title: Impact of handgrip exercise intensity on brachial artery flow-mediated dilation.
abstract: OBJECTIVE
  Previous studies that have examined the impact of exercise intensity on conduit artery endothelial function have involved large muscle group exercise which induces local and systemic effects. The aim of this study was to examine flow-mediated dilation (FMD) before and after incremental intensities of handgrip exercise (HE), to assess the role of local factors such as blood flow and shear rate on post-exercise brachial artery function.
  
  
  METHODS
  Eleven healthy men attended the laboratory on three occasions. Subjects undertook 30 min of handgrip exercise at three intensities (5, 10 or 15 % MVC). Brachial artery FMD, shear and blood flow patterns were examined before, immediately after and 60 min post exercise.
  
  
  RESULTS
  Handgrip exercise increased mean and antegrade shear rate (SR) and blood flow (BF) and reduced retrograde SR and BF (all P < 0.01). Exercise intensity was associated with a dose-dependent increase in both mean and antegrade BF and SR (interaction, P < 0.01). Post-hoc tests revealed that, whilst handgrip exercise did not immediately induce post-exercise changes, FMD was significantly higher 60 min post-exercise following the highest exercise intensity (5.9 ± 2.8-10.4 ± 5.8 %, P = 0.01).
  
  
  CONCLUSIONS
  Handgrip exercise leads to intensity-and time-dependent changes in conduit artery function, possibly mediated by local increases in shear, with improvement in function evident at 1 h post-exercise when performed at a higher intensity.
authors: School of Sports Science, Exercise and Health, The University of Western Australia, Crawley, WA, Australia, ceri.atkinson@research.uwa.edu.au.
authors: Ceri L
authors: CL
authors: Atkinson
authors: Howard H
authors: HH
authors: Carter
authors: Ellen A
authors: EA
authors: Dawson
authors: Louise H
authors: LH
authors: Naylor
authors: Dick H J
authors: DH
authors: Thijssen
authors: Daniel J
authors: DJ
authors: Green
mesh_terms: D000328:Adult; D062186:Arterial Pressure / Q000502:physiology; D001916:Brachial Artery / Q000033:anatomy & histology / Q000502:physiology*; D004730:Endothelium, Vascular / Q000502:physiology; D018737:Hand Strength / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D016014:Linear Models; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D012039:Regional Blood Flow / Q000502:physiology; D055070:Resistance Training; D014664:Vasodilation / Q000502:physiology*; D055815:Young Adult
chemical_list: D017382:Reactive Oxygen Species