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This study aimed to examine the concurrent performance of working memory and cortical activity during acute aerobic exercise in young adults. In a crossover study design, 27 young adults (mean age = 22.7 ± 3.4 years, 15 women) participated in two experimental conditions in a randomized order: (1) sitting condition (without exercise) and (2) cycling condition (moderate-intensity exercise). Working memory was measured with a modified version of the n-back task. A functional near-infrared spectroscopy (fNIRS) was used to measure cortex activation. In the cycling condition, response time (RT) for the n-back task was significantly faster (p < 0.05). No differencesd in accuracy were observed between the sitting and cycling conditions. The fNIRS results showed that the oxygenated hemoglobin (oxy-Hb) concentrations in the bilateral frontopolar area (p < 0.05), dorsolateral prefrontal cortex (p < 0.05), and right premotor and supplementary cortex (p < 0.05) were decreased while cycling. The findings indicated that the concurrent performance of working memory was improved during acute aerobic exercise, whereas cortical activity was decreased in some brain regions. [ABSTRACT FROM AUTHOR]

Background: Carbohydrates are an important fuel for optimal exercise performance during moderate- and high-intensity exercise; however, carbohydrate ingestion during high-intensity exercise may cause gastrointestinal upset. A carbohydrate oral rinse is an alternative method to improve exercise performance in moderate- to high-intensity exercise with a duration of 30–75 min. This is the first systematic review and meta-analysis to comprehensively examine the isolated effect of maltodextrin-based rinsing on exercise performance. Objective: The objective of this review was to establish the effect of a maltodextrin-based carbohydrate oral rinse on exercise performance across various modes of exercise. Furthermore, a secondary objective was to determine the effects of moderators [(1) participant characteristics; (2) oral rinse protocols; (3) exercise protocol (i.e. cycling, running etc.) and (4) fasting] on exercise performance while using a maltodextrin-based, carbohydrate oral rinse. Methods: Five databases (MEDLINE, PsycINFO, Embase, SPORTDiscus and Global Health) were systematically searched for articles up to March 2021 and screened using Covidence (a systematic review management tool). A random effects robust meta-analysis and subgroup analyses were performed using Stata Statistical Software: Release 16. Results: Thirty-five articles met the inclusion criteria and were included in the systematic review; 34 of these articles were included in the meta-analysis. When using a conventional meta-analytic approach, overall, a carbohydrate oral rinse improved exercise performance in comparison with a placebo (SMD = 0.15, 95% CI 0.04, 0.27; p = 0.01). Furthermore, when implementing an adjusted, conservative, random effects meta-regression model using robust variance estimation, overall, compared with placebo, a carbohydrate oral rinse demonstrated evidence of improving exercise performance with a small effect size (SMD = 0.17, 95% CI − 0.01, 0.34; p = 0.051). Conclusion: This systematic review and meta-analysis demonstrates that a maltodextrin-based carbohydrate oral rinse can improve exercise performance. When comparing the two meta-analytic approaches, although non-significant, the more robust, adjusted, random effects meta-regression model demonstrated some evidence of a maltodextrin-based carbohydrate oral rinse improving exercise performance overall. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the effects of caffeine ingestion on muscular performance during the early-follicular and mid-luteal phases of the menstrual cycle. Fourteen resistance-trained naturally menstruating women performed countermovement jump (CMJ), maximal voluntary isometric contraction (MVIC), one-repetition maximum (1-RM), and repetitions-to-failure (RF) at 80% of 1-RM in the half-squat exercise, in early-follicular and mid-luteal phases, after placebo or caffeine ingestion. The early-follicular and mid-luteal phases were identified via calendar-based counting method. The MVIC was lower in the early-follicular than mid-luteal phase (–6.2 ± 15.2 N, p < 0.05) and higher with caffeine than placebo ingestion regardless of the menstrual cycle phase (+16.8 ± 26.7 N, p < 0.05). The magnitude of gains (supplement x phase interaction, p < 0.026) in 1-RM, CMJ, and RF with caffeine ingestion was higher in the early-follicular (+16.6 ± 7.1 kg, +2.5 ± 1.6 cm, and +4.5 ± 2.6 repetitions, respectively) than in the mid-luteal phase (+7.7 ± 4.8 kg, +1.5 ± 2.0 cm, and +2.4 ± 3.1 repetitions, respectively). In conclusion, the greater ergogenic effect of caffeine during the early-follicular phase supports its use to mitigate the decline in muscular performance in this phase of the menstrual cycle. [ABSTRACT FROM AUTHOR]

Background: Many investigations have been performed on the effects of mental exertion that consumes self-regulatory resources and then affects physical and/or cognitive performance later on. However, the effect of manipulating self-regulation and interventions to attenuate this negative effect remains unclear. Moreover, there is continuous controversy regarding the resource model of self-regulation. Objective: We conducted a systematic review to assess the literature on manipulating self-regulation based on four ingredients (standard, monitoring, strength, and motivation) in order to counter mental exertion and improve physical and/or cognitive performance. The results provide more insight into the resource model. Method: A thorough search was conducted to extract the relevant literature from several databases, as well as Google Scholar, and the sources from the references were included as grey literature. A self-regulation intervention compared to a control condition, a physical and/or cognitive task, and a randomised controlled trial were selected. Result: A total of 39 publications were included. Regarding the four components of self-regulation, the interventions could mainly be divided into the following: (i) standard: implementation intervention; (ii) monitoring: biofeedback and time monitoring; (iii) strength: repeated exercise, mindfulness, nature exposure, and recovery strategies; (iv) motivation: autonomy-supportive and monetary incentives. The majority of the interventions led to significant improvement in subsequent self-regulatory performance. In addition, the resource model of self-regulation and attention-restoration theory were the most frequently used theories and supported relevant interventions. Conclusion: In line with the resource model, manipulating the four components of self-regulation can effectively attenuate the negative influence of mental exertion. The conservation proposed in the strength model of self-regulation was supported in the current findings to explain the role of motivation in the self-regulation process. Future studies can focus on attention as the centre of the metaphorical resource in the model. [ABSTRACT FROM AUTHOR]

Cumulative fatigue during repetitive work is associated with occupational risk and productivity reduction. Usually, subjective measures or muscle activity are used for a cumulative evaluation; however, Industry 4.0 wearables allow overcoming the challenges observed in those methods. Thus, the aim of this study is to analyze alterations in respiratory inductance plethysmography (RIP) to measure the asynchrony between thorax and abdomen walls during repetitive work and its relationship with local fatigue. A total of 22 healthy participants (age: 27.0 ± 8.3 yrs; height: 1.72 ± 0.09 m; mass: 63.4 ± 12.9 kg) were recruited to perform a task that includes grabbing, moving, and placing a box in an upper and lower shelf. This task was repeated for 10 min in three trials with a fatigue protocol between them. Significant main effects were found from Baseline trial to the Fatigue trials (p < 0.001) for both RIP correlation and phase synchrony. Similar results were found for the activation amplitude of agonist muscle (p < 0.001), and to the muscle acting mainly as a joint stabilizer (p < 0.001). The latter showed a significant effect in predicting both RIP correlation and phase synchronization. Both RIP correlation and phase synchronization can be used for an overall fatigue assessment during repetitive work. [ABSTRACT FROM AUTHOR]

Whilst increasing mental workload has been shown to have a detrimental effect on cycling performance and more generally to increase the risk of harm, no studies have measured how mental workload changes as a function of ultra-distance cycling, indoors or outdoors. Our objective was to measure the difference in mental workload, as indicated by changes in EEG theta power, components of HRV and psychomotor vigilance and as reported using the 'NASA Task Load Index questionnaire', before and after a 5 h indoor ride and outdoor ride completed at 65% of functional threshold power. Results of the NASA-TLX indicated the mental demand of outdoor cycling to be significantly less than that of indoor cycling. There were significant differences in the PVT results between the pre and the post outdoor ride average and median response times. The slowest 10% PVT responses were significantly slower pre than post the indoor ride. There were significant differences in HRV between pre and post outdoor and indoor rides, specifically, in the average RR intervals, RMSSD (ms2), LFPower (ms2), NN50. There were modest changes in indicators of mental workload during an ultra-distance cycle ride. As such, mental workload during ultra-distance cycling is unlikely to be a contributory factor to decreases in performance or to an increased likelihood of accident and injury. [ABSTRACT FROM AUTHOR]

The issue of using transcranial direct current stimulation (tDCS) to improve sport performance has recently been a topic of interest for researchers. The purpose of this study was to examine the effect of tDCS over left dorsolateral prefrontal cortex (DLPFC) on mental fatigue and physical performance in professional swimmers. Fifteen professional swimmers were randomly assigned in a single-blinded, randomized, counterbalanced order to sham, anodal and cathodal stimulation conditions. Mental fatigue was induced by using a 60-min modified Stroop color-word task. Subjective ratings of mental fatigue were measured before and after the stroop task. The results showed that only anodal tDCS of the left DLPFC reduces adverse effects of mental fatigue in 50-meter swimming performance, whereas cathodal stimulation had no significant effect. [ABSTRACT FROM AUTHOR]

Cycling is a sport characterised by high training load, and adequate nutrition is essential for training and race performance. With the increased popularity of indoor trainers, cyclists have a unique opportunity to practice and implement key nutritional strategies. This study aimed to assess carbohydrate (CHO) intake of cyclists training or racing in this unique scenario for optimising exercise nutrition. A mixed-methods approach consisting of a multiple-pass self-report food recall and questionnaire was used to determine total CHO intake pre, during and post-training or racing using a stationary trainer and compared with current guidelines for endurance exercise. Sub-analyses were also made for higher ability cyclists (>4 W/kg functional threshold power), races v. non-races and 'key' training sessions. Mean CHO intake pre and post-ride was 0·7 (sd 0·6) and 1·0 (sd 0·8) g kg/BM and 39·3 (sd 27·5) g/h during training. CHO intake was not different for races (pre/during/post, P = 0·31, 0·23, 0·18, respectively), 'key sessions' (P = 0·26, 0·89, 0·98) or higher ability cyclists (P = 0·26, 0·76, 0·45). The total proportion of cyclists who failed to meet CHO recommendations was higher than those who met guidelines (pre = 79 %, during = 86 %, post = 89 %). Cyclists training or racing indoors do not meet current CHO recommendations for cycling performance. Due to the short and frequently high-intensity nature of some sessions, opportunity for during exercise feeding may be limited or unnecessary. [ABSTRACT FROM AUTHOR]

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Purpose: The main goal of this study was to evaluate the effectiveness of two different doses of caffeine (3 and 6 mg/kg) to enhance bar velocity during the bench press in women habituated to caffeine. Methods: Twelve recreationally trained women (age: 23.3 ± 0.8 years, body mass: 60.7 ± 5.7 kg, bench press one-repetition maximum (1RM): 44.3 ± 7.8 kg, daily caffeine ingestion: 5.7 ± 2.0 mg/kg/day) participated in a randomized double-blind experimental design. Each participant performed four different experimental sessions: after no supplementation (control, CON), after ingesting 3 and 6 mg/kg of caffeine (CAF-3 and CAF-6, respectively), or after ingesting a placebo (PLAC). In each experimental session, the participants performed 3 sets of 3 repetitions of the bench press exercise at 50% 1RM. Results: A two-way repeated-measures ANOVA with subsequent post hoc analyses indicated significant increases in peak velocity (p < 0.01; ES = 0.91) and mean velocity (p < 0.01; ES = 0.78) after the intake of CAF-6 compared to CON. The study did not show significant differences in bar velocity between CAF-6 and PLAC and between CAF-3 and PLAC. No significant differences in bar velocity were observed between CAF-3 and CAF-6 conditions. Conclusion: These results suggest that 6 mg/kg of caffeine can be an effective dose to improve power-specific training outcomes in women habituated to caffeine. However, the ergogenic effect of 6 mg/kg of caffeine may be derived from a combination of biological effects and expectancy, as this dose was only superior to the control condition with no differences over the placebo. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the repeated effect of social media on smartphones immediately before training sessions on inhibitory control (Stroop task), endurance (tethered swimming), countermovement jump (CMJ), and swimming performance (50, 100, and 400-m freestyle) in high-level female swimmers. Methods: It is a randomized and experimental investigation with parallel groups. Twenty-two participants underwent the eight weeks of the experiment. The swimmers (eight to twelve sessions per week with 15.9 ± 1.6 hours/week, and training experience of ~ 5.6 years) were randomized in two groups: control (CON, n = 11) and smartphone (SMA, n = 11). Immediately before each training session, the CON group watched videos about Olympic Games for 30-min. The SMA group used social network smartphone apps during 30-min. The inhibitory control, endurance, CMJ, and swimming performance were measured before and after the eight weeks of intervention. Results: No group x time interaction for 50-m freestyle (F(4, 18) = 1.04; p =.33; η2 = 0.09) and CMJ performance (F(4, 18) = 0.31; p =.58; η2 = 0.03) was found. Both experimental groups improved CMJ (F(2, 20) = 8.71; p =.01; η2 = 0.46). Only the CON group improved the 100-m (p =.02), 400-m freestyle (p =.01), and endurance performance (p =.01). The CON group improved the inhibitory control response (p =.01). Conclusion: It is concluded that the repeated effect of social media on smartphones immediately before swimming training sessions might reduce or nullify training gains on swimming and endurance performance. [ABSTRACT FROM AUTHOR]

We aimed to examine the effects of mental fatigue on the Yo-Yo test and Loughborough soccer passing and shooting tests performance using a meta-analysis. The search for studies was performed through eight bibliographic databases (Academic Search Elite, AUSPORT, Cochrane Library, PsycInfo, PubMed/MEDLINE, Scopus, SPORTDiscus, and Web of Science). The methodological quality of the included studies was assessed using the PEDro checklist. A random-effects meta-analysis was performed for data analysis. After reviewing 599 search results, seven studies with a total of ten groups were included in the review. All studies were classified as being of good methodological quality. Mental fatigue reduced the distance covered in the Yo-Yo test (Cohen's d: −0.49; 95% confidence interval [CI]: −0.66, −0.32). In the Loughborough soccer passing test, mental fatigue increased the original time needed to complete the test (Cohen's d: −0.24; 95% CI: −0.46, −0.03), increased penalty time (Cohen's d: −0.39; 95% CI: −0.46, −0.31), and decreased performance time (Cohen's d: −0.52; 95% CI: −0.80, −0.24). In the Loughborough soccer shooting test, mental fatigue decreased points per shot (Cohen's d: −0.37; 95% CI: −0.70, −0.04) and shot speed (Cohen's d: −0.35; 95% CI: −0.64, −0.06). Overall, the findings presented in this review demonstrated that mental fatigue negatively impacts endurance-based running performance as well as soccer passing and shooting skills. [ABSTRACT FROM AUTHOR]

Moreover, in contrast to daily experiences, where we sometimes have to engage in longer or recurring episodes of ER and emotional coping, laboratory studies on ER tend to investigate relatively short, isolated episodes of ER (in most cases - a few minutes of ER, very rarely longer than 20 min) (Webb et al., [125]). Presently, research on the effortfulness of ER is most often conducted using a "static" view of ER efficiency, where the effectiveness of ER during a particular period is averaged, and any fluctuations in its efficacy during this period are generally neglected (Webb et al., [125]). (1) To inspect the effects of effort and fatigue on ER effectiveness, it would be beneficial for studies to adopt B a dynamic view b , in which within-episode (or within-task) changes in ER effectiveness are analyzed, based on studies employing longer episodes of ER (over 20 min). Investigating if and how ER effectiveness can diminish as a result of investing effort and the resulting fatigue is crucially important, as in daily life people are often put in circumstances that routinely require prolonged, incessant or recurring engagement in ER during work (see: emotional labor research, e.g., Choi and Kim, [21]; Yang and Chen, [131]), education and self-regulated learning (Ben-Eliyahu and Linnenbrink-Garcia, [10]) as well as social interactions (including interpersonal ER; Zaki and Williams, [132]). Keywords: emotion regulation; effort; fatigue; self-control; mental fatigue; self-regulation EN emotion regulation effort fatigue self-control mental fatigue self-regulation 1 10 10 02/20/22 20220216 NES 220216 Introduction Emotion regulation (ER) refers to the processes by which individuals can influence the type of emotions they have, for how long as well as how strongly they experience and express them. [Extracted from the article]

This study investigated whether expert acrobatic gymnasts respond differentially than their non-trained counterparts during a single-legged stance task performed before and after a protocol designed to induce fatigue in the ankle plantarflexor muscles in terms of (a) postural steadiness and (b) electromyography (EMG) activation. We hypothesized that neuromuscular adaptation due to training would lead to different behavior of center of pressure (COP) and EMG quantifiers after fatigue. Twenty eight female volunteers (aged 11 to 24 years) formed two groups: expert acrobatic gymnastics athletes (GYN, n = 14) and age-matched non-gymnasts [control (CTRL), n = 14]. Fatigue of the ankle plantarflexors (dominant leg) was induced by a sustained posture (standing on the toes) until exhaustion. Traditional COP parameters (area, RMS, mean velocity, and power spectrum at low and high frequency ranges) were obtained with a force plate, and time and frequency-domain EMG parameters were obtained by surface electrodes positioned on the tibialis anterior , soleus , lateral gastrocnemius , medial gastrocnemius , vastus lateralis , biceps femoris , spinal erector and rectus abdominis muscles. The main results showed that fatigue induced a significant increase in postural oscillations in the ML axis (including RMS, velocity and frequency components of the power spectrum), with no significant effects in the AP axis. In terms of postural sway parameters (i.e., COP quantifiers), no superior balance stability was found for the GYN group as compared to CTRL, irrespective of the fatigue condition. On the other hand, the modulation of EMG parameters (in both time and frequency domains) indicated that expert acrobatic gymnastics athletes (as compared to healthy untrained matched controls) used different neuromuscular control strategies to keep their postures on single-legged quiet standing after the fatiguing protocol. The present results improve our knowledge of the mechanisms behind the interplay between fatigue and postural performance associated with the neuromuscular adaptations induced by sport practice. The design of gymnastics training might consider strategies aimed at improving the performance of specific muscles (i.e., tibialis anterior , soleus , biceps femoris , spinal erector) for which particular activation patterns were used by the acrobatic gymnastics to control single-legged quiet standing. [ABSTRACT FROM AUTHOR]

Background: Transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex (DLPFC) may reduce appetite and caloric intake and may be able to play a role as an adjunct treatment for obesity. Stimulation of this brain area is also used for the treatment of depression, which shares a common pathophysiology with obesity. As a result, the effect of tDCS on mental health and its impact on the quality of life of subjects with excess weight needs to be addressed. Objective: To assess the effect of daily tDCS of the right DLPFC on mood, daytime sleepiness, anxiety and quality of life in subjects with excess weight on a hypocaloric diet. Methods: We randomly assigned 28 subjects to receive 20 sessions of active or sham tDCS over the right DLPFC for 20 consecutive weekdays. The severity of depressive and anxiety symptoms was assessed by the Beck Depression Inventory (BDI) and the State-Trait Anxiety Inventory-State (STAI-S). Sleepiness was measured by a daytime sleepiness questionnaire (DSQ), and quality of life was measured by the 36-Item Short Form Health Survey (SF-36). Results: There were no significant changes in BDI, STAI-S and DSQ scores between groups, even after adjustments for the use of antidepressant medications and changes in body weight. There were also no significant changes in different subscales of the SF-36 quality of life questionnaire between groups. Conclusion: Repetitive tDCS on the right DLPFC is not associated with impairment in mental health or quality of life in overweight and obese subjects. [ABSTRACT FROM AUTHOR]

New Findings: What is the topic of this review?It provides an overview of the recent papers linking brain neurotransmission with exercise‐induced and/or mental fatigue.What advances does it highlight?The noradrenergic neurotransmitter system hastens central fatigue during prolonged exercise, a finding that coincides with a faster rate of increase in the rating of perceived exertion. 2) Mental fatigue affects several neurotransmitter systems, with presumably an important role for dopamine and adenosine, in multiple brain regions such as the prefrontal cortex and the anterior cingulate cortex. In sports and exercise science, fatigue is an elusive concept that has important implications in performance during exercise. It has been described in many ways (tiredness, exhaustion, lethargy or weariness) and describes a physical and/or mental state of being tired and lack of energy. Exercise‐induced fatigue can be defined as an acute impairment of exercise performance, and a distinction has been made between peripheral and central fatigue. Mental fatigue can be defined as a psychobiological state caused by prolonged exertion that has the potential to reduce cognitive performance and exercise performance. Recent studies have given clear indications that brain catecholamines are involved in the onset of fatigue during endurance exercise. Evidence is provided indicating that the noradrenergic neurotransmitter system hastens central fatigue, a finding that coincides with a faster rate of increase in the rating of perceived exertion. Brain neurotransmission is also suggested to play an important role in mental fatigue. Several neurotransmitter systems might be implicated (with the most important role for dopamine and adenosine) in multiple brain regions, such as the prefrontal cortex and the anterior cingulate cortex, and the summation of these alterations might explain the impairment in endurance performance in a mentally fatigued state. Obviously, we have to keep in mind that fatigue is a very complex construct and that, besides brain neurochemistry, several other factors play a role in its onset. [ABSTRACT FROM AUTHOR]

We studied the effects of repeated inducements of mental fatigue (MF) from using social media on smartphones immediately before training sessions by young male volleyball athletes, focusing specifically on their decision-making, endurance, and countermovement jump performance (CMJ). We pair-matched 24 participants according to their decision-making abilities and then, randomly assigned them to one of two 4-week block training groups: control (CON) and smartphone use (SMA). For a 30-minute period before each training session, the CON group watched TV and the SMA group used social media apps on smartphones. We found a significant group x time interaction effect for decision making (attack, p = 0.03; passing, p = 0.02) during training blocks. More specifically, only the CON group improved their decision making (attack, p = 0.03; passing, p = 0.02). Both groups significantly improved their CMJ performance (p =.01), with no significant group x time interaction effect for CMJ (p = 0.91). Neither group significantly improved their endurance (p = 0.56). We concluded that 30-minutes of repetitive social media app use on a smartphone immediately before 4-weeks of volleyball training sessions negatively affected decision-making in young male volleyball athletes. [ABSTRACT FROM AUTHOR]

In the last few years, a plethora of studies have explored the effects of caffeine on resistance exercise, demonstrating that this field of research is growing fast. This review evaluates and summarizes the most recent findings. Given that toxic doses of caffeine are needed to increase skeletal muscle contractility, the binding of caffeine to adenosine receptors is likely the primary mechanism for caffeine's ergogenic effects on resistance exercise. There is convincing evidence that caffeine ingestion is ergogenic for (i) one-repetition maximum, isometric, and isokinetic strength; and (ii) muscular endurance, velocity, and power in different resistance exercises, loads, and set protocols. Furthermore, there is some evidence that caffeine supplementation also may enhance adaptations to resistance training, such as gains in strength and power. Caffeine ingestion is ergogenic for resistance exercise performance in females, and the magnitude of these effects seems to be similar to that observed in men. Habitual caffeine intake and polymorphisms within CYP1A2 and ADORA2A do not seem to modulate caffeine's ergogenic effects on resistance exercise. Consuming lower doses of caffeine (e.g., 2–3 mg/kg) appears to be comparably ergogenic to consuming high doses of caffeine (e.g., 6 mg/kg). Minimal effective doses of caffeine seem to be around 1.5 mg/kg. Alternate caffeine sources such as caffeinated chewing gum, gel, and coffee are also ergogenic for resistance exercise performance. With caffeine capsules, the optimal timing of ingestion seems to be 30–60 min before exercise. Caffeinated chewing gums and gels may enhance resistance exercise performance even when consumed 10 min before exercise. It appears that caffeine improves performance in resistance exercise primarily due to its physiological effects. Nevertheless, a small portion of the ergogenic effect of caffeine seems to be placebo-driven. [ABSTRACT FROM AUTHOR]

One of the current challenges for translational rehabilitation research is to develop the strategies to deliver accurate evaluation, prediction, patient selection, and decision-making in the clinical practice. In this regard, the robot-assisted interventions have gained popularity as they can provide the objective and quantifiable assessment of the motor performance by taking the kinematics parameters into the account. Neurophysiological parameters have also been proposed for this purpose due to the novel advances in the non-invasive signal processing techniques. In addition, other parameters linked to the motor learning and brain plasticity occurring during the rehabilitation have been explored, looking for a more holistic rehabilitation approach. However, the majority of the research done in this area is still exploratory. These parameters have shown the capability to become the "biomarkers" that are defined as the quantifiable indicators of the physiological/pathological processes and the responses to the therapeutical interventions. In this view, they could be finally used for enhancing the robot-assisted treatments. While the research on the biomarkers has been growing in the last years, there is a current need for a better comprehension and quantification of the neuromechanical processes involved in the rehabilitation. In particular, there is a lack of operationalization of the potential neuromechanical biomarkers into the clinical algorithms. In this scenario, a new framework called the "Rehabilomics" has been proposed to account for the rehabilitation research that exploits the biomarkers in its design. This study provides an overview of the state-of-the-art of the biomarkers related to the robotic neurorehabilitation, focusing on the translational studies, and underlying the need to create the comprehensive approaches that have the potential to take the research on the biomarkers into the clinical practice. We then summarize some promising biomarkers that are being under investigation in the current literature and provide some examples of their current and/or potential applications in the neurorehabilitation. Finally, we outline the main challenges and future directions in the field, briefly discussing their potential evolution and prospective. [ABSTRACT FROM AUTHOR]

Introduction: A myriad of factors underlie pacing-/exhaustion-decisions that are made during whole-body endurance performance. The prefrontal cortex (PFC) is a brain region that is crucial for decision-making, planning, and attention. PFC oxygenation seems to be a mediating factor of performance decisions during endurance performance. Nowadays, there is no general overview summarizing the current knowledge on how PFC oxygenation evolves during whole-body endurance performance and whether this is a determining factor. Methods: Three electronic databases were searched for studies related to the assessment of PFC oxygenation, through near-IR spectroscopy (NIRS), during endurance exercise. To express PFC oxygenation, oxygenated (HbO2) and deoxygenated hemoglobin (HHb) concentrations were the primary outcome measures. Results: Twenty-eight articles were included. Ten articles focused on assessing prefrontal oxygenation through a maximal incremental test (MIT) and 18 focused on using endurance tasks at workloads ranging from low intensity to supramaximal intensity. In four MIT studies measuring HbO2, an increase of HbO2 was noticed at the respiratory compensation point (RCP), after which it decreased. HbO2 reached a steady state in the four studies and increased in one study until exhaustion. All studies found a decrease or steady state in HHb from the start until RCP and an increase to exhaustion. In regard to (non-incremental) endurance tasks, a general increase in PFC oxygenation was found while achieving a steady state at vigorous intensities. PCF deoxygenation was evident for near-to-maximal intensities at which an increase in oxygenation and the maintenance of a steady state could not be retained. Discussion/Conclusion : MIT studies show the presence of a cerebral oxygenation threshold (ThCox) at RCP. PFC oxygenation increases until the RCP threshold, thereafter, a steady state is reached and HbO2 declines. This study shows that the results obtained from MIT are transferable to non-incremental endurance exercise. HbO2 increases during low-intensity and moderate-intensity until vigorous-intensity exercise, and it reaches a steady state in vigorous-intensity exercise. Furthermore, ThCox can be found between vigorous and near-maximal intensities. During endurance exercise at near-maximal intensities, PFC oxygenation increases until the value exceeding this threshold, resulting in a decrease in PFC oxygenation. Future research should aim at maintaining and improving PFC oxygenation to help in improving endurance performance and to examine whether PFC oxygenation has a role in other performance-limiting factors. [ABSTRACT FROM AUTHOR]

Purpose: Carbohydrate (CHO) mouth rinsing (MR) prior to exercise has been shown to elicit enhanced performance and energy availability in some studies. Previous literature has concentrated on examining CHO MR strategies for improving aerobic endurance performance in younger athletic adults. Knowledge of the impact of CHO MR on functional performance in older adults is scarce. The purpose of this investigation was to determine if CHO MR would improve 6-min walk test (6MWT) performance, perceived exertion, and blood glucose responses in older adults. Method: Thirty-three individuals (16 males, 17 females), age ≥ 70 years performed two 6MWT trials, one of which utilized a 6.4% maltodextrin CHO MR and one of which utilized a placebo MR. Participants held the MR in their mouth for 20 s prior to the 6MWT, and trials occurred in a counterbalanced fashion. Total distance walked and rating of perceived exertion (RPE) were recorded upon completion of each 6MWT. Heart rate (HR), peripheral blood oxygen saturation (SpO2), systolic and diastolic blood pressures (BP), blood glucose, and blood lactate were measured before and after each 6MWT. Result: CHO MR did not alter the response of any study parameter compared to the placebo MR (p = 0.13–0.94). HR, systolic BP, and blood lactate increased and SpO2 decreased across time (p < 0.01). Conclusion: A 6.4% maltodextrin CHO MR did not alter total distance walked, perceived exertion, or other physiological responses elicited by the 6MWT in older adults. [ABSTRACT FROM AUTHOR]

Self-paced exercise is any physical activity in which the effort has to be distributed over time in order to achieve the objective of the event. Hence, self-paced aerobic exercise is a goal-directed behavior towards an objective that involves several cognitive processes. The aim of the present review is to ask the extent to which self-paced exercise might rely on executive functions and the empirical evidence of top-down processing on self-paced exercise. We discuss the evidence from different experimental manipulations showing a potential link between self-paced exercise and executive processing. We finally highlight some gaps in the literature and possible factors that might mediate the role of executive processing and self-paced exercise. Self-paced exercise is likely to be a highly complex process, in which a multitude of factors non-related to executive functions can also contribute to the ultimate decision to upregulate or downregulate exercise intensity. [ABSTRACT FROM AUTHOR]

Background: Mental fatigue is a psychobiological state caused by extended periods of cognitive effort, and evidence suggests that mentally fatigued athletes present impaired physical performance. Different ergogenic aids have been proposed to counteract the deleterious effects of mental fatigue, but whether brain stimulation can counteract mental fatigue is still unknown. This scenario is even more obscure considering the effects of these interventions (mental fatigue induction and brain stimulation) in a very experienced population consisting of master athletes. Method: Ten master swimmers (30 ± 6 years old and 14 ± 8 years of experience) participated in the study. They underwent four experimental conditions before an 800-m freestyle test: mental fatigue with brain stimulation; mental fatigue without brain stimulation; absence of mental fatigue with brain stimulation; and absence of mental fatigue and no brain stimulation. Mental fatigue was induced by a cognitively demanding Stroop Color Test, whereas stimulation was applied on the temporal cortex. After that, the athletes swan 800 m as fast as possible and provided their ratings of perceived exertion (RPE) every 200 m. Results: Mental fatigue was effectively induced, as evidenced by a greater fatigue perception and more errors in the last blocks of the cognitive task. Mental fatigue induction did not influence performance (time to complete the swimming trial) and RPE. Similarly, brain stimulation failed to change these two parameters, regardless of mental fatigue induction. Conclusion: The prolonged physical performance of experienced master athletes is not influenced, under the present conditions, by mental fatigue induction, cerebral stimulation, and their association. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to assess the effects of mental fatigue (MF) on the psychophysiological and cognitive responses and technical skills in small-sided games (SSGs) in amateur soccer players. Material and methods: 18 soccer players played 2vs2, 3vs3, and 4vs4 SSGs under 2 different playing conditions: MF+SSGs and SSGs. The Feeling Scale (FS), Felt Arousal Scale (FAS), Visual Analogue Scale-Anxiety (VAS-A) and Motivation (MTV) were determined after each SSGs bout. A Trail-Making Test (TMT) was also determined in the beginning and at the end of each SSGs. Technical performance was continuously recorded with a camera during all SSGs. Results: The results demonstrated that MF induced higher negative psychophysiological and cognitive responses (p≤0.05, d=ranging from 0.73 to 2.78) in 2vs2 and 3vs3 SSGs compared to 4vs4 SSGs except for VAS-A and MTV responses. Furthermore, the MF intervention also induced an adverse effect on technical skills (p≤0.05, d=ranging from 0.65 to 2.50) in 2vs2 and 3vs3 SSGs compared to 4vs4 SSGs except for interception, tackle and two touches skills. Conclusions: These findings showed that MF impacted the psychophysiological and cognitive responses, and technical skills during SSGs. Coaches should take MF into account before planning SSGs. [ABSTRACT FROM AUTHOR]

Wetlands worldwide are under threat from anthropogenic impacts. In large protected North American areas such as Yellowstone and Wood Buffalo National Parks, aquatic habitats are disappearing and wetland-dependent fauna are in decline1–3. Here we investigate population dynamics of an indicator species in Canada's Peace-Athabasca Delta ("the delta"), a World Heritage Site. Based on population surveys, habitat mapping and genetic data from 288 muskrats, we use agent-based modeling and genetic analyses to explain population expansion and decline of the semi-aquatic muskrat (Ondatra zibethicus). Simulations quantify a large population (~500,000 individuals) following flood-induced habitat gains, with decreased size (~10,000 individuals) during drying. Genetic analyses show extremely low long-term effective population size (Ne: 60–127), supporting a legacy of population bottlenecks. Our simulations indicate that the muskrat population in the delta is a metapopulation with individuals migrating preferentially along riparian pathways. Related individuals found over 40 km apart imply dispersal distances far greater than their typical home range (130 m). Rapid metapopulation recovery is achieved via riparian corridor migration and passive flood-transport of individuals. Source-sink dynamics show wetland loss impacts on the muskrat metapopulation's spatial extent. Dramatic landscape change is underway, devastating local fauna, including this generalist species even in a protected ecosystem. Ward et al. investigate population dynamics of a wetland indicator species, the semi-aquatic muskrat, within the large and protected area of the Peace-Athabasca Delta in Canada. The authors found indications of rapid population increases associated with flood events, genetic signatures of population bottlenecks, long range dispersal dynamics, and declines in the spatial extent of the muskrat population indicative of the impacts of wetland loss even within a protected ecosystem. [ABSTRACT FROM AUTHOR]

The muskrat (Ondatra zibethicus) is an iconic species in Canada, valued for both its fur and its integral role in wetland ecosystems, and widely regarded for its perseverance. However, the resilience of this semiaquatic mammal seems to be in question now as increasing evidence points to widespread population declines. Recent analyses of harvest data across North America suggest a reduction in their numbers, but this has not been widely corroborated by population surveys. In this study we replicated historic muskrat house count surveys at two large Great Lakes coastal wetlands and present confirmation that declines in muskrat harvest correspond to actual declines in muskrat abundance. At the Point Pelee National Park marsh and the Matchedash Bay‐Gray Marsh wetland we found that mean muskrat house counts declined by 93% and 91% respectively between historic surveys 40–50 yrs ago and contemporary surveys over the past 7 yrs. The factors responsible for these dramatic declines remain unclear but there may be a relationship with changes in the habitat quality of these wetlands that have occurred over the same time frame. Not only is the loss of muskrats an issue for the resulting loss of the wetland ecosystem services they provide, but it may be an indication of broader marsh ecosystem degradation. As such, a scarcity of muskrats should be considered a red flag for the state of biodiversity in our wetlands. Continued surveys and ongoing research are needed to shed more light on the current status of muskrat populations and their marsh habitats across their native range. [ABSTRACT FROM AUTHOR]

In this study, the inherent antibacterial activity of 11 different polymerized ionic liquids (PILs)‐based hydrogels as well as their corresponding monomers was examined in an extensive screening. The methicillin‐resistant Staphylococcus aureus Xen 30 (MRSA Xen 30) and Pseudomonas aeruginosa Xen 5 (P. aeruginosa Xen 5) were chosen as test microorganisms. Both are typical representatives of gram‐positive and gram‐negative bacteria, respectively. Six of the 11 tested monomers were able to eradicate more than 80% of P. aeruginosa Xen 5 cells in suspension. Unfortunately, the anionic, neutral and zwitterionic representatives lost their function after polymerization. However, the cationic gels retained their antibacterial activity with nearly 100% eradication of selected microorganisms ‐ even at the smallest amount tested. Bactericidal activity against gram‐positive MRSA Xen 30 was high when the bacteria were treated with the imidazolium‐based monomers. Five of the tested compounds showed rather limited bactericidal activity <50% killed bacteria. The weak antibacterial activities could be significantly increased by crosslinking them to three‐dimensional networks. As a result, all the hydrogels possessed strong killing efficiencies of at least 68% and were able to maintain this activity even at low hydrogel volume fractions. These findings are very promising for the development of new antibacterial materials for medical applications, for example, stent coatings. [ABSTRACT FROM AUTHOR]

Muskrats Ondatra zibethicus are semiaquatic herbivores experiencing long-term and widespread population declines across North America. Translocation may be a viable tool to bolster or reestablish local populations; however, subsequent effects of translocation on muskrats are unknown. We live-trapped and translocated radiomarked muskrats (n = 65) during the summers of 2018-2019 in Voyageurs National Park, MN, USA and assessed post-translocation effects on weekly survival probabilities and space-use patterns. We did not observe homing behavior, though individuals moved an average of 2.2 km (SE = 0.30 km) from release sites and established home ranges within ~8 days (SE = 1.16 days) post-translocation. Weekly post-translocation survival probabilities (0.95, SE = 0.001) and average home-range sizes (2.52 ha, SE = 0.44 ha) were similar to other studies of non-translocated muskrats. Our most-supported known-fate survival model revealed muskrats using beaver Castor canadensis lodges had greater weekly survival probabilities. Additionally, weekly muskrat survival varied between years suggesting a positive response to a novel soft-release technique applied in 2019. Our study provides the first empirical assessment of translocation effects on muskrats and suggests translocation may be effective for establishing or enhancing local muskrat populations. Additionally, our study suggests beaver lodges may confer fitness benefits to sympatric muskrats particularly during dispersal. [ABSTRACT FROM AUTHOR]

The main purpose of this investigation was to examine influence of mental fatigue on sessional ratings of perceived exertion (sRPE) over a training week in elite athletes in open skill (OS, i.e., more unpredictable and externally paced sports) and closed skill (CS, i.e., more predictable and internally paced) sports. Visual analogue scales for mental fatigue, sRPE(CR-10 scale), and training duration were collected from an OS group (n = 27) of basketball and volleyball athletes and a CS group (n = 28) of weightlifting and track and field athletes during a typical training week 5 months before the 2016 Olympic Games. These variables were then examined using repeated measure correlations and linear mixed models with the level of significance set for the study at p < 0.05. There was a small significant correlation between mental fatigue and sRPE in the OS group (r = 0.23, p < 0.01), but not in the CS group (r = -0.07, p = 0.38). Mental fatigue had trivial influence on sRPE during individual sessions, but had a moderate effect on total sRPE over a week (p < 0.001, f² = 0.265) when accounting for type of sport, training duration, and injury/illness burden. It seems mental fatigue may not significantly influence sRPE in individual training sessions, but may potentially have a cumulative effect that may affect the sRPE over a training week. This suggests monitoring mental fatigue independently of other training load (TL) measures may be worthwhile for strength and conditioning specialists and sports coaches to manage their athletes and researchers conducting studies into TL and performance. [ABSTRACT FROM AUTHOR]

Extraverts are active and talkative, while introverts are quiet and calm. This difference has been attributed to the cortical activation level (arousal), which is low in extraverts and high in introverts. Thus, to reach an optimal level of arousal, extraverts seek stimulation and introverts avoid it. As caffeine increases arousal levels, our primary aim was to investigate the effect of caffeine on the performance of extraverted and introverted university students in the execution of stability, manipulative, and locomotor tasks. Considering the above, we evaluated side effects, such as restlessness and trembling of hands, we also analyzed the individual's perception regarding caffeine intake and the placebo. Forty two volunteers were classified as 21 extraverts and 21 introverts by the Eysenck Personality Questionnaire. Participants performed three tasks on two different days, having previously ingested caffeine and a placebo in counterbalanced order. A double-blind technique was employed. The dependent variable was the execution time to perform the tasks. The analyses of variance [2 (extraversion/introversion) x 2 (caffeine x placebo)] for each task did not show significant differences. Regarding the secondary aim, the chi-square test showed that introverts had a better perception of the substance they had ingested than did extraverts. Our findings indicate that in the execution of stability, manipulative, and locomotor tasks, either caffeine or the placebo produced the same effect, regardless of the participants' extraversion score. In addition, introverts were more sensitive to perceive which substance was ingested, caffeine or the placebo, than extraverts. [ABSTRACT FROM AUTHOR]

Taste is a homeostatic function that conveys valuable information, such as energy density, readiness to eat, or toxicity of foodstuffs. Taste is not limited to the oral cavity but affects multiple physiological systems. In this review, we outline the ergogenic potential of substances that impart bitter, sweet, hot and cold tastes administered prior to and during exercise performance and whether the ergogenic benefits of taste are attributable to the placebo effect. Carbohydrate mouth rinsing seemingly improves endurance performance, along with a potentially ergogenic effect of oral exposure to both bitter tastants and caffeine although subsequent ingestion of bitter mouth rinses is likely required to enhance performance. Hot and cold tastes may prove beneficial in circumstances where athletes' thermal state may be challenged. Efficacy is not limited to taste, but extends to the stimulation of targeted receptors in the oral cavity and throughout the digestive tract, relaying signals pertaining to energy availability and temperature to appropriate neural centres. Dose, frequency and timing of tastant application likely require personalisation to be most effective, and can be enhanced or confounded by factors that relate to the placebo effect, highlighting taste as a critical factor in designing and administering applied sports science interventions. [ABSTRACT FROM AUTHOR]

Training volume is one of the critical variables required to promote resistance training benefits (e. g., hypertrophy, muscular strength). Thus, strategies to improve training volume are required. We tested the hypothesis that there is an increase in performance and reduction in the rate of perceived exertion in strength training with caffeine supplementation, carbohydrate mouth rinse, and a synergistic effect of caffeine supplementation plus carbohydrate mouth rinse. We recruited 29 physically active women: 24±4 years, 60.0±7.9 kg, 161.0±6.0 cm. This study was a double-blind, randomized, placebo-controlled, and crossover one. The subjects performed all sessions of strength training under different conditions: caffeine (6.5 mg·kg−1 body mass); carbohydrate (6 g of maltodextrin rinsed for 10 s); caffeine plus carbohydrate; or placebo. We applied the ANOVA for repeated measures through the null-hypothesis statistical test, and the Bayes factors analyses approach. The subjects showed significant improvement in the total repetitions (P<0.01; BF10 ~99%) for both lower and upper limb exercises in all conditions compared to placebo without difference among interventions. The rate of perceived exertion (P>0.05) did not differ among interventions. However, BF10 analyses showed a higher probability of lower RPE for CAF intervention. We conclude that either caffeine supplementation or carbohydrate mouth rinse can improve performance in resistance training. There is no additional effect of caffeine plus carbohydrate. [ABSTRACT FROM AUTHOR]

Carbohydrate (CHO) mouth rinse has been shown to improve endurance performance and maintain the central drive of contracting muscles. Salt (NaCl) mouth rinse solution, often used in dentistry to desensitise the oral cavity to pain, could also activate cortical areas of the brain. Hence, the objective of this preliminary study was to investigate whether CHO (glucose) and NaCl mouth rinses could attenuate the reduction in maximum voluntary contraction (MVC) and sustained MVC (sMVC) following an endurance exercise (30-minute cycling at 70% VO2max). Ten subjects (male, age: 22 ± 1 years, weight: 65.3 ± 12.4 kg, height: 164.5 ± 7.5 cm, VO2max: 48.3 ± 6.1 mL kg−1 min−1) completed three trials of 30-minute cycling exercise. In a randomised cross-over study, in each trial, the participants rinsed using either water, 6% glucose, or 6% NaCl solution for 5 s immediately prior to and every 10 min during the cycling exercise. The MVC and sMVC were measured pre and post cycling. Analysis of variance showed significant interaction and time effects for MVC, while for sMVC there was a significant interaction with time and group effects. Both MVC and sMVC were higher post cycling in the glucose and NaCl groups compared to the water group, which suggests that activation of glucose and NaCl oral receptors could better preserve post-exercise force production. This is the first study to show that NaCl mouth rinse can produce a comparable effect on glucose. Hence, mouth rinses may be able to activate other distinct pathways that could attenuate fatigue. [ABSTRACT FROM AUTHOR]

Key points: Brief (5–6 days) adaptation to a low carbohydrate high fat diet in elite athletes increased exercise fat oxidation to rates previously observed with medium (3–4 weeks) or chronic (>12 months) adherence to this diet, with metabolic changes being washed out in a similar time frame.Increased fat utilisation during exercise was associated with a 5–8% increase in oxygen cost at speeds related to Olympic Programme races.Acute restoration of endogenous carbohydrate (CHO) availability (24 h high CHO diet, pre‐race CHO) only partially restored substrate utilisation during a race warm‐up. Fat oxidation continued to be elevated above baseline values although it was lower than achieved by 5–6 days' keto adaptation; CHO oxidation only reached 61% and 78% of values previously seen at exercise intensities related to race events.Acute restoration of CHO availability failed to overturn the impairment of high‐intensity endurance performance previously associated with low carbohydrate high fat adaptation, potentially due to the blunted capacity for CHO oxidation. We investigated substrate utilisation during exercise after brief (5–6 days) adaptation to a ketogenic low‐carbohydrate (CHO), high‐fat (LCHF) diet and similar washout period. Thirteen world‐class male race walkers completed economy testing, 25 km training and a 10,000 m race (Baseline), with high CHO availability (HCHO), repeating this (Adaptation) after 5–6 days' LCHF (n = 7; CHO: <50 g day−1, protein: 2.2 g kg−1 day−1; 80% fat) or HCHO (n = 6; CHO: 9.7 g kg−1 day−1; protein: 2.2 g kg−1 day−1) diet. An Adaptation race was undertaken after 24 h HCHO and pre‐race CHO (2 g kg−1) diet, identical to the Baseline race. Substantial (>200%) increases in exercise fat oxidation occurred in the LCHF Adaptation economy and 25 km tests, reaching mean rates of ∼1.43 g min−1. However, relative V̇O2 (ml min−1 kg−1) was higher (P < 0.0001), by ∼8% and 5% at speeds related to 50 km and 20 km events. During Adaptation race warm‐up in the LCHF group, rates of fat and CHO oxidation at these speeds were decreased and increased, respectively (P < 0.001), compared with the previous day, but were not restored to Baseline values. Performance changes differed between groups (P = 0.009), with all HCHO athletes improving in the Adaptation race (5.7 (5.6)%), while 6/7 LCHF athletes were slower (2.2 (3.4)%). Substrate utilisation returned to Baseline values after 5–6 days of HCHO diet. In summary, robust changes in exercise substrate use occurred in 5–6 days of extreme changes in CHO intake. However, adaptation to a LCHF diet plus acute restoration of endogenous CHO availability failed to restore high‐intensity endurance performance, with CHO oxidation rates remaining blunted. Key points: Brief (5–6 days) adaptation to a low carbohydrate high fat diet in elite athletes increased exercise fat oxidation to rates previously observed with medium (3–4 weeks) or chronic (>12 months) adherence to this diet, with metabolic changes being washed out in a similar time frame.Increased fat utilisation during exercise was associated with a 5–8% increase in oxygen cost at speeds related to Olympic Programme races.Acute restoration of endogenous carbohydrate (CHO) availability (24 h high CHO diet, pre‐race CHO) only partially restored substrate utilisation during a race warm‐up. Fat oxidation continued to be elevated above baseline values although it was lower than achieved by 5–6 days' keto adaptation; CHO oxidation only reached 61% and 78% of values previously seen at exercise intensities related to race events.Acute restoration of CHO availability failed to overturn the impairment of high‐intensity endurance performance previously associated with low carbohydrate high fat adaptation, potentially due to the blunted capacity for CHO oxidation. [ABSTRACT FROM AUTHOR]

Discovering any performance degradation effect of racing swimmers' use of social media smartphone apps might lead to new training and race preparation protocols, including pre-meet smartphone avoidance. This study's objective was to analyze the performance effects of using smartphone social media apps on the 50, 100, and 200-m freestyle among 25 high-level swimmers. Each participant performed the three race distances in two conditions: with smartphone app exposure (50-MF, 100-MF, and 200-MF) and without (50-CON, 100-CON, and 200-CON). We randomized the order of these two conditions across participants. While smartphone app use was not associated with statistically significant performance differences on the shortest race (50CON versus 50MF), a repeated measures ANOVA showed a significant condition × time interaction for the swimmers'100-m freestyle performance (p = 0.01), with a significantly slower performance following smartphone app use evident in the last half of this race (p = 0.02) but not in the first half (p = 0.41). We also found a condition × time interaction in the same direction (slower for swimmers who used the smartphone app) for the 200-m freestyle performance (p = 0.01), with the slower performance occurring in the second (p = 0.01) but not the first (p = 0.91), third (p = 0.07) or fourth (p = 0.06) quarters of this race. Thus, prolonged smartphone social media app use was associated with reduced performance from elite swimmers on the 100- and 200- but not the 50-m freestyle. [ABSTRACT FROM AUTHOR]

The literature to date is limited regarding the implantation of VR in healthy young individuals with a focus on cognitive function. Thirty healthy males aged between 22.8 and 24.3 years volunteered to participate in the study randomly and were assigned to one of two groups with alike exercises: an experimental group (GE, n = 15) that performed an exercise protocol with a VR game and a controlled group that performed the exercise protocol without the VR (CON, n = 15). A 128-card computerized version of the Wisconsin Card Sorting Task (WCST) and the Stroop test were completed before and after the exercise protocol. There was a significant interaction effect between time and condition for WCST preservation errors (F1,30 = 4.59, p = 0.041, η2p = 0.141) and a significant time effect for all WCST and Stroop outcomes in GE. Results of preliminary findings suggest that the use of a VR platform offers effective benefits with respect to cognitive flexibility and selective attention. In addition, participants can achieve additional benefits in cognitive flexibility by engaging in a traditional exercise protocol of a similar volume. [ABSTRACT FROM AUTHOR]

The effects of 4 mg·kg−1caffeine ingestion on strength and power were investigated for the first time, in resistance‐trained females during the early follicular phase utilizing a randomized, double‐blind, placebo‐controlled, crossover design. Fifteen females (29.8 ± 4.0 years, 63.8 ± 5.5 kg [mean ± SD]) ingested caffeine or placebo 60 minutes before completing a test battery separated by 72 hours. One‐repetition maximum (1RM), repetitions to failure (RTF) at 60% of 1RM, was assessed in the squat and bench press. Maximal voluntary contraction torque (MVC) and rate of force development (RFD) were measured during isometric knee extensions, while utilizing interpolated twitch technique to measure voluntary muscle activation. Maximal power and jump height were assessed during countermovement jumps (CMJ). Caffeine metabolites were measured in plasma. Adverse effects were registered after each trial. Caffeine significantly improved squat (4.5 ± 1.9%, effect size [ES]: 0.25) and bench press 1RM (3.3 ± 1.4%, ES: 0.20), and squat (15.9 ± 17.9%, ES: 0.31) and bench press RTF (9.8 ± 13.6%, ES: 0.31), compared to placebo. MVC torque (4.6 ± 7.3%, ES: 0.26), CMJ height (7.6 ± 4.0%, ES: 0.50), and power (3.8 ± 2.2%, ES: 0.24) were also significantly increased with caffeine. There were no differences in RFD or muscle activation. Plasma [caffeine] was significantly increased throughout the protocol, and mild side effects of caffeine were experienced by only 3 participants. This study demonstrated that 4 mg·kg−1 caffeine ingestion enhanced maximal strength, power, and muscular endurance in resistance‐trained and caffeine‐habituated females during the early follicular phase, with few adverse effects. Female strength and power athletes may consider using this dose pre‐competition and ‐training as an effective ergogenic aid. [ABSTRACT FROM AUTHOR]

The purpose of this current opinion paper is to describe the journey of ingested carbohydrate from 'mouth to mitochondria' culminating in energy production in skeletal muscles during exercise. This journey is conveniently described as primary, secondary, and tertiary events. The primary stage is detection of ingested carbohydrate by receptors in the oral cavity and on the tongue that activate reward and other centers in the brain leading to insulin secretion. After digestion, the secondary stage is the transport of monosaccharides from the small intestine into the systemic circulation. The passage of these monosaccharides is facilitated by the presence of various transport proteins. The intestinal mucosa has carbohydrate sensors that stimulate the release of two 'incretin' hormones (GIP and GLP-1) whose actions range from the secretion of insulin to appetite regulation. Most of the ingested carbohydrate is taken up by the liver resulting in a transient inhibition of hepatic glucose release in a dose-dependent manner. Nonetheless, the subsequent increased hepatic glucose (and lactate) output can increase exogenous carbohydrate oxidation rates by 40–50%. The recognition and successful distribution of carbohydrate to the brain and skeletal muscles to maintain carbohydrate oxidation as well as prevent hypoglycaemia underpins the mechanisms to improve exercise performance. [ABSTRACT FROM AUTHOR]

Research consistently suggests that loss of control (LOC) eating in children and adolescents is a key factor contributing to pediatric obesity and eating disorders. However, causes of pediatric LOC eating are yet unclear, and there is a lack of longitudinal research investigating the developmental processes contributing to LOC eating and related outcomes in youth. Physical activity is an understudied behavior that declines during middle childhood to adolescence and may exert an influence in the development of LOC eating via its impact on executive functioning. While physical activity levels and executive functioning have been linked to regulation of eating, no research has examined the mechanistic processes by which these domains may together impact LOC eating during childhood and adolescence. In the current narrative review, a model is proposed that suggests how physical activity and executive functioning influence LOC eating and related outcomes during childhood and adolescence. This model has the potential to influence future theoretical models of pediatric LOC eating and guide future prevention and intervention efforts. [ABSTRACT FROM AUTHOR]