OBJECTIVE: Measurement of exercise capacity is essential in patients with non-specific chronic low back pain (CLBP). However, the conventional Astrand bicycle test is not feasible in patients with a very poor aerobic capacity. Therefore the Astrand bicycles test for non-specific CLBP patients based on lean body mass (LBM) was developed as an alternative. The aim of this study was to evaluate reliability and validity of the LBM-based Astrand test.SUBJECTS: Twenty patients with non-specific CLBP and 20 healthy subjects were included for the reliability evaluation, and 19 healthy subjects for the validity evaluation.METHOD: Patients and healthy subjects were assessed twice. Intra class correlation (ICC), repeatability coefficient (RC) and the limits of agreement (LOA) were calculated as a measure of test re-tests reliability. An ICC >or= 0.75 was considered acceptable. Validity was tested by calculating ICC between the LBM-based Astrand test and a maximal bicycle test.RESULTS: The LBM-based Astrand test shows good reliability, reflected by an ICC >or= 0.91 and 95% of the 20 patients could perform the test. However, differences with the estimated true value reflected by the RC and natural variation reflected by the LOA were substantial in patients. Validity was good, reflected by ICC >or= 0.88.CONCLUSION: The present study shows that the LBM-based Astrand test is a reliable, valid, and feasible method for patients with non-specific CLBP. However, a substantial amount of variation should be taken into account in patients when interpreting the test results clinically.
OBJECTIVE: Measurement of exercise capacity is essential in patients with non-specific chronic low back pain (CLBP). However, the conventional Astrand bicycle test is not feasible in patients with a very poor aerobic capacity. Therefore the Astrand bicycles test for non-specific CLBP patients based on lean body mass (LBM) was developed as an alternative. The aim of this study was to evaluate reliability and validity of the LBM-based Astrand test.SUBJECTS: Twenty patients with non-specific CLBP and 20 healthy subjects were included for the reliability evaluation, and 19 healthy subjects for the validity evaluation.METHOD: Patients and healthy subjects were assessed twice. Intra class correlation (ICC), repeatability coefficient (RC) and the limits of agreement (LOA) were calculated as a measure of test re-tests reliability. An ICC >or= 0.75 was considered acceptable. Validity was tested by calculating ICC between the LBM-based Astrand test and a maximal bicycle test.RESULTS: The LBM-based Astrand test shows good reliability, reflected by an ICC >or= 0.91 and 95% of the 20 patients could perform the test. However, differences with the estimated true value reflected by the RC and natural variation reflected by the LOA were substantial in patients. Validity was good, reflected by ICC >or= 0.88.CONCLUSION: The present study shows that the LBM-based Astrand test is a reliable, valid, and feasible method for patients with non-specific CLBP. However, a substantial amount of variation should be taken into account in patients when interpreting the test results clinically.
Protein supplementation has shown to improve muscle mass in older adults. However, its effect may be influenced by supplementation dose, frequency and timing. This systematic review aimed to assess the effect of dose, frequency and timing of protein supplementation on muscle mass in older adults. Five databases were systematically searched from inception to 14 March 2023, for randomised controlled trials investigating the effect of protein supplementation on muscle mass in adults aged ≥65 years. Random effects meta-analyses were performed, stratified by population. Subgroups were created for dose (≥30 g, <30 g/day), frequency (once, twice, three times/day) and timing of supplementation (at breakfast, breakfast and lunch, breakfast and dinner, all meals, between meals). Heterogeneity within and between subgroups was assessed using I 2 and Cochran Q statistics respectively. Thirty-eight articles were included describing community-dwelling (28 articles, n=3204, 74.6±3.4 years, 62.8 % female), hospitalised (8 articles, n=590, 77.0±3.7 years, 50.3 % female) and institutionalised populations (2 articles, n=156, 85.7±1.2 years, 71.2 % female). Protein supplementation showed a positive effect on muscle mass in community-dwelling older adults (standardised mean difference 0.116; 95 % confidence interval 0.032–0.200 kg, p=0.007, I 2=15.3 %) but the effect did not differ between subgroups of dose, frequency and timing (Q=0.056, 0.569 and 3.084 respectively, p>0.05). Data including hospitalised and institutionalised populations were limited. Protein supplementation improves muscle mass in community-dwelling older adults, but its dose, frequency or timing does not significantly influence the effect.
MULTIFILE
In dit KIEM-project verkennen we de haalbaarheid van een nieuw concept voor energietransitie en circulaire economie: EnTranCe-for-a-Community. Dit is een generiek concept voor draagvlak voor lokale waarde-creatie en groene energieproductie. Na discussies met ons werkveld implementeren we EnTranCe-for-a-Community hier als een publiekskas met technologie om lokale biomassa om te zetten in groene energie (gas) en biocompost. We onderzoeken of dit concept een aantrekkelijke uitbreiding is voor lokale energie-initiatieven en energiecoöperaties (doorgaans bezig met zon en/of wind) als alternatief voor aardgas of een warmtenet. We willen weten of en hoe het realiseren van een EnTranCe-for-a-Community-project op een concrete locatie kansrijk is. Dat kansrijk zijn wordt op drie niveaus onderzocht: (a) de bijdrage aan de lokale energietransitie (kosten/baten); (b) de bijdrage aan een lokale circulaire economie door verwaarding van lokale biomassa (kosten/baten) en (c) de bijdrage aan draagvlak en enthousiasme (en dus praktische haalbaarheid) voor deze ontwikkelingen, door het nauw betrekken van lokale stakeholders bij de studie en eventuele implementatie. EnTranCe-for-a-Community combineert eerder opgedane kennis en kunde op een innovatieve manier en beoogt lokale energietransitie te verbreden naar lokale biomassa. Deze haalbaarheidsstudie wordt uitgevoerd door een nieuw samenwerkingsverband van partners uit de coöperatieve en lokale energiesector, MKB en het expertisecentrum EnTranCe van de Hanzehogeschool Groningen. Allen dragen bij aan de haalbaarheidsstudie met kennis, kunde en netwerken die nodig zijn voor dit onderzoek en voor realisatie op langere termijn, indien voldoende kansrijk. We gebruiken de beproefde iteratieve Lean Startup-aanpak, die juist is ontwikkeld voor dit type complexe en multidimensionale projecten. We gaan komen tot een business en een mission model voor eventuele toekomstige implementatie ergens in Groningen op basis van de gedocumenteerde kansrijkheid van het concept. Op die manier zal dit KIEM-project de basis leggen voor een veel groter projectvoorstel voor verdere realisatie.
The objective of Sustainable Solid Biofuel project is to contribute to a zero-waste and low-carbon emission production of charcoal by evaluating the feasibility and energy efficiency of three different conversion technologies. According to the IEA’s World Energy Outlook 2015 3 billion (more than a third of the global population) use solid biomass as wood, charcoal, or animal waste for cooking and heating1. Charcoal is one of the most widely used of the solid biofuels. In current charcoal production processes the gas stream from pyrolysis are mostly directly released to the environment which wastes energy and causes serious environmental pollution. However, the production of charcoal can be improved to be practiced on a sustainable basis by careful selection of wood or alternative biomass source as wood waste or agricultural residues and further focusing on harvesting strategy and production techniques. In the conversion process it is necessary to increase the energy efficiency while reducing emissions. Further sustainability can be increased by processing the smoke that is exhausted from the kiln, that correspond to roughly one third of the whole biomass. Within the volatile components in the smoke there are chemicals which can be used, for example, as industrial cleaners or wood preservatives and thus one of the environmental drawbacks of charcoal production can be eliminated and turned into another product input. Brazil is the world's largest charcoal producer2 consequently the state of the art of the recearch in this field can be found in Brazil. In this Sustainable Solid Biofuels project one of the leading universities of Brazil, the Universidade Federal de Viçosa (UFV) is joining forces with Avans University of Applied Sciences and two Dutch SMEs Privium B.V. and Charcotec B.V. to carry out the evaluation of the improvements that can be achieved in the energy efficiency.
