Problem solving patterns in design science research - Learning from engineering

Inactivity is the most widespread health risk factor in modern societies today, causing not only individual health problems but also immense costs for the healthcare systems. This emphasizes the need for improving population-wide impact of activity interventions, with particular attention to costeffectiveness, scalability, and delivery channels. In this paper, we present the theory-motivated design (drawing on the transtheoretical model) and empirical test of an IT-based physical activity programme (Personal Health Manager, PHM). In order to be as cost-effective as possible, the PHM was designed to have only few face-to-face contacts and to deliver supervision through the internet. Our design and implementation proved to be successful in a pilot test with 88 employees of an automotive company. The PHM increased participants’ activity, motivational readiness for change, functional capacity and transported the feeling of being well taken care of. Enhanced supervision did not increase performance. The results are first evidence that internet-mediated supervision can be successful in promoting physical activity and provide a starting point for investigating the role of faceto-face-contact and service levels in physical activity programs. The PHM and similar designs are also relevant to practice as the semi-automation makes them eligible for large-scale corporate or public health programs

Baseline and exercise predictors of VO2peak in systolic heart failure patients : Results from SMARTEX-HF

Author's accepted version (postprint).This is an Accepted Manuscript of an article published by American College of Sports Medicine in Medicine & Science in Sports & Exercise on 04/11/2019.Available online: https://journals.lww.com/acsm-msse/FullText/2020/04000/Baseline_and_Exercise_Predictors_of_V_O2peak_in.5.aspxacceptedVersio

Online, set, go - Design and empirical test of an IT-based physical activity intervention

Inactivity is the most widespread health risk factor in modern societies today, causing not only individual health problems but also immense costs for the healthcare systems. This emphasizes the need for improving population-wide impact of activity interventions, with particular attention to costeffectiveness, scalability, and delivery channels. In this paper, we present the theory-motivated design (drawing on the transtheoretical model) and empirical test of an IT-based physical activity programme (Personal Health Manager, PHM). In order to be as cost-effective as possible, the PHM was designed to have only few face-to-face contacts and to deliver supervision through the internet. Our design and implementation proved to be successful in a pilot test with 88 employees of an automotive company. The PHM increased participants’ activity, motivational readiness for change, functional capacity and transported the feeling of being well taken care of. Enhanced supervision did not increase performance. The results are first evidence that internet-mediated supervision can be successful in promoting physical activity and provide a starting point for investigating the role of faceto-face-contact and service levels in physical activity programs. The PHM and similar designs are also relevant to practice as the semi-automation makes them eligible for large-scale corporate or public health programs

Acute and chronic effects of marathon running on the retinal microcirculation

Previous studies indicate an association between marathon running and premature atherosclerosis. Retinal vessel diameter alterations, in particular narrower arterioles and wider venules, reflect early stages of atherosclerosis, but the influence of marathon on the retinal microcirculation is unknown.; Retinal vessel diameters were measured in 85 male runners (age 31-60 years; previous marathons 0-56) and in 45 age-matched healthy controls using a static vessel analyzer. In runners, diameters were also measured immediately and 24h after a marathon. Cardiovascular risk profiles, clinical chemistry and, in a subgroup of 46 runners, peripheral arterial wave reflections were also assessed.; Runners had larger arterioles (median 196 μm (IQR 25) vs. 190(25); p = 0.068) and smaller venules (222(25) vs. 224(18); p = 0.063) than controls, resulting in a significantly increased arteriolar-to-venular ratio (AVR; 0.89(0.08) vs. 0.85(0.07); p < 0.001). In runners, retinal vessel diameters were not associated with body mass index, blood pressure, smoking, lipids or training history, and no differences were observed between the lowest (0.71-0.84) and highest (0.95-1.06) AVR quintiles. The marathon run induced a significant increase of AVR (0.91 (0.09); p = 0.007) due to larger arteriolar than venular dilatations, correlating weakly to race duration (r = 0.32; p = 0.003) and to a lower increase in leucocytes (r = -0.35; p = 0.001). Vessel diameters normalized 24h after the race. Augmentation index and pulse pressure decreased significantly after the race, but no associations with retinal vessel diameters were observed.; Marathon running is not associated with an impairment of the retinal microcirculation. These findings contrast previous reports on atherosclerotic alterations of peripheral vessels

The early repolarization pattern: Echocardiographic characteristics in elite athletes

Background The electrocardiographic early repolarization (ER) pattern is associated with idiopathic ventricular fibrillation and increased long-term cardiovascular mortality. Whether structural cardiac aberrations influence the phenotype is unclear. Since ER is particularly common in athletes, we evaluated its prevalence and investigated predisposing echocardiographic characteristics and cardiopulmonary exercise capacity in a cohort of elite athletes. Methods A total of 623 elite athletes (age 21 +/- 5 years) were examined during annual preparticipation screening from 2006 until 2012 including electrocardiography, echocardiography, and exercise testing. ECGs were analyzed with focus on ER. All athletes participated in a clinical follow-up. Results The prevalence of ER was 17% (108/623). ER-positive athletes were predominantly male (71%, 77/108), showed a lower heart rate (57.1 +/- 9.3 bpm versus 60.0 +/- 11.2 bpm; p = 0.015) and a higher lean body mass compared to ER-negative participants (88.1% +/- 5.6% versus 86.5% +/- 6.3%; p = 0.015). Echocardiographic measurements and cardiopulmonary exercise capacity in male and female athletes with and without ER largely showed similar results. Only the notching ER subtype (n = 15) was associated with an increased left atrial diameter (OR 7.01, 95%CI 1.65-29.83; p = 0.008), a higher left ventricular mass (OR 1.02, 95%CI 1.00-1.03; p = 0.038) and larger relative heart volume (OR 1.01, 95%CI 1.00-1.01; p = 0.01). During a follow-up of 7.4 +/- 1.5 years, no severe cardiovascular event occurred in the study sample. Conclusions In elite athletes presence of ER is not associated with distinct alterations in echocardiography and cardiopulmonary exercise. Athletes presenting with ER are rather male, lean with a low heart rate

Structural alterations of retinal arterioles in adults late after repair of aortic isthmic coarctation

Patients after coarctation repair still have an increased risk of cardiovascular or cerebrovascular events. This has been explained by the persisting hypertension and alterations in the peripheral vessels. However, involvement of the central vessels such as the retinal arteries is virtually unknown. A total of 34 patients after coarctation repair (22 men and 12 women; 23 to 58 years old, age range 0 to 32 years at surgical repair) and 34 nonhypertensive controls underwent structural and functional retinal vessel analysis. Using structural analysis, the vessel diameters were measured. Using functional analysis, the endothelium-dependent vessel dilation in response to flicker light stimulation was assessed. In the patients after coarctation repair, the retinal arteriolar diameter was significantly reduced compared to that of the controls (median 182 mum, first to third quartile 171 to 197; vs 197 microm, first to third quartile 193 to 206; p >0.001). These findings were independent of the peripheral blood pressure and age at intervention. No differences were found for venules. The functional analysis findings were not different between the patients and controls (maximum dilation 3.5%, first to third quartile 2.1% to 4.5% vs 3.6%, first to third quartile 2.2% to 4.3%; p = 0.81), indicating preserved autoregulative mechanisms. In conclusion, the retinal artery diameter is reduced in patients after coarctation repair, independent of their current blood pressure level and age at intervention. As a structural marker of chronic vessel damage associated with past, current, or future hypertension, retinal arteriolar narrowing has been linked to stroke incidence. These results indicate an involvement of cerebral microcirculation in aortic coarctation, despite timely repair, and might contribute to explain the increased rate of cerebrovascular events in such patients