Reviewing the Variability-Overuse Injury Hypothesis: Does Movement Variability Relate to Landing Injuries?

Purpose: Overuse injuries are common in sport, but complete understanding of injury risk factors remains incomplete. Although biomechanical studies frequently examine musculoskeletal injury mechanisms, human movement variability studies aim to better understand neuromotor functioning, with proposed connections between overuse injury mechanisms and changes in motor variability. Method: In a narrative review, we discuss the variability-overuse injury hypothesis, which suggests repeated load application leads to mechanical tissue breakdown and subsequent injury when exceeding the rate of physiological adaptation. Due to the multidisciplinary nature of this hypothesis, we incorporate concepts from motor control, neurophysiology, biomechanics, as well as research design and data analysis. We therefore summarize multiple perspectives while proposing theoretical relationships between movement variability and lower extremity overuse injuries. Results: Experimental data are presented and summarized from published experiments examining interactions between experimental task demands and movement variability in the context of drop landing movements, along with comparisons to previous movement variability studies. Conclusion: We provide a conceptual framework for sports medicine researchers interested in predicting and preventing sports injuries. Under performance conditions with greater task demands, we predict reduced trial-to-trial movement variability that could increase the likelihood of overuse injuries.     

Transforming in the visiting assistant professor role: collaborative self-study research in physical education teacher education

Transitioning into faculty roles can be a challenging experience. Responsibilities related to teaching, research, and service can be difficult to balance, and mismatch between personal preferences for work focus and instructional expectations can be problematic. This is particularly true of visiting assistant professors who want to work toward tenure-track positions, but whose current job focus is on teaching. Through transformative learning theory and employing the methodologies of self-study, we sought to understand the experiences of Kevin, the second author and a first-year visiting assistant professor. We draw data from Kevin's reflective journal and discussions between Kevin and his critical friend, Jim. Themes included (a) becoming an academic, (b) a hard-wired disposition toward work, and (c) influence of the VAP on emotional and personal health. Results are discussed through the lens of transformative learning theory and focus on Kevin's growth during his year as a visiting assistant professor.     

Considerations for the use of functional principal components analysis in sports biomechanics: examples from on-water rowing

The proliferation of new biomechanical technology in laboratory and field settings facilitates the capture of data-sets consisting of complex time-series. An understanding of the appropriate statistical approaches for analysing and interpreting these data-sets is required and the functional data analysis (FDA) family of statistical techniques has emerged in the biomechanical literature. Given the use of FDA is currently in its infancy with biomechanical data, this paper will form the first of a two part series aiming to address practical issues surrounding the application of FDA techniques in biomechanics. This work focuses on functional principal components analysis (fPCA), which is explored using existing literature and sample data from an on-water rowing database. In particular methodological considerations for the implementation of fPCA such as temporal normalisation of data, removal of unwanted forms of variation in a data-set and documented methods for preserving the original temporal properties within a set of curves are explored in detail as a part of this review. Limitations and strengths of the technique are outlined and recommendations are provided to encourage the appropriate use of fPCA within the field of applied sports biomechanics.     

Accessions: researching,designing higher education

This brief viewpoint piece depicts educational (dis)engagements apparent in researching and (re)designing higher education in and through Accessions. Accessions, a collaborative research-design project, probed at how cultures, climates and conditions of higher education may be reproducing or reshaping social inequalities and divisions. Here, questions are asked about how these might be challenged within and potentially beyond the specific locale of one university campus. This research-design project hopes to enable a critical perspective on issues of ‘participation’, ‘impact’, ‘engagement’ and ‘internationalisation’, where regulations and measures may be resisted and disrupted.     

Numerical modelling of rowing blade hydrodynamics

The highly unsteady flow around a rowing blade in motion is examined using a three-dimensional computational fluid dynamics (CFD) model which accounts for the interaction of the blade with the free surface of the water. The model is validated using previous experimental results for quarter-scale blades held stationary near the surface in a water flume. Steady-state drag and lift coefficients from the quarter-scale blade flume simulation are compared to those from a simulation of the more realistic case of a full-scale blade in open water. The model is then modified to accommodate blade motion by simulating the unsteady motion of the rowing shell moving through the water, and the sweep of the oar blade with respect to the shell. Qualitatively, the motion of the free surface around the blade during a stroke shows a realistic agreement with the actual deformation encountered during rowing. Drag and lift coefficients calculated for the blade during a stroke show that the transient hydrodynamic behaviour of the blade in motion differs substantially from the stationary case.