Project

The Gravity Loading Countermeasure Skinsuit

Copyright

Rachel Frances Bellisle

Rachel Frances Bellisle

By Rachel Bellisle

The Gravity Loading Countermeasure Skinsuit (or “Skinsuit”) is an intravehicular activity suit for astronauts that has been developed to simulate the effects of Earth gravity. The Skinsuit produces a static load from the shoulders to the feet with elastic material in the form of a skin-tight wearable suit [1],[2]. This wearable system is intended to supplement exercise during future missions to the moon and Mars (where current exercise equipment may be too large and bulky for the small spacecraft) and to further attenuate microgravity-induced physiological effects in current ISS mission scenarios. 

By Rachel Bellisle

The Gravity Loading Countermeasure Skinsuit (or “Skinsuit”) is an intravehicular activity suit for astronauts that has been developed to simulate the effects of Earth gravity. The Skinsuit produces a static load from the shoulders to the feet with elastic material in the form of a skin-tight wearable suit [1],[2]. This wearable system is intended to supplement exercise during future missions to the moon and Mars (where current exercise equipment may be too large and bulky for the small spacecraft) and to further attenuate microgravity-induced physiological effects in current ISS mission scenarios. 

Copyright

Rachel Frances Bellisle

The Skinsuit targets multiple physiological systems, aiming to mitigate spaceflight-induced musculoskeletal adaptations, such as spinal elongation. Additionally, the Skinsuit may provide benefits to the sensorimotor system, which have not been tested in previous studies. The sensorimotor effects of microgravity are difficult to simulate on Earth, even in bed rest analogs or body-weight suspension, due to the constant force of gravity on the body and body-load receptors. The goal of this project is to use the microgravity afforded by a parabolic flight to explore a research question: Can the Skinsuit restore sensorimotor functions that are typically altered in microgravity?

Microgravity unloading affects body-load receptors, such as mechanoreceptors in the skin and muscles. In combination with adaptations in the vestibular system, sensorimotor adaptations may affect posture, locomotion, balance, and proprioception upon return to Earth [3]. Our hypothesis is that Skinsuit loading (including axial body load and foot pressure) will cause an increase in postural muscle activity in reduced gravity environments, partially restoring the muscle activity levels typically seen in 1G. If proven correct, this hypothesis would indicate that the Skinsuit could provide muscle atrophy attenuation and prevent the degradation of typical 1G motor control strategies. By maintaining typical 1G motor control strategies in parallel to microgravity adaptations, we aim to move toward dual adaptation to different gravity levels, allowing astronauts to more rapidly adjust to 1G upon return to Earth.

Copyright

Rachel Frances Bellisle

Several Skinsuit versions have been developed over the past decade with various design modifications (Figure 2)[4]. Previous Skinsuit experiments, including ground experiments, parabolic flights, and ISS flights, have primarily studied operational feasibility, loading magnitude, and spinal elongation attenuation. The investigation of sensorimotor effects and microgravity EMG patterns associated with the Skinsuit is novel.

The experimental protocol for the flight was developed over the course of the Fall 2020 semester, and experiment measurables will include electromyography (EMG) and foot pressure. During the flight, the participant will perform arm movements with and without the Skinsuit for comparison to typical 1-G muscle activation patterns and postural control strategies. In parallel to developing an experimental protocol to answer questions about physiology, we have also designed and fabricated the next-generation Skinsuit [5] (Figure 1).

This work aims to characterize the function and physiological effects of the Skinsuit and may elucidate short-term changes in human sensorimotor function in microgravity. Overall, the proposed work would support the goal of the Skinsuit project in enabling humans to adapt to multiple levels of gravity, bringing us one step closer to long-term space habitation.

[1] Waldie, J. M., & Newman, D. J. (2011). A gravity loading countermeasure skinsuit. Acta Astronautica68, 722–730. https://doi.org/10.1016/j.actaastro.2010.07.022

[2] Waldie, J. M., & Newman, D. J. (2014). Gravity-Loading Body Suit.

[3] English, K. L., Bloomberg, J. J., Mulavara, A. P., & Ploutz-Snyder, L. L. (2020). Exercise Countermeasures to Neuromuscular Deconditioning in Spaceflight. Comprehensive Physiology10, 171–196. https://doi.org/10.1002/cphy.c190005

[4] Bellisle, R., & Newman, D. (2020). Countermeasure suits for spaceflight. In 50th International Conference on Environmental Systems. Retrieved from https://ttu-ir.tdl.org/handle/2346/86259

[5] Bellisle, R., Bjune, C., & Newman, D. (2020). Considerations for Wearable Sensors to Monitor Physical Performance During Spaceflight Intravehicular Activities. In Annual International Conferences of the IEEE Engineering in Medicine and Biology Society (pp. 4160–4164).