The Effect of the Gravity Loading Countermeasure Skinsuit Upon Movement and Strength.

Carvil, PA, Attias, J, Evetts, SN, Waldie, JM, and Green, DA. The effect of the gravity loading countermeasure skinsuit upon movement and strength. J Strength Cond Res 31(1): 154-161, 2017-Effective countermeasures against musculoskeletal deconditioning induced by microgravity and disuse are required. A simple alternative to provision of artificial gravity by centrifugation is compressive axial loading. The Russian "Pingvin" suit was the first wearable suit to apply this concept using bungee cords tethered around the shoulders and feet. However, poor loading characteristics and severe thermal and movement discomfort were reported. The gravity loading countermeasure skinsuit (GLCS) uses a bidirectional weave to generate staged axial loading from shoulders to feet, better mimicking how Earth's gravity induces progressive loading head to foot. The Mk III GLCS's loading was evaluated and tolerability assessed during maximal joint motion, ambulation, and selected strength exercises. Eight subjects (5 male and 3 female; 28 ± 3 years; 179 ± 0.1 cm and 74.8 ± 2.9 kg), having given written informed consent, had an Mk III GLCS individually tailored. Axial loading imparted, body height, joint range of motion (ROM), ambulation, and strength tests (12 repetition maximum) were performed in the GLCS and gym attire, with subjective (rating of perceived exertion, thermal comfort, movement discomfort and body control) ratings recorded throughout. Gravity loading countermeasure skinsuit provided significant axial loading when standing but significantly reduced knee (-13°), spinal (-28°) and shoulder flexion/extension ROM (-34°/-13°), in addition to Sit and Reach (-12.8 cm). No thermal issues were reported but there was an increase in subjective discomfort. Gravity loading countermeasure skinsuit did not significantly impede strength exercise, with the exception of shoulder press. The GLCS (Mk III) demonstrates potential as a countermeasure by providing tolerable, static axial loading. Furthermore, it may serve as an elasticlike strength exercise adjunct, which may have utility as a rehabilitation modality after further design refinement.

Post space mission lumbo-pelvic neuromuscular reconditioning: a European perspective.

Long-duration exposure to the space environment causes physical adaptations that are deleterious to optimal functioning on Earth. Post-mission rehabilitation traditionally concentrates on regaining general muscle strength, neuromuscular control, and lumbo-pelvic stability. A particular problem is muscle imbalance caused by the hypertrophy of the flexor and atrophy of the extensor and local lumbo-pelvic muscles, increasing the risk of post-mission injury. A method currently used in European human spaceflight to aid post-mission recovery involves a motor control approach, focusing initially on teaching voluntary contraction of specific lumbo-pelvic muscles and optimizing spinal position, progressing to functional retraining in weight bearing positions. An alternative approach would be to use a Functional Readaptive Exercise Device to appropriately recruit this musculature, thus complementing current rehabilitation programs. Advances in post-mission recovery of this nature may both improve astronaut healthcare and aid terrestrial healthcare through more effective treatment of low back pain and accelerated post bed rest rehabilitation.

A device for sampling arterialized earlobe blood in austere environments.

INTRODUCTION: There is currently no effective method of measuring arterial blood gas tensions in austere environments such as in space or at high altitude. An alternative to direct arterial measurement is the sampling of arterialized earlobe blood, an accurate technique that has been in use in clinical medicine and physiology for more than 50 yr. We, therefore, developed an earlobe arterialized blood (EAB) collector for practical use in extreme environments. METHODS: The results from the EAB collector were compared with simultaneous samples of blood drawn from the radial artery. Six healthy subjects breathed a gas mixture of 12.8% O2 in N2 during 15 min of 8 degree head-down tilt. The blood samples were analyzed immediately. RESULTS: The mean differences in Po2 between arterialized earlobe and radial artery samples were 0.25 +/- 1.25 mmHg for Po2 and 1.0 +/- 0.75 mmHg for Pco2; neither difference was significant. There was no difference between the pH values obtained by the two techniques. CONCLUSION: This study suggests that arterialized blood sampled from the earlobe using the EAB collector may provide sufficiently accurate measurements of the Po2, Pco2 and pH of arterial blood for clinical or research use in extreme environments.

Basic life support in microgravity: evaluation of a novel method during parabolic flight.

BACKGROUND: If a cardiac arrest occurs in microgravity, the aim of current emergency procedures is to treat the patient using a medical restraint system within 2 min. The patient may require treatment while medical equipment is being deployed. The capability for one person, unaided, to successfully perform cardiopulmonary resuscitation (CPR) is, therefore, of paramount importance. A new technique has been developed whereby the practitioner encircles the thorax of the patient with his/her legs to restrain the patient to allow CPR to be performed in microgravity. METHOD: Two investigators performed both this method (during parabolic microgravity) and traditional CPR (at +1 Gz) on an instrumented CPR mannequin. The mannequin was modified to ensure accurate chest compression and ventilation measurements during microgravity. RESULTS: The mean (+/-SE) depth and rate of chest compression were 44.0+/-4.99 mm and 68.3+/-17.0 compressions x min(-1) respectively. Although the mean microgravity rate of compression proved significantly less (p < 0.05) than the +1 Gz mean (97.1+/-3.4 compressions x min(-1)), chest compression depth did not differ (p > 0.05) from +1 Gz measures (43.6+/-0.59 mm). The mean (+/-SE) microgravity tidal volume (VT) was 491+/-50.4 ml, which also did not differ (p > 0.05) from +1 Gz values (507.6+/-11.5 ml). DISCUSSION: Although difficulties in performing this method during parabolic flight primarily affected compression rate, it may be possible to conduct basic life support using this technique in any microgravity environment.