scholarly journals Alternative shoe closure designs alter biomechanical performance during agility-based movements

2020 ◽  
Author(s):  
Moira Pryhoda ◽  
Rachel Wathen ◽  
Jay Dicharry ◽  
Kevin Shelburne ◽  
Bradley Davidson
Keyword(s):  
Mechanical Properties ◽  
Performance Measures ◽  
Performance Measure ◽  
Male Athletes ◽  
Impaired Performance ◽  
Performance Improvements ◽  
Two Measures ◽  
Ground Contact Time ◽  
Improved Performance ◽  
Consistent Performance

The objective of this research was to determine if three alternative shoe upper closures improve biomechanical performance measures relative to a standard lace closure in court-based movements. NCAA Division 1 and club-level male athletes recruited from lacrosse, soccer, tennis, and rugby performed four court-based movements: Lateral Skater Jump repeats (LSJ), Countermovement Jump repeats (CMJ), Triangle Drop Step drill (TDS), and Anterior-Posterior drill (AP). Each athlete performed the movements in four shoe upper closures: Standard Closure, Lace Replacement, Y Wrap, and Tri Strap. Ground contact time, peak eccentric rate of force development (RFD), peak concentric GRF, peak concentric COM power, eccentric work, concentric work, and movement completion time were measured. Tri Strap saw improvements in four of seven biomechanical variables during CMJ and LSJ and one variable during TDS. Lace Replacement delivered improvements in one performance measure during CMJ, LSJ, and AP, and two variables in TDS. Y Wrap improved performance in three performance measures during LSJ and impaired performance in two measures during CMJ and three measures during AP. Tri Strap provided the most consistent performance improvements across all movements. This study allowed for the mechanical properties of the shoe lower to remain consistent across designs to examine if an alternative shoe upper closure could enhance performance. Our results indicate that increased proprioception and/or mechanical properties due to the alternative closures, especially Tri Strap, improves athlete performance, which concludes that the design of the shoe upper is an essential consideration in shoe design.

Effects of Accounting-Method Choices on Subjective Performance-Measure Weighting Decisions: Experimental Evidence on Precision and Error Covariance

2005 ◽  
Vol 80 (4) ◽  
pp. 1163-1192 ◽  
Author(s):  
Ranjani Krishnan ◽  
Joan L. Luft ◽  
Michael D. Shields
Keyword(s):  
Performance Measures ◽  
Error Variance ◽  
Spillover Effects ◽  
Performance Measure ◽  
Incentive System ◽  
Experimental Setting ◽  
Error Covariance ◽  
Psychology Theory ◽  
Optimal Weighting ◽  
Similarity And Difference

Performance-measure weights for incentive compensation are often determined subjectively. Determining these weights is a cognitively difficult task, and archival research shows that observed performance-measure weights are only partially consistent with the predictions of agency theory. Ittner et al. (2003) have concluded that psychology theory can help to explain such inconsistencies. In an experimental setting based on Feltham and Xie (1994), we use psychology theories of reasoning to predict distinctive patterns of similarity and difference between optimal and actual subjective performance-measure weights. The following predictions are supported. First, in contrast to a number of prior studies, most individuals' decisions are significantly influenced by the performance measures' error variance (precision) and error covariance. Second, directional errors in the use of these measurement attributes are relatively frequent, resulting in a mean underreaction to an accounting change that alters performance measurement error. Third, individuals seem insufficiently aware that a change in the accounting for one measure has spillover effects on the optimal weighting of the other measure in a two-measure incentive system. In consequence, they make performance-measure weighting decisions that are likely to result in misallocations of agent effort.

scholarly journals Performance Effects with Injury Prevention Exercise Programmes in Male Youth Football Players: A Randomised Trial Comparing Two Interventions

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Hanna Lindblom ◽  
Markus Waldén ◽  
Martin Hägglund
Keyword(s):  
Injury Prevention ◽  
Randomised Trial ◽  
Football Players ◽  
Male Athletes ◽  
Male Youth ◽  
Link Type ◽  
Youth Football ◽  
Performance Effects ◽  
Improved Performance ◽  
Exercise Programmes

Abstract Background Increased performance from injury prevention exercise programmes (IPEPs) may affect injury risks positively and support the implementation of IPEPs. The primary aim was to study the performance effects of injury prevention exercises from two different IPEPs, the Knee Control IPEP and the further developed Knee Control+ IPEP, in youth male football players, and the secondary aim was to compare potential differences in performance effects between the IPEPs. Methods Four male youth football teams were tested for agility, hop and sprint performance at the start of the second half of the competitive season and after the end of the 8-week season. Per randomisation, two teams used Knee Control and two teams Knee Control+. Results In total, 47 players executed a median of 13 IPEP sessions (range 11–21 sessions). No improvements in performance were seen in the group as a whole. The intervention groups showed small declines in sprint and agility performance. There was a significant between-group difference in change for the 505 agility test, with improved performance in the Knee Control and worse performance in the Knee Control+ group, ΔKC vs KC+ = − 0.012 (95% CI − 0.19 to −0.04), d = 0.98. Conclusions No clinically meaningful performance effects were seen from the Knee Control or Knee Control+ IPEP in youth male athletes and no meaningful differences were seen between Knee Control and Knee Control+ regarding effects on performance tests. Trial registration ClinicalTrials.gov identifier: NCT03251404. Registered on 16 August 2017.

scholarly journals GABA Supplementation Negatively Affects Cognitive Flexibility Independent of Tyrosine

2021 ◽  
Vol 10 (9) ◽  
pp. 1807
Author(s):  
Lee Wei Lim ◽  
Luca Aquili
Keyword(s):  
Cognitive Flexibility ◽  
Task Switching ◽  
Animal Studies ◽  
Preliminary Evidence ◽  
Interactive Effects ◽  
Dopamine Synthesis ◽  
Double Blind ◽  
Performance Improvements ◽  
Two Measures ◽  
Healthy Participants

Increasing evidence, particularly from animal studies, suggests that dopamine and GABA are important modulators of cognitive flexibility. In humans, increasing dopamine synthesis through its precursor tyrosine has been shown to result in performance improvements, but few studies have reported the effects of GABA supplementation in healthy participants. We conducted a double-blind, placebo-controlled, randomized experiment to test the interactive effects of tyrosine and GABA administration on two measures of cognitive flexibility, response inhibition and task switching. A total of 48 healthy volunteers were split into four groups (placebo, tyrosine alone, GABA alone, and tyrosine and GABA combined). They completed cognitive flexibility tasks at baseline and after drug administration. We found that tyrosine alone had no impact on the measures of cognitive flexibility, whereas GABA alone and in combination with tyrosine worsened task switching. Our results provide preliminary evidence that putative increases in GABA and dopamine synthesis do not interact to affect cognitive flexibility performance.

scholarly journals Adaptive aspects of impulsivity and interactions with effects of catecholaminergic agents in the 5-choice serial reaction time task: implications for ADHD

2021 ◽  
Author(s):  
Chiara Toschi ◽  
Mona El-Sayed Hervig ◽  
Parisa Moazen ◽  
Maximilian G. Parker ◽  
Jeffrey W. Dalley ◽  
...  
Keyword(s):  
Reaction Time ◽  
Reaction Time Task ◽  
Serial Reaction Time Task ◽  
Superior Performance ◽  
Serial Reaction Time ◽  
Impaired Performance ◽  
Time Task ◽  
Serial Reaction ◽  
Behavioural Profile ◽  
Improved Performance

Abstract Background Work in humans has shown that impulsivity can be advantageous in certain settings. However, evidence for so-called functional impulsivity is lacking in experimental animals. Aims This study investigated the contexts in which high impulsive (HI) rats show an advantage in performance compared with mid- (MI) and low impulsive (LI) rats. We also assessed the effects of dopaminergic and noradrenergic agents to investigate underlying neurotransmitter mechanisms. Methods We tested rats on a variable inter-trial interval (ITI) version of the 5-choice serial reaction time task (5CSRTT). Rats received systemic injections of methylphenidate (MPH, 1 mg/kg and 3 mg/kg), atomoxetine (ATO, 0.3 mg/kg and 1 mg/kg), amphetamine (AMPH, 0.2 mg/kg), the alpha-2a adrenoceptor antagonist atipamezole (ATI, 0.3 mg/kg) and the alpha-1 adrenoceptor agonist phenylephrine (PHEN, 1 mg/kg) prior to behavioural testing. Results Unlike LI rats, HI rats exhibited superior performance, earning more reinforcers, on short ITI trials, when the task required rapid responding. MPH, AMPH and ATI improved performance on short ITI trials and increased impulsivity in long ITI trials, recapitulating the behavioural profile of HI. In contrast, ATO and PHEN impaired performance on short ITI trials and decreased impulsivity, thus mimicking the behavioural profile of LI rats. The effects of ATO were greater on MI rats and LI rats. Conclusions These findings indicate that impulsivity can be advantageous when rapid focusing and actions are required, an effect that may depend on increased dopamine neurotransmission. Conversely, activation of the noradrenergic system, with ATO and PHEN, led to a general inhibition of responding.

scholarly journals Is There an Optimal Pole Length for Double Poling in Cross Country Skiing?

2017 ◽  
Vol 33 (3) ◽  
pp. 197-202 ◽  
Author(s):  
Franziska Onasch ◽  
Anthony Killick ◽  
Walter Herzog
Keyword(s):  
Oxygen Uptake ◽  
Body Height ◽  
Metabolic Cost ◽  
Male Athletes ◽  
Double Poling ◽  
Acute Study ◽  
Ground Contact Time ◽  
Cross Country Skiing ◽  
Cross Country ◽  
The Given

The aim of this study was to determine the effects of pole length on energy cost and kinematics in cross country double poling. Seven sub-elite male athletes were tested using pole sets of different lengths (ranging between 77% and 98% of participants’ body height). Tests were conducted on a treadmill, set to a 2% incline and an approximate racing speed. Poling forces, contact times, and oxygen uptake were measured throughout the testing. Pole length was positively correlated with ground contact time (r = .57, p < .001) and negatively correlated with poling frequency (r = −.48, p = .003). Pole length was also positively correlated with pole recovery time and propulsive impulse produced per poling cycle (r = .36, p = .031; r = .35, p = .042, respectively). Oxygen uptake and pole length were negatively correlated (r = −.51, p = .004). This acute study shows that increasing pole length for double poling in sub-elite cross country skiers under the given conditions seems to change the poling mechanics in distinct ways, resulting in a more efficient poling action by decreasing an athlete’s metabolic cost.

Abstract 3429: Implementation of Electronic Medical Record Stroke Templates Increases Compliance with Stroke Performance Measures

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Crismely A Perdomo ◽  
Vepuka E Kauari ◽  
Elizabeth Suarez ◽  
Olajide Williams ◽  
Joshua Stillman ◽  
...  
Keyword(s):  
Medical Record ◽  
Electronic Medical Record ◽  
Performance Measures ◽  
New York State ◽  
Stroke Care ◽  
Performance Measure ◽  
Performance Comparison ◽  
York State Department ◽  
Free Text ◽  
And Performance

Background and Purpose The literature demonstrates how utilizing evidence-based, standardized stroke care can improve patient outcomes; however, the contribution of electronic medical record (EMR) systems may also impact outcomes by ensuring utilization and compliance with established stroke performance measures, facilitating and improving documentation requirements, and standardizing approach to care. In 2008, documentation in patients’ medical records was done in combination of paper and a template free EMR. Originally, the EMR was used for order entry, then transitioned to full electronic documentation in 2009. At that time we implemented our stroke templates and performance measures based on regulatory standards. We hypothesized that the stroke template implementation would help us achieve performance measure criteria above state benchmarks as set out by the New York State Department of Health (NYS DOH). Methods Implementation was phased in [over 18 months], initially using a template that only included neurological assessment and free text fields for stroke measures. By July 2010, existing templates were modified and additional stroke templates were implemented to meet new regulatory requirements and meaningful use criteria. Retrospective data review was conducted for performance comparison between 2008 -- one year prior to EMR/template implementation -- and 2010. In Quarter 1 of 2011 EMR was also implemented in the Emergency Department (ED). Data was reviewed for compliance with stroke measures. Results Documentation compliance substantially improved between 2008 and Quarter 1 2011: Compliance for these measures has been maintained ≥ 85% since November 2010, ≥ 90% Q1 2011 Conclusions The EMR implementation of stroke templates and performance measures can produce substantial improvement in performance measure compliance. Future steps will include automated documentation alerts to retrieve information and real time discovery of missing documentation for concurrent quality review and improvement

A Tutorial on the Use of ROC Analysis for Computer-Aided Diagnostic Systems

2005 ◽  
Vol 27 (3) ◽  
pp. 181-198 ◽  
Author(s):  
Ulrich Scheipers ◽  
Christian Perrey ◽  
Stefan Siebers ◽  
Christian Hansen ◽  
Helmut Ermert
Keyword(s):  
Performance Measures ◽  
Roc Curve ◽  
Roc Analysis ◽  
Real Life ◽  
Performance Measure ◽  
Diagnostic Systems ◽  
Life Data ◽  
Separation Threshold ◽  
Real Life Data ◽  
Computer Aided

The application of the receiver operating characteristic (ROC) curve for computer-aided diagnostic systems is reviewed. A statistical framework is presented and different methods of evaluating the classification performance of computer-aided diagnostic systems, and, in particular, systems for ultrasonic tissue characterization, are derived. Most classifiers that are used today are dependent on a separation threshold, which can be chosen freely in many cases. The separation threshold separates the range of output values of the classification system into different target groups, thus conducting the actual classification process. In the first part of this paper, threshold specific performance measures, e.g., sensitivity and specificity; are presented. In the second part, a threshold-independent performance measure, the area under the ROC curve, is reviewed. Only the use of separation threshold-independent performance measures provides classification results that are overall representative for computer-aided diagnostic systems. The following text was motivated by the lack of a complete and definite discussion of the underlying subject in available textbooks, references and publications. Most manuscripts published so far address the theme of performance evaluation using ROC analysis in a manner too general to be practical for everyday use in the development of computer-aided diagnostic systems. Nowadays, the user of computer-aided diagnostic systems typically handles huge amounts of numerical data, not always distributed normally. Many assumptions made in more or less theoretical works on ROC analysis are no longer valid for real-life data. The paper aims at closing the gap between theoretical works and real-life data. The review provides the interested scientist with information needed to conduct ROC analysis and to integrate algorithms performing ROC analysis into classification systems while understanding the basic principles of classification.

scholarly journals The acute caffeine ingestion improved performance during traditional and cluster‐based resistance training models in resistance‐trained male athletes

2021 ◽  
Vol 35 (S1) ◽  
Author(s):  
Majid Koozehchian ◽  
Amir Sarshin ◽  
Zahra Hatami Nasab ◽  
Alireza Naderi ◽  
Alireza Rahimi ◽  
...  
Keyword(s):  
Resistance Training ◽  
Caffeine Ingestion ◽  
Male Athletes ◽  
Training Models ◽  
Improved Performance

Abstract 038: American Heart Association Mission: Lifeline Breakthrough Series Collaborative Improving the Survival Rates for Out of Hospital Cardiac Arrest by Focusing on Early CPR With an Emphasis on Chest Compressions

2017 ◽  
Vol 10 (suppl_3) ◽  
Author(s):  
Charles R Siegel ◽  
Anjan Chakrabarti ◽  
Lewis Siegel ◽  
Forrest Winslow ◽  
Thomas Hall
Keyword(s):  
Cardiac Arrest ◽  
Quality Improvement ◽  
Performance Measures ◽  
Effective Diffusion ◽  
Survival Rates ◽  
Public Health Problem ◽  
Heart Association ◽  
Performance Measure ◽  
Compression Rate ◽  
Hospital Cardiac Arrest

Introduction: Out-of-hospital cardiac arrest (OHCA) remains a highly morbid public health problem. Despite improving practices and clear guidelines, mortality from this condition remains high at 90%, with survivors often suffering from poor neurologic outcomes. To determine the feasibility of quality improvement collaboratives to narrow gaps between evidence-based practice and patient care for OHCA, we conducted a pilot study of the AHA Resuscitation Collaborative. Methods: Eight emergency medical service agencies participated in the quality improvement collaborative pilot project. We identified several OHCA performance measures to assess the quality of care, guide collaborative activities, and monitor change in performance over time. Over the course of four learning sessions, participants were trained in quality improvement and performance measurement, analyzed performance measure results, and shared successes and challenges. Results: Five remaining agencies underwent the process outlined in Figure 1. Adherence to performance measures, including compression rate compliance (Figure 2), improved over the course of the collaborative. Compression rate compliance in Figure 2 corresponds to the process improvement efforts of the Chesapeake Fire Department with achievement of goals for optimal range of chest compression rate between 100 and 120 compressions per minute during resuscitations. Conclusion: As demonstrated in Virginia, the collaborative approach was an effective framework to improve OHCA care. Improvement in performance measures, the evident commitment of dedicated peers and colleagues, consistent collaboration, and the effective diffusion of best practices all support the continued use of this model.

Team Incentives and Bonus Floors in Relational Contracts

2020 ◽  
Vol 95 (6) ◽  
pp. 181-212
Author(s):  
Jonathan C. Glover ◽  
Hao Xue
Keyword(s):  
Performance Measures ◽  
Team Performance ◽  
Performance Measure ◽  
Relational Self ◽  
Relational Contracts ◽  
Optimal Contract ◽  
Agent Model ◽  
Strategic Complementarity ◽  
Multi Agent ◽  
The Individual

ABSTRACT Teamwork and team incentives are increasingly prevalent in modern organizations. Performance measures used to evaluate individuals' contributions to teamwork are often non-verifiable. We study a principal-multi-agent model of relational (self-enforcing) contracts in which the optimal contract resembles a bonus pool. It specifies a minimum joint bonus floor the principal is required to pay out to the agents, and gives the principal discretion to use non-verifiable performance measures to both increase the size of the pool and to allocate the pool to the agents. The joint bonus floor is useful because of its role in motivating the agents to mutually monitor each other by facilitating a strategic complementarity in their payoffs. In an extension section, we introduce a verifiable team performance measure that is a noisy version of the individual non-verifiable measures, and show that the verifiable measure is either ignored or used to create a conditional bonus floor.

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