Joint Russian-Usa Field Test: Implications for Deconditioned Crew Following Long Duration Spaceflight

Abstract

A joint NASA and Institute of Biomedical Problems (IBMP) study, designated as the Field Test, was designed to investigate how the immediate post-flight effects of long duration spaceflight impact performance on vestibular and sensorimotor-related functional tasks. One unique feature of this study was the use of functional tests typically associated with everyday living to track recovery. These tasks are also expected of crewmembers during recovery operations and include sit-to-stand and prone-to-stand transitions, translating objects, and jumping down from a platform. This paper provides an overview of the methodology used for the Field Test. As an example of the functional deficits observed, we present results for a seat egress and walking task that involved turning 180 degrees and stepping over obstacles. We observed significant increases in the time-to-complete this task on landing day. We recommend this task being incorporated into Standard Measures to evaluate the efficacy of countermeasures. The decrements observed at landing day have implications for the deconditioned crew during exploration missions where crewmembers will be unassisted after landing on a planetary surface.

Multiple field tests on landing day: Early mobility may improve postural recovery following spaceflight

“…Our post-flight CDP measures reflect the high intersubject variability that characterize postural decrements following spaceflight ( Wood et al, 2015 ). This variability is consistent with other measures obtained during the Field Tests ( Reschke et al, 2020 ) as well as previous studies ( Miller et al, 2018 ; Mulavara et al, 2018 ). Nevertheless, multiple test sessions on landing day, starting early at the recovery zone, anecdotally appeared to be beneficial for some participants.…”

“…Specific expedition numbers or lengths of missions were not referenced to minimize the risk of data attributability according to NASA policy. While FT were conducted on both USOS astronauts and Russian cosmonauts ( Reschke et al, 2020 ), we limited this analysis to USOS subjects who had multiple tests on landing day and early CDP data were available. The control group had similar male/female ratio, age range, flight experience, mission duration and timing for the postflight CDP test as the FT groups ( Table 1 ).…”

“…The specific Field Test protocol has been described elsewhere ( Lee et al, 2020 ; Reschke et al, 2020 ). The common mobility tasks performed across both PFT and full FT protocols included sit-to-stand, recovery from fall (prone to stand) and tandem walk, performed in that order of increasing difficulty.…”

“…The tandem walk was the most challenging and performed last, requiring 10 heel-to-toe steps with arms crossed, and repeated with eyes closed and open. Full FT also included a timed up and go mobility test (sit-to-stand, walk 4 m, turn 180° and return to seated) with small obstacles (5–15 cm height) to step over on the return path ( Reschke et al, 2020 ). Additional full FT tasks included a standing posture test with an upper body perturbation (push) and passive dynamic visual acuity during vertical linear oscillations on a spring-loaded chair.…”

“…However, the supervised reconditioning program is typically delayed by more than 1 day while crewmembers return from the Soyuz landing site in Kazakhstan. Field Tests (FT) were conducted at the landing site to quantify functional postflight performance following long duration missions lasting ∼6 months and track their recovery ( Reschke et al, 2020 ). While not designed to be a rehabilitation-type study, the testing constraints followed similar guidelines as we propose.…”