Cardiovascular dynamics among differently trained individuals during simulated microgravity exposure in the form of head-down tilt

Introduction: Human morphology and physiology are not designed inherently to function in microgravity. Hence, exposure to hypo or microgravity, as it occurs during space exploration, poses challenges in the form of peculiar adaptive physiological processes in healthy astronauts. These changes may vary (to a certain extent) depending on type of physical fitness (namely, aerobic or anaerobic) and may have definitive impact on short duration space mission. The study aimed to examine the cardiovascular dynamics during short duration exposure to simulated microgravity condition in differently trained individuals. Material and Methods: Temporal variations in body fluid distribution were studied during 6° head-down tilt (HDT) for 4-hours in 31 healthy males in age range of 20–40 years divided into three groups based on their physical training, namely; resistance trained (RT), endurance trained (ET), and untrained (UT). This was based on their history of physical training, VO2 max, and peak anaerobic power. Results: Heart rate in the ET group and RT group showed increasing and decreasing trend respectively, however, statistically remained non-significant. Systolic and diastolic pressures showed a significant increase in the ET group at the 4th h of HDT as compared to baseline and the 1st h. No significant variation in pulse pressure could be seen. Mean arterial pressures showed significant increase in the ET group at the 4th h of HDT as compared to baseline and the 1st h of HDT. Stroke volume and cardiac output did not vary significantly. Conclusion: ET individuals in the present study demonstrated decreased sensitivity of baroreceptors than RT or UT individuals, whereas, the RT group demonstrated more stability/resilience in terms of cardiovascular dynamics than ET and UT groups under exposure to short duration simulated microgravity.

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An advance in transfer line chilldown heat transfer of cryogenic propellants in microgravity using microfilm coating for enabling deep space exploration

npj Microgravity ◽

10.1038/s41526-021-00149-5 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

J. N. Chung ◽

Jun Dong ◽

Hao Wang ◽

S. R. Darr ◽

J. W. Hartwig

Keyword(s):

Space Exploration ◽

Fluid Management ◽

Microgravity Condition ◽

Space Mission ◽

Low Earth Orbit ◽

Earth Orbit ◽

Deep Space ◽

Deep Space Exploration ◽

Quenching Efficiency ◽

Proper Perspective

AbstractThe extension of human space exploration from a low earth orbit to a high earth orbit, then to Moon, Mars, and possibly asteroids is NASA’s biggest challenge for the new millennium. Integral to this mission is the effective, sufficient, and reliable supply of cryogenic propellant fluids. Therefore, highly energy-efficient thermal-fluid management breakthrough concepts to conserve and minimize the cryogen consumption have become the focus of research and development, especially for the deep space mission to mars. Here we introduce such a concept and demonstrate its feasibility in parabolic flights under a simulated space microgravity condition. We show that by coating the inner surface of a cryogenic propellant transfer pipe with low-thermal conductivity microfilms, the quenching efficiency can be increased up to 176% over that of the traditional bare-surface pipe for the thermal management process of chilling down the transfer pipe. To put this into proper perspective, the much higher efficiency translates into a 65% savings in propellant consumption.

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CD44 expression changes and increased apoptosis in MCF-7 cell line of breast cancer in simulated microgravity condition

Pars of Jahrom University of Medical Sciences ◽

10.52547/jmj.17.3.26 ◽

2019 ◽

Vol 17 (3) ◽

pp. 26-34

Author(s):

Zahra Hajebrahimi ◽

Maryam Salavatifar ◽

◽

Keyword(s):

Breast Cancer ◽

Cell Line ◽

Simulated Microgravity ◽

Microgravity Condition ◽

Cd44 Expression ◽

Mcf 7

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Alteration of cytokines expression and function in lipopolysaccharide-induced RAW264.7 cells under simulated microgravity condition

Journal of Orthopaedic Translation ◽

10.1016/j.jot.2016.06.194 ◽

2016 ◽

Vol 7 ◽

pp. 135-136

Author(s):

Dandan Dong

Keyword(s):

Simulated Microgravity ◽

Microgravity Condition ◽

Raw264.7 Cells ◽

And Function

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Mineralization initiation of MC3T3-E1 preosteoblast is suppressed under simulated microgravity condition

Cell Biology International ◽

10.1002/cbin.10391 ◽

2014 ◽

Vol 39 (4) ◽

pp. 364-372 ◽

Cited By ~ 17

Author(s):

Li-fang Hu ◽

Jing-bao Li ◽

Ai-rong Qian ◽

Fei Wang ◽

Peng Shang

Keyword(s):

Simulated Microgravity ◽

Microgravity Condition

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Improving of Special Physical Fitness and Workability of Female Police Cadets

Journal of Siberian Federal University Humanities & Social Sciences ◽

10.17516/1997-1370-0717 ◽

2021 ◽

pp. 257-265

Author(s):

Aleksander Yu. Osipov ◽

Vladimir I. Lyakh ◽

Vladimir M. Guralev ◽

Tatyana I. Ratmanskaya ◽

Mikhail D. Kudryavtsev ◽

...

Keyword(s):

Physical Fitness ◽

Police Officers ◽

Physical Training ◽

Training Programs ◽

Anaerobic Power ◽

Step Test ◽

Study Results ◽

Group 2 ◽

Crossfit Training ◽

The Impact

The importance of evaluating the physical fitness of future police officers cannot be underestimated. Ideal physical training program must include targeting aerobic capacity, anaerobic power, muscular strength and endurance. The aim of the study: investigate the impact of two additional supervised 16-week physical fitness training programs (mixed (jumping + strength endurance) workout and CrossFit training) aimed at female police cadets. Participants: relatively healthy young female (n=28) – cadets had similar indicators of physical fitness and workability. Total time of physical training – 64 hours during 16 weeks (basic workouts – 48 hours, additional workouts – 16 hours). Group 1 (n=14) practiced additional CrossFit training. Group 2 (n=14) practiced mixed additional workout (jumping + strength endurance). Tests used to evaluate the physical fitness and workability were the following: Push–Up test, Plank test, Running test, Burpee test, Step test (PWC170), test with 30 throws. The overall positive dynamics of study results shows an increase of workability for all study participants. A reliable (p≤0.05) advantage of participants (group 2) in testing workability results (Burpee test and PWC170) was found. Experts agree that the most effective physical training programs for cadets and police officers will be combinations of intensive cardiorespiratory and strength workout. A positive impact of additional mixed (jumping + strength endurance) workout on the workability of female cadets was found. Such functional workout can be an effective alternative to CrossFit training in physical training curriculum of female police cadets

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SUBSTANTIATION OF TECHNOLOGY OF INDIVIDUALIZATION OF SPECIAL PHYSICAL TRAINING FOR HIGHLY SKILLED FOOTBALL REFEREES AND ASSISTANT REFEREES

Sport Science and Human Health ◽

10.28925/2664-2069.2021.26 ◽

2021 ◽

Vol 6 (2) ◽

pp. 55-70

Author(s):

Oleg Bairachniy ◽

Taras Chopilko

Keyword(s):

Physical Fitness ◽

Short Duration ◽

Physical Training ◽

Rapid Change ◽

Professional Activities ◽

Game Situation ◽

Highly Skilled ◽

The Right ◽

Limited Period ◽

Movement Activities

Introduction. Football refereeing is constantly becoming more and more difficult due to the high dynamism, short duration and rapid change of game situations in which referees should make absolutely objective and correct decisions, withstand high levels of physical loads and psychological tension. Optimal physical fitness determines the professional activities of referees. These are the ability to control the own body and movement activities, resist fatigue, pressure of athletes and spectators, control emotions, assess the game situation adequately and make the right decision during a limited period of time. The aim of the study is to substantiate theoretically and develop the technology of individualised special physical training for football referees.

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Effects of Simulated Microgravity on Ultrastructure and Apoptosis of Choroidal Vascular Endothelial Cells

Frontiers in Physiology ◽

10.3389/fphys.2020.577325 ◽

2021 ◽

Vol 11 ◽

Author(s):

Hongwei Zhao ◽

Yuanyuan Shi ◽

Changyu Qiu ◽

Jun Zhao ◽

Yubo Gong ◽

...

Keyword(s):

Endothelial Cells ◽

Cytochrome C ◽

Protein Expression ◽

Simulated Microgravity ◽

Vascular Endothelial Cells ◽

Chromatin Condensation ◽

Microgravity Condition ◽

Vascular Endothelial ◽

Apoptosis Pathway ◽

Mrna And Protein Expression

BackgroundIt was confirmed that simulated microgravity (SMG) led to ultrastructural alterations and apoptosis in many types of microvascular endothelial cells. However, whether SMG would also affect choroidal vascular endothelial cells (CVECs) remains unknown. This study was designed to investigate the effects of SMG on ultrastructure and apoptosis of CVECs.MethodsThe rotary cell culture system (RCCS) was utilized to simulate microgravity condition. Human CVECs were cultured under normal gravity (NG) or SMG condition for 3 days. The ultrastructure was viewed under transmission electron microscopy, and the organization of F-actin was observed by immunofluorescence staining. Additionally, the apoptosis percentage was calculated using flow cytometry. Moreover, the mRNA and protein expression of BAX, Bcl-2, Caspase3, Cytochrome C, p-AKT, and p-PI3K were detected with quantitative PCR and Western blot at different exposure time.ResultsIn the SMG group, CVECs presented with a shrunk cell body, chromatin condensation and margination, mitochondria vacuolization, and apoptotic bodies. The amount of F-actin decreased, and the filaments of F-actin were sparse or even partly discontinuous after cultivation under SMG for 72 h. The proportions of apoptotic CVECs in SMG groups at 24 and 72 h were significantly higher than those in the NG group (P < 0.001). The mRNA and protein expression of Bax, Caspase3, and Cytochrome C of CVECs in SMG groups at 24 and 72 h significantly increased than those of the NG group, respectively (P < 0.001). The alterations of p-AKT and p-PI3K protein expression possessed similar trends. On the contrary, the mRNA and protein expression of Bcl-2 in CVECs under SMG at 24 and 72 h were significantly less than that of the NG group, respectively (P < 0.001).ConclusionSimulated microgravity conditions can lead the alterations of the F-actin structure and apoptosis of CVECs. The Bcl-2 apoptosis pathway and PI3K/AKT pathway may participate in the damage of CVECs caused by SMG.

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