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Martina Navarro, Nelson Miyamoto, John van der Kamp, Edgard Morya, Ronald Ranvaud and Geert J.P. Savelsbergh

We investigated the effects of high pressure on the point of no return or the minimum time required for a kicker to respond to the goalkeeper’s dive in a simulated penalty kick task. The goalkeeper moved to one side with different times available for the participants to direct the ball to the opposite side in low-pressure (acoustically isolated laboratory) and high-pressure situations (with a participative audience). One group of participants showed a significant lengthening of the point of no return under high pressure. With less time available, performance was at chance level. Unexpectedly, in a second group of participants, high pressure caused a qualitative change in which for short times available participants were inclined to aim in the direction of the goalkeeper’s move. The distinct effects of high pressure are discussed within attentional control theory to reflect a decreasing efficiency of the goal-driven attentional system, slowing down performance, and a decreasing effectiveness in inhibiting stimulus-driven behavior.

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Juan C. Chicote, Juan V. Durá, Juan M. Belda and Rakel Poveda

Principal component analysis and functional regression are combined in a model to analyze a time series of pressure maps. The model is tested measuring the pressures over a chair seat while a subject performs a combination of simple movements. A sampling rate of 3 Hz is adequate for applying the model in sitting postures. The model is able to detect patterns of movement over time, although more variables are necessary if the movements produce similar pressure distributions.

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Karen L. Nau, Victor L. Katch, Robert H. Beekman and Macdonald Dick II

Intraarterial blood pressure (BP) response to bench press weight lifting (WL) was evaluated in 11 children. Aortic systolic and diastolic pressures and heart rate (HR) were measured during WL. Baseline systolic and diastolic pressures were 120 and 81 mmHg, and HR was 86 bpm. Subjects lifted to voluntary fatigue weights equaling 60, 75, 90, and 100% of their predetermined one-repetition maximum (1RM). For each weight lifting condition, BP and HR increased as more repetitions were completed. Peak systolic pressure was 168, 177, 166, and 162 mmHg, peak diastolic pressure was 125, 139, 133, and 130 mmHg, and peak heart rate was 142, 148, 142, and 139 bpm at 60, 75, 90, and 100% 1RM, respectively. Peak BP and HR were greater during WL than rest but did not differ between conditions. The relative BP response to WL in children was similar to adult values. For all conditions, pressures increased as more repetitions were completed. It was concluded that peak pressures occur at voluntary fatigue, independent of the combination of resistance and repetitions used to achieve fatigue.

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Sandra K. Knecht, Wayne A. Mays, Yvette M. Gerdes, Randal P. Claytor and Timothy K. Knilans

The aim of this study was to provide a normal reference for arm–leg blood pressure gradients in normal pediatric and young-adult patients before and after exercise. We assessed 216 normal participants by physical or echocardiographic exam, maximally tested using the James Cycle Protocol, with arm and leg blood pressures taken pre- and postexercise. Arm–leg gradients significantly increased from –5 mmHg at rest to 4, 2, and 1 mmHg 1, 3, and 4 min postexercise (p < .05). There was a small, statistically significant increase in arm-leg blood pressure with exercise, which is probably clinically insignificant. These data serve as a normal reference.

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Column-editor : Martin A. Fees

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Justine J. Reel, Sonya SooHoo, Trent A. Petrie, Christy Greenleaf and Jennifer E. Carter

Previous research with female athletes has yielded equivocal findings when comparing disordered eating rates to nonathlete populations, but the rates differ for athletes in leanness and nonleanness sports (Sherman & Thompson, 2009). The purpose of the current study was to develop a measure to assess sport-specific weight pressures for female athletes. Secondly, this study identified frequencies of weight, size, and appearance pressures across sports. Participants (N =204) were female Division I athletes from three universities who represented 17 sports. Exploratory factor analysis yielded a 4-factor solution for the 16-item Weight Pressures in Sport for Females (WPS-F) scale with strong internal consistency (Cronbach’s alpha of 0.90). The most frequently reported pressures among female college athletes were teammates (36.8%), uniform (34.3%), and coach (33.8%). These findings are discussed in comparison with previous research along with clinical and research implications for using the WPS-F in sport psychology settings.

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Roger Bartlett, Erich Müller, Christian Raschner, Stefan Lindinger and Caroline Jordan

The aim of this study was to compare the plantar pressures and forces recorded from both feet of two groups of javelin throwers of different performance levels, in order to investigate differences between skill levels. The study was carried out using an EMED insole system on a Tartan javelin runway at the University of Innsbruck, Austria. Most of the differences (at p < .01) between the two groups were found in the two foot contacts during the delivery stride. Higher maximum total forces (forces on the whole foot) and maximum pressures were recorded for the more skilled or club throwers during the right foot contact at the beginning of this stride. For the left foot landing before release, the club throwers exhibited higher overall maximum forces and overall pressures (the largest forces and pressures recorded on any of the different foot regions) than the novices. The differences between the groups in the medial forefoot region contributed significantly to this result.

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Mark Otten

Choking research in sport has suggested that an athlete's tendency to choke, versus give a better than usual (i.e., “clutch”) performance depends on his or her personality, as well as on situational influences, such as a reliance on explicit (versus implicit) knowledge when pressured. The current study integrated these hypotheses and tested a structural equation model (SEM) to predict sport performance under pressure. Two hundred and one participants attempted two sets of 15 basketball free throws, and were videotaped during their second set of shots as a manipulation of pressure. Results of the model suggest that “reinvesting” attention in the task leads to greater anxiety (cognitive and somatic), which then predicts a higher level of self-focus; self-focus, then, did not lead to improved performance under pressure, whereas feelings of self-reported “perceived control” did help performance. Implications for measurement of these constructs, and their relationships with performance, are discussed.

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George A. Kelley and Kristi S. Kelley

The purpose of this study was to use the meta-analytic approach to examine the effects of exercise on resting systolic and diastolic blood pressure in children and adolescents. Twenty-five studies that included 84 groups (45 exercise, 39 control) and 3,189 subjects (1,885 exercise, 1,304 control) met the criteria for inclusion. Using a random effects model, non-significant decreases of approximately 2% were found for resting systolic (mean – SEM, –2 – 1 mmHg, 95% CI, –4 to 1 mmHg) and diastolic (mean – SEM, –1 – 1 mmHg, 95% CI, –3 to 1 mmHg) blood pressure. Greater decreases in resting systolic blood pressure were found for nonrandomized versus randomized controlled trials (p = 0.001). There was also a statistically significant association between changes in resting systolic blood pressure and initial blood pressure (r = 0.73, p < 0.001) and body weight (r = 0.64, p < 0.001). However, when limited to randomized trials, these results were no longer statistically significant. The results of this study suggest that exercise does not reduce resting systolic and diastolic blood pressure in children and adolescents. However, a need exists for additional randomized controlled trials, especially among hypertensive children and adolescents.

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Carmelo Bazzano, Lee N. Cunningham, Giustino Varrassi and Tony Falconio

The present study examined the relationships among the AAHPERD Physical Best health related physical fitness test (HRPFT) items to resting blood pressure in 80 boys and 84 girls from the Lanciano, Italy, school system. Systolic blood pressure (SBP) was significantly associated with age for both sexes. Diastolic blood pressure (DBP) for boys was found to be associated with fatness when age was held constant. To examine the relationship between blood pressure and the HRPFT, data were sorted into two groups of students passing or failing to meet the criterion-referenced standard (CRS) by 1-mile run performance and sum of skinfolds. SBP did not differ significantly between groups for either sex. Boys who failed to meet the CRS for 1-mile run performance showed a higher DBP of 4 mmHg when compared to boys who achieved the CRS. The group passing the aerobic fitness and body composition tests tended to perform better on all test items. With the possible exception of DBP for boys, it is concluded that performance on the Physical Best HRPFT is not associated with resting blood pressure in children and adolescents.