Acute cardiovascular responses to interval exercise: A systematic review and meta-analysis

ABSTRACT

Interval exercise training is increasingly recommended to improve health and fitness; however, it is not known if cardiovascular risk is different from continuous exercise protocols. This systematic review with meta-analyses assessed the effect of a single bout of interval exercise on cardiovascular responses that indicate risk of cardiac fibrillation and infarction compared to continuous exercise. Electronic databases Medline, CINAHL, Embase, Scopus and Cochrane were searched. Key inclusion criteria were: (1) intervals of the same intensity and duration followed by a recovery period and (2) reporting at least one of blood pressure, heart rate variability, arterial stiffness or function. Cochrane Risk of Bias tool and GRADE approach were used. Meta-analyses found that systolic blood pressure responses to interval exercise did not differ from responses to continuous exercise immediately (MD 8 mmHg [95% CI ?32, 47], p = 0.71) or at 60 min following exercise (MD 0 mmHg [95% CI ?2, 1], p = 0.79). However, reductions in diastolic blood pressure and flow-mediated dilation with interval exercise were observed 10–15 min post-exercise. The available evidence indicates that interval exercise does not convey higher cardiovascular risk than continuous exercise. Further investigation is required to establish the safety of interval exercise for clinical populations.     

Validation of the Microsoft Kinect® camera system for measurement of lower extremity jump landing and squatting kinematics

Cost effective, quantifiable assessment of lower extremity movement represents potential improvement over standard tools for evaluation of injury risk. Ten healthy participants completed three trials of a drop jump, overhead squat, and single leg squat task. Peak hip and knee kinematics were assessed using an 8 camera BTS Smart 7000DX motion analysis system and the Microsoft Kinect® camera system. The agreement and consistency between both uncorrected and correct Kinect kinematic variables and the BTS camera system were assessed using interclass correlations coefficients. Peak sagittal plane kinematics measured using the Microsoft Kinect® camera system explained a significant amount of variance [Range_hip = 43.5–62.8%; Range_knee = 67.5–89.6%] in peak kinematics measured using the BTS camera system. Across tasks, peak knee flexion angle and peak hip flexion were found to be consistent and in agreement when the Microsoft Kinect® camera system was directly compared to the BTS camera system but these values were improved following application of a corrective factor. The Microsoft Kinect® may not be an appropriate surrogate for traditional motion analysis technology, but it may have potential applications as a real-time feedback tool in pathological or high injury risk populations.     

The Development of the Olympic Narrative in Chinese Elite Sport Discourse from Its First Successful Olympic Bid to the Post-Beijing Games Era

Abstract

As a phenomenon exogenous to China, the Olympics have been proactively interpreted in the local context since China’s entry (and subsequent re-entry in 1984) into the Olympic movement. With China’s increasing involvement in promoting three bids to host the Olympic Games, two of which were successful, respectively, in 2001 and 2015, the nature of the discourse of key stakeholders in relation to Chinese elite sport has both reflected and reshaped the meaning of the Games to Chinese elite sport. This paper examines the discursive construction process of the Olympics in the Chinese elite sport system by key stakeholders through analyzing statements of political figures on sport and Olympic phenomena, Chinese elite sport policy documents, and the commentaries of leading Chinese sport academics. The analysis of discourse highlights two main features in the construction of the Games in official accounts during the period under investigation. The development of these two themes reflects the nature of the Chinese Olympic discourse, manifests the political power over the interpretation of the Olympics in Chinese context, and continues to characterize the on-going major themes in Chinese elite sport policy.     

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.     

‘Muscles for Motherhood’: A Genealogical Analysis of Medicalized Ways of Knowing Female Footballers in New Zealand, 1921 and 1973–1975

ABSTRACT

Michel Foucault argued that females gradually became integrated into the sphere of medical practices through a process which he termed as a ‘hysterization of women’s bodies’ (Foucault, The History of Sexuality, Volume One: An Introduction, New York: Pantheon Books, 1978, 104). In this article, we draw on Foucault to examine how women’s bodies, exercise and motherhood impacted on the historical development of female football in New Zealand within two time periods (1921 and 1973–1975). Employing his genealogical framework, we analyze newspaper reports, historical documents and conducted in-depth interviews to demonstrate how medical/scientific discourses both constrained and enabled the participation of women in football. We conclude that while medical knowledge was used to publicly disqualify the legitimacy of the female footballer in 1921, and hence her abrupt disappearance from the sporting realm, the absence of such medical knowledge in the early 1970s, combined with societal changes associated with second wave feminism, paved the way for the eventual ‘normalization’ of female football in New Zealand.     

Dial the Difference—How and Why BBC Local Radio and Independent Local Radio Developed Different News Services

This article is principally concerned with how and why these 2 types of radio news developed. It discusses the culture, ethos and practices of the 2 services and, in particular, if and how each was influenced by the other. Much of the article is concerned about how the new commercial stations developed practices and styles that were consciously different from, and in some cases in direct opposition to, those at the BBC, both nationally and locally. The article argues that it was the BBC which adopted and integrated commercial radio’s style and practices, rather than, as is often supposed, the other way around.     

Spelling development in 6–11‐year‐old Greek‐speaking Cypriot children

The aim of the present study was to examine the spelling development of Greek‐speaking children in the early school grades. Although Greek orthography is regular for reading, it is much less transparent as far as spelling is concerned. Spelling development was investigated using a word spelling task designed to explore the effects of word length, familiarity and spelling regularity. One hundred and fifty normally developing primary school children living in Cyprus took part in the study. Results suggest that the children employed both phonological and lexical strategies in spelling Greek words. Results indicated that sub‐lexical procedures were more marked for younger children, whereas lexical processing was employed more widely by older children. The findings are interpreted in terms of stage developmental models.     

The average IQ of sub-Saharan Africans assessed by the Progressive Matrices: A reply to Wicherts,Dolan, Carlson & van der Maas

Wicherts, Dolan, Carlson & van der Maas (WDCM) (2010) contend that the average IQ in sub-Saharan Africa is about 76 in relation to a British mean of 100 and sd of 15. This result is achieved by including many studies of unrepresentative elite samples. Studies of acceptably representative samples indicate a sub-Saharan Africa IQ of approximately 66.     

A medical journal's beta site: experimentation at NEJM

When continuous development becomes the norm on the social web, finding a way to put forward new development ideas to your audience and get their feedback at an early stage is the natural result. This article discusses how one major medical journal created a ‘beta’ site to support new online development and gather user feedback, speeding development initiatives and creating intrinsic value in the experimental environment. The goals of the site, organization of the teams, and practical and brand benefits are discussed.