title: The use of an isometric handgrip test to show autonomic damage in people with diabetes.
abstract: BACKGROUND
  Vascular endothelial and autonomic damage are hallmarks of type 1 and type 2 diabetes. However, while much has been published on impairment of the autonomic nervous system, much less has been published on the interrelationship between autonomic damage and exercise.
  
  
  METHODS
  The present investigation examined the change in heart rate, blood pressure, skin and limb blood flow, and sweat during non-fatiguing (10% and 25% maximum strength [maximal voluntary contraction (MVC)]) and a fatiguing isometric contraction (40% MVC) in people with type 2 diabetes compared to younger and older controls to see if a simple handgrip test could show the extent of autonomic damage in people with diabetes. Fifteen younger subjects (30.6 +/- 8.6 years), 15 older subjects (65.8 +/- 8.8 years), and 15 subjects with diabetes (63.4 +/- 14.4 years) whose average percentage body fat was 40.1 +/- 12.9%, 36.1 +/- 9.3%, and 39.6 +/- 15.5%, respectively, participated in these studies. Whole forearm blood flow, skin blood flow, and sweat on the forearm, chest, and forehead were measured at rest and during and after a contraction at 10% MVC, 25% MVC, and 40% MVC.
  
  
  RESULTS
  Blood flows and sweat rates were greatest in younger subjects, significantly less in older subjects, and even significantly less in subjects with diabetes (P < 0.05). The heart rate response was unaltered during contractions at 10% and 25% MVC and less in diabetes than in the other two groups with 40% MVC. Strength was about half in the diabetes group than with the other two groups, but endurance was similar.
  
  
  CONCLUSIONS
  Diabetes is associated with a reduction in handgrip strength and significantly impaired autonomic function during and after isometric exercise.
authors.affiliation: Department of Physical Therapy, Loma Linda University, Loma Linda, California 92350, USA. jpetrofsky@llu.edu
authors.forename: Jerrold
authors.initials: J
authors.lastname: Petrofsky
authors.forename: Michelle
authors.initials: M
authors.lastname: Prowse
authors.forename: Wilton
authors.initials: W
authors.lastname: Remigio
authors.forename: Chinna
authors.initials: C
authors.lastname: Raju
authors.forename: Samuel
authors.initials: S
authors.lastname: Salcedo
authors.forename: Melissa
authors.initials: M
authors.lastname: Sirichotiratana
authors.forename: Piyush
authors.initials: P
authors.lastname: Madani
authors.forename: Raja Ram
authors.initials: RR
authors.lastname: Chamala
authors.forename: Eryn
authors.initials: E
authors.lastname: Puckett
authors.forename: May
authors.initials: M
authors.lastname: Wong
authors.forename: Matthew
authors.initials: M
authors.lastname: Fajita
authors.forename: Ramneek
authors.initials: R
authors.lastname: Kaur
authors.forename: Staci
authors.initials: S
authors.lastname: Moore
authors.forename: Andrea
authors.initials: A
authors.lastname: Pereira
authors.forename: Swapna
authors.initials: S
authors.lastname: Katikaneni
authors.forename: Krishna
authors.initials: K
authors.lastname: Regula
authors.forename: Prasanth
authors.initials: P
authors.lastname: Elavarthy
authors.forename: Ujjwal
authors.initials: U
authors.lastname: Kumar
authors.forename: Linga
authors.initials: L
authors.lastname: Raju
authors.forename: Ashita
authors.initials: A
authors.lastname: Gadagoju
mesh_terms: D000328:Adult; D000368:Aged; D001342:Autonomic Nervous System Diseases / Q000175:diagnosis* / Q000503:physiopathology; D001783:Blood Flow Velocity; D001794:Blood Pressure; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000175:diagnosis* / Q000503:physiopathology; D015444:Exercise; D005542:Forearm / Q000098:blood supply; D018737:Hand Strength / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D007537:Isometric Contraction; D008875:Middle Aged; D009119:Muscle Contraction; D012016:Reference Values; D012867:Skin / Q000098:blood supply; D055815:Young Adult