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Chris Englert, Kris Zwemmer, Alex Bertrams and Raôul R.D. Oudejans

In the current study we investigated whether ego depletion negatively affects attention regulation under pressure in sports by assessing participants’ dart throwing performance and accompanying gaze behavior. According to the strength model of self-control, the most important aspect of self-control is attention regulation. Because higher levels of state anxiety are associated with impaired attention regulation, we chose a mixed design with ego depletion (yes vs. no) as between-subjects and anxiety level (high vs. low) as within-subjects factor. Participants performed a perceptual-motor task requiring selective attention, namely, dart throwing. In line with our expectations, depleted participants in the high-anxiety condition performed worse and displayed a shorter final fixation on bull’s eye, demonstrating that when one’s self-control strength is depleted, attention regulation under pressure cannot be maintained. This is the first study that directly supports the general assumption that ego depletion is a major factor in influencing attention regulation under pressure.

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Mark R. Wilson, Samuel J. Vine and Greg Wood

The aim of this study was to test the predictions of attentional control theory using the quiet eye period as an objective measure of attentional control. Ten basketball players took free throws in two counterbalanced experimental conditions designed to manipulate the anxiety they experienced. Point of gaze was measured using an ASL Mobile Eye tracker and fixations including the quiet eye were determined using frame-by-frame analysis. The manipulation of anxiety resulted in significant reductions in the duration of the quiet eye period and free throw success rate, thus supporting the predictions of attentional control theory. Anxiety impaired goal-directed attentional control (quiet eye period) at the expense of stimulus-driven control (more fixations of shorter duration to various targets). The findings suggest that attentional control theory may be a useful theoretical framework for examining the relationship between anxiety and performance in visuomotor sport skills.

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Bakhtyar Tartibian, Ana Maria Botelho Teixeira and Behrouz Baghaiee

Purpose:

The purpose of the current study was to characterize the role of aerobic exercise in the gene expression of the angiotensin-converting enzyme (ACE) and the β2-adrenergic receptor (ADRB2) in untrained men.

Methods:

Twenty untrained middle-aged men were randomly assigned to exercise (Exe) and control (Con) groups. The Exe group performed aerobic exercises for eight weeks. ACE mRNA and ADRB2 mRNA were determined by PCR.

Results:

The expression of ACE in week 4 and in the Exe group decreased significantly (p < .001). ADRB2 in the Exe group, in week 4 and in week 8, was markedly higher, and blood pressure was significantly lower than in the Con group (p < .001). In the Con group ADRB2 mRNA decreased.

Conclusion:

These results suggest that moderate intensity exercise promotes the leukocyte expression of gene markers that may affect blood pressure by improving cardiovascular fitness levels in middle-aged men.

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Ashley Gibson Bowers, Christina L.L. Martin, John Miller, Brent Wolfe and Nancy Magee Speed

The purpose of the study was to examine female athletes’ perceptions of their body image as a result of comparing themselves to others. Social comparison theory (Festinger, 1954) was used as the theoretical basis for understanding the effects of body image among intercollegiate female athletes. Using a qualitative analysis, the authors individually interviewed 20 female collegiate athletes attending a Division I university and thematically coded their responses. The findings suggest that coaches and teammates significantly contribute to body image pressures in female athletes, as participants were sensitive to the comments and perceptions of these groups. Finally, athletes perceived that the external population (those outside of coaches and teammates) evaluated athletic talent based on actual body image.

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Mary O. Hearst, John R. Sirard, Leslie Lytle, Donald R. Dengel and David Berrigan

Background:

The association of physical activity (PA), measured 3 ways, and biomarkers were compared in a sample of adolescents.

Methods:

PA data were collected on 2 cohorts of adolescents (N = 700) in the Twin Cities, Minnesota, 2007–2008. PA was measured using 2 survey questions [Modified Activity Questionnaire (MAQ)], the 3-Day Physical Activity Recall (3DPAR), and accelerometers. Biomarkers included systolic (SBP) and diastolic blood pressure (DBP), lipids, percent body fat (%BF), and body mass index (BMI) percentile. Bivariate relationships among PA measures and biomarkers were examined followed by generalized estimating equations for multivariate analysis.

Results:

The 3 measures were significantly correlated with each other (r = .22–.36, P < .001). Controlling for study, puberty, age, and gender, all 3 PA measures were associated with %BF (MAQ = −1.93, P < .001; 3DPAR = −1.64, P < .001; accelerometer = −1.06, P = .001). The MAQ and accelerometers were negatively associated with BMI percentile. None of the 3 PA measures were significantly associated with SBP or lipids. The percentage of adolescents meeting the national PA recommendations varied by instrument.

Conclusions:

All 3 instruments demonstrated consistent findings when estimating associations with %BF, but were different for prevalence estimates. Researchers must carefully consider the intended use of PA data when choosing a measurement instrument.

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Olivier Caron, Thierry Gélat, Patrice Rougier and Jean-Pierre Blanchi

The center of foot pressure (CP) motions, representing the net neuromuscular control, was compared to the center of gravity (CG) motions, representing the net performance. The comparison focused on the trajectory path length parameter along the mediolateral and antero-posterior axes because these two variables depend on amplitude versus frequency relationship. This relationship was used to evaluate the CG motions based on the CP motions. Seven subjects stood still on a force plate with eyes open and eyes closed. The results showed that the ratio of (CP – CG)/CP trajectory path length was personal for each subject. These results suggest different levels of passive (ligaments, elastic properties) and active (reflex activity) stiffness. For some subjects, this ratio was significantly lower for the eyes open condition than for the eyes closed condition, indicating a decrease of the active stiffness for the eyes open condition. Therefore, a CG – CP comparative analysis appeared helpful in understanding the control of balance and necessary to quantify the subjects’ net performance.

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Patrice R. Rougier and Samir Boudrahem

Past studies have emphasized the beneficial effect of additional visual feedback (VFB) on the capacity of healthy adults to decrease the amplitudes of the center-of-pressure minus center-of-gravity (CP-CGv) movements. To better assess these capacities, 56 subjects were asked to stand still on a force platform and to use the visual information provided. Dependency coefficients, based on their capacity to lower their CP-CGv movements and therefore relax their lower limb muscles, as well as parameters aimed at characterizing their postural strategies were measured across VFB conditions including (1) CP displacements in real time (VFBCP0), (2) CP displacements with a 600-ms delay (VFBCP600), and (3) CP-CGv displacements with a 600-ms delay (VFBCP-CG600). A non-VFB condition (eyes open) was also included. Several linear correlations were used to specify the relation between subjects’ capacity to relax, compared with the VFBCP0 condition, across the three remaining conditions. The data highlight the complementary nature of the VFB conditions and establish the postural control behaviors necessary to use these VFB protocols efficiently.

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Michael L. Silk and John Amis

The analysis of televised sport production has largely ignored the conditions that frame cultural production and the ways in which broadcasts are constructed. Rather, scholarly discussions of televised sport production have been based on the text that goes to air. Given substantial realignments in political, economic, and cultural spheres brought about by the proliferation of a global media, it is argued that a textual perspective is inadequate if a thorough understanding of the complexities of televised sport production is to be attained. Rather, to appreciate the intricacies involved in cultural (re)production, scholars need to address the ways in which interactions among influential actors impact the process of reproducing sport for television. This paper investigates the conditions of production and the labor processes involved in reproducing a major sporting event. Using ethnographic data collected at the 1998 Kuala Lumpur Commonwealth Games in Malaysia, the ways in which micro and macro institutional processes interacted to frame the reproduction of the Games are assessed and discussed.

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Karrie L. Hamstra, Jeffrey M. Cherubini and C. Buz Swanik