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Kevin R. Short, Melinda Sheffield-Moore and David L. Costill

This investigation was undertaken to determine whether consuming several small feedings of preexercise carbohydrate (CHO), rather than a single bolus, would affect blood glucose and insulin responses during rest and exercise. Eight trained cyclists ingested 22.5,45, or 75 total g maltodextrin and dextrose dissolved in 473 ml of water or an equal volume of placebo (PL). Drinks were divided into four portions and consumed at 15-min intervals in the hour before a 120-min ride at 66% VO2max. Serum glucose values were elevated by the CHO feedings at rest and fell significantly below baseline and PL at 15 min of exercise. However, glucose concentrations were similar in each of the CHO trials. Insulin concentrations also increased rapidly during rest, then fell sharply at the onset of exercise. The findings demonstrate that CHO consumed within an hour before exercise, even when taken in several small feedings, can produce transient hypoglycemia near the onset of exercise. Additionally, the magnitude of the response appears to be unrelated to either the amount of CHO ingested or the insulin response.

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Mark S. Allen, Marc V. Jones and David Sheffield

The purpose of this study was to explore the influence of postcompetition positive reflection on attributions, emotions, and self-efficacy. Following a golf putting competition, participants (n = 80) were randomly assigned to either an experimental or control group. In the experimental group participants completed a modified version of the performance evaluation sheet (Holder, 1997). In the control group participants completed the concentration grid exercise (Harris & Harris, 1984). All participants subsequently completed measures of causal attribution, emotion, and self-efficacy. Findings showed that participants in the experimental condition made attributions that were significantly more internal and personally controllable than participants in the control group irrespective of competition outcome. No differences were observed between groups on measures of emotion and self-efficacy. This study suggests that reflecting back on positive elements of performance is a useful strategy for developing desirable attributions in sport performers, but may not necessarily promote self-efficacy or positive emotions.

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Martin J. Turner, Marc V. Jones, David Sheffield, Matthew J. Slater, Jamie B. Barker and James J. Bell

This study assessed whether cardiovascular (CV) reactivity patterns indexing challenge and threat states predicted batting performance in elite male county (N = 12) and national (N = 30) academy cricketers. Participants completed a batting test under pressure, before which CV reactivity was recorded in response to ego-threatening audio instructions. Self-reported self-efficacy, control, achievement goals, and emotions were also assessed. Challenge CV reactivity predicted superior performance in the Batting Test, compared with threat CV reactivity. The relationships between self-report measures and CV reactivity, and self-report measures and performance were inconsistent. A small subsample of participants who exhibited threat CV reactivity, but performed well, reported greater self-efficacy than participants who exhibited threat CV reactivity, but performed poorly. Also a small subsample of participants who exhibited challenge reactivity, but performed poorly, had higher avoidance goals than participants with challenge reactivity who performed well. The mechanisms for the observed relationship between CV reactivity and performance are discussed alongside implications for future research and applied practice.