Physical effort paradox during reward evaluation and links to perceived control.

Effort expenditure not only prospectively discounts the reward associated with it but also retrospectively adds the subjective value of reward, which is known as the effort paradox. This study aimed to resolve the effort paradox during reward evaluation through the critical lens of neural dynamics and its potential moderators. In total, 40 participants completed an effort-reward task wherein they exerted varying physical efforts to obtain an opportunity to win monetary rewards by active or passive decision-making. We found that after-effects of physical effort expenditure during reward evaluation unfolded as an effort paradox over time, manifesting itself as an effort discounting effect during the reward positivity (RewP) period but as an effort enhancement effect during the late positive potential (LPP) interval. Then, we found a dynamic balance between the discounting effect and the enhancement effect such that the more effort discounted the RewP at the early stage, the more effort increased the LPP at the late stage. Moreover, we observed that the effort-reward relationship was modulated by perceived control such that it increased the reward sensitivity effect and decreased the effort discounting effect. Together, our findings provide new insights into the neural mechanisms underlying the after-effects of physical effort exertion during reward evaluation.

Physical effort modulates perceptual awareness judgment independent of level of processing.

Recent studies have emphasized the association between action and perceptual awareness, suggesting that action-related information can contribute to perceptual awareness. Given that the Level of Processing (LoP) hypothesis proposes that the emergence of awareness depends on the level of stimulus processing, the current study examines whether action impacts perceptual awareness across different processing levels. In Experiment 1, participants identified target stimuli's color (low-level task) or category (high-level task) via mouse clicks, followed by visual awareness ratings. Experiment 2 replicated the tasks using hand-grip dynamometers. Results from Experiment 1 support the LoP theory, showing a more gradual emergence of awareness for low-level features and a more dichotomous emergence for high-level features. In Experiment 2, higher reported visual awareness ratings were observed at greater physical effort, regardless of task type. These results suggest that action-related information influences reported awareness of stimuli in the same way at low- and high-level stimulus processing.

Dissociable neural after-effects of cognitive and physical effort expenditure during reward evaluation.

The reward after-effect of effort expenditure refers to the phenomenon that previous effort investment changes the subjective value of rewards when obtained. However, the neural mechanisms underlying the after-effects of effort exertion are still not fully understood. We investigated the modulation of reward after-effects by effort type (cognitive vs. physical) through the lens of neural dynamics. Thirty-two participants performed a physically or cognitively demanding task during an effort phase and then played a simple gambling game during a subsequent reward phase to earn monetary rewards while their electroencephalogram (EEG) was recorded. We found that previous effort expenditure decreased electrocortical activity during feedback evaluation. Importantly, this effort effect occurred in a domain-general manner during the early stage (as indexed by the reward positivity) but in a domain-specific manner during the later and more elaborative stage (as indexed by the P3 and delta oscillation) of reward evaluation. Additionally, effort expenditure enhanced P3 sensitivity to feedback valence regardless of effort type. Our findings suggest that cognitive and physical effort, although bearing some surface resemblance to each other, may have dissociable neural influences on the reward after-effects.

Cisplatin decreases voluntary wheel-running activity but does not impair food-motivated behavior in mice.

Cisplatin is a chemotherapeutic agent that is still commonly used to treat solid tumors. However, it has several toxic side effects due in large part to the mitochondrial damage that it induces. As this mitochondrial damage is likely to result in a decrease in the amount of metabolic energy that is available for behavioral activities, it is not surprising that fatigue develops in cancer patients treated with cisplatin. The present preclinical study was initiated to determine whether the detrimental effects of cisplatin were more pronounced on physical effort requiring a lot of energy versus effort that not only requires less energy but also procures energy in the form of food. For this purpose, mice were either trained to run in a wheel or to work for food in various schedules of food reinforcement before being treated with cisplatin. The experiments were carried out only in male mice as we had already reported that sex differences in cisplatin-induced neurotoxicities are minimal. Cisplatin was administered daily for one cycle of five days, or two cycles separated by a five-day rest. As observed in previous experiments, cisplatin drastically reduced voluntary wheel running. In contrast, when cisplatin was administered to food-restricted mice trained to work for a food reward in a progressive ratio schedule or in a fixed-interval schedule, it tended to increase the number of responses emitted to obtain the food rewards. This increase was not associated with any change in the temporal distribution of responses during the interval between two reinforcements in mice submitted to the fixed interval schedule of food reinforcement. When cisplatin was administered to food-restricted mice trained in an effort-based decision-making task in which they had to choose between working for a grain pellet with little effort and working for a preferred chocolate pellet with more effort, it decreased the total number of responses emitted to obtain food rewards. However, this effect was much less marked than the decrease in wheel running induced by cisplatin. The decrease in the effort invested in the procurement of food rewards was not associated with any change in the relative distribution of effort between low reward and high reward during the time course of the test session. These findings show that cisplatin decreases energy-consuming activities but not energy-procuring activities unless they require a choice between options differing in their cost-benefit ratio. Furthermore, they indicate that the physical dimension of fatigue is more likely to develop in cisplatin-treated individuals than the motivational dimension of fatigue.

Exercise Capacity and Biomarkers Among Children and Adolescents With Sickle Cell Disease.

BACKGROUND: Sickle cell disease is the most common genetic hemoglobinopathy globally and systemically affects body functioning, decreasing exercise capacity. OBJECTIVE: To assess exercise capacity through the 6-minute walk test (6MWT) and biomarkers in children and adolescents with sickle cell disease. MATERIALS AND METHODS: Cross-sectional study involving 20 children and adolescents from Brazil. Demographic and socioeconomic data were obtained. Baseline measurements included biomarkers (red blood cells, hemoglobin, hematocrit, white blood cells, platelets, reticulocytes, lactate dehydrogenase, creatine phosphokinase, C-reactive protein, interleukin 6, and fetal hemoglobin). The following data were obtained before, during, and after the 6MWT: heart rate, blood pressure, and peripheral oxygen saturation. RESULTS: Eighteen children and adolescents ages 5-14 years old were analyzed, 61.1% boys, 100% black or brown, and 61.1% in primary education, with low household income. The average distance walked in 6MWT was 463.8 (137.7) m, significantly less than the predicted value (P < .001). The distance of 6MWT was associated positively with age (P = .042) and inversely with reticulocyte count (P = .42) and interleukin 6 (P = .00). Age modified the effect of interleukin 6 in younger children (P = .038). CONCLUSION: Our findings suggest increased baseline levels of biomarkers of hemolysis and inflammation impact on 6MWT performance.

Effect of Flavonoids in Hawthorn and Vitamin C Prevents Hypertension in Rats Induced by Heat Exposure.

BACKGROUND: Excessive oxidative stress is associated with hypertension in professional high-temperature working conditions. Polyphenols exhibit a cardioprotective effect. Hawthorn contains high amounts of flavonoids, though its effect on hypertension protection has yet to be studied. This study aims to investigate this effect of extract of hawthorn (EH) or its combination with vitamin C (Vit. C) in rats induced by working under a hot environment. METHODS: Forty-two male rats were randomly divided into a control group under normal temperature and six treatment groups exposed at 33 ± 1 °C along with 1 h of daily treadmill running. They were orally provided with water, Vit. C (14mg/kg), EH (125, 250, and 500 mg/kg), and EH500 + Vit. C, once a day for four weeks. RESULTS: Both EH and Vit. C alone reduced the systolic and diastolic blood pressure of rats exposed to the heat environment; however, their joint supplementation completely maintained their blood pressure to the normal level throughout the experimental period. No morphological changes were found on the intima of aorta. Moreover, the co-supplementation of EH and Vit. C prevented the changes of heat exposure in inducing oxidative stress markers, such as glutathione peroxidase, catalase, total antioxidant capacity, and nitric oxide; the synergistic action was more effective than either individual treatment of EH and Vit. C. Furthermore, the administration of EH had more potent effects on increasing superoxide dismutase, IL-2, the 70 kilodalton heat shock proteins and high sensitivity C reactive protein, and decreasing serum malondialdehyde and lipofuscin in vascular tissue than those in Vit. C group. CONCLUSIONS: A strong synergistic effect of EH and Vit. C on the prevention of hypertension under heat exposure was established, as they inhibited the oxidative stress state. This study also sets up a novel intervention strategy in animal models for investigation on the early phases of hypertension induced by heat exposure.

A Heart Rate Step Function Response Method for the Evaluation of Pulse Wave Velocity as a Predictor of Major Adverse Cardio-Vascular Events.

Background and Objectives: Cardiovascular diseases are the main cause of death worldwide, and pulse wave velocity (PWV) is considered a predictor of major adverse cardiovascular events. The study intended to be helpful in finding methods for the preliminary assessment of PWV in primary care units. Materials and Methods: The study group consisted of 36 subjects (considered healthy by their own statement) from the medical field (medicine students and residents) aged between 20 and 30 years: 33.3% males and 66.7% females. Two types of measurements were carried out successively: (a) measurements with the arteriograph and (b) measurements on a treadmill effort testing system, where heart rate (HR) was measured over time as a response to step function physical effort (PE). Results: The study allowed for the highlighting of some limits which, if exceeded, can be associated with high PWV values: (i) if after a moderate PE and a resting time of at least 6 min, the HR is larger than 80 b/min; (ii) if the relaxation time in a PE test of moderate intensity is larger than 1 min; (iii) if the HR measured after the subject is raised from the supine to orthostatic position is larger than 100 b/min, and (iv) if the resting HR is larger than 80 b/min. Conclusions: Steady-state HR correlates with PWV and may be used for the preliminary assessment of PWV.

Residual Effects of Cannabis Use on Effort-Based Decision-Making.

OBJECTIVE: Acute Δ9-tetrahydrocannabinol (THC) administration in humans (Lawn etal., 2016) and rats (Silveira, Adams, Morena, Hill, & Winstanley, 2016) has been associated with decreased effort allocation that may explain amotivation during acute cannabis intoxication. To date, however, whether residual effects of cannabis use on effort-based decision-making are present and observable in humans have not yet been determined. The goal of this study was to test whether prolonged cannabis use has residual effects on effort-based decision-making in 24-hr abstinent cannabis using adults. METHOD: We evaluated performance on the Effort Expenditure for Reward Task (EEfRT) in 41 adult cannabis users (mean age = 24.63 years, 21 males) and 45 nonusers (mean age = 23.90 years, 19 males). A mixed 2x3x3 ANOVA with age as a covariate was performed to examine the effect of group, probability of winning, and reward amount on EEfRT performance. EEfRT performance was operationalized as % of trials for which the hard (vs. easy) condition was chosen. Pearson's correlations were conducted to test the relationship between EEfRT performance and measures of cannabis use, anhedonia and motivation. RESULTS: We found that cannabis users selected hard trials significantly more than nonusers regardless of win probability or reward level. Frequency of cannabis use was positively correlated with amount of % hard trials chosen. There were no significant correlations between % hard trials chosen, self-reported anhedonia, or motivation. CONCLUSIONS: These results suggest that unlike acute effects, residual effects of cannabis following 24 hrs of abstinence are associated with greater effort allocation during effort-based decision-making.

Exercising under particulate matter exposure: Providing theoretical support for lung deposition and its relationship with COVID-19.

The aim of the present study was to investigate lung particulate matter (PM) deposition during endurance exercise and provide a new insight concerning how SARS-CoV-2 could be carried into the respiratory tract. The anatomical and physiological characteristics of the Human Respiratory Tract model were considered for modeling the lung PM deposition during exercise. The Monte Carlo method was performed to randomly generate different values of PM concentrations (1.0, 2.5, and 10.0 µm), minute ventilation, and duration of exercise at moderate, heavy, and severe exercise intensity domains. Compared to moderate and severe intensities, during heavy exercise (75-115 L‧min-1, duration of 10.0-60.0 min) there is greater lung deposition in the bronchiolar region (p < 0.01). In turn, there is greater deposition per minute of exercise at the severe intensity domain (115.0-145.0 L‧min-1, duration of 10.0-20.0 min, p < 0.01). Considering that SARs-CoV-2 could be adsorbed on the particles, exercising under PM exposure, mainly at the severe domain, could be harmful concerning the virus. In conclusion, beyond the traditional minute ventilation assumption, there is a time vs intensity dependence for PM deposition, whereby the severe domain presents greater deposition per minute of exercise. The results observed for PM deposition are alarming since SARs-CoV-2 could be adsorbed by particles and carried into the deeper respiratory tract.

Post-exercise cognitive testing to assess persisting alterations in athletes with a history of concussion.

Primary Objective: To determine whether a physical exercise protocol could reveal persistent cognitive alterations in university athletes with a history of concussion (HOC). Thirty-four HOC and 34 controls participated in this study.Research Design: Cross-sectional.Methods and Procedures: The exercise protocol consisted of a 20-min bout on a stationary bike at 80% of the theoretical maximal heart rate. Before and after the exercise, participants performed a computerized switch task designed specifically to recruit executive functions. Group × Condition (pre- and post-exercise) repeated measures of ANCOVAs for accuracy, reaction time, and inverse efficiency score on the switch task were conducted. Chi-square tests were run to determine if the proportion of HOC and controls who underperformed (at least 2SD lower than the control group's average score) at rest and post-exercise were similar. Whilst no interaction or main effects were found with ANCOVAs, significantly more HOC athletes (21%) underperformed following exercise than at rest (3%) on the switch task, p = .02. The current results indicate that an acute bout of exercise can reveal persistent alterations that are not present at rest in the protracted phase of concussion. They also highlight the importance of considering inter-individual differences in recovery trajectories.

Neural correlates of effort-based valuation with prospective choices.

How is effort integrated in value-based decision-making? Animal models and human neuroimaging studies primarily linked the anterior cingulate cortex (ACC) and ventral striatum (VS) to the integration of effort in valuation. Other studies demonstrated the role of these regions in invigoration to effort demands, thus it is hard to separate the neural activity linked to anticipation and subjective valuation from actual performance. Here, we studied the neural basis of effort valuation separated from performance. We scanned forty participants with fMRI, while they were asked to accept or reject monetary gambles that could be resolved with future performance of a familiar grip force effort challenge or a fixed risk prospect. Participants' willingness to accept prospective gambles reflected discounting of values by physical effort and risk. Choice-locked neural activation in contralateral primary sensory cortex and ventromedial prefrontal cortex (vmPFC) tracked the magnitude of prospective effort the participants faced, independent of choice time and monetary stakes. Estimates of subjective value discounted by effort were found to be tracked by the activation of a network of regions common to valuation under risk and delay, including vmPFC, VS and sensorimotor cortex. Together, our findings show separate neural mechanisms underlying prospective effort and actual effort performance.

The effect of social network on the physical activity-cognitive function nexus in late life.

ABSTRACTBackground:To examine the contribution of vigorous physical activity to subsequent cognitive functioning, taking into account the effect of social network. METHODS: The sample included respondents aged 65 years and older who participated in both the fourth and sixth waves of Survey of Health, Ageing and Retirement in Europe (n = 17,104). Cognitive functioning in Wave 6, measured as the average of standardized scores for recall, fluency, and numeracy, was regressed on the extent of vigorous physical activity, social network size, and several confounders in Wave 4 (including the corresponding cognition score at baseline). Interaction terms for physical activity and network size were also considered. RESULTS: Moderate and high levels of vigorous physical activity, as well as social network size, were related to the cognition outcome after controlling for the confounders. Introduction of the interaction terms showed a direct and positive association of both moderate and high physical activity with the cognition outcome scores as social network size increased. However, among respondents in small- (0-1 members) and moderate-sized networks (2-3 members), greater physical activity was unrelated to the cognition score at follow-up. Only the interaction of high social connectedness (4-7 network members) and vigorous physical activity was significant. CONCLUSIONS: Vigorous physical activity is, indeed, related to subsequent cognitive functioning. However, the relationship is tempered by social network size. Therefore, interventions that increase both social connectedness and physical activity, especially among older people who are isolated and sedentary, are warranted.

Neural Signatures of Value Comparison in Human Cingulate Cortex during Decisions Requiring an Effort-Reward Trade-off.

UNLABELLED: Integrating costs and benefits is crucial for optimal decision-making. Although much is known about decisions that involve outcome-related costs (e.g., delay, risk), many of our choices are attached to actions and require an evaluation of the associated motor costs. Yet how the brain incorporates motor costs into choices remains largely unclear. We used human fMRI during choices involving monetary reward and physical effort to identify brain regions that serve as a choice comparator for effort-reward trade-offs. By independently varying both options' effort and reward levels, we were able to identify the neural signature of a comparator mechanism. A network involving supplementary motor area and the caudal portion of dorsal anterior cingulate cortex encoded the difference in reward (positively) and effort levels (negatively) between chosen and unchosen choice options. We next modeled effort-discounted subjective values using a novel behavioral model. This revealed that the same network of regions involving dorsal anterior cingulate cortex and supplementary motor area encoded the difference between the chosen and unchosen options' subjective values, and that activity was best described using a concave model of effort-discounting. In addition, this signal reflected how precisely value determined participants' choices. By contrast, separate signals in supplementary motor area and ventromedial prefrontal cortex correlated with participants' tendency to avoid effort and seek reward, respectively. This suggests that the critical neural signature of decision-making for choices involving motor costs is found in human cingulate cortex and not ventromedial prefrontal cortex as typically reported for outcome-based choice. Furthermore, distinct frontal circuits seem to drive behavior toward reward maximization and effort minimization. SIGNIFICANCE STATEMENT: The neural processes that govern the trade-off between expected benefits and motor costs remain largely unknown. This is striking because energetic requirements play an integral role in our day-to-day choices and instrumental behavior, and a diminished willingness to exert effort is a characteristic feature of a range of neurological disorders. We use a new behavioral characterization of how humans trade off reward maximization with effort minimization to examine the neural signatures that underpin such choices, using BOLD MRI neuroimaging data. We find the critical neural signature of decision-making, a signal that reflects the comparison of value between choice options, in human cingulate cortex, whereas two distinct brain circuits drive behavior toward reward maximization or effort minimization.

The oxidant-antioxidant equilibrium, activities of selected lysosomal enzymes and activity of acute phase protein in peripheral blood of 18-year-old football players after aerobic cycle ergometer test combined with ice-water immersion or recovery at room temperature.

The goal of the study was to evaluate the effect of an aerobic exercise bout followed by ice-water immersion or recovery at room temperature on the redox state, activities of selected lysosomal enzymes and activity of α1-antitrypsin (AAT) in the blood of healthy sportsmen. Eleven amateur football players aged 18 were randomly assigned to two similar 30-min aerobic cycle ergometer tests followed by a recovery at room temperature (20 °C; Experiment 1) or ice-water immersion (3 °C, 5 min; Experiment 2). Peripheral blood was collected three times during both study experiments: before (baseline), as well as 20 and 40 min after the recovery or immersion. The concentrations of thiobarbituric acid reactive substances in blood plasma (plTBARS) and erythrocytes (erTBARS) were measured. The erythrocytic activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were also determined. In the blood serum, the activities of acid phosphatase (AcP), arylsulphatase (ASA), cathepsin D (CTS D) and AAT were evaluated. The activities of AcP, ASA, CTS D and AAT changed similarly during both experiments. The GPx activity decreased 40 min after the exercise/recovery compared to the baseline activity and was lower than 40 min after the exercise/immersion. The exercise followed by the recovery or immersion had no significant effect on the serum lysosomal and AAT activities in the studied men. The exercise/recovery reduced the hydrogen peroxide concentration in the men's erythrocytes, however the exercise/immersion demonstrated the opposite effect.

[Evaluation of the effectiveness of exercise-based controlled physical effort in women with heart failure in the elderly]. / Ocena skutecznosci kontrolowanego wysilku fizycznego opartego na cwiczeniach u kobiet z niewydolnoscia serca w wieku podeszlym.

UNLABELLED: Heart failure (HF), especially during old age, significantly influences the decrease in physical fitness, depriving the patient of their independence during everyday life. The positive results of cardiac rehabilitation are one of the most well documented methods of lowering the frequency of hospitalisation and unfavourable prognosis of cardiovascular diseases. Currently complex cardiac rehabilitation is recommended by the American College of Cardiology (ACC) and American heart Association (AHA) as being an important element of treating patients with HF. However these recommendations are poorly executed in the everyday clinical practise, concerning elderly patients. AIM: The aim of study is the assessment of the efficacy of controlled physical activity in elderly women, in their VII-X decades, with stable cardiac failure, based on exercise training. MATERIALS AND METHODS: The study included a group of 55 elderly women (mean age 84.73 ± 7.13 tears) with stable heart failure, NYHA II-III. In each patient plasma concentration of B-type natriuretic peptide was measured and a 6 minute walk test (6MWT) was undertaken. RESULTS: In the study group of patients who underwent a 12 weeks of cardiac rehabilitation (72%) a decrease in level of NT-proBNP was observed after completion of physical training. The mean value decreased by 204.7pg/ml. Cardiac rehabilitation resulted in an improvement of physical fitness capacity in the group that qualified for fitness training, which was observed by an increase in distance covered during the 6MWT, initial distance of 236 (±127)m to a distance of 300.9 (±75.9)m. Furthermore using statistical analysis it was shown that in the group qualified for cardiac rehabilitation, there is a positive correlation between distance covered during the 6MWT and the improvement in clinical symptoms as measured by the NYHA classification, r=0.099, p>0.05. CONCLUSIONS: Cardiac rehabilitation modified for the individual needs and abilities of the patient is one of the significant elements that make up the complex therapy of elderly women with HF. Systematically undertaken physical activity occupies an important place in the prevention of cardiovascular disorders, by increasing the level of physical fitness, as manifested by the increase in distance covered during the 6MWT and by the change in classification of NYHA to a higher class or by the decrease in plasma concentration of NT-proBNP.

Response-dependent point loss and response force as disrupting operations on behavioral resistance to change in humans.

Behavioral momentum theory (BMT) provides a theoretical and methodological framework for understanding how differentially maintained operant responding resists disruption. A common way to test operant resistance involves contingencies with suppressive effects, such as extinction or prefeeding. Other contingencies with known suppressive effects, such as response-cost procedures arranged as point-loss or increases in response force, remain untested as disruptive events within the BMT framework. In the present set of three experiments, responding of humans was maintained by point accumulation programmed according to a multiple variable-interval (VI) VI schedule with different reinforcement rates in either of two components. Subsequently, subtracting a point following each response (Experiment 1) or increasing the force required for the response to be registered (Experiments 2 and 3 decreased response rates, but responding was less disrupted in the component associated with the higher reinforcement rate. The point-loss contingency and increased response force similarly affected response rates by suppressing responding and human persistence, replicating previous findings with humans and nonhuman animals when other types of disruptive events (e.g., extinction and prefeeding) were investigated. The present findings moreover extend the generality of the effects of reinforcement rate on persistence, and thus BMT, extending the analysis of resistance to two well-known manipulations used to reduce responding in the experimental analysis of behavior.

Effects of voluntary running on the skeletal muscle of rats with pulmonary artery hypertension.

The effects of voluntary running on the skeletal muscle of rats with pulmonary arterial hypertension (PAH) were tested in the present study. PAH was induced in rats by a single injection of monocrotaline (MCT, 60 mg/kg). Rats in the sedentary hypertension (HS) group had their tolerance to physical exertion reduced throughout the experiment, while those in the sedentary control (SC), exercise control (EC), exercise hypertension (EH) and median exercise (EM) groups maintained or increased. Despite that, the muscular citrate synthase activity was not different between groups. The survival time was higher in the EH (32 days) than in the SH (28 days) (p = 0.0032). SH and EH groups showed a lower percentage of muscle fiber and a higher percentage of extracellular matrix compared to control groups (p < 0.0001). However, the EM and EH groups presented higher percentage of muscle fiber and lower percentage of extracellular matrix than SH group (p < 0.0001). Regarding muscular gene expression, the SH and EM groups showed a lower expression of PGC1-α (p = 0.0024) and a higher expression of VEGF (p = 0.0033) compared to SC, while PGC1-α was elevated in the EH. No difference between groups was found for the carbonylated protein levels (p > 0.05), while the TNF-α/IL-10 ratio was augmented in the EH (p = 0.0277). In conclusion, voluntary running augments the proportion of fiber and affects the gene expression of inflammatory and mitochondrial biogenesis' markers in the skeletal muscle of rats with MCT-induced PAH, which benefits their survival and tolerance to physical effort.

Computational mechanisms underlying the dynamics of physical and cognitive fatigue.

The willingness to exert effort for reward is essential but comes at the cost of fatigue. Theories suggest fatigue increases after both physical and cognitive exertion, subsequently reducing the motivation to exert effort. Yet a mechanistic understanding of how this happens on a moment-to-moment basis, and whether mechanisms are common to both mental and physical effort, is lacking. In two studies, participants reported momentary (trial-by-trial) ratings of fatigue during an effort-based decision-making task requiring either physical (grip-force) or cognitive (mental arithmetic) effort. Using a novel computational model, we show that fatigue fluctuates from trial-to-trial as a function of exerted effort and predicts subsequent choices. This mechanism was shared across the domains. Selective to the cognitive domain, committing errors also induced momentary increases in feelings of fatigue. These findings provide insight into the computations underlying the influence of effortful exertion on fatigue and motivation, in both physical and cognitive domains.

Association between "cluster of differentiation 36 (CD36)" and adipose tissue lipolysis during exercise training: a systematic review.

Fatty acid translocase (FAT/CD36) is a transmembrane glycoprotein belonging to the scavenger class B receptor family and is encoded by the cluster of differentiation 36 (CD36) gene. This receptor has a high affinity for fatty acids and is involved in lipid metabolism. An abundance of FAT/CD36 during exercise occurs in mitochondria and solitary muscles. As such, we aimed to systematically review the evidence for the relationship FAT/CD36 and adipose tissue lipolysis during exercise training. Five electronic databases were selected for literature searches until June 2022: PubMed, Web of Science, Scopus, science direct, and Google Scholar. We combined the different synonyms and used the operators ("AND", "OR", "NOT"): (CD36 gene) OR (CD36 polymorphism) OR (cluster of differentiation 36) OR (FAT/CD36) OR (fatty acid translocase) OR (platelet glycoprotein IV) OR (platelet glycoprotein IIIb) AND (adipose tissue lipolysis) OR (fatty acids) OR (metabolism lipid) OR (adipocytes) AND (physical effort) OR (endurance exercise) OR (high-intensity training). All published cross-sectional, cohort, case-control, and randomized clinical trials investigating CD36 polymorphisms and adipose tissue lipolysis during exercise in subjects (elite and sub-elite athletes, non-athletes, sedentary individuals and diabetics), and using valid methods to measure FAT/CD36 expression and other biomarkers, were considered for inclusion in this review. We initially identified 476 publications according to the inclusion and exclusion criteria, and included 21 studies investigating FAT/CD36 and adipose tissue lipolysis during exercise in our systematic review after examination of titles, abstracts, full texts, and quality assessments using the PEDro scale. There were nine studies with male-only participants, three with female-only participants, and nine studies included both female and male participants. There were 859 participants in the 21 selected studies. Studies were classified as either low quality (n = 3), medium quality (n = 13), and high quality (n = 5). In general, the data suggests an association between FAT/CD36 and adipose tissue lipolysis during exercise training. Improvements in FAT/CD36 were reported during or after exercise in 6 studies, while there were no changes reported in FAT/CD36 in 4 studies. An association between fat oxidation and FAT/CD36 expression during exercise was reported in 7 studies. No agreement was reached in 5 studies on FAT/CD36 content after dietary changes and physical interventions. One study reported that FAT/CD36 protein expression in muscle was higher in women than in men, another reported that training decreased FAT/CD36 protein in insulin-resistant participants, while another study reported no differences in FAT/CD36 in young, trained individuals with type 2 diabetes. Our analysis shows an association between FAT/CD36 expression and exercise. Furthermore, an association between whole-body peak fat oxidation and FAT/CD36 expression during exercise training was demonstrated. Systematic Review Registration: [PROSPERO], identifier [CRD42022342455].

Drop-Set Resistance Training versus Pyramidal and Traditional Sets Elicits Greater Psychophysiological Responses in Men.

We compared the effects of resistance training (ResisT) to pyramidal and traditional weightlifting sets on men's psychophysiological responses. In a randomized crossover design, 24 resistance-trained males performed drop-set, descending pyramid, and traditional ResisT in the barbell back squat, 45° leg press, and seated knee extension. We assessed participants' rating of perceived exertion (RPE) and feelings of pleasure/displeasure (FPD) at the end of each set and at 10, 15, 20, and 30 minutes post-session. No differences were detected across ResisT Methods in total training volume (p = 0.180). Post hoc comparisons revealed that drop-set training elicited higher RPE (M 8.8 SD 0.7 arbitrary units) and lower FPD (M -1.4 SD 1.5 arbitrary units) values compared to descending pyramid (M Set RPE 8.0 SD 0.9 arbitrary units and M Set FPD 0.4 SD 1.6 arbitrary units) and traditional set (M Set RPE 7.5 SD 1.1 arbitrary units and M Set FPD 1.3 SD 1.2 arbitrary units) schemes (p < 0.05). In addition, drop-set training elicited higher session RPE (M 8.1 SD 0.8 arbitrary units) and lower session FPD (M 0.2 SD 1.4 arbitrary units) values than descending pyramid and traditional ResisT (p < 0.001). Similarly, descending pyramid training elicited higher session RPE (M 6.6 SD 0.9 arbitrary units) and lower session FPD (M 1.2 SD 1.4 arbitrary units) than traditional set (M Session RPE 5.9 SD 0.8 arbitrary units and M Session FPD 1.5 SD 1.2 arbitrary units) training (p = 0.015). No differences were found in the temporality of post-session metrics, suggesting that testing 10 and 15 minutes post-ResisT was sufficient to assess session RPE (p = 0.480) and session FPD (p = 0.855), respectively. In conclusion, even with similar total training volume, drop-set training elicited more pronounced psychophysiological responses than either pyramidal or traditional ResisT in resistance-trained males.