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Quantification of In-flight Physical Changes - Anthropometry and Neutral Body Posture (NBP) (Body_Measures)
Principal Investigator
Research Area:
Human factors
Species Studied
Scientific Name: Homo sapiens Species: Human

NASA suit engineers and the Extravehicular Activity (EVA) Project Office have identified that suit fit in microgravity could become an issue, as evidenced during a recent incident on-board the International Space Station (ISS). It has also been noted that crewmembers often need to adjust their suit sizing once they are in orbit. This adjustment could be due to microgravity effects on anthropometry and postural changes, and is necessary to ensure optimal crew performance, fit, and comfort in space. To date, the only data collected in space to determine the effects of microgravity on physical human changes have been during Skylab, STS-57, and a recent Human Research Program (HRP) study on seated height changes due to spinal elongation, Spinal Elongation (Young, 2011). Skylab and the STS-57 studies found that there is a distinct neutral body posture (NBP) based on photographs. Additionally, Skylab studies found that crewmembers could experience a stature growth of up to 3 percent. The Spinal Elongation study in 2011 identified that the crewmembers could experience about a 6 percent growth in seated height and a 3 percent stature growth when exposed to a microgravity environment. The results prove that not all anthropometric measurements have the same microgravity percent growth factor. In order for the EVA Project Office and the suit engineers to properly update the sizing protocol for microgravity, they need additional anthropometric data from space. Hence, this study was recommended by the ISS and sponsored and funded by the EVA Project Office to gather additional in-flight anthropometric measurements, such as lengths, depths, breadths, and circumferences to determine the changes to body shape and size due to microgravity effects. It was anticipated that by recording the potential changes to body shape and size, a better suit sizing protocol could be developed for ISS and other space missions. In essence, this study aimed to help NASA quantify the impacts of microgravity on anthropometry to ensure optimal crew performance, fit, and comfort. Additional in-flight physical changes due to NBP and the effects of spaceflight on NBP during extended exposure to microgravity also needed to be quantified. This study used simplistic data collection techniques as well as digital still and video data to perform photogrammetric analyses and determine the changes that occur to the body shape, size, and NBP while exposed to a microgravity environment.

The objectives were:
1. To initiate an activity to gather and document microgravity effects on body measurements: lengths, breadths, widths, circumferences, and joint angles of subjects exposed to microgravity in an unsuited condition.

2. To determine if/how the NBP is influenced by the above factors.

3. This was the first time these proposed measures were collected in space. It was anticipated that body measurements would change due to microgravity and fluid shifts. The goal of this study was to gather preliminary data to better understand the magnitude and variability of these changes. This data is important for NASA to be able to determine the changes that may occur during long-duration space flight and once obtained, NASA engineers may be able to apply these changes to suit fit, suit sizing, work station design, etc. for current and near future missions. These changes will help NASA to prevent potential crew injury during extended on-orbit missions.

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Data Information
Data Availability
Archive is complete. Data sets are not publicly available but can be requested.
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Acromion height
Biacromion height
Bicep circumference
Calf circumference
Chest breadth
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Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
Expedition 37 09/10/2013 11/10/2013 61 days
Expedition 38 11/10/2013 03/10/2014 120 days
Expedition 39 03/10/2014 05/13/2014 64 days
Expedition 40 05/13/2014 09/10/2014 133 days
Expedition 41 09/10/2014 11/09/2014 29 days
Expedition 42 11/10/2014 03/11/2015 121 days
Expedition 43 03/11/2015 06/10/2015 91 days
Expedition 44 06/10/2015 09/11/2015 93 days
Expedition 45 09/11/2015 12/11/2015 91 days
Expedition 46 12/11/2015 03/02/2016 82 days
Expedition 47 03/02/2016 06/18/2016 108 days
Expedition 48 06/18/2016 09/06/2016 80 days
Expedition 49 09/06/2016 10/30/2016 54 days
Expedition 50 10/28/2016 04/09/2017 164 days
Expedition 51 04/09/2017 06/02/2017 55 days
Expedition 52 06/02/2017 09/02/2017 92 days

Human Research Program (HRP) Human Research Roadmap (HRR) Information
Crew health and performance is critical to successful human exploration beyond low Earth orbit. The Human Research Program (HRP) investigates and mitigates the highest risks to human health and performance, providing essential countermeasures and technologies for human space exploration. Risks include physiological and performance effects from hazards such as radiation, altered gravity, and hostile environments, as well as unique challenges in medical support, human factors, and behavioral health support. The HRP utilizes an Integrated Research Plan (IRP) to identify the approach and research activities planned to address these risks, which are assigned to specific Elements within the program. The Human Research Roadmap is the web-based tool for communicating the IRP content.

The Human Research Roadmap is located at:

+ Click here for information of how this experiment is contributing to the HRP's path for risk reduction.

Additional Information
Other Key People
Managing NASA Center
Johnson Space Center (JSC)
Responsible NASA Representative
Johnson Space Center LSDA Office
Project Manager: Pamela A. Bieri
Institutional Support
National Aeronautics and Space Administration (NASA)
Alternate Experiment Name
Proposal Date
Proposal Source
Directed Research