Search

Background: Regular physical activity during childhood and adolescence is associated with health benefits. Consequently, numerous health promotion programs for children and adolescents emphasize the enhancement of physical activity. However, the ActivityStat hypothesis states that increases in physical activity in one domain are compensated for by decreasing physical activity in another domain. Currently, little is known about how physical activity varies in children and adolescents within intervals of one and multiple days. Objectives: This systematic review provides an overview of studies that analyze changes in (overall) physical activity, which are assessed with objective measurements, or compensatory mechanisms caused by increases or decreases in physical activity in a specific domain in children and adolescents.Methods: A systematic search of electronic databases (PubMed, Scopus, Web of Science, SportDiscus) was performed with a priori defined inclusion criteria. Two independent researchers screened the literature and identified and rated the methodological quality of the studies. Results: A total of 77 peer-reviewed articles were included that analyze compensatory mechanisms with multiple methodological approaches. Of 40,829 participants, 16,265 indicated compensation associated with physical activity. Subgroup analyses separated by study design, participants, measurement instrument, physical activity context, and intervention duration also showed mixed results toward indication of compensation. Quality assessment of the included studies revealed high quality (mean = 0.866).Conclusion: This review provides inconclusive results about compensation in relation to physical activity. A trend toward increased compensation in interventional studies and in interventions of longer duration can be observed. more...

Background Children’s independent mobility (CIM) is an important contributor to physical activity and health in children. However, in the last 20 years CIM has significantly decreased. To develop effective intervention programs to promote CIM, the impact of the environment on CIM must be identified. This review seeks to provide an overview of sex/gender-specific socio-ecological correlates of CIM. Methods A systematic literature search of five databases (PubMed, PsycInfo, Scopus, Medline, Web of Science) was conducted with a priori defined eligibility criteria and identified 1838 potential articles published between January 1990 and November 2017. Two independent reviewers screened the literature and identified and rated methodological quality of the studies. Related factors of CIM were summarized separately for CIM license (parental permission to travel independently) and CIM destination (destinations to which a child travels independently), and separately for boys and girls using a semi-quantitative method. Results Twenty-seven peer-reviewed journal articles were identified which examined the relationship between the social and physical environment and CIM. Only seven studies reported results divided by sex/gender. Most associations between the environment and CIM were found in the expected direction (positive or negative) or not associated at all. The social environment seemed to be more influential for ensuring CIM than the physical environment. Neighborhood safety, fear of crime and stranger, parental support, and perception of traffic were important social environmental factors influencing CIM, while car ownership, distance, and neighborhood design were relevant physical environmental attributes. Few studies examined sex/gender-related environmental correlates of independent mobility, and those findings were inconsistent. Conclusion The findings of this systematic review serve as suggestions for intervention programs to increase CIM and to identify future directions in research. To establish a robust comprehension of the impact of the social and physical environment on CIM, further sex/gender-sensitive studies using comparable measurements for CIM and environmental correlates are needed. Electronic supplementary material The online version of this article (10.1186/s12942-018-0145-9) contains supplementary material, which is available to authorized users. more...

Questionnaires to assess physical activity (PA) have served and continue to serve important purposes in both research and practical application as they capture the self-reported aggregation of the individual which is at times complemented with device-based measures. This paper presents an expert consensus on best practices and future directions regarding the use of PA questionnaires (PAQ). The expert panel discussions that informed this manuscript took place during the 2nd International Workshop of the Center for the Assessment of Physical Activity (CAPA), held in Karlsruhe, Germany in July of 2019. Practically, we recommend to identify already existing and published PAQs in order to address a specific research question. To facilitate this, a decision framework (decision guide aide) for selecting a PAQ, consisting of purpose, construct, measurement unit, recall period, population, setting, measurement quality, feasibility/ease of use, and resources is presented. These best practices are discussed to provide some standardization for the field. With regard to future research on PAQs, continued efforts to improve validity, reliability, and sensitivity to change; consider the recall period; incorporate information on or adapt for a specific cultural/ethnic/environmental context; and strategically combine PAQ with other PA assessment methods capitalizing on the advancement of technology, are needed. These recommended future directions are outlined in order to motivate and challenge researchers to continually improve the field of PAQ research. more...

Physical inactivity is a major but modifiable risk factor for morbidity and mortality. Regular physical activity has preventive and therapeutic effects on numerous diseases including neurological disorders. Therefore, it is desirable that physicians motivate their patients to increase their physical and sports activities and that they help them to overcome barriers to exercising. The present study is a survey of neurologists who are members of the German Neurological Society with their own practices; they were asked whether they advised their patients on the benefits of physical activity. Details on physician counseling on physical activity were obtained, such as the frequency of counseling, the neurological disorders considered by the practitioners to be worth the effort of counseling, and the barriers to exercise on the part of patients. More than 80 % of the participants who responded to the survey stated that they frequently provide their patients with advice on the preventive and therapeutic aspects of physical activity. Almost all of them recommended endurance sports; this was followed by Far Eastern types of sport such as tai chi or yoga (70 % of all physicians who advice sports activities). The frequency of counseling about physical activity significantly correlated to the physician's own sports activity. Frequency of counseling was reduced if the physician assessed the patients to be incapable of adopting and maintaining a lifestyle of habitual physical activity. Lack of time as well as an insufficient reimbursement of the counseling, however, did not significantly influence the frequency of counseling. The physician's own sports activity matched that of individuals with similar social status. Thus, a selection bias does not seem to be of importance regarding the results of the survey. However, since only 169 of the 784 invited neurologists (21.6 %) responded to the questionnaire, the representativeness of the survey may be limited. Counseling about physical activity seems to be an essential part of consultations in neurological practices. more...

The fire beetle, Melanophila acuminata (Coleoptera: Buprestidae), senses infrared radiation at wavelengths of 3 and 10–25 microns via specialized protein-containing sensilla. Although the protein denatures outside of a biological system, this detection mechanism has inspired our bottom-up approach to produce single zinc phosphide microwires via vapour transport for IR sensing. The Zn3P2 microwires were immobilized and electrical contact was made by dielectrophoresis. Photoconductivity measurements have been extended to the near IR range, spanning the Zn3P2 band gaps. Purity and integrity of the Zn3P2 microwires including infrared light scattering properties were confirmed by infrared transmission microscopy. This biomimetic microwire shows promise for infrared chip development. more...

AimA substantial proportion of children’s and adolescent’s physical activity takes place in organised sports clubs in Germany. The purpose of this study was to describe (1) the proportion of children and adolescents who are members of sports clubs and the amount of moderate to vigorous physical activity (MVPA) performed in these clubs, and to identify socio-demographic predictors of (2) membership and (3) the amount of MVPA in sports clubs in Germany.Subjects and methodsThe sample consisted of 4,529 boys (50.5 %) and girls (49.5 %) aged between 4 and 17 years (M = 11.3; SD = 4.1). MVPA was assessed by a questionnaire. Socioeconomic status, immigration background, and residential area were assessed using a parent questionnaire.Results52.0 % of the girls and 63.1 % of the boys were members in sports clubs who exercised on average for 4 h per week with moderate to high intensity. The logistic regression analyses showed that gender, socioeconomic status, migration background and residential area were significant predictors of membership in sports clubs. The amount of MVPA was only significantly predicted by age, gender and residential area.ConclusionThe results of this study imply that sports clubs have a high potential for implementation of strategies to increase general levels of physical activity. more...

Schlaganfalle sind in Industrienationen die dritthaufigste Todesursache. Hauptursache ist Arteriosklerose. Regelmasige korperliche Aktivitat beeinflusst verschiedene zerebrovaskulare Risikofaktoren gunstig (arterielle Hypertonie, Diabetes mellitus, Dyslipidamien, Adipositas) und beugt damit der Schlaganfallentstehung vor. Nach wie vor nicht generell akzeptiert ist ein direkter praventiver Effekt korperlicher Aktivitat unabhangig von diesen atherogenen Faktoren. Die vorliegende Ubersicht kommt anhand einer Meta-Analyse von prospektiven randomisierten Kohortenstudien zu dem Ergebnis, dass Hirninfarkte unabhangig von anderen Risikofaktoren bei korperlich aktiven Mannern um 27%, Hirnblutungen 40% seltener auftreten als bei inaktiven. Bei Frauen sind die Unterschiede geringer und erreichen das Signifikanzniveau nicht. Korperliche Aktivitat ist daher zumindest bei Mannern eine effektive, nebenwirkungsfreie und kostenarme Primarpravention von Schlaganfallen. more...

One hundred years after the first description of autologous fat transplantation, this technique is receiving renewed attention. Initially, critically reviewed by plastic surgery societies, particularly those in the United States, the transfer of autologous fat was recently addressed at the September 2009 annual meeting of the German Society of Plastic Reconstructive and Aesthetic Surgeons in Hannover. In this consensus meeting, the panel reviewed both the current status of autologous fat transfer as well as established data concerning this evolving practice. In Germany, autologous fat transplantation is regulated by the Law on Tissue Transfer and Processing (Gewebegesetz). In an effort to facilitate future comparisons it is mandatory to describe harvesting, processing and reinjection techniques in detail. The consensus panel concluded that fat should be harvested using low vacuum settings and then transplanted in thin layers (Evidence V). Quantification of transplanted fat can best be performed by MRI (Evidence level III). Limited clinical studies are available with only some reaching a level of evidence II. At present, risk associated with autologous fat transplantation is considered to be minor. Tumor induction by autologous fat grafting is not proven. New techniques like stem cell enriched fat grafts may offer new promise for the Plastic and Reconstructive Surgeon. more...

Purpose/background Keratinocyte transplantation after burn injury and in chronic wound treatment is a potentially useful method in clinical practice. As transfer of keratinocytes is easily monitored and gene expression is controllable by topical administration of inductors, keratinocyte cultures are an especially interesting medium for gene therapeutic approaches far above of wound healing applications. A major obstacle is the standardization of keratinocyte preparation and maintenance of pure proliferative cultures for clinical application. The best outcomes in previous protocols were obtained using fibroblasts as a feeder layer, a requirement for long-term expanded cultures. Cell expansion and a high purity of keratinocytes are prerequisites for clinical transfer studies. Here, we describe a human keratinocytes preparation method that allows cell proliferation and expansion in culture without a feeder layer. Materials and methods Human keratinocytes were prepared from skin biopsies and cultured on untreated plastic culture dishes using Waymouth medium the first days followed by a change to a commercially available serum-free keratinocyte medium. The cells were characterized morphologically followed by transfection. For positive selection, transfected cells were selected by the cotransfection system pMACS Kk and magnetic cell sorting. Results Transfection rates were determined by expression of GFP vector which were 35%. The usage of magnetic cell sorting resulted in positive selection of transfected cells. Positive cells were able to adhere and proliferate after the sorting procedure. High viability and expansion of plastic adherent keratinocytes was achieved allowing up to 5 passages without signs of senescence and the doubling times were 3-5 days. The cells displayed typical keratinocyte morphology and immunostaining confirmed high keratinocyte purity. The number of contaminating fibroblasts was low. Conclusion Here, we describe an efficient and inexpensive method for a standardized human keratinocyte isolation without the need of a fibroblast feeder layer. This protocol may facilitate the clinical application of cell based therapies in burn injuries or chronic wounds using keratinocytes. more...

BACKGROUND AND PURPOSE Reconstruction of tendon tissue is problematic in many cases. Since direct tendon suture is often impossible, major reconstruction with the use of free tendon transplants or tendon transposition is necessary. Important motor units often have to be sacrificed for reconstructive purposes. In this study we investigated whether long tendon-like substitutes can be fabricated in vitro from human mesenchymal stem cells (MSCs) and a collagen type I gel when cultured under cyclic stretching conditions. MATERIAL AND METHODS MSCs were obtained from bone marrow aspirates of the iliac crest. Cells were suspended in a collagen type I gel and polymerized in a glass-cylinder with defined size. The fabricated tendon substitutes underwent static stretching for 14 days followed by cyclic stretching for 21 days in a special manufactured bioreactor. Non-stretched substitutes served as a control. RESULTS Macroscopically the stretched tendon substitutes showed an increased opacity and a smoother surface structure compared to the non-stretched control. The stretched substitutes displayed more spindle-shaped, longitudinal orientated cells, a tendon-like organization of the collagen matrix, and a parallel organization of the collagen fibers when stained with Hematoxylin/Eosin and Elastica. CONCLUSION Long tendon substitutes could be fabricated from MSCs and a collagen type I gel by cyclic stretching and showed tendon-like parallel collagen fibers and spindle-shaped cells. The use of MSCs in combination with adequate scaffold materials has great therapeutic potential for the development of autologous transplantable tendon substitutes. more...

The Motorik-Modul (MoMo) Longitudinal Study aims to contribute to long-term improvement in the health of German children and adolescents by focusing on: (i) the development of physical fitness and physical activity (including period effects); (ii) the individual and physical/social environmental determinants of the development of physical fitness and physical activity; and (iii) the impact of physical fitness and physical activity on the development of physical and mental health. The MoMo Longitudinal Study began with a nationwide representative sample of 4529 children and adolescents who ranged in age from 4–17 years at the study baseline (2003–2006). The first survey wave of the MoMo Longitudinal Study was conducted between 2009 and 2012, with two subsequent survey waves to be conducted between 2014 and 2016 and 2018 and 2020, respectively. The MoMo Longitudinal Study includes a physical fitness test profile, a physical activity questionnaire, and subjective and objective measures of health from the German Health Interview and Examination Survey (KiGGS). Data access is provided on request (alexander.woll@kit.edu). For further information, including a complete list of publications please visit www.motorik-modul.de. more...

BACKGROUND AND PURPOSE The Vacuum Assisted Closure device (V.A.C.) is commonly used for the treatment of problematic wounds. Furthermore, wound fluid can be easily collected with this device for research purposes. However, there is inadequate information as to whether the measurement of biomoieties of importance to wound healing is affected by the exposure of wound fluid to V.A.C. components, namely Polyurethane-foam and tubing. This study is an attempt to evaluate whether exposure of wound fluid to either V.A.C.-components affects concentrations of transforming growth factor beta 1 (TGF-b1) in wound fluid. MATERIAL AND METHOD Wound fluid was gathered from five decubital ulcer patients using the foil-technique and was exposed to sterile pieces of the V.A.C. Polyurethane-foam, tubing material or nothing for zero, one or five hours. Saline served as control. The concentration of TGF-b1 was measured using sandwich-ELISA. The resulting data were analyzed using two-way ANOVA, Newman-Keuls and Bonferroni t-Test. RESULTS The concentration of TGF-b1 decreased significant in all three groups during the five hours of the experiment (p < 0.05). There was no significant decrease in TGF-b1 concentration at any time point in-between the groups. CONCLUSION From this study, we conclude that wound-fluid collected from the V.A.C.-device via the polyurethane-foam or tubing for purposes of analyzing concentrations of TGF-beta 1 should not be different from fluid collected using the foil technique. more...

Epidemiologic studies proved that regular physical activity reduces the risk of several diseases being accompanied by increased mortality. Examples are arterial hypertension, diabetes mellitus, the metabolic syndrome, the coronary heart syndrome und several carcinoma. Additionally, regular physical activity counteracts postmenopausal osteoporosis. About 10 % of all deaths worldwide are caused by physical inactivity. If all physically inactive those individuals in Germany would walk speedily at least 15 to 20 minutes every day, the average life expectancy would increase by about half a year. Regular physical activity increases the life expectancy by about 3 to 4 years after considering confounding factors. Regarding competitive sports up to now only non-controlled studies exist indicating at least aerobic competitive endurance sports resulting in increased life expectancy. However, in these studies confounding factors have not been taken into account. more...

Objective To assess the prevalence and socio-demographic correlates of walking and cycling to school in a nationwide representative cross-sectional sample of German adolescents. Methods A sample of 1828 German adolescents aged 11–17 years were examined between 2003 and 2006. Mode of commuting to school was assessed using a reliable self-report measure. Socioeconomic status, migration background and residential area were assessed as socio-demographic variables using a parent-report questionnaire. Results Overall, 19.4% of adolescents walked and 22.2% cycled to school. Compared to girls with high socioeconomic status, girls with low socioeconomic status were more likely to walk (OR = 1.89, 95% CI = 1.23–2.89). Migration background increased the chance of walking in girls (OR = 0.47, 95% CI = 0.32–0.70) and decreased the chance of cycling in boys (OR = 2.39, 95% CI = 1.35–4.24). Compared to living in cities, living in rural areas lowered the chance of walking (girls: OR = 0.29, 95% CI = 0.18–0.50; boys: OR = 0.54, 95% CI = 0.32–0.93) and cycling (girls: OR = 0.12, 95% CI = 0.06–0.24; boys: OR = 0.34, 95% CI = 0.21–0.56), and living in medium-sized towns increased the chance of cycling in girls (OR = 1.86, 95% CI = 1.24–2.78) and boys (OR = 1.75, 95% CI = 1.20–2.56), respectively. Conclusions In Germany many adolescents use motorised transportation. Socio-demographic variables were associated with mode of commuting. more...

Physical activity reduces many major mortality risk factors including arterial hypertension, diabetes mellitus type 2, dyslipidemia, coronary heart disease, stroke, and cancer. All-cause mortality is decreased by about 30% to 35% in physically active as compared to inactive subjects. The purpose of this paper was to synthesize the literature on life expectancy in relation to physical activity. A systematic PubMed search on life expectancy in physically active and inactive individuals was performed. In addition, articles comparing life expectancy of athletes compared to that of nonathletes were reviewed. Results of 13 studies describing eight different cohorts suggest that regular physical activity is associated with an increase of life expectancy by 0.4 to 6.9 years. Eleven studies included confounding risk factors for mortality and revealed an increase in life expectancy by 0.4 to 4.2 years with regular physical activity. Eleven case control studies on life expectancy in former athletes revealed consistently greater life expectancy in aerobic endurance athletes but inconsistent results for other athletes. None of these studies considered confounding risk factors for mortality. In conclusion, while regular physical activity increases life expectancy, it remains unclear if high-intensity sports activities further increase life expectancy. more...

In skeletal muscle sonography high echogenicities have proved to be of diagnostic value. The following study examines whether these echointensities are caused mainly by interstitial fat or fibrosis. Consequently, the echogenicities of 86 muscles, their diameters, and the thickness of subcutaneous fat layers superficial to these muscles were measured and compared for content of fat and connective tissue, which were assessed by morphometry and biochemical testing in the corresponding muscle biopsy samples. The results indicate that fat replacement constitutes the main cause of increased muscle echogenicity, whereas intramuscular fibrosis did not significantly affect the muscles' echogenicity. more...

Hintergrund: Schlaganfälle sind in Industrienationen die dritthäufigste Todesursache (> 10 % aller Todesfälle jenseits des 65. Lebensjahres). Hauptursache ist Arteriosklerose. Regelmäßige körperliche Aktivität reduziert den arteriellen Blutdruck und das Körpergewicht, verbessert den Glucose- und Lipidstoffwechsel und wirkt somit derEntwicklung arteriosklerotisch bedingter kardiovaskulärer Komplikationen, insbesondere Herzinfarkten, entgegen. Die vorliegende Übersicht geht der Frage nach, ob Bewegung auch einen präventiven Effekt auf die Entwicklung von Hirninfarkten und -blutungen hat.Methoden: Grundlage der Analyse sind 33 prospektive Kohorten- und 10 Fallkontrollstudien, in denen der Einfluss körperlicher Aktivität auf das Risiko, einen Schlaganfall zu erleiden oder daran zu sterben, untersucht wurde.Ergebnisse: Die Metaanalyse weist für alle Schlaganfallmodalitäten(Infarkte, Blutungen, nicht differenziert) eineRisikoreduktion durch körperliche Bewegung nach. Dasrelative Risiko (RR) eines Hirninfarktes oder dadurchbedingten Todes beträgt 0,75, für Hirnblutungen 0,67 und für undifferenzierte Schlaganfälle 0,71. Die Risikoreduktion ist jedoch nur für Männer statistisch signifikant. Die Fallkontrollstudien weisen für Männer und Frauen zusammen ein RR = 0,32 auf.Schlussfolgerungen: Regelmäßige körperliche Aktivität hat bei Männern in multivariaten Analysen unter Berücksichtigung weiterer vaskulärer Risikofaktoren eine eigenständige präventive Potenz für zerebrovaskuläre Ereignisse. Bei Frauen wird ein signifikanter Effekt nicht erreicht. more...

Muscular imaging (ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI)) is of increasing importance in the diagnosis of generalized neuromuscular disease (Reimers et al. 1988). more...