Modifying the System for Observing Fitness Instruction Time to Measure Teacher Practices Related to Physical Activity Promotion: SOFIT+

The System for Observing Fitness Instruction Time (SOFIT) is commonly used to measure variables related to physical activity during physical education (PE). However, SOFIT does not yield detailed information about teacher practices related to children’s moderate-to-vigorous physical activity (MVPA). This study describes the modification of SOFIT (referred to as SOFIT+) to measure teacher practices related to students’ MVPA during PE lessons. Teacher practices that (a) promote and (b) limit children’s MVPA were identified and operationally defined via a literature review and Delphi Method. Reliability and validity data for SOFIT+ were obtained from 20 video recorded elementary PE lessons. Validity of teacher behaviors included in SOFIT+ was established using students’ accelerometer-derived MVPA. Twenty-seven teacher practices were identified. Inter-rater agreement ranged from 75.8% to 99.1% across 724 reliability scans. Six and seven practices were independently related to girls’ and boys’ MVPA, respectively. For example, during elimination activities, boys and girls were less likely to engage in MVPA. Boys were up to 1.51 times more likely to engage in MVPA while girls were up to 2.86 times more likely to engage in MVPA when a greater number of teacher practices were observed concurrently. Findings provide preliminary reliability and validity for SOFIT+, an instrument to comprehensively measure teacher practices related to children’s MVPA during PE.     

Scoring Neutral or Unsure on an Identity Development Instrument for Higher Education

The use of neutral or unsure on an instrument designed to measure identity development in college students was explored. The nominal response model from item response theory was used to evaluate whether neutral or unsure was used more frequently by those at low or middle levels of development; the results depended on the subscale and sometimes on the item within the subscale. Scoring based on the nominal response model allows for this category to be treated differently for different items.     

Effect of a novel pedal design on maximal power output and mechanical efficiency in well-trained cyclists

In this study, we evaluated the effects of a novel pedal design, characterized by a downward and forward shift of the cleat fixing platform relative to the pedal axle, on maximal power output and mechanical efficiency in 22 well-trained cyclists. Maximal power output was measured during a series of short (5-s) intermittent sprints on an isokinetic cycle ergometer at cadences from 40 to 120 rev min(-1). Mechanical efficiency was evaluated during a submaximal incremental exercise test on a bicycle ergometer using continuous VO(2) and VCO(2) measurement. Similar tests with conventional pedals and the novel pedals, which were mounted on the individual racing bike of the participant, were randomized. Maximal power was greater with novel pedals than with conventional pedals (between 6.0%, s(x) = 1.5 at 40 rev min(-1) and 1.8%, s(x) = 0.7 at 120 rev min(-1); P = 0.01). Torque production between crank angles of 60 degrees and 150 degrees was higher with novel pedals than with conventional pedals (P = 0.004). The novel pedal design did not affect whole-body VO(2) or VCO(2). Mechanical efficiency was greater with novel pedals than with conventional pedals (27.2%, s(x) = 0.9 and 25.1%, s(x) = 0.9% respectively; P = 0.047; effect size = 0.9). In conclusion, the novel pedals can increase maximal power output and mechanical efficiency in well-trained cyclists.     

Physical fitness and academic achievement in third- and fifth-grade students

The relationship between physical fitness and academic achievement has received much attention owing to the increasing prevalence of children who are overweight and unfit, as well as the inescapable pressure on schools to produce students who meet academic standards. This study examined 259 public school students in third and fifth grades and found that field tests of physical fitness were positively related to academic achievement. Specifically, aerobic capacity was positively associated with achievement, whereas BMI was inversely related. Associations were demonstrated in total academic achievement, mathematics achievement, and reading achievement, thus suggesting that aspects of physical fitness may be globally related to academic performance in preadolescents. The findings are discussed with regards to maximizing school performance and the implications for educational policies.     

Knowledge exchange in clusters: The contingent role of regional inventive concentration

Geographic clusters confer advantages to collocated firms, in particular access to local know-how. This article argues that the access to local know-how is contingent on the extent to which inventive activity is concentrated in the cluster. We draw on sociological theories of generalized exchange to argue that contrasting logics of exchange emerge in geographic clusters that have opposing effects on the extent to which firms benefit from collaborating with local organizations and source local knowledge. A longitudinal data set of 1903 firms engaged in nanotechnology research is used to examine the relationship between firm co-authorships on scientific articles with firms and public research organizations (PROs) and firm inventive performance. Results indicate that when cluster-level firm inventive concentration is high, collaborations with local firms are associated with lower inventive performance. We also find that firms source less local knowledge for their own inventions when firm inventive concentration is high. In contrast, concentrated inventive activity among PROs increases the positive relationship between collaborations with local PROs and firm inventive performance. Results also show firms source more knowledge from local PROs when local PRO inventive concentration is high. The findings suggest that inventive concentration both helps and hinders spill-over of cutting-edge knowledge.