Exercise is one of the external factors associated with impairment of intestinal integrity, possibly leading to increased permeability and altered absorption. Here, we aimed to examine to what extent endurance exercise in the glycogen‐depleted state can affect intestinal permeability toward small molecules and protein‐derived peptides in relation to markers of intestinal function. Eleven well‐trained male volunteers (27 ± 4 years) ingested 40 g of casein protein and a lactulose/rhamnose (L/R) solution after an overnight fast in resting conditions (control) and after completing a dual – glycogen depletion and endurance – exercise protocol (first protocol execution). The entire procedure was repeated 1 week later (second protocol execution). Intestinal permeability was measured as L/R ratio in 5 h urine and 1 h plasma. Five‐hour urine excretion of betacasomorphin‐7 (BCM7), postprandial plasma amino acid levels, plasma fatty acid binding protein 2 (FABP‐2), serum pre‐haptoglobin 2 (preHP2), plasma glucagon‐like peptide 2 (GLP2), serum calprotectin, and dipeptidylpeptidase‐4 (DPP4) activity were studied as markers for excretion, intestinal functioning and recovery, inflammation, and BCM7 breakdown activity, respectively. BCM7 levels in urine were increased following the dual exercise protocol, in the first as well as the second protocol execution, whereas 1 h‐plasma L/R ratio was increased only following the first exercise protocol execution. FABP2, preHP2, and GLP2 were not changed after exercise, whereas calprotectin increased. Plasma citrulline levels following casein ingestion (iAUC) did not increase after exercise, as opposed to resting conditions. Endurance exercise in the glycogen depleted state resulted in a clear increase of BCM7 accumulation in urine, independent of DPP4 activity and intestinal permeability. Therefore, strenuous exercise could have an effect on the amount of food‐derived bioactive peptides crossing the epithelial barrier. The health consequence of increased passage needs more in depth studies.
Studies among people with dementia demonstrated that the sleep quality and rhythm improves significantly when people are exposed to ambient bright light. Since almost half of the healthy older people also indicate to suffer from chronic sleep disorders, the question arises whether ambient bright light can be beneficial to healthy older people. Particularly the effect on sleep/wake rhythm in relation to the exposure to natural light is the focus. It was hypothesised that the sleep quality would be worse in winter due to a lower daylight dose than in summer due to the lower illuminance and exposure duration. A field study was conducted to examine the relationship between daylight exposure and sleep quality in 14 healthy older adults living independently in their own dwellings in the Netherlands. All participants were asked to take part of the study both during the summer period as well as during the winter period. Therefore, they had to wear an actigraph for five consecutive days which measured sleep, activity and light exposure. Results confirmed that people were significantly longer exposed to high illumination levels (>1000 lx) in summer than in winter. Sleep quality measures, however, did not differ significantly between summer and winter. A significant, positive correlation was found between exposure duration to high illuminance from daylight during the day and the sleep efficiency the following night in summer, implying that being exposed to high illuminance for a longer time period has a positive effect on sleep efficiency for the individual data. There was also a tendency of less frequent napping in case of longer exposure duration to light for both seasons. Sleep quality does not differ between summer and winter but is related to the duration of the exposure to bright light the day prior to the night. CC-BY Original article at http://solarlits.com/jd/5-14 http://dx.doi.org/10.15627/jd.2018.2 https://www.dehaagsehogeschool.nl/onderzoek/lectoraten/details/urban-ageing#over-het-lectoraat
MULTIFILE
Introduction: Strenuous physical stress induces a range of physiological responses, the extent depending, among others, on the nature and severity of the exercise, a person’s training level and overall physical resilience. This principle can also be used in an experimental set-up by measuring time-dependent changes in biomarkers for physiological processes. In a previous report, we described the effects of workload delivered on a bicycle ergometer on intestinal functionality. As a follow-up, we here describe an analysis of the kinetics of various other biomarkers. Aim: To analyse the time-dependent changes of 34 markers for different metabolic and immunological processes, comparing four different exercise protocols and a rest protocol. Methods: After determining individual maximum workloads, 15 healthy male participants (20–35 years) started with a rest protocol and subsequently performed (in a cross-over design with 1-week wash-out) four exercise protocols of 1-h duration at different intensities: 70% Wmax in a hydrated and a mildly dehydrated state, 50% Wmax and intermittent 85/55% Wmax in blocks of 2 min. Perceived exertion was monitored using the Borg’ Rating of Perceived Exertion scale. Blood samples were collected both before and during exercise, and at various timepoints up to 24 h afterward. Data was analyzed using a multilevel mixed linear model with multiple test correction. Results: Kinetic changes of various biomarkers were exercise-intensity-dependent. Biomarkers included parameters indicative of metabolic activity (e.g., creatinine, bicarbonate), immunological and hematological functionality (e.g., leukocytes, hemoglobin) and intestinal physiology (citrulline, intestinal fatty acid-binding protein, and zonulin). In general, responses to high intensity exercise of 70% Wmax and intermittent exercise i.e., 55/85% Wmax were more pronounced compared to exercise at 50% Wmax. Conclusion: High (70 and 55/85% Wmax) and moderate (50% Wmax) intensity exercise in a bicycle ergometer test produce different time-dependent changes in a broad range of parameters indicative of metabolic activity, immunological and hematological functionality and intestinal physiology. These parameters may be considered biomarkers of homeostatic resilience. Mild dehydration intensifies these time-related changes. Moderate intensity exercise of 50% Wmax shows sufficient physiological and immunological responses and can be employed to test the health condition of less fit individuals.
In this project on volunteering in LTH organisation we focus on three aims:1. To explain why organisations in different LTH sectors and regions had, have or need volunteers, how they interact with these volunteers, and the consequences (benefits and challenges) of volunteerism for these organisations.2. To determine how to find the right balance between paid and unpaid staff within the same organisation, considering the LTH sector and region they belong to, in order to create a healthy ecosystem within it (bearing in mind that no organisation can have both volunteers and paid staff do the same job - see above).3. To understand the perspectives, motives and expectations of why people (decide to) volunteer, how they interact with the organisation (management, paid staff) during volunteering, in order to interest them, recruit them, make use of them and retain them. In addition, it is also our aim to explain the benefits and challenges for people to volunteer.In this study, we will use an integrated approach, which implies that we aren’t only interested in the people- or organisation-side of volunteering (actor-side). We will also focus on the interactions between volunteers, paid staff and organisation during volunteering (core of the practice) in a certain LTH organisation, sector and region in the Netherlands (context-side). Studying volunteering in its specific contexts (organisation, sector, region) using an integrated practice approach, hasn’t been done before. In addition, as more and more LTH organisations in the Netherlands rely on volunteers (for their survival), either for economic, social or community (mienskip) reasons (context-related conditions), there is a need for a better understanding of volunteering (as indicated by aim 1-3). Finally, as not much literature has been based on Dutch studies about volunteering and the recruitment and retention of volunteers, this project will fill this gap.Besides the aims as outlined before, a more specific goal of this project is to provide recommendations for a sustainable business model for organisations to embrace volunteerism without affecting the structure of employees. In close cooperation with different LTH organisations, we will develop interventions as policy making instruments (and therefore also for the whole region where they are located). Furthermore, this research will contribute to industry, research (see also below), education (idem) and society. Our ultimate goal is to foster the wellbeing of the volunteers, paid staff and organisations and overall to contribute to social sustainability within The Netherlands.The above-mentioned aims and conceptual model lead to the following research question: How can volunteering in the LTH sectors in Dutch regions be shaped in a sustainable way for both volunteers as well as organisations?In line with what we discussed earlier, this also means contributing to a more stable labour market in hospitality, leisure and tourism in which voluntary work is recognised as an important and indispensable component of a healthy labour ecosystem.The approach we intend to adopt is a qualitative one based on narrative inquiry. While in the literature a quantitative approach using surveys to gather data is mostly used in understanding volunteerism and in measuring motives, we will observe and connect with the volunteers’ work in each sector/case identified and collect and analyse their individual stories. In addition, and in line with our integrated approach, we will investigate how the LTH organisations connected to these cases view the role, value and future of volunteerism.Societal IssueOur insights into volunteers’ work in different sectors will improve their quality of work by revealing drivers of their satisfaction, turnover, motivation, and passion. Managers can use these insights to train and retain volunteers as an integral part of not only their events, but the broader community. It is well-known that robust volunteering programmes are a cornerstone of contemporary social cohesion, and our findings will show how storytelling can strengthen these processes.Benefit to societyThis project will contribute in three ways to the LTH sector. The three outcomes of this study are first around a better understanding of what meaningful volunteering is, second, around the value of volunteers to LTH organisations, and, thirdly, about the value of such activities to Dutch society.The project will provide practical advice to LTH organisations on which interventions to use and in which contexts. This tangible output might take the form of a report, guide(s) mentioned above, and/or another instrument that suits the needs of managers and volunteers. The instrument(s) selected by LTH organisations and volunteers will help to disseminate best practices as well as to highlight the potential of volunteers and volunteering to wider society, other organisations and to current and potential volunteers. By following the steps in or using these instruments, we believe volunteer organisations will be better able to profile themselves and to recruit and retain volunteers.The present study will bring innovation in the field by generating new narratives on volunteerism, and by designing an engaging and appealing path for volunteers to join organisations. At the same time, it will design a structure for organisations to work with volunteers in a sustainable way.Consortium partners: Rodney Westerlaken, Geesje Duursma (both NHL Stenden, Leeuwarden)
