The Gravity-Loading countermeasure Skinsuit (GLCS) and its effect upon aerobic exercise performance

Abstract

The Russian Pingvin suit is employed as a countermeasure to musculoskeletal atrophy in microgravity, though its 2-stage loading regime is poorly tolerated. The Gravity-Loading Countermeasure Skinsuit (GLCS) has been devised to comfortably compress the body via incrementally increasing longitudinal elastic-fibre tensions from the shoulders to the feet. We tested whether the Mk III GLCS was a feasible adjunct to sub-maximal aerobic exercise and resulting VO 2 Max predictions. Eight healthy subjects (5♂, 28 ± 6 yr) performed cycle ergometry at 75% VO 2 Max (derived from an Astrand-Rhyming protocol) whilst wearing a GLCS and gym clothing (GYM). Ventilatory parameters, heart rate (H R), core temperature (T C), and blood lactate (B L) were recorded along with subjective perceived exertion, thermal comfort, movement discomfort and body control. Physiological and subjective responses were compared over TIME and between GYM and GLCS (ATTIRE) with 2-way repeated measures ANOVA and Wilcoxon tests respectively. Resultant VO 2 Max predictions were compared with paired ttests between ATTIRE. The GLCS induced greater initial exercise ventilatory responses which stabilised by 20 min. H R and T C continued to rise from 5 min irrespective of ATTIRE, whereas B L was greater in the GLCS at 20 min. Predicted V O 2 Max did not differ with ATTIRE, though some observed differences in H R were noteworthy. All subjective ratings were exacerbated in the GLCS. Despite increased perception of workload and initial ventilatory augmentations, submaximal exercise performance was not impeded. Whilst predicted VO 2 Max did not differ, determination of actual VO 2 Max in the GLCS is warranted due to apparent modulation of the linear H R-VO 2 relationship. The GLCS may be a feasible adjunct to exercise and potential countermeasure to unloaded-induced physiological deconditioning on Earth or in space.

Spinal Health during Unloading and Reloading Associated with Spaceflight

“…To address the Pengvin Suit's limitations, the Gravity Loading Countermeasure SkinSuit (GLCS) was conceived to produce “1 Gz” using elastic fibers to generate multi-stage tension (that accumulates according to the proportion of body mass) in the vertical axis toward the feet (Waldie and Newman, 2011 ). Following various prototypes, the Mk III GLCS was found to provide ~0.7 Gz (measured at the feet) and shown to be compatible with acute strength (Carvil et al, 2017a ) and aerobic exercise (Attias et al, 2017 ). Following several critical design and material innovations, the Mk VI SkinSuit was developed by ESA's Space Medicine Office and King's College London to specifically address whether the modified SkinSuit could reduce in-flight spinal elongation, without being uncomfortable or interfering with nominal ISS spaceflight activities.…”

Developing Proprioceptive Countermeasures to Mitigate Postural and Locomotor Control Deficits After Long-Duration Spaceflight

“…A similar concept called the Gravity Loading Countermeasure Skinsuit (GLCS) was designed to improve comfort and loading characteristics. Although promising test results suggest that the GLCS may be beneficial as an adjunct to exercise ( Attias et al, 2017 ; Carvil et al, 2017 ), the efficacy of this loading strategy for postural and locomotor control has not been directly tested in a randomized controlled trial. The axial loading by itself may not be sufficient to protect against post-flight balance impairments.…”

Back Pain in Outer Space

“…Whereas the Gravity Loading Countermeasure Skinsuit has improved upon many measures, remaining challenges for extended missions include higher minute ventilation during exercise testing, variance in fit, and impaired joint motion. 39–41…”

“…Whereas the Gravity Loading Countermeasure Skinsuit has improved upon many measures, remaining challenges for extended missions include higher minute ventilation during exercise testing, variance in fit, and impaired joint motion. [39][40][41] Stress and trauma Secondary to Space Vehicular travel Whole body vibration, high gravitational force equivalents, and vectored forces creating abnormal postural stresses (e.g., abnormally directed forces on spine curvature) are a potential source of space adaptation back pain. These risks have been studied for years in rotary wing aviation and high-performance jets, and numerous countermeasures have been developed to mitigate their effects on aircrew including exercise, stretching, reconditioning, traction, and behavioral interventions.…”