title: Cardiovascular endurance and heart rate variability in adolescents with type 1 or type 2 diabetes.
abstract: BACKGROUND
  Incidence rates of both type 1 and type 2 diabetes mellitus (DM) are increasing in youth and may eventually contribute to premature heart disease in early adulthood. This investigation explored the influence of type of diabetes, gender, body mass index (BMI), metabolic control (HbA1c), exercise beliefs and physical activity on cardiovascular endurance (CE), and heart rate variability (HRV). Differences in exercise beliefs, physical activity, HRV, and CE in youth with type 1 versus type 2 DM were determined.
  
  
  METHODS
  Adolescents with type 1 DM (n = 105) or with type 2 DM (n = 27) completed the Exercise Belief Instrument and the Physical Activity Recall. Twenty-four HRV measures were obtained via Holter monitoring and analyzed using SpaceLabs Vision Premier software system. The McMaster cycle test was used to measure CE (V0(2peak)).
  
  
  RESULTS
  Regardless of the type of DM, females and those with higher BMI, poorer metabolic control, and lower amounts of physical activity tended to have lower levels of CE. Exercise beliefs consistently predicted both frequency and time domain HRV measures. Measures of exercise beliefs, self-reported physical activity, CE (V0(2peak)), and HRV were significantly lower in adolescents with type 2 DM in comparison to those with type 1 DM.
  
  
  CONCLUSIONS
  Early findings of poor physical fitness, lower HRV, fewer positive beliefs about exercise, and less active lifestyles highlight the importance of developing culturally sensitive interventions for assisting youth to make lifelong changes in their physical activity routines. Females, those with poorer metabolic control, and minority youth with type 2 DM may be particularly vulnerable to later cardiovascular disease.
authors.affiliation: Department of Maternal and Child Nursing, College of Nursing, University of Illinois at Chicago, 60612-7350, USA. melissaf@uic.edu
authors.forename: Melissa Spezia
authors.initials: MS
authors.lastname: Faulkner
authors.forename: Laurie
authors.initials: L
authors.lastname: Quinn
authors.forename: James H
authors.initials: JH
authors.lastname: Rimmer
authors.forename: Barry H
authors.initials: BH
authors.lastname: Rich
mesh_terms: D000293:Adolescent; D001294:Attitude to Health; D002319:Cardiovascular System / Q000503:physiopathology*; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism / Q000503:physiopathology* / Q000517:prevention & control / Q000523:psychology*; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism / Q000503:physiopathology* / Q000517:prevention & control / Q000523:psychology*; D015716:Electrocardiography, Ambulatory; D005080:Exercise Test; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D015438:Health Behavior; D006306:Health Surveys; D006339:Heart Rate; D006801:Humans; D008297:Male; D015146:Midwestern United States; D008960:Models, Psychological; D010807:Physical Endurance; D000297:Psychology, Adolescent; D012307:Risk Factors; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires
chemical_list: D006442:Glycated Hemoglobin