The understanding of mechanisms linking psychological stress to disease risk depend on reliable stress biomarkers. Circulating cell-free DNA (cfDNA) has emerged as a potential biomarker of cellular stress, aging, inflammatory processes, and cell death. Recent studies indicated that psychosocial stress and physical exercise might also influence its release. We compared the effects of acute psychosocial and physical exercise stress on cfDNA release by exposing 20 young, healthy men to both an acute psychosocial laboratory stressor and an acute physical exercise stressor. Venous blood and saliva samples were collected before and after stress exposure. Cell-free DNA was extracted from plasma and quantified by qPCR. Furthermore, cfDNA fragment length was analyzed and cfDNA methylation patterns were assayed across time. In addition, release of stress hormones and subjective stress responses were measured. Results showed a twofold increase of cfDNA after TSST and fivefold increase after exhaustive treadmill exercise, with an overabundance of shorter cfDNA fragments after physical exhaustion. Interestingly, cell-free mitochondrial DNA showed similar increase after both stress paradigms. Furthermore, cfDNA methylation signatures—used here as a marker for diverse cellular origin—were significantly different post stress tests. While DNA methylation decreased immediately after psychosocial stress, it increased after physical stress, suggesting different cellular sources of active DNA release. In summary, our results suggest stimulus and cell-specific regulation of cfDNA release. Whereas the functional role of stress-associated cfDNA release remains elusive, it might serve as a valuable biomarker in molecular stress research as a part of the psychophysiological stress response.

Background: The Kerlan-Jobe Orthopedic Clinic Shoulder and Elbow Score (KJOC) originally developed in English, assesses the functional status of the shoulder and elbow in overhead athletes. To date, no German version of the questionnaire exists. Objective: The aim of the study was to translate and to culturally adapt the KJOC into German (KJOC-G) and to test its psychometric properties. Methods: The first part of the study consisted of a translation and cross-cultural adaptation process which was performed in six stages according to international recommendations: Initial translations, synthesis, back translations, expert committee review, pretesting of the prefinal version, and final adaptations. Secondly, reliability, validity, and feasibility of the KJOC-G were assessed in German overhead athletes. Results: The translation and adaptation process led to minor alterations due to cultural differences while maintaining the general structure and content of the original score. A total of 152 overhead athletes (age 25.0 ± 6.6 years; 87 men/65 women) were included in the main analyses. The internal consistency (Cronbach's alpha = 0.93) and test-retest reliability (ICC 2.1 = 0.94) of the overall questionnaire were excellent. Moderate correlations with the German version of the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire (r = −0.51, p < .05) as well as the DASH-sports module (r = −0.54, p < .05) suggest moderate construct validity. Known-group method analysis showed the ability of the KJOC-G to discriminate between actively playing symptomatic (score: 71.2 ± 16.0) and asymptomatic (score: 93.1 ± 8.7) athletes. Conclusion: The KJOC-G score is valid, reliable, and suitable for assessing the functional shoulder and elbow status in German-speaking overhead athletes.

BackgroundSodium bicarbonate (NaHCO3) is an alkalizing agent and its ingestion is used to improve anaerobic performance. However, the influence of alkalizing nutrients on anaerobic exercise performance remains unclear. Therefore, the present study investigated the influence of an alkalizing versus acidizing diet on 400-m sprint performance, blood lactate, blood gas parameters, and urinary pH in moderately trained adults.MethodsIn a randomized crossover design, eleven recreationally active participants (8 men, 3 women) aged 26.0 ± 1.7 years performed one trial under each individual’s unmodified diet and subsequently two trials following either 4 days of an alkalizing (BASE) or acidizing (ACID) diet. Trials consisted of 400-m runs at intervals of 1 week on a tartan track in a randomized order.ResultsWe found a significantly lower 400-m performance time for the BASE trial (65.8 ± 7.2 s) compared with the ACID trial (67.3 ± 7.1 s; p = 0.026). In addition, responses were significantly higher following the BASE diet for blood lactate (BASE: 16.3 ± 2.7; ACID: 14.4 ± 2.1 mmol/L; p = 0.32) and urinary pH (BASE: 7.0 ± 0.7; ACID: 5.5 ± 0.7; p = 0.001).ConclusionsWe conclude that a short-term alkalizing diet may improve 400-m performance time in moderately trained participants. Additionally, we found higher blood lactate concentrations under the alkalizing diet, suggesting an enhanced blood or muscle buffer capacity. Thus, an alkalizing diet may be an easy and natural way to enhance 400-m sprint performance for athletes without the necessity of taking artificial dietary supplements.

Exercise training effectively mitigates aging-induced health and fitness impairments. Traditional training recommendations for the elderly focus separately on relevant physiological fitness domains, such as balance, flexibility, strength and endurance. Thus, a more holistic and functional training framework is needed. The proposed agility training concept integratively tackles spatial orientation, stop and go, balance and strength. The presented protocol aims at introducing a two-armed, one-year randomized controlled trial, evaluating the effects of this concept on neuromuscular, cardiovascular, cognitive and psychosocial health outcomes in healthy older adults. Eighty-five participants were enrolled in this ongoing trial. Seventy-nine participants completed baseline testing and were block-randomized to the agility training group or the inactive control group. All participants undergo pre- and post-testing with interim assessment after six months. The intervention group currently receives supervised, group-based agility training twice a week over one year, with progressively demanding perceptual, cognitive and physical exercises. Knee extension strength, reactive balance, dual task gait speed and the Agility Challenge for the Elderly (ACE) serve as primary endpoints and neuromuscular, cognitive, cardiovascular, and psychosocial meassures serve as surrogate secondary outcomes. Our protocol promotes a comprehensive exercise training concept for older adults, that might facilitate stakeholders in health and exercise to stimulate relevant health outcomes without relying on excessively time-consuming physical activity recommendations.

ZusammenfassungDie neuronale Kontrolle des Blutdrucks wird über das vegetative Nervensystem vermittelt. In diesem Beitrag werden physiologische und pathophysiologische Mechanismen rekapituliert. Aufgabe der Blutdruckregulation ist die Erhaltung eines adäquaten Herzzeitvolumens und eines ausreichenden Perfusionsdrucks für die Organe. Beim Glaukom ist der okuläre Perfusionsdruck als Differenz zwischen systemischem Blutdruck und intraokulärem Druck entscheidend für die Versorgung des Sehnervs. So sind Patienten mit Normaldruckglaukom und niedrig eingestelltem Blutdruck gefährdet, eine Progression ihres Glaukoms zu erleiden. Auch beim primären Offenwinkelglaukom spielt der systemische Blutdruck eine Rolle. Eine 24-Stunden-Blutdruckmessung mit besonderem Augenmerk auf das nächtliche Dipping des Blutdrucks ist für alle Glaukompatienten empfehlenswert. Internisten und Ophthalmologen sollten sich der gegenseitigen Beeinflussung beider Krankheitsbilder bewusst sein und diese in die Auswahl der individuellen Therapiestrategien und -ziele einbeziehen.