title: Attenuated heart rate recovery following exercise testing in overweight young men with untreated obstructive sleep apnea.
abstract: OBJECTIVE
  To evaluate whether cardiovascular responses to maximal exercise testing and recovery are altered with obstructive sleep apnea (OSA) in overweight young adult men.
  
  
  METHODS
  Three sedentary subject groups were recruited: Overweight with OSA (OSA), overweight without OSA (No-OSA), and normal weight without OSA (Control). Presence of OSA was screened via portable diagnostic device. Body composition was measured with dual-energy X-ray absorptiometry. Subjects performed maximal ramping exercise testing (RXT) on a cycle ergometer with 5 minutes of active recovery. Exercise measurements included heart rate (HR), blood pressure (BP), respiratory exchange ratio (RER), and oxygen consumption (VO2). Recovery HR was converted to a HR difference (HR(diff)) calculation (HR(peak) - HR(each minute recovery)), and BP was converted to a recovery ratio for each minute.
  
  
  METHODS
  The study was carried out on the campus of Virginia Tech, Department of Human Nutrition, Foods, and Exercise, Blacksburg, Virginia.
  
  
  METHODS
  14 OSA, 16 No-OSA, and 14 Control volunteers.
  
  
  METHODS
  N/A.
  
  
  RESULTS
  In OSA subjects, HR recovery was significantly attenuated compared to the No-OSA and Control groups throughout recovery (P = 0.009). No differences were noted in the HR or BP response to exercise in any group. The VO2, adjusted for fat-free soft tissue mass, did not differ between groups.
  
  
  CONCLUSIONS
  We found that OSA elicits alterations in the cardiovascular response post exercise, reflected by an attenuated HR recovery. This may indicate an imbalance in the autonomic regulation of HR. Exercise tests may provide utility in risk stratification for those at risk for OSA.
authors.affiliation: Laboratory for Health and Exercise Science, Department of Human Nutrition, Foods and Exercise, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
authors.forename: Trent A
authors.initials: TA
authors.lastname: Hargens
authors.forename: Stephen G
authors.initials: SG
authors.lastname: Guill
authors.forename: Donald
authors.initials: D
authors.lastname: Zedalis
authors.forename: John M
authors.initials: JM
authors.lastname: Gregg
authors.forename: Sharon M
authors.initials: SM
authors.lastname: Nickols-Richardson
authors.forename: William G
authors.initials: WG
authors.lastname: Herbert
mesh_terms: D000328:Adult; D001341:Autonomic Nervous System / Q000503:physiopathology; D001794:Blood Pressure; D015992:Body Mass Index; D002302:Cardiac Output; D005080:Exercise Test; D006339:Heart Rate; D006801:Humans; D008297:Male; D050177:Overweight / Q000150:complications / Q000503:physiopathology*; D012016:Reference Values; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000503:physiopathology*; D013318:Stroke Volume