76 research outputs found

    Program to study optimal protocol for cardiovascular and muscular efficiency

    Get PDF
    Two possible ways to minimize the effects of deconditioning in space are; To achieve a very high level of conditioning immediately prior to flight, and to provide a regimen in the capsule which will maintain a moderate degree of fitness. It was determined that running and riding a bicycle ergometer at comparable heart rates produced similar gains in physical fitness variables. It was found that subjects who exercised at a 180 heart rate made greater gains in physical fitness than did those exercising at a 140 or 160 heart rate. When the length of the workout was varied, subjects exercising sixty minutes per day made greater gains than those exercising twenty or forty minutes per day. Subjects who discontinued training slowly deconditioned, but a moderate level of fitness could be maintained by exercising at a pulse rate of 160 beats per minute for twenty minute periods three times a week. Subjects who overtrained twice daily to near exhaustion increased in fitness

    Program to study optimal protocol for cardiovascular and muscular efficiency

    Get PDF
    Training programs necessary for the development of optimal strength during prolonged manned space flight were examined, and exercises performed on the Super Mini Gym Skylab 2 were compared with similar exercises on the Universal Gym and calisthenics. Cardiopulmonary gains were found negligible but all training groups exhibited good gains in strength

    Study of optimal training protocols and devices for developing and maintaining physical fitness in females prior to and during space flight

    Get PDF
    Pedalling a bicycle at least ten minutes a day at 85% of maximum pulse rate, three days a week for ten weeks will produce moderate increases in overall strength and physical work capacity in college-age females. The longer the training session, up to thirty minutes per session, the greater are the increases in physical work capacity that result when college-age females are trained three days a week for ten weeks at 85% of their maximum heart rate

    Isokinetic exercise: A review of the literature

    Get PDF
    Isokinetic muscle training has all the advantages of isometrics and isotonics while minimizing their deficiencies. By holding the speed of movement constant throughout the full range of motion, isokinetic training devices respond with increased resistance rather than acceleration when the power output of the muscle is increased. Isokinetic training is superior to isometric and isotonic training with respect to increases in strength, specificity of training, desirable changes in motor performance tasks, lack of muscle soreness, and decreases in relative body fat

    How does viscosity contrast influence phase mixing and strain localization?

    Get PDF
    Author Posting. © American Geophysical Union, 2020. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Solid Earth 125 (2020): e2020JB020323, doi: 10.1029/2020JB020323.Ultramylonites—intensely deformed rocks with fine grain sizes and well‐mixed mineral phases—are thought to be a key component of Earth‐like plate tectonics, because coupled phase mixing and grain boundary pinning enable rocks to deform by grain‐size‐sensitive, self‐softening creep mechanisms over long geologic timescales. In isoviscous two‐phase composites, “geometric” phase mixing occurs via the sequential formation, attenuation (stretching), and disaggregation of compositional layering. However, the effects of viscosity contrast on the mechanisms and timescales for geometric mixing are poorly understood. Here, we describe a series of high‐strain torsion experiments on nonisoviscous calcite‐fluorite composites (viscosity contrast, ηca/ηfl ≈ 200) at 500°C, 0.75 GPa confining pressure, and 10−6–10−4 s−1 shear strain rate. At low to intermediate shear strains (Îł ≀ 10), polycrystalline domains of the individual phases become sheared and form compositional layering. As layering develops, strain localizes into the weaker phase, fluorite. Strain partitioning impedes mixing by reducing the rate at which the stronger (calcite) layers deform, attenuate, and disaggregate. Even at very large shear strains (Îł ≄ 50), grain‐scale mixing is limited, and thick compositional layers are preserved. Our experiments (1) demonstrate that viscosity contrasts impede mechanical phase mixing and (2) highlight the relative inefficiency of mechanical mixing. Nevertheless, by employing laboratory flow laws, we show that “ideal” conditions for mechanical phase mixing may be found in the wet middle to lower continental crust and in the dry mantle lithosphere, where quartz‐feldspar and olivine‐pyroxene viscosity contrasts are minimized, respectively.This work was funded through a National Science Foundation grant (EAR‐1352306) awarded to P. S., with additional support for A. J. C. provided by the McDonnell Center for the Space Sciences (Washington University in St. Louis), the J. Lamar Worzel Assistant Scientist Fund (WHOI), and the Penzance Endowed Fund in Support of Assistant Scientists (WHOI). Partial support for electron microscopy was provided by the Institute of Materials Science and Engineering (Washington University in St. Louis).2021-02-0

    Differential activation of nerve fibers with magnetic stimulation in humans

    Get PDF
    BACKGROUND: Earlier observations in our lab had indicated that large, time-varying magnetic fields could elicit action potentials that travel in only one direction in at least some of the myelinated axons in peripheral nerves. The objective of this study was to collect quantitative evidence for magnetically induced unidirectional action potentials in peripheral nerves of human subjects. A magnetic coil was maneuvered to a location on the upper arm where physical effects consistent with the creation of unidirectional action potentials were observed. Electromyographic (EMG) and somatosensory evoked potential (SEP) recordings were then made from a total of 20 subjects during stimulation with the magnetic coil. RESULTS: The relative amplitudes of the EMG and SEP signals changed oppositely when the current direction in the magnetic coil was reversed. This effect was consistent with current direction in the coil relative to the arm for all subjects. CONCLUSION: A differential evocation of motor and sensory fibers was demonstrated and indicates that it may be possible to induce unidirectional action potentials in myelinated peripheral nerve fibers with magnetic stimulation

    The Continuing Threshold Test for Free Exercise Claims

    Full text link
    When a claimant challenges some governmental law or action under the Free Exercise Clause of the First Amendment, courts have long required the claimant to make out a prima facie case that the government has burdened the exercise of the claimant\u27s sincerely held religious beliefs. This requirement has been referred to as the threshold test for free exercise claims, since claimants must make this showing as a threshold matter before courts will proceed to evaluate the burden and the governmental interest at stake under some standard of scrutiny. This Article argues that although the Supreme Court of the United States has recently adopted a more deferential standard of scrutiny for many types of free exercise claims, the Court has never signaled dissatisfaction with the threshold test itself, and indeed could not abandon the test without being unfaithful to the text of the Free Exercise Clause. Moreover, this Article proposes that the Court\u27s most recent free exercise case, Locke v. Davey, can be understood as a rejection of the claimant\u27s challenge for failure to satisfy the threshold test. So understood, Davey signals little change in free exercise law and poses no new obstacle to claimants in future free exercise challenges involving governmental funding programs of various sorts

    Implementation of the Tobacco Tactics intervention versus usual care in Trinity Health community hospitals

    Get PDF
    Abstract Background Guided by the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) implementation framework, a National Institutes of Health-sponsored study compared the nurse-administered Tobacco Tactics intervention to usual care. A prior paper describes the effectiveness of the Tobacco Tactics intervention. This subsequent paper provides data describing the remaining constructs of the RE-AIM framework. Methods This pragmatic study used a mixed methods, quasi-experimental design in five Michigan community hospitals of which three received the nurse-administered Tobacco Tactics intervention and two received usual care. Nurses and patients were surveyed pre- and post-intervention. Measures included reach (patient participation rates, characteristics, and receipt of services), adoption (nurse participation rates and characteristics), implementation (pre-to post-training changes in nurses' attitudes, delivery of services, barriers to implementation, opinions about training, documentation of services, and numbers of volunteer follow-up phone calls), and maintenance (continuation of the intervention once the study ended). Results Reach: Patient participation rates were 71.5 %. Compared to no change in the control sites, there were significant pre- to post-intervention increases in self-reported receipt of print materials in the intervention hospitals (n = 1370, p < 0.001). Adoption: In the intervention hospitals, all targeted units and several non-targeted units participated; 76.0 % (n = 1028) of targeted nurses and 317 additional staff participated in the training, and 92.4 % were extremely or somewhat satisfied with the training. Implementation: Nurses in the intervention hospitals reported increases in providing advice to quit, counseling, medications, handouts, and DVD (all p < 0.05) and reported decreased barriers to implementing smoking cessation services (p < 0.001). Qualitative comments were very positive (“user friendly,” “streamlined,” or “saves time”), although problems with showing patients the DVD and charting in the electronic medical record were noted. Maintenance: Nurses continued to provide the intervention after the study ended. Conclusions Given that nurses represent the largest group of front-line providers, this intervention, which meets Joint Commission guidelines for treating inpatient smokers, has the potential to have a wide reach and to decrease smoking, morbidity, and mortality among inpatient smokers. As we move toward more population-based interventions, the RE-AIM framework is a valuable guide for implementation. Trial registration ClinicalTrials.gov, NCT0130921
    • 

    corecore