Different systems—Similar challenges? Factors impacting the motivation of German and U.S. teachers to become school leaders

In the United States and Germany, effective school leadership is pivotal to a school's success. Yet in each country, attracting and retaining qualified school leaders is a formidable challenge. This study compares the influence of possible motivators and inhibitors that impact teachers’ decisions to become principals in the two countries. Survey responses of 311 U.S. students in principal preparation programs in the United States and responses of 117 German students in similar programs in Germany indicate that many factors that motivate and inhibit U.S. and German teachers to become school leaders are similar. The results also reveal areas in which the U.S. and Germany may learn from each other regarding motivators and inhibitors to becoming school administrators.     

Energy system contribution to 1500- and 3000-metre track running

The aim of the present study was to quantify the contributions of the aerobic and anaerobic energy systems to 1500- and 3000-m track running events during all-out time-trials performed individually on a synthetic athletic track. Ten 3000-m (8 males, 2 females) and fourteen 1500-m (10 males, 4 females) trained track athletes volunteered to participate in the study. The athletes performed a graded exercise test in the laboratory and two time-trials over 1500 or 3000 m. The contributions of the energy systems were calculated by measures of race oxygen uptake, accumulated oxygen deficit (AOD), race blood lactate concentration, estimated phosphocreatine degradation and some individual muscle metabolite data. The relative aerobic energy system contribution (based on AOD measures) for the 3000 m was 86% (male) and 94% (female), while for the 1500 m it was 77% (male) and 86% (female). Estimates of anaerobic energy expenditure based on blood lactate concentrations, while not significantly different (P > 0.05), were generally lower compared with the AOD measures. In conclusion, the results of the present study conform with some recent laboratory-based measures of energy system contributions to these events.     

Concentric left ventricular morphology in aerobically trained kayak canoeists

The aim of the present study was to test the hypothesis that upper body aerobically trained athletes (kayak canoeists) would have greater left ventricular wall thickness, but similar left ventricular diastolic chamber dimensions, compared with recreationally active and sedentary men. Ultrasound echocardiography was used to determine cardiac structure and function in highly trained kayak canoeists (n = 10), moderately active (n = 10) and sedentary men (n = 10). The septal and posterior left ventricular walls were approximately 0.2 cm thicker in kayak canoeists (P < 0.05), and left ventricular mass was 51% and 32% greater (P < 0.05) in canoeists than in the sedentary and moderately trained participants, respectively. There were no differences in left ventricular chamber dimension, suggesting that the kayak canoeists had a concentric pattern of left ventricular adaptation to aerobic upper body training. Scaling the data to body composition indices had no effect on the outcome of the statistical analysis. There were no differences in resting Doppler left ventricular diastolic or systolic function among the groups. Ejection fraction was lower in the kayak canoeists, but the magnitude of the difference was within the normal variability for this measurement. Thus aerobically upper body trained athletes demonstrated a concentric pattern of cardiac enlargement, but resting left ventricle function was not different between athletes, moderately active and sedentary individuals.