title: Heart rate recovery after exercise is related to the insulin resistance syndrome and heart rate variability in elderly men.
abstract: OBJECTIVE
  We investigated the associations between heart rate recovery after exercise (as a suggested measure of vagal activity), heart rate variability, and measurements of the insulin resistance syndrome.
  
  
  METHODS
  Seventy men aged 70 years were examined with a symptom-limited bicycle exercise test, a 24-hour heart rate variability test, and different measurements of different components of the insulin resistance syndrome.
  
  
  RESULTS
  Heart rate recovery after exercise (mean +/- SD 20 +/- 9 beats during the first minute) was related to both the SD of the R-R interval and the low frequency power at the heart rate variability analyses (r = 0.39, P <.002 for both). Furthermore, heart rate recovery after exercise was related to insulin sensitivity at the hyperinsulinemic eugleucemic clamp (r = 0.28, P <.03), and to high-density lipoprotein cholesterol and exercise capacity, and inversely to obesity and insulin and glucose levels 2 hours after an oral glucose load (P <.05 for all). Heart rate recovery after exercise was not related to left ventricular mass measured by means of echocardiography or to the number of ventricular premature complexes at a 24-hour Holter recording.
  
  
  CONCLUSIONS
  Heart rate recovery 1 minute after exercise was related to measurements of 24-hour heart rate variability. Furthermore, heart rate recovery after exercise was related to several of the major components of the insulin resistance syndrome, thereby establishing a link between this syndrome and cardiac autonomic nervous activity.
mesh_terms: D000367:Age Factors; D000368:Aged; D001341:Autonomic Nervous System / Q000503:physiopathology*; D015716:Electrocardiography, Ambulatory; D005080:Exercise Test; D006339:Heart Rate / Q000502:physiology*; D006352:Heart Ventricles / Q000033:anatomy & histology; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D013577:Syndrome; D013997:Time Factors; D016277:Ventricular Function, Left / Q000502:physiology; D018879:Ventricular Premature Complexes / Q000503:physiopathology*