No abstract

The purpose of this study was to determine biomechanical factors that may influence golf swing power generation. Three-dimensional kinematics and kinetics were examined in 10 professional and 5 amateur male golfers. Upper-torso rotation, pelvic rotation, X-factor (relative hip-shoulder rotation), O-factor (pelvic obliquity), S-factor (shoulder obliquity), and normalized free moment were assessed in relation to clubhead speed at impact (CSI). Among professional golfers, results revealed that peak free moment per kilogram, peak X-factor, and peak S-factor were highly consistent, with coefficients of variation of 6.8%, 7.4%, and 8.4%, respectively. Downswing was initiated by reversal of pelvic rotation, followed by reversal of upper-torso rotation. Peak X-factor preceded peak free moment in all swings for all golfers, and occurred during initial downswing. Peak free moment per kilogram, X-factor at impact, peak X-factor, and peak upper-torso rotation were highly correlated to CSI (median correlation coefficients of 0.943, 0.943, 0.900, and 0.900, respectively). Benchmark curves revealed kinematic and kinetic temporal and spatial differences of amateurs compared with professional golfers. For amateurs, the number of factors that fell outside 1–2 standard deviations of professional means increased with handicap. This study identified biomechanical factors highly correlated to golf swing power generation and may provide a basis for strategic training and injury prevention.

In PTS, a bullseye sign on MRI can accurately localize HGCs, a previously unreported finding. Causes of HGCs and the bullseye sign are unknown. Muscle Nerve 56: 99-106, 2017.

No abstract

No abstract

No abstract

The main contribution of the book is the framework it provides. It includes a special emphasis on software design. It also provides a practically oriented, theory-based process for understanding, controlling, and designing for the interaction between the human and technology. The book contains an overview of system development, the design process, design methods and practice, information resources, software design and the user.The authors state that their fascination with design is derived in part from its complexity. In the preface they state that there are ". . . no simple answers" to the questions they will raise. They have certainly, by design, left the reader with more questions than answers. They conclude by acknowledging that obviously there is much need for additional research, and that other researchers will have other questions to ask. The book gives an excellent, yet cynical, overview of the current state of our understanding of design as a process and highlights the human factors specialists' current difficulty in conveying, quantitatively, the implications of their so far limited understanding of the human operator performance and response in a technological system. The book is a bit of a catharsis on the way to development of an outline of a behavioral theory of design.However, it is efficiently done. The authors review ideas from key research in the behavioral aspects of hardware and software systems development, and in doing so have clarified terms from the literature that should serve readers both inside and outside the human factors and ergonomics (HFE) discipline well. The most refreshing and enlightening part is chapter 4 on design practice, in which the authors report the results of a survey of design professionals (most of whom have an HFE background). Many of the authors' initial beliefs are refuted by the results of the survey, which suggest that "Obviously we still have a way to go in terms of complete acceptance [of HFE in design practice], but the situation seems not to be as bad as was described in earlier writings."An earlier portion of the book focuses on concerns that human factors research has not been broadly applied in design of technical systems. The authors also suggest that in order to develop a useful HFE database (p. 134), a great deal of additional research would be needed, and on the one hand suggest that enthusiasm seems to be lacking in the human factors community for developing such a database. However, in fairness to the discipline (p. 135), the authors acknowledge that if sufficient funding were available, researchers

This is continuation of studies of the history and characteristics of human factors ergonomics (HFE). Earlier studies had analyzed the annual meeting programs of the Human Factors Society from 1959 to 1970 and empirical papers (those that tested subjects) that were published in Human Factors and in the Proceedings of the annual meetings of the Society. Every discipline has a history, and it is important to examine that history in terms of what its professionals publish and consider, because this enables one to see how and in which direction the discipline is moving. A historical analysis serves as a sort of feedback, if one thinks of the discipline as a special type of conceptual system.