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Awards can propel academic careers. They also reflect the culture and values of the scientific community. But do awards incentivize greater transparency, inclusivity, and openness in science? Our cross-disciplinary survey of 222 awards for the "best" journal articles across all 27 SCImago subject areas revealed that journals and learned societies administering such awards generally publish little detail on their procedures and criteria. Award descriptions were brief, rarely including contact details or information on the nominations pool. Nominations of underrepresented groups were not explicitly encouraged, and concepts that align with Open Science were almost absent from the assessment criteria. At the same time, 10% of awards, especially the recently established ones, tended to use article-level impact metrics. USA-affiliated researchers dominated the winner's pool (48%), while researchers from the Global South were uncommon (11%). Sixty-one percent of individual winners were men. Overall, Best Paper awards miss the global calls for greater transparency and equitable access to academic recognition. We provide concrete and implementable recommendations for scientific awards to improve the scientific recognition system and incentives for better scientific practice., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Lagisz et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Purpose: With few treatment options available for non-ambulatory children with cerebral palsy (CP), a robotic lower extremity gait trainer may provide a non-invasive addition to conventional treatment options. This case study investigates the usage and impact of robotic lower extremity gait trainer use in a participant with CP over the initial 3 months of use., Materials and Methods: This prospective case study involves a 7-year old female (GMFCS V) with CP (registered clinical trial: NCT04251390). The participant used a Trexo Home robotic gait trainer (Trexo) in the community with assessments occurring in the home and school. Trexo usage and bowel movements (BMs) were tracked daily. Postural control and lower extremity range of motion (ROM) and spasticity were evaluated prior to Trexo use and weekly to biweekly thereafter., Results: The participant used the device an average of 46 min/week, over 3.3 d/week. BM frequency increased from 0.4/d at baseline, to 1.2 (±0.5)/d during Trexo use. There were no diffuse systematic changes in postural stability, ROM or muscle spasticity, but specifically head control and spasticity in the knee flexors had improvements., Conclusions: Data and anecdotal reports suggest that regular use of the Trexo Home robotic gait trainer has positive outcomes on frequency and quality of BMs, and may improve head control, and knee flexor spasticity. Larger controlled studies are needed to evaluate the impacts of Trexo use in children with CP.Implications for RehabilitationNon-ambulatory children with CP can use and may experience benefits from using a robot-assisted gait trainer (RAGT).Constipation, aspects of balance and focal spasticity may improve.

Repeated spaced TMS protocols, also termed accelerated TMS protocols, are of increasing therapeutic interest. The long-term potentiation (LTP)-like effects of repeated spaced intermittent theta-burst transcranial magnetic stimulation (iTBS) are presumed to be N-Methyl-D-Aspartate receptor (NMDA-R) dependent; however, this has not been tested. We tested whether the LTP-like effects of repeated spaced iTBS are influenced by low-dose D-Cycloserine (100 mg), an NMDA-R partial-agonist. We conducted a randomized, double-blind, placebo-controlled crossover trial in 20 healthy adults from August 2021-Feb 2022. Participants received repeated spaced iTBS, consisting of two iTBS sessions 60 minutes apart, to the primary motor cortex. The peak-to-peak amplitude of the motor evoked potentials (MEP) at 120% resting motor threshold (RMT) was measured after each iTBS. The TMS stimulus-response (TMS-SR; 100-150% RMT) was measured at baseline, +30 min, and +60 min after each iTBS. We found evidence for a significant Drug*iTBS effect in MEP amplitude, revealing that D-Cycloserine enhanced MEP amplitudes relative to the placebo. When examining TMS-SR, pairing iTBS with D-Cycloserine increased the TMS-SR slope relative to placebo after both iTBS tetani, and this was due to an increase in the upper bound of the TMS-SR. This indicates that LTP-like and metaplastic effects of repeated-spaced iTBS involve NMDA-R, as revealed by two measures of corticospinal excitability, and that low-dose D-Cycloserine facilitates the physiological effects of repeated spaced iTBS. However, extension of these findings to clinical populations and therapeutic protocols targeting non-motor regions of cortex requires empirical validation., (© 2023. The Author(s), under exclusive licence to American College of Neuropsychopharmacology.)

Transcranial magnetic stimulation (TMS) motor mapping is a safe, non-invasive method used to study corticomotor organization and intervention-induced plasticity. Reliability of resting maps is well established, but understudied for active maps and unestablished for active maps obtained using robotic TMS techniques. The objective of  this study was to determine the reliability of robotic neuro-navigated TMS motor map measures during active muscle contraction. We hypothesized that map area and volume would show excellent short- and medium-term reliability. Twenty healthy adults were tested on 3 days. Active maps of the first dorsal interosseous muscle were created using a 12 × 12 grid (7 mm spacing). Short- (24 h) and medium-term (3-5 weeks) relative (intra-class correlation coefficient) and absolute (minimal detectable change (MDC); standard error of measure) reliabilities were evaluated for map area, volume, center of gravity (CoG), and hotspot magnitude (peak-to-peak MEP amplitude at the hotspot), along with active motor threshold (AMT) and maximum voluntary contraction (MVC). This study found that AMT and MVC had good-to-excellent short- and medium-term reliability. Map CoG (x and y) were the most reliable map measures across sessions with excellent short- and medium-term reliability (p < 0.001). Map area, hotspot magnitude, and map volume followed with better reliability medium-term than short-term, with a change of 28%, 62%, and 78% needed to detect a true medium-term change, respectively. Therefore, robot-guided neuro-navigated TMS active mapping is relatively reliable but varies across measures. This, and MDC, should be considered in interventional study designs., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: Long COVID, an illness affecting a subset of individuals after COVID-19, is distressing, poorly understood, and reduces quality of life. The objective of this sub-study was to better understand and explore individuals' experiences with long COVID and commonly reported symptoms, using qualitative data collected from open-ended survey responses., Methods: Data were collected from adults living with long COVID who participated in a larger observational online survey. Participants had the option of answering seven open-ended items. Data from the open-ended items were analyzed following guidelines for reflective thematic analysis., Results: From 213 participants who were included in the online survey, 169 participants who primarily self-identified as women (88.2%), aged 40-49 (33.1%), who had been experiencing long COVID symptoms for ≥ 6 months (74%) provided open-ended responses. Four overlapping and interconnected themes were identified: (1) Long COVID symptoms are numerous and wearing, (2) The effects of long COVID are pervasive, (3) Physical activity is difficult and, in some cases, not possible, and (4) Asking for help when few are listening, and little is working., Conclusion: Findings reaffirm prior research, highlighting the complex nature of long COVID. Further, results show the ways individuals affected by the illness are negatively impacted and have had to alter their daily activities. Participants recounted the challenges faced when advocating for themselves, adapting to new limitations, and navigating healthcare systems. The varied relapsing-remitting symptoms, unknown prognosis, and deep sense of loss over one's prior identity suggest interventions are needed to support this population., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Purpose: Cancer-related fatigue (CRF) is a common and distressing symptom of cancer that may persist for years following treatment completion. However, little is known about the pathophysiology of CRF. Using a comprehensive group of gold-standard physiological and psychosocial assessments, this study aimed to identify correlates of CRF in a heterogenous group of cancer survivors., Methods: Using a cross-sectional design to determine the physiological and psychosocial correlates of CRF, ninety-three cancer survivors (51 fatigued, 42 non-fatigued) completed assessments of performance fatigability (i.e. the decline in muscle strength during cycling), cardiopulmonary exercise testing, venous blood samples for whole blood cell count and inflammatory markers and body composition. Participants also completed questionnaires measuring demographic, treatment-related, and psychosocial variables., Results: Performance fatigability, time-to-task-failure, peak oxygen uptake (V̇O 2peak ), tumor necrosis factor-α (TNF-α), body fat percentage, and lean mass index were associated with CRF severity. Performance fatigability, V̇O 2peak , TNF-α, and age explained 35% of the variance in CRF severity. Those with clinically-relevant CRF reported more pain, more depressive symptoms, less perceived social support, and were less physically active than non-fatigued cancer survivors., Conclusions: The present study utilised a comprehensive group of gold-standard physiological and psychosocial assessments and the results give potential insight into the mechanisms underpinning the association between physical inactivity, physical deconditioning and CRF., Implications for Cancer Survivors: Given the associations between CRF and both physiological and psychosocial measures, this study identifies targets that can be measured by rehabilitation professionals and used to guide tailored interventions to reduce fatigue., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The aim of this study was to examine the relationship between perceived fatigue and perceptions of walking abilities and difficulty in people with cerebral palsy (CP). Twenty individuals with CP (range 10-21y; mean age 14.8y) who usually walk in the community were recruited. Community mobility was assessed using the Functional Mobility Scale. Participants were asked about their walking ability and frequency, perceived effort during walking (using the Children's Effort Rating Table), and perceived fatigue (using the Fatigue Impact and Severity Self-Assessment). Community mobility, frequency, and perceived effort during walking were significantly related to fatigue. No relationship was found between time spent walking (maximum walking time) and fatigue. Here we demonstrate that perceived fatigue is related to walking in people with CP.

Background: Although much is known about cognitive dysfunction in attention-deficit/hyperactivity disorder (ADHD), few studies have examined the pathophysiology of disordered motor circuitry. We explored differences in neurometabolite levels and transcranial magnetic stimulation (TMS)-derived corticomotor representations among children with ADHD and typically developing children., Methods: We used magnetic resonance spectroscopy (MRS) protocols to measure excitatory (glutamate + glutamine [Glx]) and inhibitory (γ-aminobutyric acid [GABA]) neurometabolite levels in the dominant primary motor cortex (M1) and the supplementary motor area (SMA) in children with ADHD and typically developing children. We used robotic neuronavigated TMS to measure corticospinal excitability and create corticomotor maps., Results: We collected data from 26 medication-free children with ADHD (aged 7-16 years) and 25 typically developing children (11-16 years). Children with ADHD had lower M1 Glx ( p = 0.044, d = 0.6); their mean resting motor threshold was lower ( p = 0.029, d = 0.8); their map area was smaller ( p = 0.044, d = 0.7); and their hotspot density was higher ( p = 0.008, d = 0.9). M1 GABA levels were associated with motor map area ( p = 0.036). Limitations: Some TMS data were lost because the threshold of some children exceeded 100% of the machine output. The relatively large MRS voxel required to obtain sufficient signal-to-noise ratio and reliably measure GABA levels encompassed tissue beyond the M1, making this measure less anatomically specific., Conclusion: The neurochemistry and neurophysiology of key nodes in the motor network may be altered in children with ADHD, and the differences appear to be related to each other. These findings suggest potentially novel neuropharmacological and neuromodulatory targets for ADHD., Competing Interests: Competing interests: A. Kirton reports grants or contracts from the Canadian Institutes for Health Research, Alberta Innovates, the Cerebral Palsy Alliance Research Foundation and the Kids Brain Health Network; participation on an advisory board for the PumpKin trial; and membership on the board of the International Pediatric Stroke Organization. No other competing interests were declared., (© 2022 CMA Impact Inc. or its licensors.)

Transcranial magnetic stimulation (TMS) motor mapping is a safe, non-invasive method that can be used to study corticomotor organization. Motor maps are typically acquired at rest, and comparisons to maps obtained during muscle activation have been both limited and contradictory. Understanding the relationship between functional activation of the corticomotor system as recorded by motor mapping is crucial for their use clinically and in research. The present study utilized robotic TMS paired with personalized neuro-navigation to examine the relationship between resting and active motor map measures and their relationship with motor performance. Twenty healthy right-handed participants underwent resting and active robotic TMS motor mapping of the first dorsal interosseous to 10% maximum voluntary contraction. Motor map parameters including map area, volume, and measures of map centrality were compared between techniques using paired sample tests of difference and Bland-Altman plots and analysis. Map area, volume, and hotspot magnitude were larger in the active motor maps, while map center of gravity and hotspot locations remained consistent between both maps. No associations were observed between motor maps and motor performance as measured by the Purdue Pegboard Test. Our findings support previous suggestions that maps scale with muscle contraction. Differences in mapping outcomes suggest rest and active motor maps may reflect functionally different corticomotor representations. Advanced analysis methods may better characterize the underlying neurophysiology of both types of motor mapping., (© 2022 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Fatigue is a common experience in both health and disease. Yet, pathological (i.e., prolonged or chronic) and transient (i.e., exertional) fatigue symptoms are traditionally considered distinct, compounding a separation between interested research fields within the study of fatigue. Within the clinical neurosciences, nascent frameworks position pathological fatigue as a product of inference derived through hierarchical predictive processing. The metacognitive theory of dyshomeostasis (Stephan et al., 2016) states that pathological fatigue emerges from the metacognitive mechanism in which the detection of persistent mismatches between prior interoceptive predictions and ascending sensory evidence (i.e., prediction error) signals low evidence for internal generative models, which undermine an agent's feeling of mastery over the body and is thus experienced phenomenologically as fatigue. Although acute, transient subjective symptoms of exertional fatigue have also been associated with increasing interoceptive prediction error, the dynamic computations that underlie its development have not been clearly defined. Here, drawing on the metacognitive theory of dyshomeostasis, we extend this account to offer an explicit description of the development of fatigue during extended periods of (physical) exertion. Accordingly, it is proposed that a loss of certainty or confidence in control predictions in response to persistent detection of prediction error features as a common foundation for the conscious experience of both pathological and nonpathological fatigue., (© 2021. The Author(s).)

Objective: People living with long COVID describe a high symptom burden, and a more detailed assessment is needed to inform rehabilitation recommendations. The objectives were to use validated questionnaires to measure the severity of fatigue and compare this with normative data and thresholds for clinical relevance in other diseases; measure and describe the impact of postexertional malaise (PEM); and assess symptoms of dysfunctional breathing, self-reported physical activity, and health-related quality of life., Methods: This was an observational study with a cross-sectional survey design (data collection from February 2021 to April 2021). Eligible participants were adults experiencing persistent symptoms due to COVID-19 that did not predate the confirmed or suspected infection. Questionnaires included the Functional Assessment of Chronic Illness Therapy-Fatigue Scale and the DePaul Symptom Questionnaire-Post-Exertional Malaise., Results: After data cleaning, 213 participants were included in the analysis. The total Functional Assessment of Chronic Illness Therapy-Fatigue Scale score was 18 (SD = 10) (where the score can range from 0 to 52, and a lower score indicates more severe fatigue), and 71.4% were experiencing chronic fatigue. Postexertional symptom exacerbation affected most participants, and 58.7% met the PEM scoring thresholds used in people living with myalgic encephalomyelitis/chronic fatigue syndrome., Conclusion: Long COVID is characterized by chronic fatigue that is clinically relevant and at least as severe as fatigue in several other clinical conditions. PEM is a significant challenge for this patient group. Because of the potential for setbacks and deteriorated function following overexertion, fatigue and postexertional symptom exacerbation must be monitored and reported in clinical practice and in studies involving interventions for people with long COVID., Impact: Physical therapists working with people with long COVID should measure and validate the patient's experience. Postexertional symptom exacerbation must be considered, and rehabilitation needs to be carefully designed based on individual presentation. Beneficial interventions might first ensure symptom stabilization via pacing, a self-management strategy for the activity that helps minimize postexertional malaise., (© The Author(s) 2022. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: The subjective experience of fatigue impairs an individual's ability to sustain physical endurance performance. However, precise understanding of the specific role perceived fatigue plays in the central regulation of performance remains unclear. Here, we examined whether the subjective intensity of a perceived state of fatigue, pre-induced through prior upper body activity, differentially impacted performance and altered perceived effort and affect experienced during a sustained, isometric contraction in lower body. We also explored whether (cardiac) interoception predicted the intensity of experienced perceptual and affective responses and moderated the relationships between constructs during physical activity., Methods: Using a repeated-measures study design, thirty male participants completed three experimental conditions, with the intensity of a pre-induced state of fatigue manipulated to evoke moderate (MOD), severe (SEV) and minimal (control; CON) intensity of perceptions prior to performance of the sustained contraction., Results: Performance of the sustained contraction was significantly impaired under a perceived state of fatigue, with reductions of 10% and 14% observed in the MOD and SEV conditions, respectively. Performance impairment was accompanied by greater perceived effort and more negative affective valence reported during the contraction. However, effects were limited to comparisons to CON, with no difference evident between the two experimental trials (i.e. MOD vs. SEV). Individuals' awareness of their accuracy in judging resting heartbeats was shown to predict the subjective intensity of fatigue experienced during the endurance task. However, interoception did not moderate the relationships evident between fatigue and both perceived effort and affective valence., Conclusions: A perceived state of fatigue limits endurance performance, influencing both how effortful activity is perceived to be and the affective experience of activity. Though awareness of interoceptive representations of bodily states may be important to the subjective experience of fatigue, interoception does not modulate the relationships between perceived fatigue and other perceptual (i.e. effort) and affective constructs., Competing Interests: The authors have declared that no competing interests exist.

Introduction: Conventional transcranial direct current stimulation (tDCS) and high-definition tDCS (HD-tDCS) may improve motor learning in children. Mechanisms are not understood. Neuronavigated robotic transcranial magnetic stimulation (TMS) can produce individualised maps of primary motor cortex (M1) topography. We aimed to determine the effects of tDCS- and HD-tDCS-enhanced motor learning on motor maps. Methods: Typically developing children aged 12-18 years were randomised to right M1 anodal tDCS, HD-tDCS, or Sham during training of their left-hand on the Purdue Pegboard Task (PPT) over 5 days. Bilateral motor mapping was performed at baseline (pre), day 5 (post), and 6-weeks retention time (RT). Primary muscle was the first dorsal interosseous (FDI) with secondary muscles of abductor pollicis brevis (APB) and adductor digiti minimi (ADM). Primary mapping outcomes were volume (mm 2 /mV) and area (mm 2 ). Secondary outcomes were centre of gravity (COG, mm) and hotspot magnitude (mV). Linear mixed-effects modelling was employed to investigate effects of time and stimulation type (tDCS, HD-tDCS, Sham) on motor map characteristics. Results: Twenty-four right-handed participants (median age 15.5 years, 52% female) completed the study with no serious adverse events or dropouts. Quality maps could not be obtained in two participants. No effect of time or group were observed on map area or volume. LFDI COG (mm) differed in the medial-lateral plane (x-axis) between tDCS and Sham (p = 0.038) from pre-to-post mapping sessions. Shifts in map COG were also observed for secondary left-hand muscles. Map metrics did not correlate with behavioural changes. Conclusion: Robotic TMS mapping can safely assess motor cortex neurophysiology in children undergoing motor learning and neuromodulation interventions. Large effects on map area and volume were not observed while changes in COG may occur. Larger controlled studies are required to understand the role of motor maps in interventional neuroplasticity in children., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Giuffre, Zewdie, Wrightson, Cole, Carlson, Kuo, Babwani and Kirton.)

Introduction: Transcranial magnetic stimulation (TMS) motor mapping can characterize the neurophysiology of the motor system. Limitations including human error and the challenges of pediatric populations may be overcome by emerging robotic systems. We aimed to show that neuronavigated robotic motor mapping in adolescents could efficiently produce discrete maps of individual upper extremity muscles, the characteristics of which would correlate with motor behavior., Methods: Typically developing adolescents (TDA) underwent neuronavigated robotic TMS mapping of bilateral motor cortex. Representative maps of first dorsal interosseous (FDI), abductor pollicis brevis (APB), and abductor digiti minimi (ADM) muscles in each hand were created. Map features including area (primary), volume, and center of gravity were analyzed across different excitability regions (R100%, R75%, R50%, R25%). Correlations between map metrics and validated tests of hand motor function (Purdue Pegboard Test as primary) were explored., Results: Twenty-four right-handed participants (range 12-18 years, median 15.5 years, 52% female) completed bilateral mapping and motor assessments with no serious adverse events or dropouts. Gender and age were associated with hand function and motor map characteristics. Full motor maps (R100%) for FDI did not correlate with motor function in either hand. Smaller excitability subset regions demonstrated reduced variance and dose-dependent correlations between primary map variables and motor function in the dominant hemisphere., Conclusions: Hand function in TDA correlates with smaller subset excitability regions of robotic TMS motor map outcomes. Refined motor maps may have less variance and greater potential to quantify interventional neuroplasticity. Robotic TMS mapping is safe and feasible in adolescents., (© 2021 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Robotic transcranial magnetic stimulation (TMS) is a noninvasive and safe tool that produces cortical motor maps using neuronavigational and neuroanatomical images. Motor maps are individualized representations of the primary motor cortex (M1) topography that may reflect developmental and interventional plasticity. Results of TMS motor map reliability testing have been variable, and robotic measures are undefined. We aimed to determine the short- and long-term reliability of robotic TMS motor maps. Twenty healthy participants underwent motor mapping at baseline, 24 h, and 4 wk. A 12 × 12 grid (7-mm spacing) was placed over the left M1, centered over the hand knob area. Four suprathreshold stimulations were delivered at each grid point. First dorsal interosseous (FDI) motor-evoked potentials (MEPs) were analyzed offline to generate map characteristics of area, volume, center of gravity (COG), and hotspot magnitude. Subsets of each outcome corresponding to 75%, 50%, and 25% of each map were determined. Reliability measures including intraclass correlation coefficient (ICC), minimal detectable change (MDC), and standard error of measure (SEM) were calculated. Map volume, COG, and hotspot magnitude were the most reliable measures (good-to-excellent) over both short- and long-term sessions. Map area reliability was poor-to-moderate for short- and long-term sessions. Smaller map percentile subsets showed decreased variability but only minimal improvements in reliability. MDC for most outcomes was >50%. Procedures were well tolerated with no serious adverse events. Robotic TMS motor mapping is relatively reliable over time, but careful consideration of specific outcomes is required for this method to interrogate plasticity in the human motor system. NEW & NOTEWORTHY Robotic transcranial magnetic stimulation (TMS) is a noninvasive and safe tool that produces cortical motor maps-individualized representations of the primary motor cortex (M1) topography-that may reflect developmental and interventional plasticity. This study is the first to evaluate short- and long-term relative and absolute reliability of TMS mapping outcomes at various M1 excitability levels using novel robotic neuronavigated TMS.

Prior exercise has previously been shown to impair subsequent endurance performance in non-activated muscles. Declines in the neuromuscular function and altered perceptual/affective responses offer possible mechanisms through which endurance performance may be limited in these remote muscle groups. We thus conducted two experiments to better understand these performance-limiting mechanisms. In the first experiment, we examined the effect of prior handgrip exercise on the behavioral, perceptual, and affective responses to a sustained, sub-maximal contraction of the knee extensors. In the second experiment, transcranial magnetic stimulation was used to assess the neuromuscular function of the knee extensors before and after the handgrip exercise. The results of the first experiment demonstrated prior handgrip exercise increased the perceptions of effort and reduced affective valence during the subsequent knee extensor endurance exercise. Both effort and affect were associated with endurance performance. Subjective ratings of fatigue were also increased by the preceding handgrip exercise but were not directly related to knee extensor endurance performance. However, perceptions of fatigue were correlated with heightened effort perception and reduced affect during the knee extensor contraction. In the second experiment, prior handgrip exercise did not significantly alter the neuromuscular function of the knee extensors. The findings of the present study indicate that motor performance in the lower limbs following demanding exercise in the upper body appears to be regulated by complex, cognitive-emotional interactions, which may emerge independent of altered neuromuscular function. Subjective fatigue states are implicated in the control of perceptual and affective processes responsible for the regulation of endurance performance., (© 2020 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Context: Cancer-related fatigue (CRF) is a distressing and persistent sense of tiredness or exhaustion that interferes with usual functioning. Chronic CRF continues for months after curative cancer treatment is complete. Post-exertional malaise (PEM) is a worsening of symptoms after physical or mental activity, with limited investigations in people with chronic CRF., Objectives: The purpose of this study was to identify and describe self-reported incidences of PEM in people with chronic CRF., Methods: Participants (n = 18) were eligible if they scored ≤34 on the Functional Assessment of Chronic Illness Therapy-Fatigue scale and had a cancer-related onset of fatigue. Participants completed a brief questionnaire to assess PEM during a six-month time frame (the DePaul Symptom Questionnaire-PEM). In addition, a maximal exercise test was used to investigate self-reported symptom exacerbation (via an open-ended questionnaire) after strenuous physical exertion., Results: On the DePaul Symptom Questionnaire-PEM, three participants met previously defined scoring criteria, which included experiencing moderate to very severe symptoms at least half of the time, worsening of fatigue after minimal effort, plus a recovery duration of >24 hours. Content analysis of responses to open-ended questionnaires identified five people who experienced a delayed recovery and symptoms of PEM after maximal exercise., Conclusion: A subset of people with chronic CRF (up to 33% in this sample) may experience PEM. Exercise specialists and health care professionals working with people with chronic CRF must be aware that PEM may be an issue. Symptom exacerbation after exercise should be monitored, and exercise should be tailored and adapted to limit the potential for harm., (Copyright © 2020 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.)

Anodal transcranial direct current stimulation (tDCS) of the primary motor cortex has been reported to improve isometric exercise performance without changing corticospinal excitability. One possible cause for this may be the previous use of relatively high (2 mA) current intensities, which have inconsistent effects on corticospinal excitability. The present pre-registered study aimed to replicate previously reported ergogenic effects of 2 mA tDCS and examine whether 1 mA anodal tDCS both improved isometric exercise performance and perceived fatigue, and more reliably altered corticospinal excitability. On three separate occasions, participants performed a sustained submaximal isometric knee extension until failure after receiving either 1, 2 mA or sham anodal tDCS. Corticospinal excitability of the knee extensors was measured using transcranial magnetic stimulation immediately before and after tDCS. Rating of fatigue was recorded throughout the isometric exercise. Neither 1 nor 2 mA tDCS improved exercise performance, or reduced perceived fatigue, compared with sham stimulation. There was also no effect of tDCS on the corticospinal excitability of the knee extensors. We found no effect of tDCS on either exercise performance, perceived fatigue or corticospinal excitability. This study adds to the growing body of literature reporting no ergogenic effect of tDCS. Large pre-registered replications of previously reported effects are now required before tDCS can be considered an effective method to improve exercise performance., (© 2019 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Sustained isometric maximal voluntary contractions (IMVCs) have blood flow occlusive effects on the microvasculature. However, it is unknown if this effect would be magnified with additional blood flow restriction via a cuff and what the influence on fatigue development would be. Twelve healthy male participants performed a 1-min IMVC of the knee extensors with and without additional blood flow occlusion induced by pneumatic cuff in counterbalanced order on separate days. Vastus lateralis muscle deoxygenation was estimated via near-infrared spectroscopy-derived tissue oxygen saturation (SmO 2 ) throughout the fatiguing contraction. Central and peripheral measures of neuromuscular fatigue (NMF) were assessed via surface electromyography (EMG) and force responses to voluntary contractions and peripheral nerve/transcranial magnetic stimulations before, immediately after, and throughout an 8-min recovery period. SmO 2 , force, and EMG amplitude decreased during the 1-min IMVC, but there were no between-condition differences. Similarly, no significant ( p > 0.05) between-condition differences were detected for any dependent variable immediately after the fatiguing contraction. Transcranial magnetic stimulation (TMS)-derived voluntary activation was lower ( p < 0.05) in the no-cuff condition during the recovery period. Sustained IMVC results in a similar degree of muscle deoxygenation and NMF as IMVCs with additional occlusion, providing further evidence that a sustained IMVC induces full ischemia. Novelty NMF etiology, muscle oxygenation, and corticospinal factors during an IMVC are similar with or without an occlusion cuff. Contrary to all other measures, TMS-evaluated voluntary activation returned to baseline faster following the occluded condition.

The aim of this study was to investigate differences in neuromuscular function and corticospinal excitability in response to sustained unilateral (UNIL) and bilateral (BIL) isometric maximal voluntary contraction (IMVC) of the knee extensors. Eleven men performed a 1-min sustained IMVC of the knee extensors with one or both legs. Central and peripheral measures of neuromuscular function and corticospinal excitability were assessed via surface electromyography (EMG), peripheral nerve stimulation, and transcranial magnetic stimulation before, immediately after, and during recovery from IMVC. IMVC force and root-mean-squared EMG decreased during the fatiguing 1-min IMVC, with a larger decrease in EMG during BIL. All neuromuscular function indexes decreased significantly after the IMVC ( P < 0.005), but the magnitude of these decreases did not differ between conditions. Changes in corticospinal excitability (motor evoked potential) and inhibition (silent period) did not differ between conditions. In contrast to previous studies utilizing submaximal exercise, no more peripheral fatigue was found after UNIL vs. BIL conditions, even though central drive was lower after BIL 1-min IMVC. Corticospinal excitability and inhibition were not found to be different between UNIL and BIL conditions, in line with maximal voluntary activation. NEW & NOTEWORTHY The present experiment used peripheral nerve stimulation and transcranial magnetic stimulations during a sustained isometric maximal voluntary contraction to investigate the influence of muscle mass on neuromuscular fatigue. Contrary to previous studies that used submaximal exercise, peripheral fatigue was not found to be greater in unilateral vs. bilateral knee extensions even though central drive was lower during bilateral contractions. Corticospinal excitability and inhibition were not found to be different between unilateral and bilateral conditions.

Aim: To characterize fatigue in children with hemiparesis with perinatal stroke and explore associations with measures of motor performance and corticospinal excitability., Method: Forty-five children (16 females, 29 males), aged 6 to 18 years (mean [SD] 12y [4]), with magnetic resonance imaging-confirmed perinatal stroke participated. Associations between fatigue (Pediatric Quality of Life Inventory Version 3.0 cerebral palsy module fatigue subscale), motor performance (Assisting Hand Assessment [AHA], Box and Blocks Test, grip strength), and excitability of corticospinal projections to both hands were examined using ranked tests of correlation, robust regression, and the Mann-Whitney U test., Results: Nearly half of the participants (n=21) reported experiencing fatigue in the previous month. Function in the less affected hand (Box and Blocks Test, grip strength) was correlated with fatigue scores. Participants with preserved ipsilateral projections to the more affected hand had less fatigue, and scores correlated with the excitability of these projections. Fatigue scores were not associated with age, sex, or AHA score., Interpretation: Fatigue is common in children with hemiparesis with perinatal stroke and is associated with motor performance and the presence and excitability of ipsilateral corticospinal projections from the contralesional hemisphere to the more affected hand., What This Paper Adds: Fatigue is common in children with hemiparesis with perinatal stroke. Fatigue was associated with motor performance and strength in the less affected, but not the more affected, hand. Fatigue was associated with the presence and excitability of ipsilateral corticospinal projections from the contralesional hemisphere., (© 2019 Mac Keith Press.)

Background: The dual-task effect on walking performance is different during treadmill and overground walking, though the cause of this difference is unknown. This study examined the effects of task prioritization on overground and treadmill dual-task walking., Method: Twenty-two adults walked overground and on a treadmill under three dual-task conditions: prioritization of walking performance, prioritization of cognitive performance (serial subtraction in sevens), or no prioritization., Results: Compared to single-task walking, stride velocity was reduced and stride time variability was increased during dual-task overground walking. During treadmill walking, there was no dual-task effect on walking performance, but cognitive task performance was improved. Prioritization of the cognitive task reduced the dual-task effect on stride velocity during overground walking only, whilst prioritization of the walking task reduced cognitive task performance in both walking modalities., Significance: These results corroborate recent findings that the dual-task effects on treadmill walking are not equivalent to those on overground walking. Healthy adults appear to prioritize cognitive task performance during treadmill dual-task walking without detrimental effects to gait. During overground walking however, allocation of attention to the secondary task reduces gait performance. These results indicate that treadmill based dual-task paradigms should not be used to infer factors which influence the cognitive control of overground walking., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Purpose: To test the accuracy, validity, reliability and sensitivity of an alternative method for the measure of TMS-assessed voluntary activation (VATMS) in the knee extensors., Methods: Ten healthy males (24 ± 5 years) completed a neuromuscular assessment protocol before and after a fatiguing isometric exercise: two sets of five contractions (50%, 62.5%, 75%, 87.5%, 100% Maximal Voluntary Contraction; MVC) with superimposed TMS-evoked twitches for calculation of VATMS using either the first 5 stimulations (1x5C) or all 10 (2x5C). This was performed on two separate occasions (between-day reliability). Accuracy and validity were compared with a routinely used protocol [i.e. 50%, 75%, and 100% of MVC (1x3C) performed three times (3x3C)]., Results: 95% confidence interval for estimated resting twitch, a key determinant of VATMS, was similar between 1x5C, 2x5C, and 3x3C but improved by six-fold when compared to 1x3C (P<0.05). In a fresh state, potentiated twitch force was unchanged following 1x5C but decreased following 2x5C (P<0.05). A recovery was found post-exercise but was smaller for 1x5C compared to 2x5C (P<0.05), with no difference between the latter two (P>0.05). Absolute reliability was strong enough for both 1x5C and 2x5C to depict a true detectable change in the sample's VATMS following the fatiguing exercise (TEM < 3% at rest, <9% post-exercise) but 2x5C was marginally more sensitive to individual's changes from baseline., Conclusion: Both 1x5C and 2x5C provide reliable measures of VATMS. However, 1x5C may hold stronger internal validity. Both protocols allow detection of 'true' changes in sample's means but not individual scores following a fatiguing isometric exercise., Competing Interests: The authors have declared that no competing interests exist.

Purpose: Cooling sensations elicited by mouth rinsing with L-menthol have been reported as ergogenic. Presently, responses to L-menthol mouth rinsing during intermittent sprint performance (ISP) in the heat are unknown and the impact of increased thermal perception on ISP via capsaicin has also not been quantified. This experiment aimed to identify whether eliciting cooling/warming sensations via L-menthol/capsaicin would alter ISP in the heat., Method: Fourteen participants (mass = 72 ± 9 kg, [Formula: see text] = 3.30 ± 0.90 L min -1 ), undertook four experimental trials, involving 40 min of ISP in hot conditions (40.2 ± 0.6 °C, 42 ± 2% R.H.) with mouth rinsing (25 mL, 6 s) at the protocol onset, and every 10 min thereafter. Cooling (0.01% L-menthol; MEN), warming (0.2% capsaicin; CAP), placebo (0.3 sham-CHO; PLA), and control (water; CON) mouth rinses were utilized. Performance was quantified via power (PP) and work done (WD) during sprints. Heart rate (HR), core (T rec ) and skin (T skin ) temperature, perceived exertion (RPE), thermal sensation (T sens ), and comfort (T com ) were measured at 10 min intervals. Sweat rate (whole-body sweat rate) was calculated from ∆mass., Result: PP reduced over time (P < 0.05); however, no change was observed between trials for PP or WD (P > 0.05). T com increased over time and was lower in MEN (2.7 ± 1.1; P < 0.05) with no difference between CAP (3.1 ± 1.2), PLA (3.2 ± 1.3) and CON (3.1 ± 1.3). RPE, T sens HR, T rec , and T skin increased over time (P < 0.05) with no between trial differences (P > 0.05)., Conclusion: Despite improved thermal comfort via L-menthol, ISP did not improve. Capsaicin did not alter thermal perception or ISP. The reduction in ISP over time in hot conditions is not influenced by thermal perception.

During dual-task gait, changes in the stride-to-stride variability of stride time (STV) are suggested to represent the allocation of cognitive control to walking [1]. However, contrasting effects have been reported for overground and treadmill walking, which may be due to differences in the relative difficulty of the dual task. Here we compared the effect of overground and treadmill dual-task walking on STV in 18 healthy adults. Participants walked overground and on a treadmill for 120s during single-task (walking only) and dual-task (walking whilst performing serial subtractions in sevens) conditions. Dual-task effects on STV, cognitive task (serial subtraction) performance and perceived task difficulty were compared between walking modalities. STV was increased during overground dual-task walking, but was unchanged during treadmill dual-task walking. There were no differences in cognitive task performance or perceived task difficulty. These results show that gait is controlled differently during overground and treadmill dual-task walking. However, these differences are not solely due to differences in task difficulty, and may instead represent modality dependent control strategies., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Purpose: Observation of a model performing fast exercise improves simultaneous exercise performance; however, the precise mechanism underpinning this effect is unknown. The aim of the present study was to investigate whether the speed of the observed exercise influenced both upper body exercise performance and the activation of a cortical action observation network (AON)., Method: In Experiment 1, 10 participants completed a 5 km time trial on an arm-crank ergometer whilst observing a blank screen (no-video) and a model performing exercise at both a typical (i.e., individual mean cadence during baseline time trial) and 15% faster than typical speed. In Experiment 2, 11 participants performed arm crank exercise whilst observing exercise at typical speed, 15% slower and 15% faster than typical speed. In Experiment 3, 11 participants observed the typical, slow and fast exercise, and a no-video, whilst corticospinal excitability was assessed using transcranial magnetic stimulation., Results: In Experiment 1, performance time decreased and mean power increased, during observation of the fast exercise compared to the no-video condition. In Experiment 2, cadence and power increased during observation of the fast exercise compared to the typical speed exercise but there was no effect of observation of slow exercise on exercise behavior. In Experiment 3, observation of exercise increased corticospinal excitability; however, there was no difference between the exercise speeds., Conclusion: Observation of fast exercise improves simultaneous upper-body exercise performance. However, because there was no effect of exercise speed on corticospinal excitability, these results suggest that these improvements are not solely due to changes in the activity of the AON.

In a number of studies in which a dual-task gait paradigm was used, researchers reported a relationship between cognitive function and gait. However, it is not clear to what extent these effects are dependent on the type of cognitive and walking tasks used in the dual-task paradigm. This study examined whether stride-time variability (STV) and trunk range of motion (RoM) are affected by the type of cognitive task and walking speed used during dual-task gait. Participants walked at both their preferred walking speed and at 25% of their preferred walking speed and performed a serial subtraction and a working memory task at both speeds. Although both tasks significantly reduced STV at both walking speeds, there was no difference between the two tasks. Trunk RoM was affected by the walking speed and type of cognitive task used during dual-task gait: Mediolateral trunk RoM was increased at the slow walking speed, and anterior-posterior trunk RoM was higher only when performing the serial subtraction task at the slow walking speed. The reduction of STV, regardless of cognitive-task type, suggests that healthy adults may redirect cognitive processes away from gait toward cognitive-task performance during dual-task gait.

The relationship between cognition and gait is often explored using a dual-task gait paradigm, which represents the ability to divide cognitive resources during walking. Recent evidence has suggested that the prefrontal cortex is involved in the allocation of cognitive resources during dual-task gait, though its precise role is unclear. Here, we used anodal and cathodal transcranial direct current stimulation (tDCS) to probe the role of the prefrontal cortex in the control of stride time variability (STV), trunk RoM and cognitive task performance during dual-task gait. As task difficulty has been shown to mediate the dual-task cost, we also manipulated walking speed to see whether the effects of tDCS on dual-task gait were influenced by walking difficulty. Ten adults performed a serial subtraction task when walking at either preferred walking speed or 25 % of preferred walking speed, before and after receiving tDCS of the left prefrontal cortex. Anodal tDCS reduced STV and the dual-task cost on STV and improved cognitive task performance. Cathodal tDCS increased STV and appeared to increase the dual-task cost on STV, but did not affect cognitive task performance. There was no effect of tDCS on trunk RoM, and the effects of tDCS were not mediated by walking speed. The effect of dual-task gait on stride time variability and cognitive task performance was altered by the application of tDCS, and these effects were polarity dependent. These results highlight the role of the prefrontal cortex in biasing task performance during dual-task gait and indicate that tDCS may be a useful tool for examining the role of the cortex in the control of dual-task gait.