Publication
Title
Musculoskeletal effects of 5 days of bed rest with and without locomotion replacement training
Author
Abstract
The present study evaluated the effectiveness of a short and versatile daily exercise regime, named locomotion replacement training (LRT), to maintain muscle size, isometric strength, power, and endurance capacity of the leg muscles following 5 days of head-down tilt (HDT) bed rest. 10 male subjects (age 29.4 +/- A 5.9 years; height 178.8 +/- A 3.7 cm; body mass 77.7 +/- A 4.1 kg) performed, in random order, 5 days of 6A degrees head-down tilt bed rest (BR) with no exercise (CON), or BR with daily 25 min of upright standing (STA) or LRT. Knee extensor and plantar flexor cross-sectional area (CSA) were reduced by 2-3 % following bed rest (P < 0.01) for CON and STA, yet maintained for LRT. Knee extensor isometric strength (MVC) decreased by 8 % for CON (P < 0.05), was maintained for STA, and increased with 12 % for LRT (P < 0.05). Plantar flexor MVC remained unaltered during the study. Maximum jump height declined (similar to 1.5 cm) for all conditions (P < 0.001). Neural activation and knee extensor fatigability did not change with bed rest. Bone resorption increased during BR and neither LRT nor STA was able to prevent or attenuate this increase. LRT was adequate to maintain muscle size and to even increase knee extensor MVC, but not muscle power and bone integrity, which likely requires more intense and/or longer exercise regimes. However, with only some variables showing significant changes, we conclude that 5 days of BR is an inadequate approach for countermeasure assessments.
Language
English
Source (journal)
European journal of applied physiology. - Berlin, 2000, currens
Publication
Berlin : 2015
ISSN
1439-6319 [print]
1439-6327 [online]
DOI
10.1007/S00421-014-3045-0
Volume/pages
115 :4 (2015) , p. 727-738
ISI
000351238200006
Pubmed ID
25425257
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 12.05.2015
Last edited 09.10.2023
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