Dataset Information

Effects of daily artificial gravity training on orthostatic tolerance following 60-day strict head-down tilt bedrest.

ABSTRACT:

Purpose

Orthostatic intolerance commonly occurs following immobilization or space flight. We hypothesized that daily artificial gravity training through short-arm centrifugation could help to maintain orthostatic tolerance following head-down tilt bedrest, which is an established terrestrial model for weightlessness.

Methods

We studied 24 healthy persons (eight women; age 33.3 ± 9.0 years; BMI 24.3 ± 2.1 kg/m²) who participated in the 60-days head-down tilt bedrest (AGBRESA) study. They were assigned to 30 min/day continuous or 6 × 5 min intermittent short-arm centrifugation with 1Gz at the center of mass or a control group. We performed head-up tilt testing with incremental lower-body negative pressure until presyncope before and after bedrest. We recorded an electrocardiogram, beat-to-beat finger blood pressure, and brachial blood pressure and obtained blood samples from an antecubital venous catheter. Orthostatic tolerance was defined as time to presyncope. We related changes in orthostatic tolerance to changes in plasma volume determined by carbon dioxide rebreathing.

Results

Compared with baseline measurements, supine and upright heart rate increased in all three groups following head-down tilt bedrest. Compared with baseline measurements, time to presyncope decreased by 323 ± 235 s with continuous centrifugation, by 296 ± 508 s with intermittent centrifugation, and by 801 ± 354 s in the control group (p = 0.0249 between interventions). The change in orthostatic tolerance was not correlated with changes in plasma volume.

Conclusions

Daily artificial gravity training on a short-arm centrifuge attenuated the reduction in orthostatic tolerance after 60 days of head-down tilt bedrest.

SUBMITTER: Hoenemann JN

PROVIDER: S-EPMC10439060 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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Publications

Effects of daily artificial gravity training on orthostatic tolerance following 60-day strict head-down tilt bedrest.

Hoenemann J-N JN Moestl S S van Herwaarden A E AE Diedrich A A Mulder E E Frett T T Petrat G G Pustowalow W W Arz M M Heusser K K Lee S S Jordan J J Tank J J Hoffmann F F

Clinical autonomic research : official journal of the Clinical Autonomic Research Society 20230622 4

<h4>Purpose</h4>Orthostatic intolerance commonly occurs following immobilization or space flight. We hypothesized that daily artificial gravity training through short-arm centrifugation could help to maintain orthostatic tolerance following head-down tilt bedrest, which is an established terrestrial model for weightlessness.<h4>Methods</h4>We studied 24 healthy persons (eight women; age 33.3 ± 9.0 years; BMI 24.3 ± 2.1 kg/m<sup>2</sup>) who participated in the 60-days head-down tilt bedrest (AGB ...[more]

PMID: 37347452

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Dataset Information

Effects of daily artificial gravity training on orthostatic tolerance following 60-day strict head-down tilt bedrest.

Purpose

Methods

Results

Conclusions

Publications

Effects of daily artificial gravity training on orthostatic tolerance following 60-day strict head-down tilt bedrest.

Similar Datasets

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