@article{SalzwedelReibisHadzicetal.2019, author = {Salzwedel, Annett and Reibis, Rona Katharina and Hadzic, Miralem and Buhlert, Hermann and V{\"o}ller, Heinz}, title = {Patients' expectations of returning to work, co-morbid disorders and work capacity at discharge from cardiac rehabilitation}, series = {Vascular Health and Risk Management}, volume = {15}, journal = {Vascular Health and Risk Management}, publisher = {Dove Medical Press}, address = {Albany, Auckland}, issn = {1176-6344}, doi = {10.2147/VHRM.S216039}, pages = {301 -- 308}, year = {2019}, abstract = {Objective: We aimed to characterize patients after an acute cardiac event regarding their negative expectations around returning to work and the impact on work capacity upon discharge from cardiac rehabilitation (CR). Methods: We analyzed routine data of 884 patients (52±7 years, 76\% men) who attended 3 weeks of inpatient CR after an acute coronary syndrome (ACS) or cardiac surgery between October 2013 and March 2015. The primary outcome was their status determining their capacity to work (fit vs unfit) at discharge from CR. Further, sociodemographic data (eg, age, sex, and education level), diagnoses, functional data (eg, exercise stress test and 6-min walking test [6MWT]), the Hospital Anxiety and Depression Scale (HADS) and self-assessment of the occupational prognosis (negative expectations and/or unemployment, W{\"u}rzburger screening) at admission to CR were considered. Results: A negative occupational prognosis was detected in 384 patients (43\%). Out of these, 368 (96\%) expected not to return to work after CR and/or were unemployed before CR at 29\% (n=113). Affected patients showed a reduced exercise capacity (bicycle stress test: 100 W vs 118 W, P<0.01; 6MWT: 380 m vs 421 m, P<0.01) and were more likely to receive a depression diagnosis (12\% vs 3\%, P<0.01), as well as higher levels on the HADS. At discharge from CR, 21\% of this group (n=81) were fit for work (vs 35\% of patients with a normal occupational prognosis (n=175, P<0.01)). Sick leave before the cardiac event (OR 0.4, 95\% CI 0.2-0.6, P<0.01), negative occupational expectations (OR 0.4, 95\% CI 0.3-0.7, P<0.01) and depression (OR 0.3, 95\% CI 0.1-0.8, P=0.01) reduced the likelihood of achieving work capacity upon discharge. In contrast, higher exercise capacity was positively associated. Conclusion: Patients with a negative occupational prognosis often revealed a reduced physical performance and suffered from a high psychosocial burden. In addition, patients' occupational expectations were a predictor of work capacity at discharge from CR. Affected patients should be identified at admission to allow for targeted psychosocial care.}, language = {en} } @article{StrotsevaFeinschmidtSchipkeGunteretal.2019, author = {Strotseva-Feinschmidt, Anna and Schipke, Christine S. and Gunter, Thomas C. and Brauer, Jens and Friederici, Angela D.}, title = {Young children's sentence comprehension}, series = {Brain and cognition : a journal of experimental and clinical research}, volume = {134}, journal = {Brain and cognition : a journal of experimental and clinical research}, publisher = {Elsevier}, address = {San Diego}, issn = {0278-2626}, doi = {10.1016/j.bandc.2018.09.003}, pages = {110 -- 121}, year = {2019}, abstract = {Sentence comprehension requires the assignment of thematic relations between the verb and its noun arguments in order to determine who is doing what to whom. In some languages, such as English, word order is the primary syntactic cue. In other languages, such as German, case-marking is additionally used to assign thematic roles. During development children have to acquire the thematic relevance of these syntactic cues and weigh them against semantic cues. Here we investigated the processing of syntactic cues and semantic cues in 2- and 3-year-old children by analyzing their behavioral and neurophysiological responses. Case-marked subject-first and object-first sentences (syntactic cue) including animate and inanimate nouns (semantic cue) were presented auditorily. The semantic animacy cue either conflicted with or supported the thematic roles assigned by syntactic case-marking. In contrast to adults, for whom semantics did not interfere with case-marking, children attended to both syntactic and to semantic cues with a stronger reliance on semantic cues in early development. Children's event-related brain potentials indicated sensitivity to syntactic information but increased processing costs when case-marking and animacy assigned conflicting thematic roles. These results demonstrate an early developmental sensitivity and ongoing shift towards the use of syntactic cues during sentence comprehension.}, language = {en} } @article{GarciaRoeserHoehle2019, author = {Garc{\´i}a, Rowena and Roeser, Jens and H{\"o}hle, Barbara}, title = {Thematic role assignment in the L1 acquisition of Tagalog}, series = {Language acquisition : a journal of developmental linguistics}, volume = {26}, journal = {Language acquisition : a journal of developmental linguistics}, number = {3}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {1048-9223}, doi = {10.1080/10489223.2018.1525613}, pages = {235 -- 261}, year = {2019}, abstract = {It is a common finding across languages that young children have problems in understanding patient-initial sentences. We used Tagalog, a verb-initial language with a reliable voice-marking system and highly frequent patient voice constructions, to test the predictions of several accounts that have been proposed to explain this difficulty: the frequency account, the Competition Model, and the incremental processing account. Study 1 presents an analysis of Tagalog child-directed speech, which showed that the dominant argument order is agent-before-patient and that morphosyntactic markers are highly valid cues to thematic role assignment. In Study 2, we used a combined self-paced listening and picture verification task to test how Tagalog-speaking adults and 5- and 7-year-old children process reversible transitive sentences. Results showed that adults performed well in all conditions, while children's accuracy and listening times for the first noun phrase indicated more difficulty in interpreting patient-initial sentences in the agent voice compared to the patient voice. The patient voice advantage is partly explained by both the frequency account and incremental processing account.}, language = {en} } @article{WeymarVenturaBortWendtetal.2019, author = {Weymar, Mathias and Ventura-Bort, Carlos and Wendt, Julia and Lischke, Alexander}, title = {Behavioral and neural evidence of enhanced long-term memory for untrustworthy faces}, series = {Scientific Reports}, volume = {9}, journal = {Scientific Reports}, publisher = {Macmillan Publishers Limited}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-019-55705-7}, pages = {8}, year = {2019}, abstract = {In daily life, we automatically form impressions of other individuals on basis of subtle facial features that convey trustworthiness. Because these face-based judgements influence current and future social interactions, we investigated how perceived trustworthiness of faces affects long-term memory using event-related potentials (ERPs). In the current study, participants incidentally viewed 60 neutral faces differing in trustworthiness, and one week later, performed a surprise recognition memory task, in which the same old faces were presented intermixed with novel ones. We found that after one week untrustworthy faces were better recognized than trustworthy faces and that untrustworthy faces prompted early (350-550 ms) enhanced frontal ERP old/new differences (larger positivity for correctly remembered old faces, compared to novel ones) during recognition. Our findings point toward an enhanced long-lasting, likely familiarity-based, memory for untrustworthy faces. Even when trust judgments about a person do not necessarily need to be accurate, a fast access to memories predicting potential harm may be important to guide social behaviour in daily life.}, language = {en} } @article{CzapkaKlassertFestman2019, author = {Czapka, Sophia and Klassert, Annegret and Festman, Julia}, title = {Executive Functions and Language}, series = {Frontiers in Psychology}, volume = {10}, journal = {Frontiers in Psychology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2019.00097}, pages = {18}, year = {2019}, abstract = {We aimed at unveiling the role of executive functions (EFs) and language-related skills in spelling for mono- versus multilingual primary school children. We focused on EF and language-related skills, in particular lexicon size and phonological awareness (PA), because these factors were found to predict spelling in studies predominantly conducted with monolinguals, and because multilingualism can modulate these factors. There is evidence for (a) a bilingual advantage in EF due to constant high cognitive demands through language control, (b) a smaller mental lexicon in German and (c) possibly better PA. Multilinguals in Germany show on average poorer German language proficiency, what can influence performance on language-based tasks negatively. Thus, we included two spelling tasks to tease apart spelling based on lexical knowledge (i.e., word spelling) from spelling based on non-lexical strategies (i.e., non-word spelling). Our sample consisted of heterogeneous third graders from Germany: 69 monolinguals (age: M = 108 months) and 57 multilinguals (age: M = 111 months). On less language-dependent tasks (e.g., non-word spelling, PA, intelligence, short-term memory (STM) and three EF tasks testing switching, inhibition, and working memory) performance of both groups did not differ significantly. However, multilinguals performed significantly more poorly on tasks measuring German lexicon size and word spelling than monolinguals. Regression analyses revealed that for multilinguals, inhibition was related to spelling, whereas switching was the only EF component to influence word spelling in monolinguals and non-word spelling performance in both groups. By adding lexicon size and other language-related factors to the regression models, the influence of switching was reduced to insignificant effects, but inhibition remained significant for multilinguals. Language-related skills best predicted spelling and both language groups shared those variables: PA for word spelling, and STM for non-word spelling. Additionally, multilinguals' word spelling performance was also predicted by their German lexicon size, and non-word spelling performance by PA. This study offers an in-depth look at spelling acquisition at a certain point of literacy development. Mono- and multilinguals have the predominant factors for spelling in common, but probably due to superior language knowledge, monolinguals were already able to make use of EF during spelling. For multilinguals, German lexicon size was more important for spelling than EF. For multilinguals' spelling these functions might come into play only at a later stage.}, language = {en} } @article{WarschburgerZitzmann2019, author = {Warschburger, Petra and Zitzmann, Jana}, title = {Does an Age-Specific Treatment Program Augment the Efficacy of a Cognitive-Behavioral Weight Loss Program in Adolescence and Young Adulthood?}, series = {Nutrients}, volume = {2019}, journal = {Nutrients}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {2072-6643}, doi = {10.3390/nu11092053}, pages = {18}, year = {2019}, abstract = {Research on weight-loss interventions in emerging adulthood is warranted. Therefore, a cognitive-behavioral group treatment (CBT), including development-specific topics for adolescents and young adults with obesity (YOUTH), was developed. In a controlled study, we compared the efficacy of this age-specific CBT group intervention to an age-unspecific CBT group delivered across ages in an inpatient setting. The primary outcome was body mass index standard deviation score (BMI-SDS) over the course of one year; secondary outcomes were health-related and disease-specific quality of life (QoL). 266 participants aged 16 to 21 years (65\% females) were randomized. Intention-to-treat (ITT) and per-protocol analyses (PPA) were performed. For both group interventions, we observed significant and clinically relevant improvements in BMI-SDS and QoL over the course of time with small to large effect sizes. Contrary to our hypothesis, the age-specific intervention was not superior to the age-unspecific CBT-approach.}, language = {en} } @phdthesis{Scheithauer2019, author = {Scheithauer, Linda}, title = {What have you been doing besides studying? Evaluators' competence attributions on extracurricular activities in application documents}, pages = {213}, year = {2019}, language = {en} } @article{FayUrbachScheithauer2019, author = {Fay, Doris and Urbach, Tina and Scheithauer, Linda}, title = {What motivates you right now?}, series = {Measurement Instruments for the Social Sciences}, volume = {2}, journal = {Measurement Instruments for the Social Sciences}, number = {5}, publisher = {BioMed Central}, address = {London}, issn = {2523-8930}, doi = {10.1186/s42409-019-0007-7}, pages = {17}, year = {2019}, abstract = {Regulatory focus is a motivational construct that describes humans' motivational orientation during goal pursuit. It is conceptualized as a chronic, trait-like, as well as a momentary, state-like orientation. Whereas there is a large number of measures to capture chronic regulatory focus, measures for its momentary assessment are only just emerging. This paper presents the development and validation of a measure of Momentary-Chronic Regulatory Focus. Our development incorporates the distinction between self-guide and reference-point definitions of regulatory focus. Ideals and ought striving are the promotion and prevention dimension in the self-guide system; gain and non-loss regulatory focus are the respective dimensions within the reference-point system. Three-survey-based studies test the structure, psychometric properties, and validity of the measure in its version to assess chronic regulatory focus (two samples of working participants, N = 389, N = 672; one student sample [time 1, N = 105; time 2, n = 91]). In two further studies, an experience sampling study with students (N = 84, k = 1649) and a daily-diary study with working individuals (N = 129, k = 1766), the measure was applied to assess momentary regulatory focus. Multilevel analyses test the momentary measure's factorial structure, provide support for its sensitivity to capture within-person fluctuations, and provide evidence for concurrent construct validity.}, language = {en} } @article{GrubicWierzba2019, author = {Grubic, Mira and Wierzba, Marta}, title = {Presupposition Accommodation of the German Additive Particle auch (= "too")}, series = {Frontiers in Communication}, volume = {4}, journal = {Frontiers in Communication}, publisher = {Frontiers Media}, address = {Lausanne}, issn = {2297-900X}, doi = {10.3389/fcomm.2019.00015}, pages = {18}, year = {2019}, abstract = {Presupposition triggers differ with respect to whether their presupposition is easily accommodatable. The presupposition of focus-sensitive additive particles like also or too is often classified as hard to accommodate, i.e., these triggers are infelicitous if their presupposition is not entailed by the immediate linguistic or non-linguistic context. We tested two competing accounts for the German additive particle auch concerning this requirement: First, that it requires a focus alternative to the whole proposition to be salient, and second, that it merely requires an alternative to the focused constituent (e.g., an individual) to be salient. We conducted two experiments involving felicity judgments as well as questions asking for the truth of the presupposition to be accommodated. Our results suggest that the latter account is too weak: mere previous mention of a potential alternative to the focused constituent is not enough to license the use of auch. However, our results also suggest that the former account is too strong: when an alternative of the focused constituent is prementioned and certain other accommodation-enhancing factors are present, the context does not have to entail the presupposed proposition. We tested the following two potentially accommodation-enhancing factors: First, whether the discourse can be construed to be from the perspective of the individual that the presupposition is about, and second, whether the presupposition is needed to establish coherence between the host sentence of the additive particle and the preceding context. The factor coherence was found to play a significant role. Our results thus corroborate the results of other researchers showing that discourse participants go to great lengths in order to identify a potential presupposition to accommodate, and we contribute to these results by showing that coherence is one of the factors that enhance accommodation.}, language = {en} } @article{KulkovaFischer2019, author = {Kulkova, Elena S. and Fischer, Martin H.}, title = {Idioms in the World}, series = {Frontiers in Psychology}, volume = {10}, journal = {Frontiers in Psychology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2019.01155}, pages = {4}, year = {2019}, language = {en} } @article{KuehneMaasWiesenthaletal.2019, author = {K{\"u}hne, Franziska and Maas, Jana and Wiesenthal, Sophia and Weck, Florian}, title = {Empirical research in clinical supervision}, series = {BMC Psychology}, volume = {7}, journal = {BMC Psychology}, publisher = {BioMed Central}, address = {London}, issn = {2050-7283}, doi = {10.1186/s40359-019-0327-7}, pages = {11}, year = {2019}, abstract = {Background: Although clinical supervision is considered to be a major component of the development and maintenance of psychotherapeutic competencies, and despite an increase in supervision research, the empirical evidence on the topic remains sparse. Methods: Because most previous reviews lack methodological rigor, we aimed to review the status and quality of the empirical literature on clinical supervision, and to provide suggestions for future research. MEDLINE, PsycInfo and the Web of Science Core Collection were searched and the review was conducted according to current guidelines. From the review results, we derived suggestions for future research on clinical supervision. Results: The systematic literature search identified 19 publications from 15 empirical studies. Taking into account the review results, the following suggestions for further research emerged: Supervision research would benefit from proper descriptions of how studies are conducted according to current guidelines, more methodologically rigorous empirical studies, the investigation of active supervision interventions, from taking diverse outcome domains into account, and from investigating supervision from a meta-theoretical perspective. Conclusions: In all, the systematic review supported the notion that supervision research often lags behind psychotherapy research in general. Still, the results offer detailed starting points for further supervision research.}, language = {en} } @article{BrandUlrich2019, author = {Brand, Ralf and Ulrich, Lukas}, title = {I Can See It in Your Face.}, series = {Frontiers in Psychology}, volume = {10}, journal = {Frontiers in Psychology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2019.02901}, pages = {11}, year = {2019}, abstract = {The purpose of this study was to illustrate that people's affective valuation of exercise can be identified in their faces. The study was conducted with a software for automatic facial expression analysis and it involved testing the hypothesis that positive or negative affective valuation occurs spontaneously when people are reminded of exercise. We created a task similar to an emotional Stroop task, in which participants responded to exercise-related and control stimuli with a positive or negative facial expression (smile or frown) depending on whether the photo was presented upright or tilted. We further asked participants how much time they would normally spend for physical exercise, because we assumed that the affective valuation of those who exercise more would be more positive. Based on the data of 86 participants, regression analysis revealed that those who reported less exercise and a more negative reflective evaluation of exercise initiated negative facial expressions on exercise-related stimuli significantly faster than those who reported exercising more often. No significant effect was observed for smile responses. We suspect that responding with a smile to exercise-related stimuli was the congruent response for the majority of our participants, so that for them no Stroop interference occurred in the exercise-related condition. This study suggests that immediate negative affective reactions to exercise-related stimuli result from a postconscious automatic process and can be detected in the study participants' faces. It furthermore illustrates how methodological paradigms from social-cognition research (here: the emotional Stroop paradigm) can be adapted to collect and analyze biometric data for the investigation of exercisers' and non-exercisers' automatic valuations of exercise.}, language = {en} } @article{JeglinskiMende2019, author = {Jeglinski-Mende, Melinda A.}, title = {Alcohol in the Aging Brain}, series = {Frontiers in Neuroscience}, volume = {13}, journal = {Frontiers in Neuroscience}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1662-453X}, doi = {10.3389/fnins.2019.00713}, pages = {7}, year = {2019}, abstract = {As our society grows older new challenges for medicine and healthcare emerge. Agerelated changes of the body have been observed in essential body functions, particularly in the loco-motor system, in the cardiovascular system and in cognitive functions concerning both brain plasticity and changes in behavior. Nutrition and lifestyle, such as nicotine intake and chronic alcohol consumption, also contribute to biological changes in the brain. This review addresses the effect of alcohol consumption on cognitive decline, changes in brain plasticity in the aging brain and on cardiovascular health in aging. Thus, studies on the interplay of chronic alcohol intake and either cognitive decline or cognitive preservation are outlined. Because of the inconsistency in the literature of whether alcohol consumption preserves cognitive functions in the aging brain or whether it accelerates cognitive decline, it is crucial to consider individual contributing factors such as culture, health and lifestyle in future studies.}, language = {en} } @misc{SchusterKrahe2019, author = {Schuster, Isabell and Krahe, Barbara}, title = {Prevalence of Sexual Aggression Victimization and Perpetration in Chile}, series = {Trauma violence \& abuse}, volume = {20}, journal = {Trauma violence \& abuse}, number = {2}, publisher = {Sage Publ.}, address = {Thousand Oaks}, issn = {1524-8380}, doi = {10.1177/1524838017697307}, pages = {229 -- 244}, year = {2019}, abstract = {Sexual aggression is a major public health issue worldwide, but most knowledge is derived from studies conducted in North America and Western Europe. Little research has been conducted on the prevalence of sexual aggression in developing countries, including Chile. This article presents the first systematic review of the evidence on the prevalence of sexual aggression victimization and perpetration among women and men in Chile. Furthermore, it reports differences in prevalence rates in relation to victim and perpetrator characteristics and victim-perpetrator relationships. A total of N = 28 studies were identified by a three-stage literature search, including the screening of academic databases, publications of Chilean institutions, and reference lists. A great heterogeneity was found for prevalence rates of sexual victimization, ranging between 1.0\% and 51.9\% for women and 0.4\% and 48.0\% for men. Only four studies provided perpetration rates, which varied between 0.8\% and 26.8\% for men and 0.0\% and 16.5\% for women. No consistent evidence emerged for differences in victimization rates in relation to victims' gender, age, and education. Perpetrators were more likely to be persons known to the victim. Conceptual and methodological differences between the studies are discussed as reasons for the great variability in prevalence rates, and recommendations are provided for a more harmonized and gender-inclusive approach for future research on sexual aggression in Chile.}, language = {en} } @article{HiltonRaelingWartenburgeretal.2019, author = {Hilton, Matt and R{\"a}ling, Romy and Wartenburger, Isabell and Elsner, Birgit}, title = {Parallels in Processing Boundary Cues in Speech and Action}, series = {Frontiers in Psychology}, volume = {10}, journal = {Frontiers in Psychology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2019.01566}, pages = {12}, year = {2019}, abstract = {Speech and action sequences are continuous streams of information that can be segmented into sub-units. In both domains, this segmentation can be facilitated by perceptual cues contained within the information stream. In speech, prosodic cues (e.g., a pause, pre-boundary lengthening, and pitch rise) mark boundaries between words and phrases, while boundaries between actions of an action sequence can be marked by kinematic cues (e.g., a pause, pre-boundary deceleration). The processing of prosodic boundary cues evokes an Event-related Potentials (ERP) component known as the Closure Positive Shift (CPS), and it is possible that the CPS reflects domaingeneral cognitive processes involved in segmentation, given that the CPS is also evoked by boundaries between subunits of non-speech auditory stimuli. This study further probed the domain-generality of the CPS and its underlying processes by investigating electrophysiological correlates of the processing of boundary cues in sequences of spoken verbs (auditory stimuli; Experiment 1; N = 23 adults) and actions (visual stimuli; Experiment 2; N = 23 adults). The EEG data from both experiments revealed a CPS-like broadly distributed positivity during the 250 ms prior to the onset of the post-boundary word or action, indicating similar electrophysiological correlates of boundary processing across domains, suggesting that the cognitive processes underlying speech and action segmentation might also be shared.}, language = {en} } @article{SchwarzenthalJuangSchachneretal.2019, author = {Schwarzenthal, Miriam and Juang, Linda P. and Schachner, Maja Katharina and van de Vijver, Fons J. R.}, title = {A multimodal measure of cultural intelligence for adolescents growing up in culturally diverse societies}, series = {International Journal of Intercultural Relations}, volume = {72}, journal = {International Journal of Intercultural Relations}, publisher = {Elsevier}, address = {Oxford}, issn = {0147-1767}, doi = {10.1016/j.ijintrel.2019.07.007}, pages = {109 -- 121}, year = {2019}, abstract = {Adolescents growing up in culturally diverse societies need to develop intercultural competence. To better understand how to develop intercultural competence we need measures specifically relating to the everyday intercultural experiences of adolescents. However, few measures of intercultural competence are available for this target group. Based on the cultural intelligence (CQ) model (Earley \& Ang, 2003), we developed a measure that combines a self-report questionnaire and situational judgment tests (SJTs). The latter comprise a brief description of intercultural situations, followed by questions asking the adolescents to interpret and provide a reaction to the situations. The reliability, factor structure, measurement equivalence, and validity of the new measure was tested in two samples of adolescents in culturally diverse regions in North Rhine-Westphalia (N = 631, 48\% female, M-a(ge) = 13.69 years, SDage = 1.83) and Berlin (N = 1,335, 48\% female, M-age = 14.69 years, SDage, = 0.74) in Germany. The self-report CQ scale showed good reliability and a four-dimensional factor structure with a higher-order CQ factor. The responses to the SJTs were coded based on a coding manual and the ratings loaded onto one factor. The measurement models showed metric to scalar measurement equivalence across immigrant background, gender, and grade. The CQ factor and the SJT factor were positively correlated with each other, as well as with related constructs such as openness, perspective-taking, and diversity beliefs. We conclude that the new measure offers a reliable and valid method to assess the intercultural competence of adolescents growing up in culturally diverse societies.}, language = {en} } @article{GebelLuederGranacher2019, author = {Gebel, Arnd and L{\"u}der, Benjamin and Granacher, Urs}, title = {Effects of Increasing Balance Task Difficulty on Postural Sway and Muscle Activity in Healthy Adolescents}, series = {Frontiers in Physiology}, volume = {10}, journal = {Frontiers in Physiology}, number = {9}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2019.01135}, pages = {13}, year = {2019}, abstract = {Evidence-based prescriptions for balance training in youth have recently been established. However, there is currently no standardized means available to assess and quantify balance task difficulty (BTD). Therefore, the objectives of this study were to examine the effects of graded BTD on postural sway, lower limb muscle activity and coactivation in adolescents. Thirteen healthy high-school students aged 16 to 17 volunteered to participate in this cross-sectional study. Testing involved participants to stand on a commercially available balance board with an adjustable pivot that allowed six levels of increasing task difficulty. Postural sway [i.e., total center of pressure (CoP) displacements] and lower limb muscle activity were recorded simultaneously during each trial. Surface electromyography (EMG) was applied in muscles encompassing the ankle (m. tibialis anterior, medial gastrocnemius, peroneus longus) and knee joint (m. vastus medialis, biceps femoris). The coactivation index (CAI) was calculated for ankle and thigh muscles. Repeated measures analyses of variance revealed a significant main effect of BTD with increasing task difficulty for postural sway (p < 0.001; d = 6.36), muscle activity (p < 0.001; 2.19 < d < 4.88), and CAI (p < 0.001; 1.32 < d < 1.41). Multiple regression analyses showed that m. tibialis anterior activity best explained overall CoP displacements with 32.5\% explained variance (p < 0.001). The observed increases in postural sway, lower limb muscle activity, and coactivation indicate increasing postural demands while standing on the balance board. Thus, the examined board can be implemented in balance training to progressively increase BTD in healthy adolescents.}, language = {en} } @article{ChaabeneBehmNegraetal.2019, author = {Chaabene, Helmi and Behm, David George and Negra, Yassine and Granacher, Urs}, title = {Acute Effects of Static Stretching on Muscle Strength and Power}, series = {Frontiers in Physiology}, volume = {10}, journal = {Frontiers in Physiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2019.01468}, pages = {8}, year = {2019}, abstract = {The effects of static stretching (StS) on subsequent strength and power activities has been one of the most debated topics in sport science literature over the past decades. The aim of this review is (1) to summarize previous and current findings on the acute effects of StS on muscle strength and power performances; (2) to update readers' knowledge related to previous caveats; and (3) to discuss the underlying physiological mechanisms of short-duration StS when performed as single-mode treatment or when integrated into a full warm-up routine. Over the last two decades, StS has been considered harmful to subsequent strength and power performances. Accordingly, it has been recommended not to apply StS before strength- and power-related activities. More recent evidence suggests that when performed as a single-mode treatment or when integrated within a full warm-up routine including aerobic activity, dynamic-stretching, and sport-specific activities, short-duration StS (≤60 s per muscle group) trivially impairs subsequent strength and power activities (∆1-2\%). Yet, longer StS durations (>60 s per muscle group) appear to induce substantial and practically relevant declines in strength and power performances (∆4.0-7.5\%). Moreover, recent evidence suggests that when included in a full warm-up routine, short-duration StS may even contribute to lower the risk of sustaining musculotendinous injuries especially with high-intensity activities (e.g., sprint running and change of direction speed). It seems that during short-duration StS, neuromuscular activation and musculotendinous stiffness appear not to be affected compared with long-duration StS. Among other factors, this could be due to an elevated muscle temperature induced by a dynamic warm-up program. More specifically, elevated muscle temperature leads to increased muscle fiber conduction-velocity and improved binding of contractile proteins (actin, myosin). Therefore, our previous understanding of harmful StS effects on subsequent strength and power activities has to be updated. In fact, short-duration StS should be included as an important warm-up component before the uptake of recreational sports activities due to its potential positive effect on flexibility and musculotendinous injury prevention. However, in high-performance athletes, short-duration StS has to be applied with caution due to its negligible but still prevalent negative effects on subsequent strength and power performances, which could have an impact on performance during competition.}, language = {en} } @article{JafarnezhadgeroFatollahiAmirzadehetal.2019, author = {Jafarnezhadgero, Amir Ali and Fatollahi, Amir and Amirzadeh, Nasrin and Siahkouhian, Marefat and Granacher, Urs}, title = {Ground Reaction Forces and Muscle Activity While Walking on Sand versus Stable Ground in Individuals with Pronated Feet Compared with Healthy Controls}, series = {PloS ONe}, volume = {9}, journal = {PloS ONe}, number = {14}, publisher = {PloS ONe}, address = {San Francisco, California}, issn = {1932-6203}, doi = {10.1371/journal.pone.0223219}, pages = {15}, year = {2019}, abstract = {Background Sand is an easy-to-access, cost-free resource that can be used to treat pronated feet (PF). Therefore, the aims of this study were to contrast the effects of walking on stable ground versus walking on sand on ground reaction forces (GRFs) and electromyographic (EMG) activity of selected lower limb muscles in PF individuals compared with healthy controls. Methods Twenty-nine controls aged 22.2±2.5 years and 30 PF individuals aged 22.2±1.9 years were enrolled in this study. Participants walked at preferred speed and in randomized order over level ground and sand. A force plate was included in the walkway to collect GRFs. Muscle activities were recorded using EMG system. Results No statistically significant between-group differences were found in preferred walking speed when walking on stable ground (PF: 1.33±0.12 m/s; controls: 1.35±0.14 m/s; p = 0.575; d = 0.15) and sand (PF: 1.19±0.11 m/s; controls: 1.23±0.18 m/s; p = 0.416; d = 0.27). Irrespective of the group, walking on sand (1.21±0.15 m/s) resulted in significantly lower gait speed compared with stable ground walking (1.34±0.13 m/s) (p<0.001; d = 0.93). Significant main effects of "surface" were found for peak posterior GRFs at heel contact, time to peak for peak lateral GRFs at heel contact, and peak anterior GRFs during push-off (p<0.044; d = 0.27-0.94). Pair-wise comparisons revealed significantly smaller peak posterior GRFs at heel contact (p = 0.005; d = 1.17), smaller peak anterior GRFs during push-off (p = 0.001; d = 1.14), and time to peak for peak lateral GRFs (p = 0.044; d = 0.28) when walking on sand. No significant main effects of "group" were observed for peak GRFs and their time to peak (p>0.05; d = 0.06-1.60). We could not find any significant group by surface interactions for peak GRFs and their time to peak. Significant main effects of "surface" were detected for anterior-posterior impulse and peak positive free moment amplitude (p<0.048; d = 0.54-0.71). Pair-wise comparisons revealed a significantly larger peak positive free moment amplitude (p = 0.010; d = 0.71) and a lower anterior-posterior impulse (p = 0.048; d = 0.38) when walking on sand. We observed significant main effects of "group" for the variable loading rate (p<0.030; d = 0.59). Pair-wise comparisons revealed significantly lower loading rates in PF compared with controls (p = 0.030; d = 0.61). Significant group by surface interactions were observed for the parameter peak positive free moment amplitude (p<0.030; d = 0.59). PF individuals exhibited a significantly lower peak positive free moment amplitude (p = 0.030, d = 0.41) when walking on sand. With regards to EMG, no significant main effects of "surface", main effects of "group", and group by surface interactions were observed for the recorded muscles during the loading and push-off phases (p>0.05; d = 0.00-0.53). Conclusions The observed lower velocities during walking on sand compared with stable ground were accompanied by lower peak positive free moments during the push-off phase and loading rates during the loading phase. Our findings of similar lower limb muscle activities during walking on sand compared with stable ground in PF together with lower free moment amplitudes, vertical loading rates, and lower walking velocities on sand may indicate more relative muscle activity on sand compared with stable ground. This needs to be verified in future studies.}, language = {en} } @article{ElAshkerChaabenePrieskeetal.2019, author = {El-Ashker, Said and Chaabene, Helmi and Prieske, Olaf and Abdelkafy, Ashraf and Ahmed, Mohamed A. and Muaidi, Qassim I. and Granacher, Urs}, title = {Effects of Neuromuscular Fatigue on Eccentric Strength and Electromechanical Delay of the Knee Flexors}, series = {Frontiers in Physiology}, volume = {10}, journal = {Frontiers in Physiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2019.00782}, pages = {9}, year = {2019}, abstract = {Purpose: To examine the effects of fatiguing isometric contractions on maximal eccentric strength and electromechanical delay (EMD) of the knee flexors in healthy young adults of different training status. Methods: Seventy-five male participants (27.7 ± 5.0 years) were enrolled in this study and allocated to three experimental groups according to their training status: athletes (ATH, n = 25), physically active adults (ACT, n = 25), and sedentary participants (SED, n = 25). The fatigue protocol comprised intermittent isometric knee flexions (6-s contraction, 4-s rest) at 60\% of the maximum voluntary contraction until failure. Pre- and post-fatigue, maximal eccentric knee flexor strength and EMDs of the biceps femoris, semimembranosus, and semitendinosus muscles were assessed during maximal eccentric knee flexor actions at 60, 180, and 300°/s angular velocity. An analysis of covariance was computed with baseline (unfatigued) data included as a covariate. Results: Significant and large-sized main effects of group (p ≤ 0.017, 0.87 ≤ d ≤ 3.69) and/or angular velocity (p < 0.001, d = 1.81) were observed. Post hoc tests indicated that regardless of angular velocity, maximal eccentric knee flexor strength was lower and EMD was longer in SED compared with ATH and ACT (p ≤ 0.025, 0.76 ≤ d ≤ 1.82) and in ACT compared with ATH (p = ≤0.025, 0.76 ≤ d ≤ 1.82). Additionally, EMD at post-test was significantly longer at 300°/s compared with 60 and 180°/s (p < 0.001, 2.95 ≤ d ≤ 4.64) and at 180°/s compared with 60°/s (p < 0.001, d = 2.56), irrespective of training status. Conclusion: The main outcomes revealed significantly higher maximal eccentric strength and shorter eccentric EMDs of knee flexors in individuals with higher training status (i.e., athletes) following fatiguing exercises. Therefore, higher training status is associated with better neuromuscular functioning (i.e., strength, EMD) of the hamstring muscles in fatigued condition. Future longitudinal studies are needed to substantiate the clinical relevance of these findings.}, language = {en} }