Anthropometric Changes in Spaceflight.

OBJECTIVE: This study aims to identify the change in anthropometric measurements during spaceflight due to microgravity exposure. BACKGROUND: Comprehensive and accurate anthropometric measurements are crucial to assess body shape and size changes in microgravity. However, only limited anthropometric data have been available from the astronauts in spaceflight. METHODS: A new photogrammetry-based technique in combination with a tape-measure method was used for anthropometric measurements from nine crewmembers on the International Space Station. Measurements included circumference and height for body segments (chest, waist, bicep, thigh, calf). The time-dependent variations were also assessed across pre-, in-, and postflight conditions. RESULTS: Stature showed a biphasic change with up to 3% increase at the early flight phase, followed by a steady phase during the remaining flight. Postflight measurements returned to a similar level of the preflight. Other linear measurements, including acromion height, showed similar trends. The chest, hip, thigh, and calf circumferences show overall decrease during the flight up to 11%, then returned close to the preflight measurement at postflight. CONCLUSION: The measurements from this study provide critical information for the spacesuit and hardware design. The ground-based assessments for spacesuit fit needs to be revalidated and adjusted for in-flight extravehicular activities from this data. APPLICATION: These data can be useful for space suit design as well as habitat, vehicle, and additional microgravity activities such as exercise, where the body shape changes can affect fit, performance, and human factors of the overall design.

Changes in seated height in microgravity.

Many physiological factors, such as spinal elongation, bone atrophy, and muscle loss, occur when humans are exposed to a microgravity environment. These physiological changes can result in slight to drastic changes in body dimensions. Any drastic change in body dimensions is critical information for current and future space hardware designers. These changes can affect accommodation, safety, and performance of a crewmember while in space. This study measured the overall change in seated height and stature for crewmembers exposed to a microgravity environment. Seated height data were obtained from 29 crewmembers that included 8 International Space Station increment crew (2 females and 6 males) and 21 Shuttle crew (1 female and 20 males). The results indicate that all participating crewmembers experienced statistically significant change in seated height. The corresponding change, 6% from preflight, should be considered for vehicle designs as the necessary seated microgravity adjustment.