Exploring the relationship between effort perception and poststroke fatigue

ObjectiveTo test the hypothesis that poststroke fatigue, a chronic, pathologic fatigue condition, is driven by altered effort perception.MethodsFifty-eight nondepressed, mildly impaired stroke survivors with varying severity of fatigue completed the study. Self-reported fatigue (trait and state), perceived effort (PE; explicit and implicit), and motor performance were measured in a handgrip task. Trait fatigue was measured with the Fatigue Severity Scale-7 and Neurologic Fatigue Index. State fatigue was measured with a visual analog scale (VAS). Length of hold at target force, overshoot above target force, and force variability in handgrip task were measures of motor performance. PE was measured with a VAS (explicit PE) and line length estimation, a novel implicit measure of PE.ResultsRegression analysis showed that 11.6% of variance in trait fatigue was explained by implicit PE (R = 0.34; p = 0.012). Greater fatigue was related to longer length of hold at target force (R = 0.421, p < 0.001). A backward regression showed that length of hold explained explicit PE in the 20% force condition (R = 0.306, p = 0.021) and length of hold and overshoot above target force explained explicit PE in the 40% (R = 0.399, p = 0.014 and 0.004) force condition. In the 60% force condition, greater explicit PE was explained by higher force variability (R = 0.315, p = 0.017). None of the correlations were significant for state fatigue.ConclusionTrait fatigue, but not state fatigue, correlating with measures of PE and motor performance, may suggest that altered perception may lead to high fatigue mediated by changes in motor performance. This finding furthers our mechanistic understanding of poststroke fatigue.

The Use of Polyamide Slaklines in Evaluating the Moving Speed in the Dynamic Balance and the Effort Capacity During the Education through Adventure Programs

Our study�s goal was to underline the differences between the girls� and the boys� representative in terms of age, in what concerns the moving speed and the effort perception during the dynamic balance when walking on the slackline throughout the activities specific for the Development through Education and Adventure (DEA). The results have shown the fact that the boys have a better speed movement on the slackline rather than the girls, allowing us to conclude that the boys� dynamic balance is superior to the girls� balance on both studied age categories. Perceiving the physical effort through heart rate is different according to age category when walking on the slackline for the groups of the study.

Effort Perception is Made More Accurate with More Effort and When Cooperating with Slackers

Recent research on the conditions that facilitate cooperation is limited by a factor that has yet to be established: the accuracy of effort perception. Accuracy matters because the fitness of cooperative strategies depends not just on being able to perceive others’ effort but to perceive their true effort. In an experiment using a novel effort-tracker methodology, we calculate the accuracy of human effort perceptions and show that accuracy is boosted by more absolute effort (regardless of relative effort) and when cooperating with a “slacker” rather than an “altruist”. A formal model shows how such an effort-prober strategy is likely to be an adaptive solution because it gives would-be collaborators information on when to abort ventures that are not in their interest and opt for ones that are. This serves as a precautionary measure against systematic exploitation by extortionist strategies and a descent into uncooperativeness. As such, it is likely that humans have a bias to minimize mistakes in effort perception that would commit them to a disadvantageous effort-reward relationship. Overall we find support for the idea that humans have evolved smart effort detection systems that are made more accurate by those contexts most relevant for cooperative tasks.

Comparing effort perception in individual and joint action contexts

In order to sustain cooperation, it is important that we have a sense that the distribution of efforts is fair. But how proficient are we at comparing our effort relative to that of others? Does the perception of our effort differ in individual and joint action contexts? To address these questions, we asked participants to squeeze a hand dynamometer at varying degrees of force to meet three target levels alone and with a partner. The results do not reveal a significant difference in the perception of effort between the two conditions. However, participants’ estimation of their effort skewed towards half when they made partial contribution to the target and this effect was more pronounced in the joint action. Taken together, the findings suggest that participants might have applied heuristics when perceiving their effort and in addition, expected fairness in the effortcontribution in a joint action context.

Effort perception

As the Borg rating of perceived exertion scale was not appropriate for children, investigators set about developing child-specific scales which employed numbers, words and/or images that were more familiar and understandable. Numerous studies have examined the validity and reliability of such scales as the CERT, PCERT and OMNI amongst children aged 5 to 16 years, across different modes of exercise (cycling, running, stepping, resistance exercise), protocols (intermittent vs. continuous, incremental vs. non-incremental) and paradigms (estimation vs. production). Such laboratory-based research has enabled the general conclusion that children can, especially with practise, use effort perception scales to differentiate between exercise intensity levels, and to self-regulate their exercise output to match various levels indicated by them. However, inconsistencies in the methodological approaches adopted diminish the certainty of some of the interpretations made by researchers. The scope for research in the application of effort perception in physical education and activity/health promotion is considerable.