{"id":{"repo_id":"nmu","oai_identifier":"oai:commons.nmu.edu:theses-1911"},"canonical_url":"https://search.dev.ndltd.org/etd/nmu/oai:commons.nmu.edu:theses-1911","repository":{"repo_id":"nmu","name":"Northern Michigan University","base_url":"https://commons.nmu.edu/do/oai/"},"display":{"title":"Transcranial Direct Current Stimulation of the Dorsolateral Prefrontal Cortex Does Not Improve Handgrip Time-to-Failure or Alter Central or Peripheral Hemodynamics","abstract":"<p>Age-related deviations to the neuromuscular system negatively impact motor function and performance. Transcranial direct current stimulation (tDCS) has been linked to improvements in the neuromuscular system. The purpose of this study was to determine if tDCS delivered to the dorsolateral prefrontal cortex (DLPFC) would improve handgrip time-to-failure in adults 60 years old and older. Twenty-five participants completed five maximal voluntary contractions, followed by 20-minutes of a-tDCS or SHAM conditions. Next, participants completed a handgrip time-to-failure task by maximally squeezing an electronic handgrip dynamometer until they could no longer maintain 50% of their maximal voluntary contraction. Pairwise t-test revealed a non-significant difference between tDCS and SHAM conditions on handgrip time-to- failure t(24 ) = 0.254, p = 0.401. Separate 2 x 5 ANOVA’s revealed no main effect of condition on changes in baseline HbO, HbR, and HbT for DLPFC and muscle hemodynamics (all <em>p </em>> 0.05). A linear mixed-effects model revealed no significant main effect of condition on recovery MVC (<em>p </em>> 0.05). This study provides evidence tDCS does not improve HGTTF in older adults, adding contrastingevidence regarding the effects of an acute session of tDCS. Further research is needed to confirm the ergogenic effects of acute tDCS.</p>","abstract_html":"&lt;p&gt;Age-related deviations to the neuromuscular system negatively impact motor function and performance. Transcranial direct current stimulation (tDCS) has been linked to improvements in the neuromuscular system. The purpose of this study was to determine if tDCS delivered to the dorsolateral prefrontal cortex (DLPFC) would improve handgrip time-to-failure in adults 60 years old and older. Twenty-five participants completed five maximal voluntary contractions, followed by 20-minutes of a-tDCS or SHAM conditions. Next, participants completed a handgrip time-to-failure task by maximally squeezing an electronic handgrip dynamometer until they could no longer maintain 50% of their maximal voluntary contraction. Pairwise t-test revealed a non-significant difference between tDCS and SHAM conditions on handgrip time-to- failure t(24 ) = 0.254, p = 0.401. Separate 2 x 5 ANOVA’s revealed no main effect of condition on changes in baseline HbO, HbR, and HbT for DLPFC and muscle hemodynamics (all &lt;em&gt;p &lt;/em&gt;&gt; 0.05). A linear mixed-effects model revealed no significant main effect of condition on recovery MVC (&lt;em&gt;p &lt;/em&gt;&gt; 0.05). This study provides evidence tDCS does not improve HGTTF in older adults, adding contrastingevidence regarding the effects of an acute session of tDCS. Further research is needed to confirm the ergogenic effects of acute tDCS.&lt;/p&gt;","abstract_has_math":false,"creators":["Qadumi, Yousef"],"institution":null,"degree_name":"Master of Science","degree_level":"Thesis","degree_discipline":"Health and Human Performance","degree_department":null,"school":null,"contributors":["Matthew Kilgas"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024-07-01T07:00:00Z","date_published":"2024-07-01T07:00:00Z","updated_at":"2026-07-24T03:24:36Z","subjects":["Near-Infrared Spectroscopy","Aging","Maximal Voluntary Contraction","Performance","Fatuige","Other Public Health"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://commons.nmu.edu/theses/855","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Matthew Kilgas"]},{"key":"dc:creator","label":"Author","values":["Qadumi, Yousef"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2024-07-11T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Health and Human Performance"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Near-Infrared Spectroscopy","Aging","Maximal Voluntary Contraction","Performance","Fatuige","Other Public Health"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://commons.nmu.edu/theses/855"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["<p>Age-related deviations to the neuromuscular system negatively impact motor function and performance. Transcranial direct current stimulation (tDCS) has been linked to improvements in the neuromuscular system. The purpose of this study was to determine if tDCS delivered to the dorsolateral prefrontal cortex (DLPFC) would improve handgrip time-to-failure in adults 60 years old and older. Twenty-five participants completed five maximal voluntary contractions, followed by 20-minutes of a-tDCS or SHAM conditions. Next, participants completed a handgrip time-to-failure task by maximally squeezing an electronic handgrip dynamometer until they could no longer maintain 50% of their maximal voluntary contraction. Pairwise t-test revealed a non-significant difference between tDCS and SHAM conditions on handgrip time-to- failure t(24 ) = 0.254, p = 0.401. Separate 2 x 5 ANOVA’s revealed no main effect of condition on changes in baseline HbO, HbR, and HbT for DLPFC and muscle hemodynamics (all <em>p </em>> 0.05). A linear mixed-effects model revealed no significant main effect of condition on recovery MVC (<em>p </em>> 0.05). This study provides evidence tDCS does not improve HGTTF in older adults, adding contrastingevidence regarding the effects of an acute session of tDCS. Further research is needed to confirm the ergogenic effects of acute tDCS.</p>"]},{"key":"dc:title","label":"Title","values":["Transcranial Direct Current Stimulation of the Dorsolateral Prefrontal Cortex Does Not Improve Handgrip Time-to-Failure or Alter Central or Peripheral Hemodynamics"]}]}],"canonical_facts":{"dc:contributor":["Matthew Kilgas"],"dc:creator":["Qadumi, Yousef"],"dc:date.available":["2024-07-11T07:00:00Z"],"dc:description.abstract":["<p>Age-related deviations to the neuromuscular system negatively impact motor function and performance. Transcranial direct current stimulation (tDCS) has been linked to improvements in the neuromuscular system. The purpose of this study was to determine if tDCS delivered to the dorsolateral prefrontal cortex (DLPFC) would improve handgrip time-to-failure in adults 60 years old and older. Twenty-five participants completed five maximal voluntary contractions, followed by 20-minutes of a-tDCS or SHAM conditions. Next, participants completed a handgrip time-to-failure task by maximally squeezing an electronic handgrip dynamometer until they could no longer maintain 50% of their maximal voluntary contraction. Pairwise t-test revealed a non-significant difference between tDCS and SHAM conditions on handgrip time-to- failure t(24 ) = 0.254, p = 0.401. Separate 2 x 5 ANOVA’s revealed no main effect of condition on changes in baseline HbO, HbR, and HbT for DLPFC and muscle hemodynamics (all <em>p </em>> 0.05). A linear mixed-effects model revealed no significant main effect of condition on recovery MVC (<em>p </em>> 0.05). This study provides evidence tDCS does not improve HGTTF in older adults, adding contrastingevidence regarding the effects of an acute session of tDCS. Further research is needed to confirm the ergogenic effects of acute tDCS.</p>"],"dc:identifier":["https://commons.nmu.edu/theses/855"],"dc:subject":["Near-Infrared Spectroscopy","Aging","Maximal Voluntary Contraction","Performance","Fatuige","Other Public Health"],"dc:title":["Transcranial Direct Current Stimulation of the Dorsolateral Prefrontal Cortex Does Not Improve Handgrip Time-to-Failure or Alter Central or Peripheral Hemodynamics"],"thesis:degree_discipline":["Health and Human Performance"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Master of Science"]},"updated_at":"2026-07-24T03:24:36Z"}