Open Access

Stretching is primarily used to improve flexibility, decrease stiffness of the muscle- tendon unit or reduce risk of injury. However, previous animal studies from 1970 to 1990 showed significant hypertrophy effects in skeletal muscle in response to chronic stretching intervention with stretching durations of 30 minutes to 24 hours per day. However, no study in humans was performed using comparatively long stretching durations of more than 30 minutes per day with a daily frequency. The present cumulative dissertation includes six studies aiming to investigate the effects of long-lasting static stretching training on maximum strength capacity, hypertrophy and flexibility in the skeletal muscle. Before starting own experimental studies, a meta-analysis of available animal research was conducted to analyze the potential of long-lasting stretching interventions on muscle mass and maximum strength. To induce long-lasting stretching on the plantar flexors and to improve standardization of the stretch training by quantifying the angle in the ankle joint while stretching, a calf muscle stretching orthosis was developed. In the following experimental studies, the orthosis was used to induce daily long- lasting static stretching stimuli with different stretching durations and intensities in the plantar flexors to assess different morphological and functional parameters. For this, a total of 311 participants were included in the studies and, dependent on the investigation, the effects of daily stretching for 10-120 minutes for six weeks were analyzed. Therefore, effects on maximal isometric and dynamic strength as well as flexibility of the plantar flexors were investigated with extended and flexed knee joint. The investigation of morphological parameters of the calf muscle was performed by determining the muscle thickness and the pennation angle by using sonographic imaging and the muscle cross-sectional area by using a 3 Tesla magnetic resonance imaging measurement. In animals, the included systematic review with meta-analysis revealed increases in muscle mass with large effect size (d = 8.51, p < 0.001), muscle cross-sectional area (d = 7.91, p < 0.001), fiber cross-sectional area (d = 5.81, p < 0.001), fiber length (d = 7.86, p < 0.001) and fiber number (d = 4.62, p < 0.001). The thereafter performed experimental studies from our laboratory showed a range of trivial to large increases in maximum strength of 4.84% to 22.9% with d = 0.2 to 1.17 and ROM of 6.07% to 27.3% with d = 0.16 to 0.87 dependent on stretching time, training level and testing procedure. Furthermore, significant moderate to large magnitude hypertrophy effects of 7.29 to 15.3% with d = 0.53 to 0.84 in muscle thickness and trivial to small increases of 5.68% and 8.82% (d = 0.16 to 0.3) in muscle crosssectional area were demonstrated. The results are discussed based on physiological parameters from animal studies and in the front of knowledge in resistance training, suggesting mechanical tension to be one important factor to induce muscle hypertrophy and maximal strength increases. Further explanatory approaches such as hypoxia and changes in the muscle tendon unit are debated in the following. Since these studies are the first investigations on long-lasting stretch-mediated hypertrophy in humans, further research is needed to explore the underlying mechanisms and confirm the results in different populations to enhance the practical applicability for example in clinical populations when, e.g. counteracting muscular imbalances or sarcopenia in the elderly.

The food and land use system is one of the most important global economic sectors. At the same time, today's resource-intensive agricultural practices and the profit orientation in the food value chain lead to a loss of biological diversity and ecosystem services, high emissions, and social inequality – so-called negative externalities. From a scientific perspective, there is a broad consensus on the need to transform the current food system. This paper investigates the suitability of True Cost Accounting (TCA) as an approach to inte-grating positive and negative externalities into business decisions in the food and land use system, focusing on the retail sector due to its high market power and resulting influence on externalities along the entire food value chain. For this purpose, a qualitative study was con-ducted with sustainability managers of leading European food retail companies in terms of their annual turnover, sustainable finance experts, and political actors related to environmental and social policy. A sample of N=11 participants was interviewed about the emergence and meas-urement of externalities along the food value chain, the current and future relevance of knowing about externalities for food retail companies, and the market and policy framework necessary for the application of TCA. The data collected was evaluated using the method of qualitative content analysis according to Mayring. Findings show that TCA is a suitable method for capturing positive and negative external ef-fects along the food value chain and thus also for meeting the growing social, political, and financial demands for its sustainable orientation. At the same time, there are still some chal-lenges in the application of TCA, both from a theoretical and a practical point of view. The main challenges at present are the lack of a standardised methodology, data availability, and key performance indicators. Due to the focus on prices, margins and competitors, food retail groups, in particular, emphasise the risk of revenue and profit losses as well as customer churn when applying TCA. Hence, the introduction of TCA in the food and land use system requires the development of measures that are socially acceptable, backed by legal frameworks and promote the scientific development of the methodology. This offers the opportunity to create a level playing field, apply the polluter-pays principle to the entire value chain and support science in developing appropriate indicators as well as a TCA database. Food retail companies can benefit from addressing TCA at an early stage by analysing their value chain to initiate change processes early, identify risk raw materials and products, reduce negative externalities through targeted measures, sensitise customers to the issue and thus differentiate themselves from competitors.

This cumulative dissertation "Corporate Social Responsibility (CSR) Communication: Four empirical studies on the German banking industry" presents how commercial banks in Germany communicate their ambitions and commitment regarding corporate responsibility - i.e., CSR. The results of the first article show that the quality of mandatory non-financial reporting needs to be improved and that certain characteristics (e.g., previous reporting experience, reporting format and standard) have a positive influence on reporting quality. The second article shows that the CSR reporting scope on bank websites also has room for improvement and that various banking characteristics such as size, capital market orientation, media visibility or public ownership have an influence on communication. The third article illustrates that credit institutions in Germany are increasingly using social media for CSR communication, but that CSR communication strategies differ (Facebook vs. Twitter). The fourth article discusses CSR communication using advertisements and shows that the conceptual design of advertisements should be in line with the credit institution's business model and is therefore beneficial.

Contemporary society is shaped by the idea that time is, above all, a scarce economic resource that must be used efficiently – “time is money” not to be wasted. Increasingly, however, scientific findings suggest that such a way of perceiving of time seems a major cause of the current global climate and sustainability crisis. So far, this research has often focused on mobility, energy consumption, or the structural conditions of the social organisation of time. Considerably less work has been carried out in relation to the role of individual time-related needs regarding unsustainable consumption behaviour, although consumer research has been addressing needs-oriented approaches to sustainable consumption for a long time. Environmental and Sustainability Education (ESE) is considered an essential strategy to achieve the global sustainability goals of Agenda 2030. Internationally, as well as on a national level, ESE is increasingly mainstreamed in educational curricula and practice, including in Germany. Given the relation between time, needs and sustainability, it appears valuable to inquire into this field from the perspective of ESE – where time as a resource for sustainability has received comparatively little attention so far. The core research interest of this cumulative dissertation is therefore the question of how the connection between time, our needs and sustainability can be conveyed through pedagogical approaches. The inquiry used an exploratory, qualitative research design to address this question. In a first step, the concept of sustainability-related time use competence was developed. This then served as a guiding concept for the understanding of time used in this work and as the overall objective for the educational intervention developed and piloted as part of the research. Next, a content analysis of German curricula was conducted with the aim of determining whether and to what extent these address the relation between time and sustainability. The results show curricula contain only a few starting points that encourage a connection between time and sustainability in school lessons. The study further indicates that an understanding of time as a scarce resource to be used efficiently has prevailed in school contexts so far. Accordingly, pedagogical approaches to time often focus heavily on time management. The next step involved developing and piloting a time use competence curriculum in cooperation with three partner schools, using an Action Research Approach. This intervention followed the pedagogical approach of Self-Inquiry Based Learning (SIBL) seeking to sensitise learners to the relation between individual needs and consumer behaviour. During implementation, which lasted one semester, students logged their time, were encouraged to reflect on their personal needs, and subsequently implement individual change projects related to time use. This was embedded in continuous reflective individual and group exercises. The results strengthen the hypothesis that there is a relation between time use and sustainability. Furthermore, the pedagogical approach of SIBL has proven suitable to enable students to reflect on their time use and to raise their awareness of the role of individual needs. Participants reported that changes in time use did indeed increase their personal well-being. This, according to existing evidence from sustainability science, has been found to potentially lead to more sustainable behaviour. At the same time, previous research found that behavioural changes that lead to an increase in well-being do not automatically lead to more sustainable consumption behaviour. Rather, personal attitudes and motivation regarding sustainability are important. This suggests that future ESE interventions aiming at changes in time use should always also contain sufficient opportunities for reflection of values and motives. A third empirical study was carried out, inquiring into students’ time use during the eriod of COVID-19-induced school closures, using a Grounded Theory Approach. Since the pandemic disrupted young peoples’ routines drastically, the research focused on which kinds of learning experiences students made during this time and which insights can be derived for ESE. The results of the semi-structured interviews with 69 participants show first that the narrative of students’ learning loss, which is predominant in the current educational science, policy, and media discussion, falls short. Instead, a variety of learning experiences are revealed, such as learning one’s own learning and everyday rhythms or creatively adapting consumption habits to the new situation of “lockdown”. Overall, a key finding of this work is that students are currently unable to adequately realise their time-related needs. In view of the findings from research on time and sustainability, one recommendation is therefore that everyday school life could give students more space to organise their time according to their needs. This might be done through pedagogical measures in the classroom, but would also require a stronger institutional anchoring, for example, within the framework of the Whole Institution Approach to Sustainability (WIA), to bring about lasting changes. Furthermore, it would be advisable to give the topic of time in connection with sustainability more space in curricula and in teacher training. This gives rise to future research needs, such as the need to explore how time use competence can be included into everyday pedagogical practice, for instance, by adapting the SIBL approach piloted in a school setting here. It would also call for longitudinal research designs, and it would be of interest to research how time use competence might be incorporated into school development processes. Given the ongoing debate about the impact of the COVID-19 pandemic on schools and education in general, the findings of the research can stimulate both further research and future ESE practice. The experiences during the pandemic have shown that schools and all actors involved including students and teachers, are so far insufficiently prepared to handle crises. Here, the approach to time use competence piloted in this work can offer valuable stimulations for ESE research and practice. This is especially true since it is compatible with existing approaches to key competencies for sustainability by seeking to complement them with a stronger focus on individual, needs-oriented time shaping.

Research questions In the study, predictive models for predicting therapy outcome are created using the dataset from E-COMPARED project (see section 4.1), which belongs to type 3 according to Table 1. These models aim to classify patients into two groups, improved and nonimproved. Since it is important to determine whether the models contribute to improvement of treatment, research questions that can contribute to the usage of type 3 models are established. The study focuses on the following three questions: 1. How accurately can the therapy outcome be predicted by various machine learning algorithms? Answering this question can let the people concerned obtain information about the reliability of contemporary predictive models. In addition, if the predictive power of the models is good, it is more likely to be used to assist therapists’ decisions. 2. Which kind of data is more important in predicting the therapy outcome? The answer to this question can show which dataset should be considered first to make better predictive models. Therefore, it can be helpful for researchers who want to make predictive models in the future and eventually help to facilitate personalized therapy. 3. What are the features with strong predictive power? The answer to this question can affect the people concerned, especially therapists. Therapists can use the most influential features revealed to adjust and improve future treatments.