Faculty Collaboration Database

Comparison of a space shuttle flight (STS-78) and bed rest on human muscle function. J Appl Physiol (1985) 2001 Jul;91(1):57-64

Date

06/16/2001

Pubmed ID

11408413

DOI

10.1152/jappl.2001.91.1.57

Scopus ID

2-s2.0-0034971330 (requires institutional sign-in at Scopus site)   82 Citations

Abstract

The purpose of this investigation was to assess muscle fiber size, composition, and in vivo contractile characteristics of the calf muscle of four male crew members during a 17-day spaceflight (SF; Life and Microgravity Sciences Spacelab Shuttle Transport System-78 mission) and eight men during a 17-day bed rest (BR). The protocols and timelines of these two investigations were identical, therefore allowing for direct comparisons between SF and the BR. The subjects' age, height, and weight were 43 +/- 2 yr, 183 +/- 4 cm, and 86 +/- 3 kg for SF and 43 +/- 2 yr, 182 +/- 3 cm, and 82 +/- 4 kg for BR, respectively. Calf muscle strength was examined before SF and BR; on days 2, 8, and 12 during SF and BR; and on days 2 and 8 of recovery. Muscle biopsies were obtained before and within 3 h after SF (gastrocnemius and soleus) and BR (soleus) before reloading. Maximal isometric calf strength and the force-velocity characteristics were unchanged with SF or BR. Additionally, neither SF nor BR had any effect on fiber composition or fiber size of the calf muscles studied. In summary, no changes in calf muscle strength and morphology were observed after the 17-day SF and BR. Because muscle strength is lost during unloading, both during spaceflight and on the ground, these data suggest that the testing sequence employed during the SF and BR may have served as a resistance training countermeasure to attenuate whole muscle strength loss.

Author List

Trappe SW, Trappe TA, Lee GA, Widrick JJ, Costill DL, Fitts RH

Author

Robert Fitts PhD Professor in the Biological Sciences department at Marquette University

MESH terms used to index this publication - Major topics in bold

Adult
Bed Rest
Electromyography
Humans
Isometric Contraction
Male
Muscle Fibers, Skeletal
Muscle, Skeletal
Myosins
Space Flight
Weightlessness