[Influence of the contact restrictions against SARS-CoV-2 on physical activity among public sector employees.] / Einfluss der Kontaktbeschränkungen gegen SARS-CoV-2 auf die körperliche Aktivität von Beschäftigten des öffentlichen Dienstes.

Objective: Preliminary results from activity surveys conducted in spring 2020 suggest that athletic activity may have decreased within the contact restrictions against the spread of coronavirus. The coronavirus pandemic poses many challenges to the workforce in the healthcare system. Therefore, this study investigated whether the measures to limit the pandemic have an influence on the activity behavior of employees in the public sector. Method: A retrospective cross-sectional survey was conducted to collate the activity behavior among employees of three institutions in the public sector before and during the measures against the coronavirus in April 2020. An online version of the Freiburg Activity Questionnaire was used. Using Wilcoxon tests on connected samples with a significance level of p < 0.05, the activity behavior was examined for differences before compared to during the contact restrictions in min/week and MET-min./week. Results: A total of 1797 public sector employees in Freiburg (36.0% male, 63.9% female, and 0.1% diverse) participated in the survey. For sports activity, a relevant difference (p < 0.05) was measured in the medians (Mdn) of activities per week before (Mdn = 180 min) and during (Mdn = 120 min) the relevant contact restrictions. Similarly, for energy expenditure through exercise, the median value within the contact restrictions decreased from Mdn = 1022 MET-min/week to Mdn = 750 MET-min./week. Conclusion: Measures to limit the spread of the coronavirus have led to a reduction in activity levels among public sector employees. In particular, fewer employees engaged in sports. This could be related to the closure of fitness studios as these activities were particularly reduced. Decreased physical activity can lead to unfavorable individual risk profiles, which must be compensated for in the future.

Trends in the numbers of SARS-CoV-2 infections among students: a prospective cohort study comparing students in sports boarding schools with students in day schools during early COVID-19 pandemic.

Introduction: During the first months of the COVID pandemic it emerged that facilities where people gather or live together in cohorts, such as nursing homes or schools, were particularly at high risk for becoming hotspots of virus transmission. German political and health institutions responded with far-reaching interventions and preventive strategies to protect the population from infection with SARS-CoV-2. In this context, it remains unclear whether boarding schools for sports particularly pose a risk of infection to their residents. Methods: In a single-center prospective cohort study, numbers of SARS-CoV-2 infections of students in sports boarding schools (n = 11) vs. students attending regular day schools (n = 22) in the region Freiburg/Hochschwarzwald in Germany were investigated over a period from October 2020 to January 2021 via regular virus and antibody screening (German Clinical Trials Register; Study ID: DRKS00021909). In addition, individual and behavioral risk factors for infection were stratified via questionnaire, which provide an indication of cohort specific risk factors for infection and the success of the implementation of hygiene concepts, as well as other infection prevention strategies, within the respective facilities. Results: Regarding SARS-CoV-2 infection numbers, the screening detected no significant group difference between sports boarding schools vs. day schools. Discussion: The study results provide indications that sports boarding schools did not pose an increased risk of infection, assuming that the facilities prevent virus transmissions with appropriate preventive strategies and hygiene measures. In future pandemic scenarios larger-scale and multicenter studies are necessary to achieve more comprehensive epidemiological data in this field.

Physiology, power output, and racing strategy of a Race Across America finisher.

The Race Across America, a 4800-km nonstop cycle race, is one of the most demanding endurance sports events. We display the racing strategy, power output, HR, hormonal levels, and inflammatory markers of an athlete before and during the race, which he completed in 10 d 23 h.The athlete showed physiological characteristics of a well-trained (nonelite) cyclist (V˙O2peak=63 mL·min·kg, heart volume=11.3 mL·kg). The race was mainly performed at low intensities (mean ± SD: power output=141 ± 76 W, HR=117 ± 14 bpm). During the race, testosterone levels dropped initially by 30-40% and returned to baseline toward the end. Cortisol remained elevated throughout (+75%-90% compared with baseline). Markers of inflammation (C-reactive protein), dehydration, and protein catabolism (albumin) were not affected. The athlete used a race strategy with regular sleeping breaks (total rest=91 h, 45 h of sleep).Contrasting conventional racing strategies for the Race Across America, which aim at minimizing sleep and maximizing ride time, our case demonstrates that by emphasizing regular recovery and sleep, such alternative strategy might lead an equally successful race result.

Non-invasive ventilation applied for recovery from exercise-induced diaphragmatic fatigue.

BACKGROUND: Exercise-induced diaphragmatic fatigue (DF) is conventionally considered to reflect impaired diaphragm function resulting from load imposed on the diaphragm during exercise and is known to be reduced by the application of non-invasive ventilation (NIV) during heavy-intensity exercise testing (HEET). On that physiological condition NIV applied for diaphragm unloading during recovery from exercise should be capable of accelerating recovery from DF and therewith prolonging exercise time to exhaustion and limiting the development of DF during a subsequent HEET compared to recovery during spontaneous breathing. METHODS: Seven highly-trained subjects (V'O(2max) 62.7±7.8 ml/kg/min) performed four HEET at 85% V'O(2max) with 60 min of recovery during I spontaneous breathing and II NIV between two HEET. RESULTS: Twitch transdiaphragmatic pressure (TwPdi) during supramaximal magnetic phrenic nerve stimulation decreased (p<0.04) following first HEET and subsequently completely recovered (p>0.2) during I and II. Following second HEET TwPdi comparably decreased (I 0.24±0.21 vs II 0.32±0.29 kPa; p=0.17). Exercise time to exhaustion during second HEET was equal during I and II (I 514±49 vs II 511±92 s; p=0.88). CONCLUSIONS: In conclusion, NIV applied for diaphragm unloading during recovery following HEET does neither affect recovery from DF nor subsequent exercise performance thereby providing further evidence that DF might reflect post-exercise diaphragm shielding rather than impaired diaphragm function.

Unusual cause of exercise-induced ventricular fibrillation in a well-trained adult endurance athlete: a case report.

INTRODUCTION: The diseases responsible for sudden deaths in athletes differ considerably with regard to age. In young athletes, congenital malformations of the heart and/or vascular system cause the majority of deaths and can only be detected noninvasively by complex diagnostics. In contrast, in older athletes who die suddenly, atherosclerotic disease of the coronary arteries is mostly found. Reports of congenital coronary anomalies as a cause of sudden death in older athletes are rare. CASE PRESENTATION: A 48-year-old man who was a well-trained, long-distance runner collapsed at the finish of a half marathon because of a myocardial infarction with ventricular fibrillation. Coronary angiography showed an anomalous origin of the right coronary artery from the left sinus of Valsalva with minimal wall alterations. Multislice computed tomography of the coronary arteries confirmed these findings. Cardiomagnetic resonance imaging demonstrated a mild hypokinesia of the basal right- and left-ventricular posterior wall. An electrophysiological study showed an inducible temporary polymorphic ventricular tachycardia and an inducible ventricular fibrillation. The athlete was subsequently treated by acetylsalicylic acid 100 mg (0-1-0), bisoprolol 2.5 mg (1-0-0) and atorvastatin 10 mg (0-0-1) and was instructed to keep his training intensity under the 'individual anaerobic threshold'. Intense and long-lasting exercise under extreme environmental conditions, particularly heat, should also be avoided. CONCLUSION: This case report presents a coronary anomaly as the most likely reason for an exercise-induced myocardial infarction with ventricular fibrillation in a well-trained 48-year-old endurance athlete. Therefore, coronary anomalies have also to be considered as a possible cause of cardiac problems in older athletes.

Magnetic resonance imaging of the lumbar spine and blood volume in professional cyclists.

Stimulated hematopoiesis is observed in the bone marrow of endurance-trained athletes by magnetic resonance imaging (MRI) independent of the hemoglobin concentration (hematocrit or erythrocyte count) or circulating reticulocytes, but may be related to blood volume (BV). This study determined whether hyperplasia of hematopoietic bone marrow of professional cyclists correlates with their red cell volume (RCV). Twelve male professional cyclists (mean +/- SD; 20.2 +/- 1.4 years, 69.0 +/- 4.5 kg, VO2max 64.4 +/- 4.6 ml/min/kg, BV 7257 +/- 884 ml, RCV 2990 +/- 299 g) completed an MRI of the lumbar spine, a total BV determination using a CO-rebreathing method and a graded exercise testing within two consecutive days. Significant correlations were found between performance and BV data. A significant correlation existed also between the signal intensity of the Turbo inversion-recovery sequence with short inversion time (Turbo-STIR) and BV (r (2) = 0.47, P < 0.05), RCV (r (2) = 0.56, P < 0.05) and plasma volume (r (2) = 0.39, P < 0.05) per kilogram body mass. The present study provides evidence of stimulated erythropoiesis with hyperplasia of the hematopoietic bone marrow of endurance athletes explaining their large RCV.