Johannes Kirsten

Dr. Johannes Kirsten

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
Verified
Journal Article
Open access
PDF file
JSJana Schellenberg
Jana Schellenberg
MAMagdalena Ahathaller
Magdalena Ahathaller
LMLynn Matits
Lynn Matits
JKJohannes Kirsten
Johannes Kirsten
JKJohannes Kersten
Johannes Kersten
Jürgen Michael SteinackerJürgen Michael Steinacker
Jürgen Michael Steinacker
Whether symptoms during COVID-19 contribute to impaired left ventricular (LV) function remains unclear. We determine LV global longitudinal strain (GLS) between athletes with a positive COVID-19 test (PCAt) and healthy control athletes (CON) and relate it to symptoms during COVID-19. GLS is determined in four-, two-, and three-chamber views and assessed offline by a blinded investigator in 88 PCAt (35% women) (training at least three times per week/>20 MET) and 52 CONs from the national or state squad (38% women) at a median of two months after COVID-19. The results show that the GLS is significantly lower (GLS −18.53 ± 1.94% vs. −19.94 ± 1.42%, p < 0.001) and diastolic function significantly reduces (E/A 1.54 ± 0.52 vs. 1.66 ± 0.43, p = 0.020; E/E′l 5.74 ± 1.74 vs. 5.22 ± 1.36, p = 0.024) in PCAt. There is no association between GLS and symptoms like resting or exertional dyspnea, palpitations, chest pain or increased resting heart rate. However, there is a trend toward a lower GLS in PCAt with subjectively perceived performance limitation (p = 0.054). A significantly lower GLS and diastolic function in PCAt compared with healthy peers may indicate mild myocardial dysfunction after COVID-19. However, the changes are within the normal range, so that clinical relevance is questionable. Further studies on the effect of lower GLS on performance parameters are necessary.

8 April 2021 in Cancers
Verified
Journal Article
Open access
PDF file
JKJohannes Kirsten
Johannes Kirsten
VWVerena Wais
Verena Wais
SSSebastian Schulz
Sebastian Schulz
ESElisa Sala
Elisa Sala
GTGunnar Treff
Gunnar Treff
Jürgen Michael SteinackerJürgen Michael Steinacker
Jürgen Michael Steinacker
Allogenic stem cell transplantation (aSCT) is the only potentially curative treatment for high-risk hematological diseases. Despite advancements in supportive measures, aSCT outcome is still affected by considerable transplant-related mortality. We implemented a new sarcopenia assessment prior to aSCT to evaluate its predictive capability for all-cause and non-relapse mortality. Therefore all patients initially scheduled for aSCT within a 25-month period were screened during pre-transplantation-routine for muscle mass, grip strength, and aerobic capacity (AC) by measuring peak oxygen uptake (VO2peak). Patients were assigned to one of five groups adapted according current sarcopenia guidelines. Primary endpoints were all-cause and non-relapse mortality within a follow up time of up to 12 months. A total of 178 patients were included and rated as normal (n = 48), impaired aerobic capacity (n = 56), pre-sarcopenic (n = 26), sarcopenic (n = 27), and severe sarcopenic (n = 22) without significant age-differences between groups. Patients presenting with sarcopenia showed a significant three-fold increase in all-cause and non-relapse mortality compared to patients with normal screening results. AC showed to be the strongest single predictor with a more than two-fold increase of mortality for low AC. We conclude that risk stratification based on combination of muscle mass, grip strength, and AC allowed identifying a subgroup with increased risk for complications in patients undergoing aSCT.

21 April 2023 in Biomedicines
Verified
Journal Article
Open access
PDF file
JKJohannes Kersten
Johannes Kersten
JSJana Schellenberg
Jana Schellenberg
AJAchim Jerg
Achim Jerg
JKJohannes Kirsten
Johannes Kirsten
HPHasema Persch
Hasema Persch
Jürgen Michael SteinackerJürgen Michael Steinacker
Jürgen Michael Steinacker
Speckle-tracking echocardiography (STE) has become an established, widely available diagnostic method in the past few years, making its value clear in cases of COVID-19 and the further course of the disease, including post-COVID syndrome. Since the beginning of the pandemic, many studies have been published on the use of STE in this condition, enabling, on the one hand, a better understanding of myocardial involvement in COVID-19 and, on the other, a better identification of risk to patients, although some questions remain unanswered in regard to specific pathomechanisms, especially in post-COVID patients. This review takes a closer look at current findings and potential future developments by summarising the extant data on the use of STE, with a focus on left and right ventricular longitudinal strain.

10 June 2020 in Cancers
Verified
Journal Article
Open access
PDF file
DBDaniel Alexander Bizjak
Daniel Alexander Bizjak
SSSebastian Schulz
Sebastian Schulz
USUwe Schumann
Uwe Schumann
SOStephanie Otto
Stephanie Otto
JKJohannes Kirsten
Johannes Kirsten
Jürgen Michael SteinackerJürgen Michael Steinacker
Jürgen Michael Steinacker
Based on growing evidence that breast cancer (BRCA) also plays a pivotal role in the regulation of skeletal muscle metabolism and the response to anti-oxidative stress, we examined the influence of regular exercise in human BRCA mutation carriers on their BRCA1 gene/protein expression and inflammatory/oxidative response. Sixteen BRCA-mutation carriers were assigned to an intervention (IG) or control group (CG). IG received a combination of high-intensity interval endurance (HIT) and strength training (HIRT) for six weeks, whereas CG received a low-intensity activity program. Before (T0) and at the end of the intervention (T1), muscle biopsy, physiological performance, blood withdrawal and anthropometry were obtained. Parameters included: Muscle BRCA1 gene/protein expression, inflammatory/oxidative stress, anti-oxidative capacity, peak oxygen capacity (VO2peak) and 1-repetition maximum (1-RM) at six different training machines. VO2peak and 1-RM of IG were increased at T1 compared to T0, whereas CG performance, physiological and molecular parameters remained unchanged. IG showed increased BRCA1 protein concentration as well as anti-oxidative capacity, whereas gene expression was unaltered. IG inflammatory and oxidative damage did not differ between time points. Combined HIT/HIRT increases aerobic and strength performance of BRCA-mutation carriers with up regulated BRCA1 protein expression and improved anti-oxidative status without showing an increased inflammatory response.

20 May 2025 in BMC Sports Science, Medicine and Rehabilitation
Verified
Journal Article
Open access
AHAlexander-Stephan Henze
Alexander-Stephan Henze
JBJakob Burger
Jakob Burger
LMLynn Matits
Lynn Matits
HDHannes Degenhardt
Hannes Degenhardt
KFKai Fehske
Kai Fehske
SSSebastian Schulz
Sebastian Schulz
Background: Athlete monitoring is becoming increasingly important in elite team sports to optimize performance and prevent injuries and other athletic health problems. A variety of objective and subjective measures are available to monitor external and internal load, well-being, and readiness to train or compete. A comprehensive Athlete Monitoring System (AMS) should include a meaningful combination of these methods and provide analysis and graphical presentation with decision support for coaches. The selection of monitoring methods to establish an AMS is influenced not only by sport-specific considerations, but also by the resources available. Our study aimed to describe the current practice of athlete monitoring in professional handball, and to examine potential gender differences. Methods: A total of 104 women’s (n = 44) and men’s (n = 60) handball teams competing in the first two national leagues in Germany and Switzerland were invited to participate in an online survey (May-August 2024). The questionnaire used for this cross-sectional study was designed by an interdisciplinary team and consisted of a maximum of 28 questions. The Mann-Whitney U test was used to test for gender differences on the extent of athlete monitoring in the following sub-areas: Injuries and illness surveillance (IIS); external and internal load; well-being and readiness. Results: The minimum response rate was 34.6% (19 men’s teams, 17 women’s teams). An IIS was performed in 75.0% of the responding teams. A total of 19 teams (52.8%) conducted further athlete monitoring, in 84.2% of cases with a comprehensive AMS, which most commonly included player tracking (13 out of 15 teams using external load measures) and the Session-Rating of Perceived Exertion-method (11 out of 19 teams using internal load measures), and customized well-being questionnaires (10 out of 18 teams using well-being measures). Men’s teams engage in significantly more IIS (94.7% men’s teams vs. 52.9% women’s teams, p =.019, δ = –0.356), player tracking (52.6% men’s teams vs. 11.8% women’s teams, p =.003, δ = –0.415) and internal load monitoring (63.2% men’s teams vs. 29.4% women’s teams, p =.015, δ = –0.387). Notably, 88.9% of teams are interested in implementing or developing an AMS. Conclusions: Our findings indicate that the majority of handball teams already use some form of IIS, and more than half of these teams have implemented an AMS, with men’s teams using significantly more player tracking, internal load and well-being measures. The apparent high level of interest in athlete monitoring highlights the importance of data-driven approaches to managing player health and performance, although selection bias must be considered. This information is valuable for practitioners seeking to implement or expand AMS in handball.

4 December 2025 in Nutrients
Verified
Journal Article
Open access
PDF file
LJLucas John
Lucas John
MMMoritz Munk
Moritz Munk
RBRoman Bizjak
Roman Bizjak
SSSebastian Schulz
Sebastian Schulz
JWJens Witzel
Jens Witzel
DBDaniel Alexander Bizjak
Daniel Alexander Bizjak
Background: Ultramarathon running represents an extreme physiological and metabolic challenge. Despite its growing popularity among recreational and competitive runners, evidence-based guidance for nutrition, energy balance, and recovery remains limited. Understanding metabolic response and hormonal regulation during such events is crucial for improving athletes’ health and performance. Methods: This prospective observational study examined participants of the 2024 TorTour de Ruhr® (100 km, 160.9 km, and 230 km). Pre- and post-race assessments included body composition, energy intake and expenditure, metabolic and hormonal biomarkers (leptin, ghrelin, insulin, glucagon, irisin, creatine kinase muscle type (CKM), lactate dehydrogenase (LDH)), and continuous glucose monitoring (CGM). Blood and saliva samples, bioimpedance analysis, and validated symptom questionnaires (General Assessment of Side Effects (GASE)) were used. Results: Of the 43 ultra runners (16 women, 27 men), 39 finished the race: 19 participants of the 100 km group, 8 of the 160.9 km group, and 16 of the 230 km group. Mean energy deficit was 6797 kcal (range: 417–18,364 kcal) with carbohydrate-dominant fueling (79%). Significant reductions in leptin and insulin and increases in ghrelin, glucagon, CKM, and LDH were observed, indicating disrupted energy homeostasis and muscle damage. The 230 km subgroup showed the greatest changes. Gastrointestinal and musculoskeletal symptoms increased post-race, aligning with biomarker patterns. Conclusions: Ultramarathon participation induces profound disturbances in metabolic and structural integrity, regardless of race distance. These findings underline the importance of developing individualized nutritional and recovery strategies and highlight the need for future research to investigate how energy deficit and macronutrient composition interact to influence metabolic strain and post-race recovery.