Effects of posture on cardiovascular responses to lower body positive pressure at rest and during dynamic exercise

Takeshi Nishiyasu, Kei Nagashima, Ethan R. Nadel, Gary W. Mack

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

We tested the hypothesis that cardiovascular responses to lower body positive pressure (LBPP) would be dependent on the posture of the subject and also on the background condition (rest or exercise). We measured heart rate (HR), mean arterial blood pressure (MAP), and cardiac Stroke volume in eight subjects at rest and during cycle ergometer exercise (76 ± 3 W) with and without LBPP (25, 50, and 75 mmHg) in the supine and upright positions. At rest, the increase in MAP was proportional to the increase in LBPP and was greater in the supine (6 ± 2, 15 ± 3, and 26 ± 3 mmHg) than in the upright (2 ± 3, 9 ± 3, and 17 ± 3 mmHg) position. During dynamic exercise, the increases in MAP evoked by 25, 50, and 75 mmHg LBPP were greater in the supine (13 ± 2, 28 ± 3, and 40 ± 3 mmHg) than in the upright (7 ± 3, 12 ± 3, and 25 ± 3 mmHg) position. We conclude that the systemic pressure response to LBPP is clearly dependent on the body position, with the larger pressure responses being associated with the supine position both at rest and during dynamic leg exercise.

Original languageEnglish
Pages (from-to)160-167
Number of pages8
JournalJournal of Applied Physiology
Volume85
Issue number1
DOIs
Publication statusPublished - 1998 Jul

Keywords

  • Exercise
  • Lower body positive pressure
  • Mean arterial blood pressure
  • Muscle mechanoreflex
  • Muscle metaboreflex
  • Upright

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Effects of posture on cardiovascular responses to lower body positive pressure at rest and during dynamic exercise'. Together they form a unique fingerprint.

  • Cite this