HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 104/4/938    most recent 01021.2007v1 Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Arbeille, P. Articles by Hughson, R. L. PubMed PubMed Citation Articles by Arbeille, P. Articles by Hughson, R. L.

WISE-2005: tibial and gastrocnemius vein and calf tissue response to LBNP after a 60-day bed rest with and without countermeasures

¹Unité de Médecine et Physiologie Spatiales (UMPS), Centres Hospitaliers Universitaires Trousseau, Tours, France; ²Faculty of Applied Health Sciences, University of Waterloo, Waterloo, Ontario; and ³School of Kinesiology, University of Western Ontario, London, Ontario, Canada

Submitted 26 September 2007 ; accepted in final form 11 January 2008

The objective of this study was to quantify by echography the changes in the intramuscular [gastrocnemius (Gast)] and nonintramuscular [posterior tibial (Tib)] calf veins cross-sectional area (CSA) and the superficial tissue thickness (STth) in response to lower body negative pressure (LBNP) after 60-day head-down bed rest (HDBR). Twenty-four healthy women (25–40 yr) were divided into three groups: control (Con), treadmill-LBNP and flywheel (Ex-Lb), nutrition (Nut; protein supplement). All underwent a LBNP (0 and –45 mmHg) before and on day 55 of HDBR. Subjects were identified as finisher (F) or nonfinisher (NF) of a 10-min tilt test after 60 days of HDBR. There were no differences in resting CSA of the Tib and Gast veins on HDBR day 55 compared with pre-HDBR for the Ex-Lb, Con and Nut, or the F groups; however, for NF both the Tib and Gast vein CSA at rest were significantly smaller after HDBR. At –45 mmHg LBNP, Tib and Gast CSAs were not significantly different from before HDBR in all groups (Ex-Lb, Con, Nut, F, NF). However, percent change in CSA of both veins from rest to –45 mmHg LBNP was significantly greater in the Con and Nut groups compared with Ex-Lb, and also NF compared with F. Similarly, the percent increase in STth on going from rest to –45 mmHg was higher after HDBR in the Con and Nut groups compared with Ex-Lb, as well as NF compared with F. These results showed that the Ex-Lb countermeasure minimized the bed rest effect on leg vein capacitance (CSA percent change) and STth increase during LBNP, whereas Nut had no effect and that higher leg vein and superficial tissue capacitance were associated with reduced orthostatic tolerance.

leg vein; lower body negative pressure; head-down bed rest; echography; Women International Space Simulation for Exploration 2005