Date of Award

Spring 2012

Degree Type


Degree Name

Master of Science in Kinesiology




Kathleen Martin Ginis




The purpose of this study was to examine the effects of depleted self-regulation on skillful task performance. Participants completed a baseline dart-tossing task (20 tosses), and were instructed to toss as quickly and as close to the bulls-eye as possible when a particular cue light flashed. Participants then underwent a self-regulatory depleting (experimental) or a non-depleting (control) manipulation before completing a second round of dart tossing. Measures of accuracy, reaction time, and myoelectrical activity of the biceps and triceps were collected along with self-report measures of psychological resilience and trait self-control.

As hypothesized, participants in the experimental condition had poorer mean accuracy at round two than control condition participants, as well as a significant decline in accuracy from round one to round two. These effects were moderated by trait self-control; experimental group participants with higher trait self-control were more accurate in round two than experimental group participants with lower trait self-control. Experimental group participants also demonstrated poorer consistency in accuracy compared to control group participants at round two, and a significant deterioration in consistency from round one to round two. The only significant finding regarding reaction time was that consistency improved significantly for the control group but not for the experimental group.

The results of this study provide evidence that ego depletion effects occur for skill-based physical task performance, especially in regards to accuracy. These findings provide further support for the utility of the limited strength model and suggest that self-regulatory depletion can impact performance on skill-based physical tasks.

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