Different metabolic responses during incremental exercise assessed by localized 31P MRS in sprint and endurance athletes and untrained individuals

Until recently, assessment of muscle metabolism was only possible by invasive sampling. 31P magnetic resonance spectroscopy ( 31P MRS) offers a way to study muscle metabolism non-invasively. The aim of the present study was to use spatially-resolved 31P MRS to assess the metabolism of the quadriceps muscle in sprint-trained, endurance-trained and untrained individuals during exercise and recovery. 5 sprint-trained (STA), 5 endurance-trained (ETA) and 7 untrained individuals (UTI) completed one unlocalized 31P MRS session to measure phosphocreatine (PCr) recovery, and a second session in which spatially-resolved 31P MR spectra were obtained. PCr recovery time constant (τ) was significantly longer in STA (50±17 s) and UTI (41±9 s) than in ETA (30±4 s), (P\u3c0.05). PCr changes during exercise differed between the groups, but were uniform across the different components of the quadriceps within each group. pH during recovery was higher for the ETA than for the UTI (P\u3c0.05) and also higher than for the STA (P\u3c0.01). Muscle volume was greater in STA than in UTI (P\u3c0.05) but not different from ETA. Dynamic 31P MRS revealed considerable differences among endurance and sprint athletes and untrained people. This non-invasive method offers a way to quantify differences between individual muscles and muscle components in athletes compared to untrained individuals. 2013 Georg Thieme Verlag KG Stuttgart.New York

How to Do Things with Words and Texts: Literature and Rewriting as Performance in Lloyd Jones' Mister Pip

Ever since J. L. Austin drew attention to the distinction between constatives and performatives in language, speech-act theory has provided significant insights into literary studies. Exploring the performative quality of language as it is employed in literature has introduced new perspectives on issues like the relationship between literary and non-literary language, the nature and ontological status of literary discourse, and the power and potential of literature to influence events. Motivated by such possibilities of interpretation and analysis, this essay approaches New Zealand author Lloyd Jones' recent award-winning novel Mister Pip (2006) from the perspective of studies in performative language. By exploring the way Jones' novel presents literature and rewriting as speech acts, the essay emphasizes the power of the literary text to refer to "reality'' and transform it seriously in both positive and negative ways. In doing so, the essay also aims to demonstrate how the diversity of ways in which speech-act theory has been approached by literary scholars is an indication of the wide-ranging possibilities the theory affords for literary studies