Sex differences in static strength and fatigability in three different muscle groups

Maximal voluntary static muscle force production was assessed both in strength trials and during 2-min contractions by three muscle groups (right-hand finger flexors [RHF], right-leg extensors [RLE], and both leg extensors [BLE]) in young males (n = 13) and females (n = 14). There was a significant difference (p less than .01) between males and females for RHF strength and BLE strength but no significant difference between sexes for RLE strength. During the 2-min task, impulse (force x time) declined significantly (p less than .001) and there was a significant difference (p less than .001) between muscle groups, but there was no difference between sexes. There was a significant (p less than .05) sex x time interaction for the impulse values indicating that the fatigability was greater in males than females.     

Rethinking fat as a fuel for endurance exercise

Abstract

A key element contributing to deteriorating exercise capacity during physically demanding sport appears to be reduced carbohydrate availability coupled with an inability to effectively utilize alternative lipid fuel sources. Paradoxically, cognitive and physical decline associated with glycogen depletion occurs in the presence of an over-abundance of fuel stored as body fat that the athlete is apparently unable to access effectively. Current fuelling tactics that emphasize high-carbohydrate intakes before and during exercise inhibit fat utilization. The most efficient approach to accelerate the body’s ability to oxidize fat is to lower dietary carbohydrate intake to a level that results in nutritional ketosis (i.e., circulating ketone levels >0.5 mmol/L) while increasing fat intake for a period of several weeks. The coordinated set of metabolic adaptations that ensures proper interorgan fuel supply in the face of low-carbohydrate availability is referred to as keto-adaptation. Beyond simply providing a stable source of fuel for the brain, the major circulating ketone body, beta-hydroxybutyrate, has recently been shown to act as a signalling molecule capable of altering gene expression, eliciting complementary effects of keto-adaptation that could extend human physical and mental performance beyond current expectation. In this paper, we review these new findings and propose that the shift to fatty acids and ketones as primary fuels when dietary carbohydrate is restricted could be of benefit for some athletes.     

加拿大安大略省健康与体育课程标准中德育内容的分析与启示

通过对加拿大安大略省健康与体育课程标准中的德育内容分析和研究发现,安大略省的德育深深地渗透在健康与体育课程内,其特点主要包括：其一,安大略省的健康与体育课程中德育内容要求是发展性的,即不同年级阶段,德育内容的要求重点不一样。其二,安大略省健康与体育课程的德育内容与学生的生活结合紧密,且紧紧融入在学生的学习和生活中。其三,安大略省健康和体育课程中的德育内容要求主要是通过学生“doing”的方式,让学生学习道德品质。其四,安大略省健康与体育课程中的德育内容要求从学校拓展到家庭、社区乃至整个社会,而不只是禁锢在班级内。其五,安大略省健康与体育课程强调培养学生的思考力和判断力。安大略省的健康与体育课程标准中的德育渗透对我国体育与健康课程教育教学中的德育教育具有重要的启示。     

Rationalizing Sociality: An Unfinished Script for Socialbots

This article takes the concept and some of the existing applications of socialbots—software robots that operate on social networking sites and present themselves as human users—as an occasion to trace the evolution of online sociality. The argument mobilizes theories of social rationalization from Max Weber to contemporary critical theory to demonstrate that the appearance of automated profiles (socialbots) on social networking platforms can be seen as a logical step in the progressive enclosure of online social interaction in standardized, simplified, and trivialized forms, frames, and gestures. Critical questions concerning what the growth of robo-sociality may mean for individual users and the online public sphere are posed with a view to charting the directions for a needed public debate.     

The emergence of a knowledge-based theory of internationalisation

This paper charts the development of the knowledge-based theory of internationalisation, driven particularly by early research at the University of Uppsala, led by Sune Carlson. Information and knowledge, allied with an interest in the associated effect on risk and uncertainty, were components of a process perspective. Its essence was a focus on the restraining effects of a lack of knowledge as decision-makers contemplated international market entry or expansion requiring a commitment of resources in various forms, in different types of foreign operations (such as exporting, licensing and foreign direct investment). Lack of knowledge of a prospective foreign market (of its characteristics, culture, ways of doing business) was seen to create uncertainty so that firm decision-makers would be less prepared to commit resources. This situation was bound to change as a firm conducted operations in the foreign market and acquired experiential knowledge (learning by doing), which made the foreign market less of a mystery, in the process lowering uncertainty. As the learning process unfolded, and expanded opportunities were perceived, at some stage the firm might be prepared to undertake additional commitments to the foreign market. Empirical research at Uppsala, and in Finland, had shown a pattern of gradual expansion of foreign commitments by internationalising firms. In terms of theoretical development, a key step was relaxation of the assumption of perfect knowledge used in economics (not without critique), noted by Don Lamberton in 1974. Following the development of internationalisation theory in the 1970s, there was a range of extensions to the basic theory, such as the role of networks, the nature of inward–outward connections, and the need for knowledge to pass over language hurdles in the process of international transmission – within and outside the firm. In one sense, the internationalisation of companies was a perfect research site for an exploration of the role of information and knowledge in firm behaviour, given the additional exigencies of the diverse and demanding information environment that is the international arena.