title: Effects of self-regulatory strength depletion on muscular performance and EMG activation.
abstract: The purpose of the present study was to examine the effects of a self-regulatory strength depletion manipulation on performance of a physical endurance (isometric handgrip) task. In addition, the effect of depletion on EMG activity in the working forearm muscles during the endurance task was explored. Sedentary undergraduates (N=49) were randomly assigned to either a cognitive depletion condition (modified Stroop task) or a control (color word) group and completed two maximal isometric exercise endurance trials separated by the cognitive task. Participants in the depletion group showed significant (p<.05) degradations in performance and exhibited higher EMG activation on the second endurance trial (p<.05) compared to controls. Results are consistent with the limited strength model of self-regulation and are interpreted in light of the central fatigue hypothesis.
authors.affiliation: Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Steven R
authors.initials: SR
authors.lastname: Bray
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Martin Ginis
authors.forename: Audrey L
authors.initials: AL
authors.lastname: Hicks
authors.forename: Jennifer
authors.initials: J
authors.lastname: Woodgate
mesh_terms: D000328:Adult; D000339:Affect; D004576:Electromyography; D015444:Exercise / Q000502:physiology; D005260:Female; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology*