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Katharina Geukes, Christopher Mesagno, Stephanie J. Hanrahan and Michael Kellmann

Trait activation theorists suggest that situational demands activate traits in (pressure) situations. In a comparison of situational demands of private (monetary incentive, cover story), mixed (monetary incentive, small audience), and public (large audience, video taping) high-pressure situations, we hypothesized that situational demands of private and mixed high-pressure conditions would activate self-focus traits and those of a public high-pressure condition would activate self-presentation traits. Female handball players (N = 120) completed personality questionnaires and then performed a throwing task in a low-pressure condition and one of three high-pressure conditions (n = 40). Increased anxiety levels from low to high pressure indicated successful pressure manipulations. A self-focus trait negatively predicted performance in private and mixed high-pressure conditions, and self-presentation traits positively predicted performance in the public high-pressure condition. Thus, pressure situations differed in their trait-activating situational demands. Experimental research investigating the trait–performance relationship should therefore use simulations of real competitions over laboratory-based scenarios.

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Scott W. Cheatham and Morey J. Kolber

neurological mechanism may be responsible for this crossover effect which is consistent with previous reports. 4 , 6 , 10 Other studies have measured the direct and crossover pressure pain threshold (PPT) in lower extremity muscle groups after a RM intervention. Pearcy et al 3 measured the effects of foam

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Sae Yong Lee and Jay Hertel

Context:

Altered foot dynamics due to malalignment of the foot may change plantar-pressure properties, resulting in various kinds of overuse injuries.

Objective:

To assess the effect of foot characteristics on plantar-pressure-related measures such as maximum pressure, maximum pressure–time, and pressure–time integral underneath the medial aspect of the foot during running.

Design:

Cross-sectional.

Setting:

Laboratory. Participants: 8 men and 17 women.

Main Outcome Measures:

Static non-weight-bearing rear-foot and forefoot alignment and navicular drop were measured. Plantar-pressure data were collected while subjects jogged at 2.6 m/s on a treadmill. Maximum pressure, time to maximum pressure, and pressure–time integral of the medial side of the foot were extracted for data analysis. Multiple-regression analysis was used to examine the effect of arch height and rear-foot and forefoot alignment on maximum pressure and pressure–time integral in the medial side of the foot.

Results:

In the medial rear-foot and midfoot regions, only rear-foot alignment had a significant effect on the variance of maximum pressure and pressure–time integral. There were no significant difference effects in the medial forefoot region.

Conclusion:

Rear-foot alignment was found to be a significant predictor of maximum plantar pressure and pressure–time integral in the medial rear-foot and midfoot regions. This indicates that control of rear-foot alignment may help decrease plantar pressure on the medial region of the foot, which may potentially prevent injuries associated with excessive rear-foot eversion.

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Kelly J. Ashford and Robin C. Jackson

The present study examined the effectiveness of a priming paradigm in alleviating skill failure under stress. The priming intervention took the form of a scrambled sentence task. Experiment 1: Thirty-four skilled field-hockey players performed a dribbling task in low- and high-pressure situations under single task, skill-focused, and priming conditions. Results revealed a significant increase in performance time from low to high pressure. In addition, performance in the priming condition was significantly better than in the control and skill-focused conditions. Experiment 2: Thirty skilled field-hockey players completed the same dribbling task as in Experiment 1; however, in addition to the control and skill-focused conditions, participants were allocated to either a positive, neutral, or negative priming condition. Results revealed significant improvements in performance time from the skill focus to the control to the priming condition for the positive and neutral groups. For the negative group, times were significantly slower in the priming condition. Results are discussed in terms of utilizing priming in a sporting context.

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Geir Jordet and Esther Hartman

The purpose of this study was to examine the relationships between shot valence, avoidance behavior, and performance in soccer penalty shootouts. Video analyses were conducted with all penalty shootouts ever held in the World Cup, the European Championships, and the UEFA Champions League (n = 36 shootouts, 359 kicks). Shot valence was assessed from the potential consequences of a shot outcome as follows: Shots where a goal instantly leads to victory were classified as positive valence shots and shots where a miss instantly leads to loss as negative valence shots. Avoidance behavior was defined as looking away from the goalkeeper or preparing the shot quickly (thus speeding up the wait). The results showed that avoidance behavior occurred more with negative valence shots than with positive shots and that players with negative valence shots performed worse than those with positive shots. Thus, avoidance motivation may help explain why professional athletes occasionally choke under pressure.

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M. Adoración Villarroya, José Antonio Casajús and José María Pérez

Objectives:

To compare temporal and pressure values between racewalking and normal walking (freely selected speed) and evaluate the impact of racewalking on normal walking.

Design and Participants:

Temporal and plantar-pressure values were recorded (xPression system) during normal walking and racewalking in 8 high-level racewalkers. The Wilcoxon test was used for comparisons.

Measurements:

Duration of walking and racewalking cycle phases (seconds and percentage of the cycle), peak and average pressures under the hind foot and metatarsal heads, and pressure distribution (%) among metatarsal heads.

Results and Conclusions:

Normal walking: temporal parameters similar to those described in normal gait; peak pressures higher than those described in nonracewalkers with displacement toward lateral forefoot. Racewalking: shorter cycles (important decrease of midstance phase); higher peak pressures than during normal walking in the hind foot and 4th and 5th metatarsal heads; average pressures similar to normal walking in hind foot and lower in forefoot; pressure displacement toward lateral forefoot greater than in normal walking.

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Anthony J. Lisi, Conor W. O’Neill, Derek P. Lindsey, Robert Cooperstein, Elaine Cooperstein and James F. Zucherman

This paper presents the first reported measurements of lumbar intervertebral disc pressure in vivo during spinal manipulation. A pressure transducer was inserted into the nucleus pulposus of one normal-appearing lumbar disc in an asymptomatic adult volunteer. Pressures were recorded during several body positions and maneuvers, then during spinal manipulation, and lastly during a repetition of the preintervention body positions. Baseline pressures in the prone and side-lying positions measured 110 kPa and 150 kPa, respectively. During the manipulation, pressure rose to a peak of 890 kPa over 250 ms. Immediately following, pressures in the prone and side-lying positions measured 150 kPa and 165 kPa, respectively. These data do not support the hypotheses that manipulation can reduce a herniation by decreasing intradiscal pressure, or cause a herniation by raising pressure to failure levels. Further work may lead to a better understanding of this treatment method.

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Scott W. Cheatham, Kyle R. Stull and Morey J. Kolber

without decreasing muscle performance, which may be ideal for a preexercise warm-up and postexercise cool down. 1 – 3 RM may help to attenuate decrements in muscle performance and delayed onset muscle soreness (DOMS). 1 – 3 RM may also increase posttreatment pressure pain thresholds (PPTs), 4 reduce

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Marcos Duarte and Valdimir M. Zatsiorsky

Prolonged (>30 min) unconstrained standing (PUS) was studied in 10 young healthy subjects. The usual methods of stabilographic analysis assume a random center of pressure (COP) migration. This study was based on the opposite idea and showed that during PUS, specific and consistent patterns of the COP migration can be recognized by a computer algorithm. Three COP migration patterns were found: (a) shifting, a fast displacement of the average position of COP from one region to another; (b) fidgeting, a fast and large displacement and returning of COP to approximately the same position; and (c) drifting, a slow continuous displacement of the average position of COP. A software code was written and default parameter values were chosen for recognizing COP migration patterns. For 30-min PUS the following patterns were identified: Shifting was generally observed every 316 ± 292 sec in the anterior-posterior (a-p) direction with an average shift amplitude of 17 ± 15 mm, and every 199 ± 148 sec in the medial-lateral (m-1) direction with an average shift amplitude of 22 ± 38 mm. Corresponding time intervals for fidgeting were 59 ± 15 sec in the a-p direction and 49±16 sec in the m-1 direction. The average drift-to-drift interval was 319 ± 173 sec in the a-p direction and 529 ± 333 sec in the m-1 direction.

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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.