Lunar and mars gravity induce similar changes in spinal motor control as microgravity

Frontiers in Physiology

Physiology

David A. Green¹  Christopher A. Easthope²  Anke Langenfeld³  Petra Schweinhardt³  Anita Meinke³  Jaap Swanenburg⁴ 

[1] Centre of Human and Applied Physiological Sciences, King’s College London, London, United Kingdom;Space Medicine Team, European Astronaut Centre, European Space Agency, Cologne, Germany;KBRwyle GmbH, Cologne, Germany;Cereneo—Center for Interdisciplinary Research, Vitznau, Switzerland;Lake Lucerne Institute, Vitznau, Switzerland;Department of Chiropractic Medicine, Integrative Spinal Research ISR, Balgrist University Hospital, Zürich, Switzerland;Department of Chiropractic Medicine, Integrative Spinal Research ISR, Balgrist University Hospital, Zürich, Switzerland;Faculty of Medicine, Institute of Anatomy, University of Zurich, Zurich, Switzerland;Innovation Cluster Space and Aviation (UZH Space Hub), Air Force Center, University of Zurich, Dübendorf, Switzerland;

关键词: stiffness;    spine;    microgravity;    hypergravity;    lunar;    lumbar;    parabolic flight;   

DOI  :  10.3389/fphys.2023.1196929

 received in 2023-03-30, accepted in 2023-07-13,  发布年份 2023

来源: Frontiers

【 摘 要 】

Introduction: Once more, plans are underway to send humans to the Moon or possibly even to Mars. It is therefore, important to know potential physiological effects of a prolonged stay in space and to minimize possible health risks to astronauts. It has been shown that spinal motor control strategies change during microgravity induced by parabolic flight. The way in which spinal motor control strategies change during partial microgravity, such as that encountered on the Moon and on Mars, is not known.Methods: Spinal motor control measurements were performed during Earth, lunar, Mars, and micro-gravity conditions and two hypergravity conditions of a parabola. Three proxy measures of spinal motor control were recorded: spinal stiffness of lumbar L3 vertebra using the impulse response, muscle activity of lumbar flexors and extensors using surface electromyography, and lumbar curvature using two curvature distance sensors placed at the upper and lower lumbar spine. The participants were six females and six males, with a mean age of 33 years (standard deviation: 7 years).Results: Gravity condition had a statistically significant (Friedmann tests) effect spinal stiffness (p < 0.001); on EMG measures (multifidus (p = 0.047), transversus abdominis (p < 0.001), and psoas (p < 0.001) muscles) and on upper lumbar curvature sensor (p < 0.001). No effect was found on the erector spinae muscle (p = 0.063) or lower curvature sensor (p = 0.170). Post hoc tests revealed a significant increase in stiffness under micro-, lunar-, and Martian gravity conditions (all p’s < 0.034). Spinal stiffness decreased under both hypergravity conditions (all p’s ≤ 0.012) and decreased during the second hypergravity compared to the first hypergravity condition (p = 0.012).Discussion: Micro-, lunar-, and Martian gravity conditions resulted in similar increases in spinal stiffness, a decrease in transversus abdominis muscle activity, with no change in psoas muscle activity and thus modulation of spinal motor stabilization strategy compared to those observed under Earth’s gravity. These findings suggest that the spine is highly sensitive to gravity transitions but that Lunar and Martian gravity are below that required for normal modulation of spinal motor stabilization strategy and thus may be associated with LBP and/or IVD risk without the definition of countermeasures.

【 授权许可】

Unknown   
Copyright © 2023 Swanenburg, Easthope, Meinke, Langenfeld, Green and Schweinhardt.