Ground-Based Analogs for Human Spaceflight.

Meenakshi Pandiarajan,Alan R Hargens

doi:10.3389/fphys.2020.00716

Meenakshi Pandiarajan, Alan R Hargens

Open Access

https://doi.org/10.3389/fphys.2020.00716

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Journal: Frontiers in Physiology	Publication Date: Jun 23, 2020
Citations: 58	License type: CC BY 4.0

Affiliation: University of California, San Diego

Abstract

This mini-review provides an updated summary of various analogs for adaptations of humans to the microgravity of space. Microgravity analogs discussed in this paper include dry immersion, wet immersion, unilateral lower-extremity limb suspension, head down tilt (HDT), and supine bed rest. All Earth-based analogs are imperfect simulations of microgravity with their own advantages and disadvantages. This paper compares these five frequently used microgravity analogs to offer insights into their usefulness for various physiological systems. New developments for each human microgravity analog are explored and advantages of one analog are evaluated against other analogs. Furthermore, the newly observed risk of Spaceflight Associated Neuro-Ocular Syndrome (SANS) is included in this mini review with a discussion of the advantages and disadvantages of each method of simulation for the relatively new risk of SANS. Overall, the best and most integrated analog for Earth-based studies of the microgravity of space flight appears to be head-down tilt bed rest.

Highlights

This mini-review serves as an updated look upon the various analogs to microgravity
All established microgravity analogs discussed in this paper (dry immersion, wet immersion, unilateral lower-extremity limb suspension, head down tilt (HDT), and supine bed rest) are imperfect simulations of microgravity with their own merits and disadvantages
The well-established microgravity analogs discussed in this paper, dry immersion, wet immersion, unilateral lower-extremity limb suspension, HDT, and supine bed rest, have their own unique advantages and disadvantages in terms of applications to various physiological systems

Summary

Introduction

All established microgravity analogs discussed in this paper (dry immersion, wet immersion, unilateral lower-extremity limb suspension, head down tilt (HDT), and supine bed rest) are imperfect simulations of microgravity with their own merits and disadvantages. The well-established microgravity analogs discussed in this paper, dry immersion, wet immersion, unilateral lower-extremity limb suspension, HDT, and supine bed rest, have their own unique advantages and disadvantages in terms of applications to various physiological systems.

Results

Conclusion