Leg muscle recruitment in highly trained cyclists

In this study, we examined patterns of leg muscle recruitment and co-activation, and the relationship between muscle recruitment and cadence, in highly trained cyclists. Electromyographic (EMG) activity of the tibialis anterior, tibialis posterior, peroneus longus, gastrocnemius lateralis and soleus was recorded using intramuscular electrodes, at individual preferred cadence, 57.5, 77.5 and 92.5 rev . min(-1). The influence of electrode type and location on recorded EMG was also investigated using surface and dual intramuscular recordings. Muscle recruitment patterns varied from those previously reported, but there was little variation in muscle recruitment between these highly trained cyclists. The tibialis posterior, peroneus longus and soleus were recruited in a single, short burst of activity during the downstroke. The tibialis anterior and gastrocnemius lateralis were recruited in a biphasic and alternating manner. Contrary to existing hypotheses, our results indicate little co-activation between the tibialis posterior and peroneus longus. Peak EMG amplitude increased linearly with cadence and did not decrease at individual preferred cadence. There was little variation in patterns of muscle recruitment or co-activation with changes in cadence. Intramuscular electrode location had little influence on recorded EMG. There were significant differences between surface and intramuscular recordings from the tibialis anterior and gastrocnemius lateralis, which may explain differences between our findings and those of previous studies.     

Value creation in the engineering enterprise: an educational perspective

ABSTRACT

This position paper sets out to examine value creation in the engineering enterprise, a process that has mostly been associated with innovation and entrepreneurs. An analysis of the literature on engineering value creation in business studies, engineering and engineering education publications shows that there has been surprisingly little empirical study and thus the means by which most engineers contribute value is unclear in the literature. Analysis of published data and data from studies by the authors in engineering workplaces in Australia, South East Asia and Portugal suggests that the work performed by most engineers has little to do with innovation. Based on these data the authors identify 14 ways in which engineers create value. An important finding is that routine engineering performances by a majority of engineers, not associated with innovation or entrepreneurial activities, not only can be shown to create value, but also to protect accumulated value from inadvertent destruction. The paper outlines the educational implications of these findings and proposes measures that engineering educators can adopt to improve the understanding of engineering graduates about engineering value creation.     

Scaffolding group explanation and feedback with handheld technology: impact on students’ mathematics learning

Based on strong research literatures, we conjectured that social processing of feedback by cooperating in a small group setting—with social incentives to ask questions, give explanations and discuss disagreements—would increase learning. We compared group and individual feedback, using two technologies: (1) Technology-mediated, Peer-Assisted Learning (TechPALS), which uses wireless handheld technology to structure feedback in small groups as they solve fractions problems and (2) a popular desktop product, which provides feedback to individual students as they solve fractions problems individually. Three elementary schools participated in a randomized controlled experiment conducted in the 2007–2008 school year. Students in the TechPALS condition learned more than did the control group students, with effect sizes ranging from d = 0.14 to d = 0.44. Analysis of observational data confirmed that students in the TechPALS condition participated socially in questioning, explaining, and discussing disagreements, whereas students in the individual condition did not. We conclude that an integration of technology, cooperative activity designs and broader educational practices can lead to impact on students’ mathematics learning.