Muscle activation characteristics in cross-country skiers with a history of anterior compartment pain

A large proportion of elite cross-country skiers suffer from chronic anterior compartment syndrome (CACS). This study used surface electromyograms (EMGs) to investigate whether differences existed in the activation characteristics of the tibialis anterior muscle between elite cross-country skiers with a history of anterior compartment pain (symptomatic group) and a pain-free control group. Based on self-reported pain symptoms, twelve young, national-level cross-country ski athletes were assigned to a symptomatic group (N = 5), a control group (N = 4), or analyzed individually if their diagnosis was not certain (N = 3). During skating, EMGs were recorded on five lower leg muscles. The relative increase in EMG power per step when increasing the effort level of skating was larger in the symptomatic group than in the control group for tibialis anterior (143 ± 12% vs. 125 ± 23%; Cohen's d = 1.17), peroneus longus (123 ± 24% vs. 107 ± 6%; d = 0.91), and gastrocnemius lateralis (167 ± 51% vs. 117 ± 12%; d = 1.64). The symptomatic group showed more power in the lower frequency bands of the tibialis anterior's EMG spectra (p < 0.001), whereas no group differences were found in other muscles (all p>0.2). Within the step cycle, these differences appeared in the swing phase and in the gliding phase during single leg support. The observed differences in the EMG spectra may serve as an early identification of athletes who are at risk of developing CACS.     

Differential trust between parents and teachers of children from low-income and immigrant backgrounds

This study was designed to investigate the trust relationship between parents and teachers in first grade. Additional research questions were whether trust was related to ethnicity and reading performance. The five facets of trust; benevolence, reliability, competence, honesty and openness, were measured on a 4-point Likert scale. Reading performance was measured by the three-minute test. Parents were found to have more trust in the reliability, competence and honesty of teachers than teachers in parents. Native-Dutch and immigrant parents have the same trust level towards their children’s teacher. However, teachers reported lower trust levels on all five facets of trust for immigrant parents. Our findings indicated that ethnicity has no influence on parents trust in teachers, but ethnicity may explain teachers’ trust in parents. Some support was found for the assumption that teachers’ trust plays a role in reading performance. Children were found to have higher reading performance when teachers reported higher trust in the benevolence and openness of parents.