Movement in low gravity environments (MoLo) programme–The MoLo-L.O.O.P. study protocol

PLoS ONE, vol. 17, pp. e0278051

Abstract

BACKGROUND: Exposure to prolonged periods in microgravity is associated with deconditioning of the musculoskeletal system due to chronic changes in mechanical stimulation. Given astronauts will operate on the Lunar surface for extended periods of time, it is critical to quantify both external (e.g., ground reaction forces) and internal (e.g., joint reaction forces) loads of relevant movements performed during Lunar missions. Such knowledge is key to predict musculoskeletal deconditioning and determine appropriate exercise countermeasures associated with extended exposure to hypogravity. OBJECTIVES: The aim of this paper is to define an experimental protocol and methodology suitable to estimate in high-fidelity hypogravity conditions the lower limb internal joint reaction forces. State-of-the-art movement kinetics, kinematics, muscle activation and muscle-tendon unit behaviour during locomotor and plyometric movements will be collected and used as inputs (Objective 1), with musculoskeletal modelling and an optimisation framework used to estimate lower limb internal joint loading (Objective 2). METHODS: Twenty-six healthy participants will be recruited for this cross-sectional study. Participants will walk, skip and run, at speeds ranging between 0.56-3.6 m/s, and perform plyometric movement trials at each gravity level (1, 0.7, 0.5, 0.38, 0.27 and 0.16g) in a randomized order. Through the collection of state-of-the-art kinetics, kinematics, muscle activation and muscle-tendon behaviour, a musculoskeletal modelling framework will be used to estimate lower limb joint reaction forces via tracking simulations. CONCLUSION: The results of this study will provide first estimations of internal musculoskeletal loads associated with human movement performed in a range of hypogravity levels. Thus, our unique data will be a key step towards modelling the musculoskeletal deconditioning associated with long term habitation on the Lunar surface, and thereby aiding the design of Lunar exercise countermeasures and mitigation strategies.

Authors 11

1. Nolan Herssens corresponding

   European Astronaut Centre

   Affiliation as printed

   Space Medicine Team, European Astronaut Centre, European Space Agency, Cologne, Germany

2. James Cowburn

   University of Bath

   Affiliation as printed

   Centre for the Analysis of Motion, Entertainment Research and Applications, University of Bath, Bath, United Kingdom

   Department for Health, University of Bath, Bath, United Kingdom

3. Kirsten Albracht Aachen Department of Medical Engineering and Technomathematics

   German Sport University Cologne · FH Aachen

   Affiliation as printed

   Centre for Health and Integrative Physiology in Space, German Sport University, Cologne, Germany

   Department of Medical Engineering and Technomathematics, University of Applied Sciences Aachen, Aachen, Germany

   Institute of Movement and Neuroscience, German Sport University, Cologne, Germany

4. Bjoern Braunstein

   German Sport University Cologne

   Affiliation as printed

   Centre for Health and Integrative Physiology in Space, German Sport University, Cologne, Germany

   German Research Centre of Elite Sport Cologne, Cologne, Germany

   Institute of Biomechanics and Orthopaedics, German Sport University, Cologne, Germany

   Institute of Movement and Neuroscience, German Sport University, Cologne, Germany

5. Dario Cazzola

   University of Bath

   Affiliation as printed

   Centre for the Analysis of Motion, Entertainment Research and Applications, University of Bath, Bath, United Kingdom

   Department for Health, University of Bath, Bath, United Kingdom

6. Steffi Colyer

   University of Bath

   Affiliation as printed

   Centre for the Analysis of Motion, Entertainment Research and Applications, University of Bath, Bath, United Kingdom

   Department for Health, University of Bath, Bath, United Kingdom

7. Alberto Enrico Minetti

   University of Milan

   Affiliation as printed

   Laboratory of Physiomechanics of Locomotion, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy

8. Gaspare Pavei

   University of Milan

   Affiliation as printed

   Laboratory of Physiomechanics of Locomotion, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy

9. Jörn Rittweger

   University of Cologne · Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)

   Affiliation as printed

   Department of Pediatrics and Adolescent Medicine, University of Cologne, Cologne, Germany

   Division of Muscle and Bone Metabolism, Institute of Aerospace Medicine DLR, Cologne, Germany

10. Tobias Weber

    European Astronaut Centre

    Affiliation as printed

    KBR, Cologne, North Rhein-Westphalia, Germany

    Space Medicine Team, European Astronaut Centre, European Space Agency, Cologne, Germany

11. David Andrew Green

    King's College London · European Astronaut Centre

    Affiliation as printed

    Centre of Human and Applied Physiological Sciences, King's College London, London, United Kingdom

    KBR, Cologne, North Rhein-Westphalia, Germany

    Space Medicine Team, European Astronaut Centre, European Space Agency, Cologne, Germany

    Centre of Human and Applied Physiological Sciences, King’s College London, London, United Kingdom