On-Orbit Evaluation of a New Treadmill Harness for Improved Crewmember Comfort and Load Distribution

The current design of the International Space Station (ISS) Treadmill Harness has been reported to cause pain and discomfort to crewmembers during exercise. The Harness Station Development Test Objective (SDTO) provided participating crewmembers (n = 6) with a new harness design, the "Glenn Harness," to evaluate for comfort and loading as compared to the current Treadmill Harness. A novel suite of load-sensing instrumentation was developed to noninvasively measure load distribution and provided a first-ever quantification of actual dynamic loads during treadmill exercise. In addition, crew debriefs provided feedback on harness preference and overall impressions. Conclusions: Post-flight analysis in returned Glenn Harnesses (n = 3) showed minimal wear and tear. Four of the six subjects found the Glenn Harness to be more comfortable in this on-orbit, side-by-side comparison as measured by the crew comfort questionnaire and crew debriefs. Specific areas for improvement have been identified, and forward recommendations will be provided to the Human Research Program. The protocol developed for the SDTO provided valuable insight into crew comfort issues, design improvements, and loading preferences for exercise harnessing, which lays the groundwork for better harnessing systems and training protocols

Advanced Exercise Concepts for Exploration

No abstract availabl

Computational Modeling Using OpenSim to Simulate a Squat Exercise Motion

Long duration space travel to destinations such as Mars or an asteroid will expose astronauts to extended periods of reduced gravity. Astronauts will use an exercise regime for the duration of the space flight to minimize the loss of bone density, muscle mass and aerobic capacity that occurs during exposure to a reduced gravity environment. Since the area available in the spacecraft for an exercise device is limited and gravity is not present to aid loading, compact resistance exercise device prototypes are being developed. Since it is difficult to rigorously test these proposed devices in space flight, computational modeling provides an estimation of the muscle forces, joint torques and joint loads during exercise to gain insight on the efficacy to protect the musculoskeletal health of astronauts

Parabolic Flight Investigation for Advanced Exercise Concept Hardware Hybrid Ultimate Lifting Kit (HULK)

Long-duration space flight poses many hazards to the health of the crew. Among those hazards is the physiological deconditioning of the musculoskeletal and cardiovascular systems due to prolonged exposure to microgravity. To combat this erosion of physical condition space flight may take on the crew, the Human Research Program (HRP) is charged with developing Advanced Exercise Concepts to maintain astronaut health and fitness during long-term missions, while keeping device mass, power, and volume to a minimum. The goal of this effort is to preserve the physical capability of the crew to perform mission critical tasks in transit and during planetary surface operations. The HULK is a pneumatic-based exercise system, which provides both resistive and aerobic modes to protect against human deconditioning in microgravity. Its design targeted the International Space Station (ISS) Advanced Resistive Exercise Device (ARED) high level performance characteristics and provides up to 600 foot pounds resitive loading with the capability to allow for eccentric to concentric (E:C) ratios of higher than 1:1 through a DC motor assist component. The device's rowing mode allows for high cadence aerobic activity. The HULK parabolic flight campaign, conducted through the NASA Flight Opportunities Program at Ellington Field, resulted in the creation of device specific data sets including low fidelity motion capture, accelerometry and both inline and ground reaction forces. These data provide a critical link in understanding how to vibration isolate the device in both ISS and space transit applications. Secondarily, the study of human exercise and associated body kinematics in microgravity allows for more complete understanding of human to machine interface designs to allow for maximum functionality of the device in microgravity

Computational Modeling of Space Physiology for Informing Spaceflight Countermeasure Design and Predictions of Efficacy

MOTIVATION: Spaceflight countermeasures mitigate the harmful effects of the space environment on astronaut health and performance. Exercise has historically been used as a countermeasure to physical deconditioning, and additional countermeasures including lower body negative pressure, blood flow occlusion and artificial gravity are being researched as countermeasures to spaceflight-induced fluid shifts. The NASA Digital Astronaut Project uses computational models of physiological systems to inform countermeasure design and to predict countermeasure efficacy.OVERVIEW: Computational modeling supports the development of the exercise devices that will be flown on NASAs new exploration crew vehicles. Biomechanical modeling is used to inform design requirements to ensure that exercises can be properly performed within the volume allocated for exercise and to determine whether the limited mass, volume and power requirements of the devices will affect biomechanical outcomes. Models of muscle atrophy and bone remodeling can predict device efficacy for protecting musculoskeletal health during long-duration missions. A lumped-parameter whole-body model of the fluids within the body, which includes the blood within the cardiovascular system, the cerebral spinal fluid, interstitial fluid and lymphatic system fluid, estimates compartmental changes in pressure and volume due to gravitational changes. These models simulate fluid shift countermeasure effects and predict the associated changes in tissue strain in areas of physiological interest to aid in predicting countermeasure effectiveness. SIGNIFICANCE: Development and testing of spaceflight countermeasure prototypes are resource-intensive efforts. Computational modeling can supplement this process by performing simulations that reduce the amount of necessary experimental testing. Outcomes of the simulations are often important for the definition of design requirements and the identification of factors essential in ensuring countermeasure efficacy

Entre o Caribe e a Amazônia: haitianos em Manaus e os desafios da inserção sociocultural

RESUMO A chegada dos primeiros haitianos à cidade de Manaus, a partir de 2010, foi interpretada inicialmente como um fenômeno passageiro e que a cidade seria apenas um local de passagem para a maioria deles, já que o Brasil das "oportunidades" do qual eles tinham ouvido falar ficava mais a sudeste e sul. Essa percepção inicial parece ter se confirmada em parte, pois, segundo a Pastoral do Migrante, dos mais de oito mil haitianos que haviam passado por Manaus, cerca de mil ainda permanecem na cidade. Dentre os que escolheram permanecer, importa indagar quais seriam as razões dessa "escolha" e como tem sido o processo de inserção sociocultural. Considerando o curto espaço de tempo da presença haitiana em Manaus, e os desafios socioeconômicos enfrentados por esses imigrantes, este artigo levanta algumas hipóteses sobre as possibilidades de trocas culturais entre haitianos e brasileiros, a partir dos universos religioso e musical

Trabalho precário e precarização institucional nos Estados Unidos Precarious work and the institutional precarization in the United States

Este artigo analisa as bases institucionais do trabalho precário nos Estados Unidos através de um duplo processo de precarização: da relação contratual tradicional e, dada a fragmentação do quadro institucional, a inadaptação da lei trabalhista dos Estados Unidos. O texto procura enfatizar a importância do estatuto do trabalhador - a relação contratual de emprego - para o acesso do mesmo aos direitos e benefícios sociais básicos. Os efeitos da recente crise econômica e a resposta das políticas públicas são discutidos na conclusão.<br>We analyze the institutional underpinnings of precarious work in the United States through a double process of precarization: of the traditional contractual relationship and given the fragmented institutional framework and the inadaptation of U.S. labor law. The importance of the employee status - the contractual employment relationship - for access to social rights and basic benefits is emphasized. Effects of the recent economic crisis and public policy response are discussed in conclusion