Sensation Of Fatigue Research Articles

The Effect of Automotive Seat Cushion Stiffness Distribution on the Subjective Comfort

When body pressures are concentrated, sense of fatigue is increased. To confirm this, correlation analysis between the difference in stiffness of seat and comfort using multiple linear regression analysis has been conducted. For the selected three types of seats which are small-, mid-, and large-size seats, respectively, static tests were con-ducted to measure the distribution of the subject's body pressure on the cushion, through which local stiffness distribution were derived. Also, a subjective comfort evaluation was conducted, and analyzed. According to the present analysis results, the correlation coefficients between stiff-ness of hip area and comfort of hip area were observed to be 0.713 and 0.789, respectively, indicating a strong positive correlation. Thus, the comfort of seat perceived by the driver could be seen to have the largest linear correlation with the stiffness of hip area. Selection of variables for the multiple linear regression analysis was implemented by a backward removal method. Differences of stiffness by areas were selected as independent variables, and subjective comfort evaluation results were selected as dependent variables. According to multiple regression analysis, the comfort of the cushion increased when the left and right balance of the stiffness distribution was maintained even if the body pressure distribution of the hip area was concentrated on one side. According to the analysis results, the stiffness of hip area could be seen to have the greatest linear relationship with the overall satisfaction of comfort, in which comfort is planned to be confirmed by actual production of seats

Prevalence of clinical manifestations of temporomandibular osteoarthrosis

Introduction. The two compartments, disco-temporal and condilo-discal, which make up the temporo-mandibular joint, fulfill the functions of the stomatognathic system, namely: phonation, mastication and swallowing. The temporo-mandibular degenerative pathology is one of the 5 clinical entities given by the American Academy of Orofacial Pain in 1993. The symptoms are varied, dominated by pain, impaired joint mobility, cracks, sensation of muscle fatigue in the masseter and temporal muscles. Most cases benefit from conservative treatment, consisting of anti-allergic and anti-inflammatory medication, specific orthodontic treatment, electrotherapy (TENS, ultrasound, magnetodiaflux, laser), kinesiotherapy. 2-5% of patients require surgery. Material and method. We performed a retrospective study, over a 9-year period (January 2010-March 2019), in which we included 503 patients who went to the Timisoara Oro-Maxillofacial Surgery Clinic, with a definite diagnosis of temporomandibular algodisfunctional syndrome, of different etiologies, between the ages of 6 and 85 years. We evaluated the etiology of temporomandibular algodisfunctional syndrome, the prevalence of clinical manifestations in temporomandibular osteoarthritis and their evolution after 10 days of conservative treatment. Results and discussions. Pain is present in 100% of cases, the values obtained in these patients with temporomandibular osteoarthritis are between 10 and 40mm. Cracks are present in women in the percentage of 40.8% and 37.9% in men; mobility limitation is found in women in 11% of cases, and in men in 15% of cases. Conclusions. The existence of a protocol for the diagnosis of TM osteoarthritis is essential to establish the treatment plan and prognosis of the disease. The pain from osteoarthritis TM is low intensity, present in all patients; cracks and limiting mobility are present in comparable proportions, regardless of gender. The response to treatment was optimal at 21 days of treatment.

Sex differences in perceptual responses to experimental pain before and after an experimental fatiguing arm task

BackgroundThe incidence and prevalence of musculoskeletal disorders (MSDs) is about twice as high in women compared to men, and those of the neck/shoulder region are particularly high among women. Fatigue and responses towards pain are known risk factor for MSDs. However, women have been shown to be less fatigable than men, but more sensitive to experimental pain. From a general standpoint, sex differences in the relationships between the fatigue and pain pathways are poorly understood. This may be due to differences in how men and women conceptually define the sensations of fatigue and pain. The objective of this study was to compare physical and verbal descriptors of fatigue and pain between men and women undergoing an experimental protocol where fatigue and pain were manipulated.MethodsHealthy adult volunteers (14 men and 14 women) underwent experimental pain tests to identify pressure pain threshold (PPT) at biceps brachii (BIC), anterior deltoid (AD), and upper trapezius (UT) followed by the Short-form McGill Pain Questionnaire (SF-MPQ) and Pain Catastrophizing Scale (PCS) before and after a repetitive arm task performed at shoulder height until reaching a rating of neck/shoulder perceived exertion, using the Borg Category Ratio 10 (CR10), greater than 8/10. PPT and MPQ data were analyzed using repeated measures analyses of variance (ANOVA) (time × sex). Correlational analyses were used to investigate relationships between pain measures with time and fatigue.ResultsUT PPT was reduced following the fatiguing task (p ≤ 0.01). Men overall reported higher AD PPT levels compared to women (p ≤ 0.05). MPQ and PCS magnification scores were significantly higher after the fatiguing task (p ≤ 0.05), with no sex differences. Time to fatigue correlated with changes in AD PPT in men and with PCS scores in women.ConclusionsFindings suggest that mechanisms underlying the sensation of acute pain following a repetitive shoulder height task are closely linked with PPT changes in shoulder stabilizers (UT) irrespective of sex, and more so with physical pain responses in men and in attitudes towards pain in women. Sex differences in pain perception may contribute to a better understanding of sex-specific mechanisms underlying neck/shoulder MSDs.

Neural effects of hand-grip-activity induced fatigue sensation on appetite: a magnetoencephalography study

It has been reported that physical activity not only increases energy expenditure, but also affects appetite. However, little remains known about the effects of physical activity-induced fatigue sensation on appetite. In the present study, classical conditioning related to fatigue sensation was used to dissociate fatigue sensation from physical activity. The participants were 20 healthy male volunteers. After overnight fasting, on day 1, the participants performed hand-grip task trials for 10 min with listening to a sound. The next day, they viewed food images with (target task) and without (control task) listening to the sound identical to that used on day 1, and their neural activity during the tasks were recorded using magnetoencephalography. The subjective levels of appetite and fatigue sensation were assessed using a visual analog scale. The subjective level of fatigue increased and that of appetite for fatty foods showed a tendency toward increase in the target task while the subjective level of fatigue and that of appetite for fatty foods were not altered in the control task. In the target task, the decrease of theta (4–8 Hz) band power in the supplementary motor area (SMA), which was observed in the control task, was suppressed, and the suppression was positively correlated with appetite for fatty foods, suggesting hand grip activity-induced fatigue sensation may increase the appetite for fatty food; this increase could be related to neural activity in the SMA. These findings are expected to contribute to the understanding of the neural mechanisms of appetite in relation to fatigue.

The Influence of Tropical Climate on Cognitive Task Performance and Aiming Accuracy in Young International Fencers

This study examined how a tropical climate (TC) influences the cognitive and aiming task performances of young international fencers. The participants performed the tasks in TC and an air-conditioned room. In each session, they completed questionnaires evaluating affective states, fatigue, and comfort and thermal sensations. They also carried out cognitive tasks (simple and choice reaction time, attention, and vigilance tasks) and a motor task testing aiming accuracy with a sword while wearing protective clothing and a mask. TC, which was observed to decrease thermal discomfort, was revealed to decrease aiming accuracy and positive affective states. There was no deleterious effect on cognitive task performance, nor on negative affective states, or fatigue and increased thermal discomfort. These results showed that TC can negatively influence motor performance.

Dry eye syndrome of deficient lacrima production treated with the acupoint thread-embedding therapy: a randomized controlled trial

To compare the therapeutic effects on the relevant symtoms in the patients with dry eye syndrome treated with the acupoint thread-embedding therapy versus topical artificial tears eye drops. A total of 88 patients with dry eye syndrome of deficiency lacrima production were randomized into an acupoint thread-embedding therapy group (thread-embedding group) and a control group with topical artificial tears eye drops (medication group), 44 cases in each one. In the thread-embedding group, 3 cases were dropped out. In the thread-embedding group, Ganshu (BL 18), Pishu (BL 20) and Shenshu (BL 23) etc. were selected and the acupoint thread-embedding therapy was operated once every 30 days, totally for two treatments. In the medication group, the topical artificial tears eye drops was used, 4 to 6 times a day, one drop each time, for 8 weeks totally. Separately, before treatment, after 4-week treatment and 8-week treatment as well as in 8 weeks and 12 weeks of the follow-up, the levels of lactoferrin in tears were determined and the scores of the relevant symptoms of ocular surface such as eye dryness, foreign body sensation in the eyes and eye fatigue were evaluated. In the thread-embedding group, after 4-week and 8-week of treatment as well as in 8-week and 12-week follow-up, the scores of eye dryness, foreign body sensation, burning sensation of eye, phengophobia and eye fatigue were reduced significantly as compared with those before treatment (all P<0.05). In the medication group, the relevant symptoms of ocular surface were reduced after 4-week and 8-week treatment as compared with those before treatment (all P<0.05). In the follow-up, the scores of the relevant symptoms of ocular surface in the thread-embedding group were significantly lower than the medication group (all P<0.05). Separately, after 4-week treatment and 8-week treatment as well as in 8 weeks and 12 weeks of the follow-up, the levels of lactoferrin in tears in the thread-embedding group were significantly increased as compared with those before treatment (all P<0.05). The change was not obvious as compared with that before treatment in the medication group (P>0.05). The levels of lactoferrin in tears at each time point after treatment in the thread-embedding group were higher than the medication group (P<0.05). The acupoint thread-embedding therapy effectively improves in the relevant symptoms of ocular surface, such as eye dryness, foreign body sensation, burning sensation of eye, phengophobia and eye fatigue, and increases the level of lactoferrin in tears in the patients with dry eye syndrome of deficiency aqueous production. In the follow-up, the therapeutic effects of the acupoint thread-embedding therapy are significantly better than artificial tears eye drops.

Are caffeine’s performance-enhancing effects partially driven by its bitter taste?

Caffeine is a well-established ergogenic aid, with its performance-enhancing effects replicated across a variety of exercise types. Caffeine exerts its performance-benefits through many mechanisms, including acting as an adenosine receptor antagonist, and serving to reduce sensations of fatigue and pain. One potential mechanism that is currently underexplored is whether caffeine’s bitter taste mediates some of its ergogenic effects, which is discussed in this article. Previous research has demonstrated that bitter tastants have the ability to enhance performance, and this effect is mediated by bitter taste receptors in the mouth and gastrointestinal tract. Additionally, the ability to detect bitter tastes is subject to individual variation, raising the potential that the demonstrated inter-individual response to a standardised caffeine dose is potentially driven by differences in taste response. Finally, it appears that some of caffeine’s performance-enhancing effects are driven by expectancy. As bitter taste may serve as a signal that caffeine has been ingested, it is possible that some of the expectancy effects of caffeine ingestion are driven by its bitter taste. These aspects all have potentially important implications for future research, as well as for how athletes and coaches utilise caffeine around competition, both of which are explored in depth here.

Health Equity in Rwanda and Boston and Back Again.

I recently cared for an 8-day-old infant in the primary care clinic at 1 of Boston’s safety net hospitals. The exhaustion in his mother’s eyes exceeded the normal fatigue of new motherhood. We communicated with her Haitian Creole and my French, which, even in its mediocrity, brought a look of relief to her face. She was preoccupied with the safety of her 2 older children in Haiti and had fled domestic violence while pregnant. She had delivered her infant without family support and was now sleeping on a friend’s couch with her newborn. She also shared the universal concerns of every new mother: struggles with breastfeeding, mind-numbing fatigue, and fears that every sniffle meant something was wrong with her perfect infant. To arrive at her infant’s appointment, this mother had spent 3 hours transferring between 3 buses, alone with her newborn and without English skills. The infant was healthy and growing but he did not have a safe bed to sleep in. Our social workers and patient navigators quickly located a Pack ’n Play to donate. At the end of our visit, the mother teared up. She had exhausted her cash traveling to the hospital, but even with bus fare, she could not physically carry the infant and the crib home. New to the US hospital setting then, I inquired among my colleagues about options for providing transportation. I was met with sympathy mixed with a sense of fatigue and helplessness because our clinic sees so many similar families. … Address correspondence to Sara N. Stulac, MD, MPH, Department of Pediatrics, Boston Medical Center, 850 Harrison Ave, Boston, MA 02118. E-mail: sara.stulac{at}bmc.org

Decreased alpha-band oscillatory brain activity prior to movement initiated by perception of fatigue sensation

Fatigue is a health problem prevalent in modern societies. Fatigue sensation plays an important role as a biological alarm urging rest to maintain homeostasis, and clarifying the neural mechanisms related to fatigue sensations by which we decide to engage in rest is therefore essential. This study enrolled healthy male volunteers and showed that the decrease in alpha-band power as assessed by magnetoencephalography of the left Brodmann’s area (BA) 6 before perception of fatigue when a button-press based on the level of fatigue was required was smaller than that before perception of the intention to move when a voluntary button-press was required. In addition, the decrease of alpha-band power in the left BA 6 before the perception of fatigue was not altered compared with that in the right BA 6 when a button-press based on the level of fatigue was required. These results suggest that the button-press based on the perception of fatigue is not prepared before the perception of fatigue. These findings will advance the understanding of the neural mechanisms related to subjective feelings such as fatigue sensation.

Physical Exhaustion Induced Variations in Event-Related Potentials and Cognitive Task Performance in Young Adults

Background/Aims: Physical exhaustion is not always peripheral, and it is the brain that causes the sensation of fatigue either due to decrease of metabolic resources or due to central activation process that regulates attention and performance. This study was undertaken to observe the variations in event-related potentials (ERPs) and cognitive performance after an exhausting physical exercise. Methods: A total of 60 healthy young adult subjects were included in the study. The study was conducted in 2 phases with at least a week gap between the phases. The participants answered a Multidimensional Fatigue Inventory (MFI-20) questionnaire before and after trials in each phase to measure the induced physical exhaustion. In phase I (control trial), the ERP data were processed using P300, Standard auditory “oddball paradigm,” on computerized evoked potential recorder (RMS EMG MK-2) using 10/20 system to know the engagement of attention after which participants were given to perform cognitive tasks such as “Stroop Test, Trial Making Test and Mini Mental State Examination.” In Phase II (exercise trial), the participants were instructed to cycle as hard as they could, till they could not continue anymore, which was followed by recording of P300-evoked potentials and performance of cognitive tasks as in Phase I. Paired t test was used to compare between any dependent variables. Results: Fatigue-related subjective measures (MFI-20) showed that both mental and physical exhaustion were significantly greater in the exercise-involved cognitive trial than in the control trial. Lower P300 latencies reflect faster reaction time; however, their response accuracies were poorer resulting in poorer cognitive performances. Participants subjected to control trial performed better in terms of higher percentage accuracy but with slow reaction time. Conclusion: The participants experienced more fatigue physically and mentally during the exercise that involved cognitive tasks. An apparent decrease in attention based on decreased percentage accuracy of response was evident, implying that fatigue, performance, and attention are interdependent.

Stress and Burnout among Nurses Working in Menoufia University Hospitals

More and more employees are experiencing stress on the job nowadays especially those working in the medical field. This stress can be due to work overload, high demands, poor working conditions, long working hours, lack of control, or lack of social support and rewards. There is considerable evidence that stress can lead to various adverse effects on individuals, including somatic disorders, mental health problems, or a sense of tiredness. Burnout among health care employees, mainly medical personnel, has become an occupational hazard with a prevalence in some clinical specialties ranging from 25 to 75 percent. Burnout syndrome (BOS) was characterized as the experience of long-term fatigue and diminished interest, typically in the sense of the work. Therefore, burnout is regarded as the clinical manifestation of occupational stress. Burnout can have significant impacts on people such as job loss, family relationships, psychological disorders, and addictive behavior. In terms of organizational outcome; job burnout causes absenteeism, inefficiency in innovation, and productivity loss. We expect that nurses are especially exposed to high levels of stress during their work, so we conducted the current work aimed at studying stress and burnout among nurses working in hospitals at Menoufia University.

Vocal fatigue in dysphonic teachers who seek treatment.

to verify the self-perception of vocal fatigue of dysphonic teachers in school year activity who sought speech-language pathology assistance. Sixty teachers with voice complaints participated in the study, 30 of whom sought treatment in the Programa de Saúde Vocal do Sindicato dos Professores de São Paulo (SinproSP), and 30 volunteers' teachers who did not seek treatment (G2). All the participants answered a personal identification protocol and work characterization, vocal self-assessment, vocal signs and symptoms checklist, Vocal Fatigue Index protocol (VFI). In addition, a number counting from 1 to 10 and sustained vowel "e" were registered for the definition of the mean vocal deviation using perceptual-auditory judgment. Teachers who sought treatment (G1) obtained worst scores in the VFI, more numbers of signs and symptoms, and worst self-evaluation of the voice when compared with those who did not seek treatment (G2). In addition, teachers in both groups had light to moderate vocal deviation. Dysphonic teachers who sought vocal treatment presented greater sensation of vocal fatigue, especially in the factors of tiredness of voice and voice avoidance and related to physical discomfort associated with voicing of the VFI. In addition, they reported greater number of symptoms and worse vocal self-assessment in relation to those who did not seek treatment, although both groups present deviated voices.

Improvement of the cardiopulmonary capacity of patients with chronic obstructive pulmonary disease of Kinshasa by training of aerobic endurance and resistance

The objective is to determine the effect of aerobic endurance training and resistance on cardiorespiratory fitness in patients with Chronic Obstructive Pulmonary Disease in Kinshasa, Democratic Republic of Congo. In a follow-up study with a duration of 36 weeks, between March and May 2018, 30 mismatched patients with a mean age of 49 ± 9.7 years followed after medical management at the Kinesiology Department's medical fitness laboratory and functional exercises of University Clinics of Kinshasa, were subject to an aerobic endurance and resistance training program of 3 days per week, for one hour 30 minutes per day, three sets of 20 minutes of work and 10 minutes of rest, of moderate intensity including: treadmill walking, ergo-cycle exercises with progressive loading and respiratory gymnastics. The paired Student T test was used to compare the continuous variables before and after the program. A significant decrease in most of the parameters studied respectively: (- 23 bpm) p &amp;lt;0.0001 for resting heart rate; (- 26 bpm); p &amp;lt;0.0001 for heart rate immediately after exercise (-10 mm Hg); p &amp;lt;0.0001 for systolic blood pressure; (- 8 cycles per minute); p &amp;lt;0.0001 for the respiratory rate; (- 20.7%); p &amp;lt;0.0001 for workload (intensity of effort) and (- 10 minutes); p &amp;lt;0.0001 for dyspnea on exertion. On the other hand, a significant increase of: (+ 2.6 liter per second); p &amp;lt;0.0001 for Peak Expiratory Flow; (+ 19%); p &amp;lt;0.0001 for the Tiffeneau index; (+ 51minutes); p &amp;lt;0.0001 for the duration of sensation of fatigue during exercise; (+ 6%), p &amp;lt;0.0001 for oxygen saturation in the open air and (+ 640 meters); p &amp;lt;0.0001 for the walking area. A training program for aerobic endurance and resistance significantly improves the stress tolerance of patients with Chronic Obstructive Pulmonary Disease and can be considered as an effective non-pharmacological management for the improvement of physical capacity as well as the quality of life of these patients.

Force decline after low and high intensity contractions in persons with multiple sclerosis

ObjectiveForce decline during strong contractions is dominated by changes in the periphery whereas during weaker contraction changes in voluntary activation become more important. We compared force decline and contributing factors in persons with multiple sclerosis (PwMS) during low and high intensity contractions. MethodsIndex finger abduction force, force evoked by electrical stimulation of the ulnar nerve at rest (RTw), and during MVCs were investigated in 19 PwMS and 19 controls. Participants performed contractions in sets of six contractions (7 s-on, 3 s-off) at 25% or 80% MVC. After each set, a 5 s-MVC was performed with superimposed nerve stimulation followed by RTw. Contractions were repeated until MVC dropped below 80% of initial MVC. ResultsLow compared to high intensity contractions caused a greater decline in voluntary activation and a smaller decline in RTw. Compared to controls, PwMS accomplished equal sets of contractions but showed a smaller decline in RTw. Female PwMS showed poorer voluntary activation. The number of low intensity contractions was associated with sense of fatigue in PwMS. ConclusionAlthough, no difference in fatigability was observed, the mechanism contributing to force decline differed between PwMS and controls during submaximal contractions. SignificanceDuring weak contractions, fatigue and fatigability are associated in PwMS.

INTER SEASON PHYSIOLOGICAL CONTROL OF THE BRAZILIAN BEACH HANDBALL TEAM

ABSTRACT Introduction: The Brazilian national women's beach handball team traditionally holds intense pre-competition training with several daily sessions in the weeks before major matches. This can cause excessive physical strain, but physiological monitoring can guide the coaching staff to modulate the training load, preventing this excessive strain. Objective: To monitor the physiological responses of members of the Brazilian national women's beach handball team in a pre-competition training program with loads modulated according to individual physiological response. Methods: Seventeen athletes (27.1 ± 3.8 years) were assessed before the start of the pre-competition training period (E1), on Day 8 (E2) and Day 18 (E3). Blood samples were taken for subsequent analysis of muscular damage markers (creatine kinase (CK) and lactate dehydrogenase (LDH)). An ECG test was performed to assess cardiac autonomic modulation (CAM), and the Profile of Mood States (POMS) questionnaire was applied to assess mood. The results were reported to the coaching staff, who made training adjustments according to the individual status of each athlete. Results: CK increased significantly from E1 to E2 (131.1 ± 80.9 vs 212.9 ± 131.7) and remained unchanged (212.9 ± 185.6) up to E3, while LDH was significantly reduced from E2 to E3 (590.7 ± 120.2 vs 457.8 ± 86.6), finishing the pre-competition training program with values similar to E1 (512.7 ± 190.6). The only change noted was the subjective sensation of fatigue from the POMS questionnaire that was significantly higher in E2 (4.82 ± 4.05) and E3 (5.5 ± 4.8) compared to E1 (2.06 ± 2.61), but no changes in total mood disturbance were detected in this instrument. Conclusion: With the modulation of training loads based on results of physiological tests, the members of the Brazilian national women's beach handball team responded in a physiologically adequate manner, even when faced with a sudden increase in training load for 18 consecutive days. Level of evidence III; Diagnostic study-investigation of a diagnostic test.

Acute effects of photobiomodulation therapy (PBMT) combining laser diodes, light-emitting diodes, and magnetic field in exercise capacity assessed by 6MST in patients with COPD: a crossover, randomized, and triple-blinded clinical trial.

Chronic obstructive pulmonary disease (COPD) is characterized by dyspnea, as well as musculoskeletal and systemic manifestations. Photobiomodulation therapy (PBMT) with use of low-level laser therapy (LLLT) and/or light-emitting diode therapy (LEDT) is an electrophysical intervention that has been found to minimize or delay muscle fatigue. The aim of this study was to evaluate the acute effect of PBMT with combined use of lasers diodes, light-emitting diodes (LEDs), magnetic field on muscle performance, exercise tolerance, and metabolic variables during the 6-minute stepper test (6MST) in patients with COPD. Twenty-one patients with COPD (FEV1 46.3% predicted) completed the 6MST protocol over 2weeks, with one session per week. PBMT/magnetic field or placebo (PL) was performed before each 6MST (17 sites on each lower limb, with a dose of 30J per site, using a cluster of 12 diodes 4 × 905nm super-pulsed laser diodes, 4 × 875nm infrared LEDs, and 4 × 640nm red LEDs; Multi Radiance Medical™, Solon, OH, USA). Patients were randomized into two groups before the test according to the treatment they would receive. Assessments were performed before the start of each protocol. The primary outcomes were oxygen uptake and number of steps, and the secondary outcome was perceived exertion (dyspnea and fatigue in the lower limbs). PBMT/magnetic field applied before 6MST significantly increased the number of steps during the cardiopulmonary exercise test when compared to the results with placebo (129.8 ± 10.6 vs 116.1 ± 11.5, p = 0.000). PBMT/magnetic field treatment also led to a lower score for the perception of breathlessness (3.0 [1.0-7.0] vs 4.0 [2.0-8.0], p = 0.000) and lower limb fatigue (2.0 [0.0-5.0] vs 4.0 [0.0-7.0], p = 0.001) compared to that with placebo treatment. This study showed that the combined application of PBMT and magnetic field increased the number of steps during the 6MST and decreased the sensation of dyspnea and lower limb fatigue in patients with COPD.

Prueba de caminata de carga progresiva (Incremental Shuttle Walking Test) en niños sanos

Background: The “incremental shuttle walking test” (ISWT) is an incremental test that allows the functional evaluation of respiratory diseases. It shows a greater correlation between distance walked and the maximum O2 uptake compared to the six-minute walking test. Presently we do not have reference values in Chilean pediatric population. Objective: To know the distance walked by children in the test. Material and Method: This was a correlational descriptive study. The final sample consisted of 60 subjects (35 boys and 25 girls) randomly selected from an age range from 10 to 14 years-old. During the test, walked distance (WD) in meters, basal and final heart rate (HR), dyspnea, subjective sensation of fatigue (SSF), gender, weight (kg), height (m) and cardiac response to exercise (CRE) were recorded. Descriptive statistics were performed in both series followed by a t-test to look for differences among genders. Pearson's correlation coefficient was used to verify the correlation between variables. Results were expressed as mean ± SD. Results: Mean of WD in all the 60 children together was 596.2 ± 178.7 m; in average WD in girls series was 531.6 ± 136.5 m and in boys series was 642.3 ± 192.4 m (p = 0.017). The average height for boys was 1.50 ± 0.08 m and for girls was 1.53 ± 0.08 m (p = 0.245). The average BMI for boys was 18.3 ± 1.6 kg/m2 and for girls was 19.3 ± 2.2 kg/m2 (p = 0.041). Pearson's correlation coefficient between the average of meters walked for all the 60 children together and CRE was 0.570 (p < 0.001). Conclusions: Boys showed a greater WD than girls in ISWT. There was no influence of age, weight, height or BMI on distance walked on the ISWT A positive correlation is shown between the WD and the CRE.

Effects of submaximal cycling at different exercise intensities on maximal isometric force output of the non-exercised elbow flexor muscles.

The purpose of this study was to examine the effects of submaximal cycling at different exercise intensities on maximal isometric force output of the non-exercised elbow flexor muscles after the cycling. A total of 8 healthy young men performed multiple maximal voluntary contractions by the right elbow flexion before, immediately after, 5min after, and 10min after a 6-min submaximal cycling at ventilatory threshold (LI), 70% [Formula: see text] (MI), and 80% [Formula: see text] (HI) with both arms relaxed in the air. Force and surface electromyogram (EMG) of the right biceps brachii muscle during the multiple MVCs, blood lactate concentration ([La]), cardiorespiratory responses, and sensations of fatigue for legs (SEF-L) were measured before, immediately after, 5min after, and 10min after the submaximal cycling with the three different exercise intensities. Immediately after the submaximal cycling, [La], cardiorespiratory responses, and SEF-L were enhanced in proportion to an increase in exercise intensity of the cycling. Changes in force and EMG activity during the multiple MVCs were not significantly different across the three conditions. The findings imply that group III/IV muscle afferent feedback after the submaximal cycling does not determine the magnitude of MVC force loss of the non-exercised upper limb muscles.

Impact of UGT1A1 polymorphisms on Raltegravir and its glucuronide plasma concentrations in a cohort of HIV-1 infected patients

The aim of this study was to evaluate the effect of UGT1A1 polymorphisms on Raltegravir (RAL) and its metabolite RAL-glucuronide trough plasma concentrations ([RAL]plasma and [RAL-glu]plasma) and on the metabolic ratio (MR): [RAL-glu]plasma/[RAL]plasma. UGT1A1 genotyping was performed on 96 patients. 44% (n = 42) were homozygous UGT1A1*1/*1 while 50% (n = 48) and 6% (n = 6) were UGT1A1*28 and UGT1A1*36 carriers, respectively. The median concentration and interquartile range (IQR) of [RAL]plasma were 88.5 ng/ml (41.0–236), 168 ng/ml (85.8–318) and 92.5 ng/ml (36.4–316) for UGT1A1*1/*1, UGT1A1*28 and UGT1A1*36 carriers, respectively. Only the difference between UGT1A1*1/*1 and *28 carriers was statistically significant (p = 0.022). The median MR (IQR) were 5.8 (3–10), 2.9 (1.6–5.3) and 3.2 (1.7–5.9) for UGT1A1*1/*1, UGT1A1*28 and UGT1A1*36 carriers, respectively. Only the difference between UGT1A1*1/*1 and *28 carriers was statistically significant (p = 0.004) with an allele-dependent effect: UGT1A1*28 homozygous having lower MR than heterozygous carriers who show lower MR compared to *1/*1. Except for the sensation of fatigue, this PK effect did not correlate with clinical adverse events or biological abnormalities. In Conclusion, we demonstrate that UGT1A1*28 polymorphism has a significant impact on RAL metabolism: UGT1A1*28 carriers being characterized by higher [RAL]plasma and lower MR.

The neural effects of positively and negatively re-experiencing mental fatigue sensation: a magnetoencephalography study.

Fatigue sensation is an essential biological alarm that urges us to take rest to avoid disrupting homeostasis and thus plays an important role in maintaining well-being. However, there are situations in which the anticipation of unpleasant fatigue sensation undesirably reduces motivation for activity. The aim of this study was to examine whether thinking positively about the fatigue sensation would increase motivation to accomplish the workload. Fourteen healthy male volunteers participated in this study and performed a two-back test for 30min to induce mental fatigue sensation. After their subjective level of fatigue had recovered to the baseline level, they re-experienced the fatigue sensation experienced in the two-back test positively, negatively, and without any modification (i.e., re-experienced the fatigue sensation as it was). The level of motivation to perform another two-back test they felt during the re-experiencing was assessed. The neural activity related to the re-experiencing was recorded using magnetoencephalography. The level of the motivation to perform another two-back test was increased by positively re-experiencing the fatigue sensation. The increase in delta band power in Brodmann area 7 was positively associated with the increase in motivation. These results show that positive thinking about fatigue sensation can enhance motivation and suggest that this enhanced motivation may have some effects on visual attention system.