Artificial gravity as a countermeasure for mitigating physiological deconditioning during long-duration space missions

Gilles R Clément, Angelia P Bukley, William H Paloski, Gilles R Clément, Angelia P Bukley, William H Paloski

Abstract

In spite of the experience gained in human space flight since Yuri Gagarin's historical flight in 1961, there has yet to be identified a completely effective countermeasure for mitigating the effects of weightlessness on humans. Were astronauts to embark upon a journey to Mars today, the 6-month exposure to weightlessness en route would leave them considerably debilitated, even with the implementation of the suite of piece-meal countermeasures currently employed. Continuous or intermittent exposure to simulated gravitational states on board the spacecraft while traveling to and from Mars, also known as artificial gravity, has the potential for enhancing adaptation to Mars gravity and re-adaptation to Earth gravity. Many physiological functions are adversely affected by the weightless environment of spaceflight because they are calibrated for normal, Earth's gravity. Hence, the concept of artificial gravity is to provide a broad-spectrum replacement for the gravitational forces that naturally occur on the Earth's surface, thereby avoiding the physiological deconditioning that takes place in weightlessness. Because researchers have long been concerned by the adverse sensorimotor effects that occur in weightlessness as well as in rotating environments, additional study of the complex interactions among sensorimotor and other physiological systems in rotating environments must be undertaken both on Earth and in space before artificial gravity can be implemented.

Keywords: adaptation; centrifuge; countermeasure; gravity; international space station; microgravity.

Figures

Figure 1
Figure 1
Artificial gravity. Continuous rotation of a large spacecraft that creates a centrifugal force of 1 G in the habitat would give the static crewmembers the sensation of standing upright as on Earth. The magnitude of the centrifugal force is function of the square of the rotation rate (ω) times the distance (r) from the axis of rotation. In the example of the spacecraft shown in the insert, a 4-rpm rotation rate would generate 1 G in the crew habitat located at 56 m from the axis of rotation.
Figure 2
Figure 2
Hypothetical comfort zone bounded by values of artificial gravity level and rotation rate based on theoretical studies in the 1960s (see Hall, , for details). The “comfort zone” is the area in blue delimited by a maximum rotation rate of 6 rpm. According to the model of Stone and Letko (1965) the Coriolis and cross-coupled angular accelerations generated at these rotation rates during walking, climbing and handling materials should be the most comfortable for the crewmembers. However, very little experimental data were actually collected to validate this model. Recent data indicate that the limit of 6 rpm is overly conservative.
Figure 3
Figure 3
Constraints for short-radius centrifugation. On Earth, the actual forces exerted on the body during centrifugation are the resultant of the gravitational force (in blue) and the centrifugal (inertial) forces (in red). These gravito-inertial forces (in green) are larger than 1 G and tilted relative to vertical. In space, the centrifugal forces are the only forces generated by centrifugation and aligned with the longitudinal body axis. Note also the gravity gradient, i.e., the different magnitude of centrifugal force along the longitudinal body axis.
Figure 4
Figure 4
Rationale for evaluating the effects of intermittent short-radius centrifugation during bed rest.
Figure 5
Figure 5
Rationale for evaluating the effects of Martian gravity during head-up tilt.
Figure 6
Figure 6
Partial-gravity simulators. (A) A harness connected to a rolling-trolley mechanism ensures that only a vertical force is applied to the subject. (B) Subject walking on a treadmill with lower body positive pressure (LBPP) support that reduces weight bearing. (C) The reduced-gravity walking simulator at NASA Langley Research Center used long cables to support a subject walking on a tilted surface Photo credit: NASA.

References

    1. Antonutto G., Linnarsson D., di Prampero P. E. (1993). On-Earth evaluation of neurovestibular tolerance to centrifuge simulated artificial gravity in humans. Physiologist 36, S85–S87.
    1. Arrott A. P., Young L. R., Merfeld D. M. (1990). Perception of linear acceleration in weightlessness. Aviat. Space Environ. Med. 61, 319–326.
    1. Benson A. J., Guedry F. E., Parker D. E., Reschke M. F. (1997). Microgravity vestibular investigations: perception of self-orientation and self-motion. J. Vestib. Res. 7, 453–457. 10.1016/S0957-4271(96)00167-X
    1. Benson A. J., Kass J. R., Vogel H. (1986). European vestibular experiments on the Spacelab-1 mission: 4. Thresholds of perception of whole-body linear oscillation. Exp. Brain Res. 64, 264–271. 10.1007/bf00237742
    1. Caiozzo V. J., Rose-Gottron C., Baldwin K. M., Cooper D., Adams G., Hicks J. (2004). Hemodynamic and metabolic responses to hypergravity on a human-powered centrifuge. Aviat. Space Environ. Med. 75, 101–108.
    1. Cavanagh P. R., Rice A. J., Licata A. A., Kuklis M. M., Novotny S. C., Genc K. O., et al. . (2013). A novel lunar bed rest analogue. Aviat. Space Environ. Med. 84, 1191–1195. 10.3357/asem.3472.2013
    1. Clément G. (2011). Fundamentals of Space Medicine. 2nd Edn. New York, NY: Springer.
    1. Clément G., Bukley A. P. (2007). Artificial Gravity. Hawthorne, CA: Microcosm Inc.
    1. Clément G., Deliere Q., Migeotte P. F. (2014). Perception of verticality and cardiovascular responses during short-radius centrifugation. J. Vestib. Res. 24, 1–8. 10.3233/VES-130504
    1. Clément G., Moore S., Raphan T., Cohen B. (2001). Perception of tilt (somatogravic illusion) in response to sustained linear acceleration during space flight. Exp. Brain Res. 138, 410–418. 10.1007/s002210100706
    1. Clément G., Pavy-Le Traon A. (2004). Centrifugation as a countermeasure during actual and simulated microgravity: a review. Eur. J. Appl. Physiol. 92, 235–248. 10.1007/s00421-004-1118-1
    1. Clément G., Reschke M. F. (2008). Neuroscience in Space. New York, NY: Springer.
    1. Crosbie R. J. (1960). Explicit Expressions for the Angular Accelerations and Linear Accelerations Developed at a Point Off Center in a Gondola Mounted with a Three Gimbal System on the End of a Moving Centrifuge Arm. NADC MA 6034, Patent US5021982.
    1. de Winkel K., Clément G., Werkhoven P., Groen E. (2012). Human threshold for gravity perception. Neurosci. Lett. 529, 7–11. 10.1016/j.neulet.2012.09.026
    1. Diamandis P. H. (1997). “Countermeasure and artificial gravity,” in Fundamentals of Space Life Sciences, ed. Churchill S. E. (Malabar, FL: Krieger; ), 159–175.
    1. di Prampero P. E. (2000). Cycling on earth, in space, on the moon. Eur. J. Appl. Physiol. 82, 345–360. 10.1007/s004210000220
    1. Graybiel A., Clark B., Zarriello J. J. (1960). Observations on human subjects living in a “slow rotation room” for periods of two days. Arch. Neurol. 3, 55–73. 10.1001/archneur.1960.00450010055006
    1. Graybiel A., Dean F. R., Colehour J. K. (1969). Prevention of overt motion sickness by incremental exposure to otherwise highly stressful Coriolis accelerations. Aerosp. Med. 40, 142–148.
    1. Graybiel A., Kennedy R. S., Knoblock E. C., Guedry F. E., Mertz W., McLeod M. W., et al. . (1965). Effects of exposure to a rotating environment (10 RPM) on four aviators for a period of twelve days. Aerosp. Med. 36,733–754.
    1. Graybiel A., Miller E. F., Homick J. L. (1977). “Experiment M131. Human vestibular function,” in Biomedical Results from Skylab (NASA SP-377), eds Johnston R. S., Dietlein L. F. (Washington, DC: U.S. Government Printing Office; ), 74–103.
    1. Greenleaf J. E., Gundo D. P., Watenpaugh D. E., Mulenburg G. M., McKenzie M. A., Looft-Wilson R., et al. . (1996). Cycle-powered short radius (1.9M) centrifuge: exercise vs. passive acceleration. J. Gravit. Physiol. 3, 61–62.
    1. Guedry F. E., Benson A. J. (1978). Coriolis cross-coupling effects: disorienting and nauseogenic or not. Aviat. Space Environ. Med. 49, 29–35.
    1. Guedry F. E., Kennedy R. S., Harris D. S., Graybiel A. (1964). Human performance during two weeks in a room rotating at three RPM. Aerosp. Med. 35, 1071–1082.
    1. Guinet P., Schneider S., Macias B., Watenpaugh D., Hughson R., Pavy-Le Traon A., et al. . (2009). WISE-2005: effect of aerobic and resistive exercises on orthostatic tolerance during 60 days bed rest in women. Eur. J. Appl. Physiol. 106, 217–227. 10.1007/s00421-009-1009-6
    1. Hall T. W. (2009). “Artificial gravity,” in Out of This World: The New Field of Space Architecture, eds Howe A. S., Sherwood B. (Reston, VA: American Institute of Aeronautics and Astronautics; ), 12, 133–152.
    1. Harford J. (1973). Korolev. New York: Wiley.
    1. Harris L. R., Herpers R., Hofhammer T., Jenkin M. (2014). How much gravity is needed to establish the perceptual upright? PLOS One 9:e106207. 10.1371/journal.pone.0106207
    1. Iwasaki K., Hirayanagi K., Sasaki T., Kinoue T., Ito M., Miyamoto A., et al. . (1998). Effects of repeated long duration +2Gz load on man’s cardiovascular function. Acta Astronaut. 42, 175–183. 10.1016/s0094-5765(98)00115-5
    1. Iwasaki K., Sasaki T., Hirayanagi K., Yajima K. (2001). Usefulness of daily +2Gz load as a countermeasure against physiological problems during weightlessness. Acta Astronaut. 49, 227–235. 10.1016/s0094-5765(01)00101-1
    1. Iwasaki K., Shiozawa T., Kamiya K., Michikami D., Hirayanagi K., Yajima K., et al. . (2005). Hypergravity exercise against bed rest induced changes in cardiac autonomic control. Eur. J. Appl. Physiol. 94, 285–291. 10.1007/s00421-004-1308-x
    1. Iwase S. (2005). Effectiveness of centrifuge-induced artificial gravity with ergometric exercise as a countermeasure during simulated microgravity exposure in humans. Acta Astronaut. 57, 75–80. 10.1016/j.actaastro.2005.03.013
    1. Jarchow T., Young L. R. (2010). Neurovestibular effects of bed rest and centrifugation. J. Vestib. Res. 20, 45–51. 10.3233/VES-2010-0350
    1. Katayama K., Sato K., Akima H., Ishida K., Takada H., Watanabe Y. (2004). Acceleration with exercise during head down bed rest preserves upright exercise responses. Aviat. Space Environ. Med. 75, 1029–1035.
    1. Kennedy R. S., Graybiel A. (1962). Symptomatology during prolonged exposure in a constantly rotating environment at a velocity of one revolution per minute. Aerosp. Med. 33, 817–825.
    1. Kos O., Hughson R. L., Hart D. A., Clément G., Frings-Meuthen P., Linnarsson D., et al. . (2014). Elevated serum soluble CD200 and CD200R as surrogate markers of bone loss under bed rest conditions. Bone 60, 33–40. 10.1016/j.bone.2013.12.004
    1. Lackner J. R., DiZio P. (2000). Human orientation and movement control in weightless and artificial gravity environments. Exp. Brain Res. 130, 2–26. 10.1007/s002210050002
    1. Lee S., Bennett B., Hargens A., Watenpaugh D., Ballard R., Murthy G., et al. . (1997). Upright exercise or supine lower body negative pressure exercise maintains exercise responses after bed rest. Med. Sci. Sports Exerc. 29, 892–900. 10.1097/00005768-199707000-00008
    1. Letko W., Spady A. A. (1970). “Walking in simulated lunar gravity,” in Fourth Symposium on the Role of the Vestibular Organs in Space Exploration (NASA SP-187), ed Graybiel A. (Washington, DC: NASA; ), 347–351.
    1. Linnarsson D., Hughson R. L., Fraser K., Clément G., Karlsson L., Mulder E., et al. . (2015). Effects of an artificial gravity countermeasure on orthostatic tolerance, blood volumes and aerobic capacity after short-term bed rest. J. Appl. Physiol. (1985) 118, 29–35. 10.1152/japplphysiol.00061.2014
    1. Macias B. R., Cao P., Watenpaugh D. E., Hargens A. R. (2007). LBNP treadmill exercise maintains spine function and muscle strength in identical twins during 28-day simulated microgravity. J. Appl. Physiol. (1985) 102, 2274–2278. 10.1152/japplphysiol.00541.2006
    1. Mader T. H., Gibson C. R., Pass A. F., Kramer L. A., Lee A. G., Fogarty J., et al. . (2011). Optic disc edema, globe flattening, choroidal folds and hyperopic shifts observed in astronauts after long-duration space flight. Ophthalmology 118, 2058–2069. 10.1016/j.ophtha.2011.06.021
    1. Moore S., Diedrich A., Biaggioni I., Kaufmann H., Raphan T., Cohen B. (2005). Artificial gravity: a possible countermeasure for post-flight orthostatic intolerance. Acta Astronaut. 56, 867–876. 10.1016/j.actaastro.2005.01.012
    1. Moore S., MacDougall H. G., Paloski W. H. (2010). Effects of head-down bed rest and artificial gravity on spatial orientation. Exp. Brain Res. 204, 617–622. 10.1007/s00221-010-2317-0
    1. Mulder E., Linnarsson D., Paloski W. H., Rittweger J., Wuyts F., Zange J., et al. . (2014). Effects of five days of bed rest with and without exercise countermeasure on postural stability and gait. J. Musculoskelet. Neuronal Interact. 14, 359–366.
    1. Noordung H. (1928). The Problem of Space Travel: The Rocket Motor. Darby, PA: Diane Publishing Co.
    1. Oberth H. (1923). The Rocket Into Interplanetary Space. Munich: Oldenbourg.
    1. O’Neill G. K. (1977). The High Frontier. New York: William Morrow.
    1. Pavy-Le Traon A., Allevard A. M., Fortrat J. O., Vasseur P., Gauquelin G., Guell A., et al. . (1997). Cardiovascular and hormonal changes induced by a simulation of a lunar mission. Aviat. Space Environ. Med. 68, 829–837.
    1. Reschke M. F., Bloomberg J. J., Paloski W. H., Mulavara A. P., Feiveson A. H., Harm D. L. (2009). Postural reflexes, balance control and functional mobility with long-duration head-down bed rest. Aviat. Space Environ. Med. 80, A45–A54. 10.3357/asem.br06.2009
    1. Sawin C. F., Baker E., Black F. O. (1998). Medical investigations and resulting countermeasures in support of 16-day space shuttle missions. J. Gravit. Physiol. 5, 1–12.
    1. Schneider S., Watenpaugh D., Lee S., Ertl A., Williams W., Ballard R., et al. . (2002). Lower-body negative-pressure exercise and bed-rest mediated orthostatic tolerance. Med. Sci. Sports Exerc. 34, 1446–1453. 10.1097/00005768-200209000-00008
    1. Seaton K. A., Slack K. J., Sipes W. A., Bowie K. E. (2009). Cognitive functioning in long-duration head-down bed rest. Aviat. Space Environ. Med. 80, A62–A65. 10.3357/asem.br09.2009
    1. Shackelford L. C., LeBlanc A. D., Driscoll T. B., Evans H. J., Rianon N. J., Smith S. M., et al. . (2004). Resistance exercise as a countermeasure to disuse-induced bone loss. J. Appl. Physiol. (1985) 97, 119–129. 10.1152/japplphysiol.00741.2003
    1. Shibata S., Perhonen M., Levine B. (2010). Supine cycling plus volume loading prevent cardiovascular deconditioning during bed rest. J. Appl. Physiol. (1985) 108, 1177–1786. 10.1152/japplphysiol.01408.2009
    1. Smith S., Zwart S., Heer M., Baecker N., Evans H., Feiveson A., et al. . (2009). Effects of artificial gravity during bed rest on bone metabolism in humans. J. Appl. Physiol. (1985) 107, 47–53. 10.1152/japplphysiol.91134.2008
    1. Stone R. W. (1973). “An overview of artificial gravity,” in Proceedings of the Fifth Symposium on the Role of the Vestibular Organs in Space Exploration (NASA SP-314), ed Graybiel A. (Pensacola, FL: Naval Aerospace Medical Center; ), 23–33.
    1. Stone R. W., Letko W. (1965). “Some observations on the stimulation of the vestibular system of man in a rotating environment,” in The Role of the Vestibular Organs in the Exploration of Space (NASA SP-77), ed. Graybiel A. (Washington, DC: NASA; ), 263–277.
    1. Takacs J., Anderson J. E., Leiter J. R., MacDonald P. B., Peeler J. (2013). Lower body positive pressure: an emerging technology in the battle against knee osteoarthritis? Clin. Interv. Aging 8, 983–991. 10.2147/CIA.s46951
    1. Von Braun W. (1953). The baby space station: first step in the conquest of space. Collier’s Magazine. 27, 33–35, 38,, 40.
    1. Watenpaugh D., O’Leary D., Schneider S., Lee S., Macias B., Tanaka K., et al. . (2007). Lower body negative pressure exercise plus brief post-exercise lower body negative pressure improve post-bed rest orthostatic tolerance. J. Appl. Physiol. (1985) 103, 1964–1972. 10.1152/japplphysiol.00132.2007
    1. Wu R. H. (1999). Human Readaptation to Normal Gravity following Short-Term simulated Martian Gravity Exposure and the Effectiveness of Countermeasures. Master of Sciences Thesis. Cambridge, MA: Massachusetts Institute of Technology.
    1. Young L. R., Hecht H., Lyne L. E., Sienko K. B., Cheung C. C., Kavelaars J. (2001). Artificial gravity: head movements during short-radius centrifugation. Acta Astronaut. 49, 215–226. 10.1016/s0094-5765(01)00100-x
    1. Young L. R., Paloski W. E., Fuller C. F. (2006). Artificial Gravity as a Tool in Biology and Medicine. Final Report. Study Group 2.2. Paris: International Academy of Astronautics.
    1. Zwart S., Hargens A., Lee S., Macias B., Watenpaugh D. E., Tse K., et al. . (2007). Lower body negative pressure treadmill exercise as a countermeasure for bed rest-induced bone loss in female identical twins. Bone 40, 529–537. 10.1016/j.bone.2006.09.014

Source: PubMed

Sponsors et collaborateurs

Les conditions médicales

Interventions en matière de drogue

3
S'abonner