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.     

Data assemblages,sentient schools and digitised health and physical education (response to Gard)

Michael Gard raises some important issues in his opinion piece on digitised health and physical education (HPE) in the school setting. His piece represents the beginning of a more critical approach to the instrumental and solutionist perspectives that are currently offered on digitised HPE. Few commentators in education, health promotion or sports studies have begun to realise the extent to which digital data surveillance and analytics are now encroaching into many social institutions and settings and the ways in which actors and agencies in the digital knowledge economy are appropriating these data. Identifying what is happening and the implications for the concepts of selfhood, body and social relations, not to mention the more specific issues of privacy and the commercialisation and exploitation of personal data, requires much greater attention than these issues have previously received in the critical social research literature. While Gard has begun to do this in his article, there is much more to discuss. In this response, I present some discussion that seeks to provide a complementary commentary on the broader context in which digitised HPE is developing and manifesting. Whether or not one takes a position that is techno-utopian, dystopian or somewhere in between, I would argue that to fully understand the social, cultural and political resonances of digitised HPE, such contextualising is vital.     

The influence of live- vs. video-model presentation on the early acquisition of a new complex coordination

Background: Demonstration is a widely used method in sports teaching and coaching, based on the assumption that it is more beneficial than verbal instructions or trial-and-error methods for skill acquisition. Although in teaching/coaching situations, the demonstration is usually carried out in front of the learners, in a research context, it is most often presented via a video. However, a direct comparison between these two types of model has rarely been undertaken in a motor context.

Purpose: In this study, we aimed to compare the effectiveness of the observation of a live and a videomodel for the early acquisition of a complex judo movement.

Research Design: Participants observed either a live or a videomodel executing the task. After observation, they practised for three minutes taking five trials and then performed it for analysis. This procedure was repeated three times. The form and technique of each participant's execution were evaluated using a technical score.

Main results: The results indicated a significant improvement in the task execution by the end of the practice session. However, this improvement occurred only for the video-model group between the second and third blocks of practice.

Conclusions: The video demonstration seems more effective than the live one for the early acquisition of a completely new complex coordination. This may be due to the simplification of the visual information in the former condition because of its two-dimensionality. This simplification may allow the observer to identify the more key elements that would guide him/her for the subsequent performance of the task.     

Development of a grinding-specific performance test set-up

Abstract

The aim of this study was to develop a performance test set-up for America's Cup grinders. The test set-up had to mimic the on-boat grinding activity and be capable of collecting data for analysis and evaluation of grinding performance. This study included a literature-based analysis of grinding demands and a test protocol developed to accommodate the necessary physiological loads. This study resulted in a test protocol consisting of 10 intervals of 20 revolutions each interspersed with active resting periods of 50 s. The 20 revolutions are a combination of both forward and backward grinding and an exponentially rising resistance. A custom-made grinding ergometer was developed with computer-controlled resistance and capable of collecting data during the test. The data collected can be used to find measures of grinding performance such as peak power, time to complete and the decline in repeated grinding performance.