The Effects of Caffeine on Arousal, Response Time, Accuracy, and Performance in Division I Collegiate Fencers.

Doyle, TP, Lutz, RS, Pellegrino, JK, Sanders, DJ, and Arent, SM. The effects of caffeine on arousal, response time, accuracy, and performance in Division I collegiate fencers. J Strength Cond Res 30(11): 3228-3235, 2016-Caffeine has displayed ergogenic effects on aerobic performance.

Taking aim at the Müller-Lyer goalkeeper illusion: an illusion bias in action that originates from the target not being optically specified.

Van der Kamp and Masters (2008) reported that goalkeeper postures that mimic the Müller-Lyer (1889) illusion affect the location of handball penalty throws. In four experiments, we aimed to verify that the effects on throwing are consistent with an illusory bias (Experiments 1 and 2), and to examine how these observations can be understood in the context of Milner and Goodale's (1995, 2008) two-visual systems model (Experiments 3 and 4). Experiments 1 and 2 confirmed that the goalkeeper Müller-Lyer posture may indeed induce an illusory bias in throwing, implying that allocentric information is used in far-aiming action tasks.

Cross-lagged relationships among leisure-time exercise and perceived stress in blue-collar workers.

Blue-collar workers (N = 203) from a large food-processing plant in the southwestern U.S. completed measures of perceived stress and leisure-time exercise at an initial test session in addition to a 2-month follow-up session.

Examination of the hierarchical self-esteem model in adults with physical disability.

The primary purpose of this research was to examine the validity of the hierarchical physical self-perceptions model developed by Fox and Corbin (1989) within a population of physically disabled individuals. The secondary purpose was to compare the physical self-perceptions of those who were physically active and physically inactive. 97 adults with physical disabilities completed a self-esteem scale and the Physical Self-perception Profile, Japanese short version to assess General Physical Self-worth and its subdomains of Perceived Sports Competence, Physical Condition, Attractive Body, and Physical Strength.

Perceived stress and health complaints: an examination of the moderating roles of personality and physical activity.

275 undergraduate university students were asked to complete a battery concerning their health complaints, perceived stress, strenuous physical activity, and personality ("Big Five" traits). An hierarchical regression showed that Stress and Strenuous Physical Activity Participation, but not Personality, predicted the Number of Health Complaints in this sample. Also, there was a significant interaction for Stress by Strenuous Activity indicating individuals who did not frequently engage in strenuous leisure-time physical activity reported more health complaints than those who did.

Social support and social norms: do both contribute to predicting leisure-time exercise?

Objective: To clarify the contribution of social support and social norms to exercise behavior.

Methods: A sample of 363 college students completed a questionnaire that assessed social support and social negativity from friends, descriptive and injunctive social norms related to friends, perceived behavioral control, attitude, intention, and leisure-time exercise.

Results: Esteem social support was the strongest predictor of total and strenuous leisure-time exercise (P < .

Covert muscle excitation is outflow from the central generation of motor imagery.

Two studies were conducted in an attempt to examine inflow and outflow processing by examining covert muscle excitation during motor imagery (MI) and its correlation with motor task performance. Examining 80 novice dart throwers in Experiment 1, MI produced greater levels of covert excitation at the dominant biceps in comparison to control imagery (CI). In addition, covert excitation correlated significantly with imagery ability and imagery vividness.

Should the threshold limit value for power frequency (60 Hz) magnetic fields be changed? Perceptions among scientists and other risk experts.

Over the past few years several studies have raised questions about childhood cancer and exposure to electric and magnetic fields (EMFs). Reports by the National Academy of Sciences and the National Cancer Institute concluded that there is no clear, convincing evidence that exposure to electric power lines and electric power appliances is a threat to human health, whereas the National Institute of Environmental Health Sciences concluded that there is weak evidence that EMF exposure may be a leukemia hazard. Based on the conflicting agency reports on EMF, what do experts in the field of bioelectromagnetics believe regarding the effectiveness of the American Conference of Governmental Industrial Hygienists (ACGIH) guidelines? Surveys were sent to 163 participants at the 1997 annual Department of Energy Contractors meeting on Electric and Magnetic Fields.

Attitudes about electric and magnetic fields: do scientists and other risk experts perceive risk similarly?

Wherever there is electric power, 60-hertz (60-Hz) electric and magnetic fields (EMFs) are produced. Recently, conflicting reports have been published by government agencies about adverse health effects linked to EMFs. This paper seeks to identify the demographic and job-related factors that may explain differences among experts' perception of risk attributable to EMFs.

Clarifying the contribution of subjective norm to predicting leisure-time exercise.

Objective: To clarify the contribution of subjective norm to exercise intention and behavior by considering the influence of descriptive as well as injunctive social norms related to family and friends.

Methods: A sample of 530 college students completed a questionnaire that assessed descriptive and injunctive social norms related to family and to friends, perceived behavioral control, attitude, intention, and leisure-time exercise.

Results: Friend descriptive social norm was a significant predictor of both intention (p<.

Affect and Cognitive Performance in High School Wrestlers Undergoing Rapid Weight Loss.

Recent research has demonstrated transient affective changes and impairment of short-term memory in college wrestlers as a result of rapid weight loss (RWL) of at least 5% body weight prior to competition. This study examined the effects of RWL on cognition and affect in high school wrestlers. Wrestlers were considered to be engaging in RWL if they were losing over 5% of body weight (n = 14).