow-up of two randomized controlled trials physical, affective, and cognitive fatigue were repeatedly assessed during and up to 12 months after cancer therapy with the 20-item Fatigue Assessment Questionnaire in 255 breast cancer survivors. Determinants of the different fatigue dimensions over time were explored with linear mixed models. Chemotherapy appeared as significant precipitating factor for physical fatigue. However, type of cancer therapy had no impact on fatigue one year post-treatment. Obesity was significantly associated with increased physical fatigue throughout all time points (Δ=15.5 at 12 months) whereas exercise appeared to be beneficial (Δ = -6.3). In contrast, affective fatigue was significantly associated with poor social support and worries about the future. In addition, poor sleep quality and previous use of psychopharmaceuticals were significantly associated with physical, affective, as well as cognitive fatigue. Further, hot flashes were associated with increased physical and cognitive fatigue. In conclusion, the broad diagnosis 'fatigue' in cancer survivors needs to be recognized as a diversity of symptoms determined by specific characteristics and likely different etiologies. Taking potential influencing factors such as obesity, physical inactivity, sleep problems, hot flashes, lack of social support, or psychological disorders into consideration might enable a better, individually-tailored fatigue treatment.

Mental versus physical fatigue after subarachnoid hemorrhage: differential associations with outcome.

BACKGROUND AND PURPOSE: Fatigue is a major consequence of subarachnoid hemorrhage (SAH), but the specific characteristics are unclear. Our objective was to investigate the nature of post-SAH fatigue (mental or physical) and to determine the relationship with functional outcome in the chronic stage. Also, the possible influence of mood disorders and acute SAH-related factors [SAH type and external cerebrospinal fluid (CSF) drainage] on the presence of fatigue was investigated. METHODS: Patients with an aneurysmal SAH (aSAH) or angiographically negative SAH (anSAH) were assessed 3-10 years post-SAH (N = 221). Questionnaires were used to investigate mental and physical fatigue and mood. Functional outcome was examined with the Glasgow Outcome Scale Extended. Between-group comparisons and binary logistic regression analysis were performed. RESULTS: Frequencies of mental and physical fatigue were 48.4% and 38.5%, respectively, with prevalence of mental fatigue being significantly higher. A two-way anova with SAH type and external CSF drainage as independent variables and mental fatigue as dependent variable showed a significant main effect of CSF drainage only (P < 0.001). Only mental fatigue explained a significant part of the variance in long-term functional outcome (model χ2 = 52.99, P < 0.001; Nagelkerke R² = 0.32). CONCLUSIONS: Mental fatigue after SAH is a serious burden to the patient and is associated with impaired long-term functional outcome. Distinguishing different aspects of fatigue is relevant as mental post-SAH fatigue might be a target for treatment aimed to improve long-term outcome.

Fatigue does not conjointly alter postural and cognitive performance when standing in a shooting position under dual-task conditions.

This study investigated the effects of fatigue on balance control and cognitive performance in a standing shooting position. Nineteen soldiers were asked to stand while holding a rifle (single task - ST). They also had to perform this postural task while simultaneously completing a cognitive task (dual task - DT). Both the ST and DT were performed in pre- and post-fatigue conditions. In pre-fatigue, participants achieved better balance control in the DT than in the ST, thus suggesting that the increased cognitive activity associated with the DT improves balance control by shifting the attentional focus away from a highly automatised activity. In post-fatigue, balance control was degraded in both the ST and DT, while reaction time was enhanced in the first minutes following the fatiguing exercise without affecting the accuracy of response in the cognitive task, which highlights the relative independent effects of fatigue on balance control and cognitive performance.