title: Relationship between reduced lower abdominal blood flows and heart rate in recovery following cycling exercise.
abstract: OBJECTIVE
  To examine the blood flow (BF) response in the lower abdomen (LAB) in recovery following upright cycling exercise at three levels of relative maximum pulmonary oxygen consumption (VO(2max)) and the relationship of BF(LAB) to heart rate (HR) and target intensity.
  
  
  METHODS
  For 11 healthy subjects, BF (Doppler ultrasound) in the upper abdominal aorta (Ao) above the coeliac trunk and in the right femoral artery (RFA) was measured repeatedly for 720 s after the end of cycling exercises at target intensities of 30%, 50% and 85% VO(2max), respectively. Blood flow in the lower abdomen (BF(LAB)) can be measured by subtracting bilateral BF(FAs) (≈twofolds of BF(RFA)) from BF(Ao). Change in BF(LAB) (or BF(LAB) volume) at any point was evaluated by difference between change in BF(Ao) and in BF(FAs). Heart rate and blood pressure were also measured.
  
  
  RESULTS
  At 85% VO(2max), significant reduction in BF(LAB) by approx. 89% was shown at 90 s and remained until 360 s. At 50% VO(2max), reduction in BF(LAB) by approx. 33% was found at 90 s although it returned to pre-exercise value at 120 s. On the contrary at 30% VO(2max), BF(LAB) showed a light increase (<20%) below 70 bpm of HR. There was a close negative relationship (P < 0.05) between change in BF(LAB) and recovery HR, as well as between change in BF(LAB) volume and both recovery HR and % VO(2max).
  
  
  CONCLUSIONS
  This study suggests that the lower abdominal BF in recovery may be influenced by sympathetic-vagus control, and dynamics of BF(LAB) may be closely related to the level of relative exercise intensities.
authors.affiliation: Department of Sports Medicine for Health Promotion, Tokyo Medical University, Japan. DENTACMAC@aol.com
authors.forename: T
authors.initials: T
authors.lastname: Osada
authors.forename: H
authors.initials: H
authors.lastname: Iwane
authors.forename: T
authors.initials: T
authors.lastname: Katsumura
authors.forename: N
authors.initials: N
authors.lastname: Murase
authors.forename: H
authors.initials: H
authors.lastname: Higuchi
authors.forename: A
authors.initials: A
authors.lastname: Sakamoto
authors.forename: T
authors.initials: T
authors.lastname: Hamaoka
authors.forename: T
authors.initials: T
authors.lastname: Shimomitsu
mesh_terms: D000005:Abdomen / Q000098:blood supply*; D000328:Adult; D000704:Analysis of Variance; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging / Q000502:physiology*; D001642:Bicycling; D001794:Blood Pressure; D015444:Exercise; D005263:Femoral Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D016014:Linear Models; D008297:Male; D009119:Muscle Contraction; D010101:Oxygen Consumption; D012123:Pulmonary Ventilation; D020127:Recovery of Function; D012039:Regional Blood Flow; D013152:Splanchnic Circulation; D013997:Time Factors; D018608:Ultrasonography, Doppler; D055815:Young Adult