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Shuge Zhang, Ross Roberts, Tim Woodman and Andrew Cooke

Performing to a high standard is important in sport and in many facets of life. One’s desire to perform well under high pressure typically evokes performance anxiety that often harms performance ( Woodman & Hardy, 2001 ). Conversely, while performance pressure may be detrimental to those who are

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Christopher Mesagno, Jack T. Harvey and Christopher M. Janelle

Whether self-presentation is involved in the choking process remains unknown. The purpose of the current study was to determine the role of self-presentation concerns on the frequency of choking within the context of a recently proposed self-presentation model. Experienced field hockey players (N = 45) were randomly assigned to one of five groups (i.e., performance-contingent monetary incentive, video camera placebo, video camera self-presentation, audience, or combined pressure), before taking penalty strokes in low- and high-pressure phases. Results indicated that groups exposed to self-presentation manipulations experienced choking, whereas those receiving motivational pressure treatments decreased anxiety and increased performance under pressure. Furthermore, cognitive state anxiety mediated the relationship between the self-presentation group and performance. These findings provide quantitative support for the proposed self-presentation model of choking, while also holding implications for anxiety manipulations in future sport psychology research.

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Brian Klucinec, Craig Denegar and Rizwan Mahmood

During the administration of therapeutic ultrasound, the amount of pressure at the sound head-tissue interface may affect the physiological response to and the outcome of treatment. Speed of sonification; size of the treatment area; frequency, intensity, and type of wave; and coupling media are important parameters in providing the patient with an appropriate ultrasound treatment. Pressure variations affect ultrasound transmissivity, yet pressure differences have been virtually unexplored. The purpose of this study was to assess the effects of sound head pressure on acoustic transmissivity. Three trials were conducted whereby pig tissue was subjected to increased sound head pressures using manufactured weights. The weights were added in 100 g increments, starting with 200 g and finishing with 1,400 g. Increased pressure on the transmitting transducer did affect acoustic transmissivity; acoustic energy transmission was increased from 200 g (0.44 lb) up to and optimally at 600 g (1.32 lb). However, there was decreased transmissivity from 700 to 1, 400 g (1.54 to 3.00 lb).

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Christian Maiwald, Stefan Grau, Inga Krauss, Marlene Mauch, Detlef Axmann and Thomas Horstmann

The aim of this study was to provide detailed information on rationales, calculations, and results of common methods used to quantify reproducibility in plantar pressure variables. Recreational runners (N = 95) performed multiple barefoot running trials in a laboratory setup, and pressure variables were analyzed in nine distinct subareas of the foot. Reproducibility was assessed by calculating intraclass correlation coefficients (ICC) and the root mean square error (RMSE). Intraclass correlation coefficients ranged from 0.58 to 0.99, depending on the respective variable and type of ICC. Root mean square errors ranged between 2.3 and 3.1% for relative force–time integrals, between 0.07 and 0.23 for maximum force (Fmax), and between 107 and 278 kPa for maximum pressure (Pmax), depending on the subarea of the foot. Force–time integral variables demonstrated the best within-subject reproducibility. Rear-foot data suffered from slightly increased measurement error and reduced reproducibility compared with the forefoot.

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Robin C. Jackson, Kelly J. Ashford and Glen Norsworthy

Attentional processes governing skilled motor behavior were examined in two studies. In Experiment 1, field hockey players performed a dribbling task under single-task, dual-task, and skill-focused conditions under both low and high pressure situations. In Experiment 2, skilled soccer players performed a dribbling task under single-task, skill-focused, and process-goal conditions, again under low and high pressure situations. Results replicated recent findings regarding the detrimental effect of skill-focused attention and the facilitative effect of dual-task conditions on skilled performance. In addition, focusing on movement related process goals was found to adversely affect performance. Support for the predictive validity of the Reinvestment Scale was also found, with high reinvesters displaying greater susceptibility to skill failure under pressure. Results were consistent with explicit monitoring theories of choking and are further discussed in light of the conceptual distinction between explicit monitoring and reinvestment of conscious control.

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Frank A. Treiber, Francis McCaffrey, William B. Strong, Harry Davis and Tom Baranowski

This study compared blood pressure and heart rate measurements provided by the Quinton 410 automated exercise monitor with simultaneous auscultatory and electrocardiograph readings during rest, postural change, immediately after each treadmill exercise workload, and during active recovery in a sample of young children (mean age 7.9 yrs). The Quinton 410 provided highly accurate heart rates under all conditions (average mean difference <1.0 bpm). The Quinton systolic readings correlated well with and were similar to auscultation across conditions except for the initial treadmill workload. Slightly weaker relationships were observed between the Quinton and K4 diastolic comparisons. Compared with K4 auscultatory readings, the Quinton 410 provided slightly lower diastolic pressures across conditions (average mean difference = 3.1 mmHg). These findings provide preliminary evidence that for group comparisons with children, the Quinton 410 provides acceptable blood pressure estimates resulting from a variety of events, including exercise.

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Carol A. Boliek, Reyhaneh Bakhtiari, Lauren Pedersen, Julia R. Esch and Jacqueline Cummine

pressures that subsequently influence chest wall configuration, kinematics, and inspiratory and expiratory muscular activity ( Hixon, Goldman, & Mead, 1973 ; Siafakas, Morris, & Green, 1979 ). The cortical control of chest wall muscle activity associated with maximal performance and speaking tasks is not

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Kathy J. Simpson, Eugene G. Jameson and Susan Odum

Patellofemoral dysfunctions due to abnormal force loading are significant problems for dancers. Increased jump length was predicted to require increased quadriceps force during landing, which would increase patellofemoral forces and pressures. Six female dancers performed 10 traveling jumps each at 30, 60, and 90% maximum jump displacements (JDs). A sagittal view of the landing onto a force platform (500 Hz) was filmed (100 fps). Repeated-measures ANOVA (JD) and Scheffé post hoc analyses (p < .05) showed that greater peak patellofemoral pressures occurred at longer JDs and the corresponding times to these events decreased and knee flexion increased. Previous research and these findings indicate that different regions of the patella may endure higher loads at greater JDs even though the contact areas increase with greater patellofemoral forces. However, greater knee flexion and velocity could indicate more rapid distribution of load to various patellar regions, which would reduce the time any given patellofemoral region would be subjected to high loads.

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Anne Krendl, Izzy Gainsburg and Nalini Ambady

Although the effects of negative stereotypes and observer pressure on athletic performance have been well researched, the effects of positive stereotypes on performance, particularly in the presence of observers, is not known. In the current study, White males watched a video either depicting Whites basketball players as the best free throwers in the NBA (positive stereotype), Black basketball players as the best free throwers in the NBA (negative stereotype), or a neutral sports video (control). Participants then shot a set of free throws, during which half the participants were also videotaped (observer condition), whereas the other half were not (no observer condition). Results demonstrated that positive stereotypes improved free throw performance, but only in the no observer condition. Interestingly, observer pressure interacted with the positive stereotype to lead to performance decrements. In the negative stereotype condition, performance decrements were observed both in the observer and no observer conditions.

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Wing Kai Lam, Jon P. Maxwell and Richard Masters

The efficacy of analogical instruction, relative to explicit instruction, for the acquisition of a complex motor skill and subsequent performance under pressure was investigated using a modified (seated) basketball shooting task. Differences in attentional resource allocation associated with analogy and explicit learning were also examined using probe reaction times (PRT). Access to task-relevant explicit (declarative) knowledge was assessed. The analogy and explicit learning groups performed equally well during learning and delayed retention tests. The explicit group experienced a drop in performance during a pressured transfer test, relative to their performance during a preceding retention test. However, the analogy group's performance was unaffected by the pressure manipulation. Results from PRTs suggested that both groups allocated equal amounts of attentional resources to the task throughout learning and test trials. Analogy learners had significantly less access to rules about the mechanics of their movements, relative to explicit learners. The results are interpreted in the context of Eysenck and Calvo's (1992) processing efficiency theory and Masters's (1992) theory of reinvestment.