Personalized care in dilated cardiomyopathy: Rationale and study design of the activeDCM trial.

BACKGROUND: Dilated cardiomyopathy (DCM) is a leading cause of heart failure, particularly in younger individuals. Low physical strength is a global risk factor for cardiovascular mortality, and physical activity and a healthy lifestyle have been shown to improve outcomes in patients with heart failure. However, inappropriate exercise may increase the risk of arrhythmias in certain individuals with DCM. The determinants for predicting individual risks in this setting are poorly understood, and clinicians are hesitant to recommend sports for cardiomyopathy patients. The activeDCM trial aims to assess the safety and efficacy of a personalized exercise and activity programme for individuals with DCM. STUDY DESIGN: The activeDCM trial is a prospective, randomized, interventional trial with a 12 month follow-up. Three hundred patients, aged 18-75 years with DCM, left ventricular ejection fraction (LVEF) ≤ 50% and New York Heart Association (NYHA) classes I-III, will be enrolled. The intervention includes a personalized exercise and activity programme. The primary outcome is the increase in peak oxygen uptake (VO2max, mL/kg/min) from baseline to 12 months. Secondary endpoints include adherence to personalized activity programmes, freedom from clinically relevant arrhythmia, unplanned hospitalization for heart failure and changes in NYHA class, quality of life scores, 6 min walk distance, muscular strength, N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hsTnT) levels and cardiac function. Advanced research questions include high-density phenome and omics analysis combined with digital biomarkers derived from Apple Watch devices. DISCUSSION: The activeDCM trial will provide valuable insights into the safety and efficacy of personalized exercise training in DCM patients, inform clinical practice and contribute to the development of heart failure management programmes. The study will generate data on the impact of exercise on various aspects of cardiovascular disease, including genetic, metabolic, phenotypic and longitudinal aspects, facilitating the development of future digital tools and strategies, including the incorporation of smart wearable devices.

Iron deficiency in athletes: Prevalence and impact on VO2 peak.

BACKGROUND: Iron is an important micronutrient in pathways of energy production, adequate nutrient intake and its balance is essential for optimal athletic performance. However, large studies elucidating the impact of iron deficiency on athletes' performance are sparse. METHODS: Competitive athletes of any age who presented for preparticipation screening 04/2020-10/2021 were included in this study and stratified for iron deficiency (defined as ferritin level <20 µg/l with and without mild anemia [hemoglobin levels ≥11 g/dl]). Athletes with and without iron deficiency were compared and the impact of iron deficiency on athletic performance was investigated. RESULTS: Overall, 1190 athletes (mean age 21.9 ± 11.6 years; 34.2% females) were included in this study. Among these, 19.7% had iron deficiency. Patients with iron deficiency were younger (18.1 ± 8.4 vs. 22.8 ± 12.1 years, P < 0.001), more often females (64.5% vs. 26.8%, P < 0.001), had lower VO2 peak value (43.4 [38.5/47.5] vs. 45.6 [39.1/50.6]ml/min/kg, P = 0.022) and lower proportion of athletes reaching VO2 peak of >50 ml/min/kg (8.5% vs. 16.1%, P = 0.003). Female sex (OR 4.35 [95% CI 3.13-5.88], P > 0.001) was independently associated with increased risk for iron deficiency. In contrast, the risk for iron deficiency decreased by every life year (OR 0.97 [95% CI 0.95-0.99], P = 0.003). Iron deficiency was independently associated with reduced VO2 peak (OR 0.94 [0.91-0.97], P < 0.001) and lower probability to reach VO2 peak >50 ml/min/kg (OR 0.42 [95% CI 0.25-0.69], P = 0.001). CONCLUSIONS: Iron deficiency is common in athletes (predominantly in female and in young athletes). Iron deficiency was independently associated with reduced VO2 peak during exercise testing and lower probability to reach a VO2 peak >50 ml/min/kg.

COVID-19 in Female and Male Athletes: Symptoms, Clinical Findings, Outcome, and Prolonged Exercise Intolerance-A Prospective, Observational, Multicenter Cohort Study (CoSmo-S).

BACKGROUND: An infection with SARS-CoV-2 can lead to a variety of symptoms and complications, which can impair athletic activity. OBJECTIVE: We aimed to assess the clinical symptom patterns, diagnostic findings, and the extent of impairment in sport practice in a large cohort of athletes infected with SARS-CoV-2, both initially after infection and at follow-up. Additionally, we investigated whether baseline factors that may contribute to reduced exercise tolerance at follow-up can be identified. METHODS: In this prospective, observational, multicenter study, we recruited German COVID elite-athletes (cEAs, n = 444) and COVID non-elite athletes (cNEAs, n = 481) who tested positive for SARS-CoV-2 by PCR (polymerase chain reaction test). Athletes from the federal squad with no evidence of SARS-CoV-2 infection served as healthy controls (EAcon, n = 501). Questionnaires were used to assess load and duration of infectious symptoms, other complaints, exercise tolerance, and duration of training interruption at baseline and at follow-up 6 months after baseline. Diagnostic tests conducted at baseline included resting and exercise electrocardiogram (ECG), echocardiography, spirometry, and blood analyses. RESULTS: Most acute and infection-related symptoms and other complaints were more prevalent in cNEA than in cEAs. Compared to cEAs, EAcon had a low symptom load. In cNEAs, female athletes had a higher prevalence of complaints such as palpitations, dizziness, chest pain, myalgia, sleeping disturbances, mood swings, and concentration problems compared to male athletes (p < 0.05). Until follow-up, leading symptoms were drop in performance, concentration problems, and dyspnea on exertion. Female athletes had significantly higher prevalence for symptoms until follow-up compared to male. Pathological findings in ECG, echocardiography, and spirometry, attributed to SARS-CoV-2 infection, were rare in infected athletes. Most athletes reported a training interruption between 2 and 4 weeks (cNEAs: 52.9%, cEAs: 52.4%), while more cNEAs (27.1%) compared to cEAs (5.1%) had a training interruption lasting more than 4 weeks (p < 0.001). At follow-up, 13.8% of cNEAs and 9.9% of cEAs (p = 0.24) reported their current exercise tolerance to be under 70% compared to pre-infection state. A persistent loss of exercise tolerance at follow-up was associated with persistent complaints at baseline, female sex, a longer break in training, and age > 38 years. Periodical dichotomization of the data set showed a higher prevalence of infectious symptoms such as cough, sore throat, and coryza in the second phase of the pandemic, while a number of neuropsychiatric symptoms as well as dyspnea on exertion were less frequent in this period. CONCLUSIONS: Compared to recreational athletes, elite athletes seem to be at lower risk of being or remaining symptomatic after SARS-CoV-2 infection. It remains to be determined whether persistent complaints after SARS-CoV-2 infection without evidence of accompanying organ damage may have a negative impact on further health and career in athletes. Identifying risk factors for an extended recovery period such as female sex and ongoing neuropsychological symptoms could help to identify athletes, who may require a more cautious approach to rebuilding their training regimen. TRIAL REGISTRATION NUMBER: DRKS00023717; 06.15.2021-retrospectively registered.

[New treatment methods in competitive sports : What can we learn from the medical care of top athletes?] / Neue Therapieverfahren im Wettkampfsport : Was können wir aus der Betreuung von Spitzensportlern lernen?

BACKGROUND: As elite sport becomes more professional, the medical-psychological care of athletes is an important factor in providing them with the best possible support and thus optimising their performance. Our experience in the fields of prevention, conservative and surgical treatment, and rehabilitation also provides valuable insights for the treatment of our patients in daily practice. PREVENTION: Designed to improve static and dynamic muscle strength, kinaesthetic sensitivity, and neuromuscular control, the FIFA 11+ injury prevention programme is a three-part warm-up programme that is widely used in coaching and recreational sports. CONSERVATIVE TREATMENT: Platelet-rich plasma (PRP) is probably the most widely used orthobiologic treatment modality for the conservative management of tendon, muscle and cartilage injuries. Its effectiveness depends on the underlying pathology and the affected body region. The best evidence exists for the treatment of patellar tendinitis ("jumper's knee") and epicondylitis humeri radialis ("tennis elbow"). SURGICAL TREATMENT: The treatment of ACL injuries in competitive athletes is challenging due to the high physical demands. Prompt surgical intervention, anatomical reconstruction and additional extra-articular stabilisation are associated with improved surgical outcomes. Graft selection must be individualised, adapted to the needs of the athletes and our patients. REHABILITATION: Electromyography (EMG) is a diagnostic tool to identify muscular imbalances in rehabilitation and, at the same time, to help reduce them through biofeedback training. COGNITIVE TRAINING: Training for the development of basic cognitive skills helps to optimise performance through its potentially positive influence on the executive functions of athletes.

Targeted Metabolomics in High Performance Sports: Differences between the Resting Metabolic Profile of Endurance- and Strength-Trained Athletes in Comparison with Sedentary Subjects over the Course of a Training Year.

Little is known about the metabolic differences between endurance and strength athletes in comparison with sedentary subjects under controlled conditions and about variation of the metabolome throughout one year. We hypothesized that (1) the resting metabolic profile differs between sedentary subjects and athletes and between perennially endurance- and strength-trained athletes and (2) varies throughout one year of training. We performed quantitative, targeted metabolomics (Biocrates MxP® Quant 500, Biocrates Life Sciences AG, Innsbruck, Austria) in plasma samples at rest in three groups of male adults, 12 strength-trained (weightlifters, 20 ± 3 years), 10 endurance-trained athletes (runners, 24 ± 3 years), and 12 sedentary subjects (25 ± 4 years) at the end of three training phases (regeneration, preparation, and competition) within one training year. Performance and anthropometric data showed significant (p < 0.05) differences between the groups. Metabolomic analysis revealed different resting metabolic profiles between the groups with acetylcarnitines, di- and triacylglycerols, and glycerophospho- and sphingolipids, as well as several amino acids as the most robust metabolites. Furthermore, we observed changes in free carnitine and 3-methylhistidine in strength-trained athletes throughout the training year. Regular endurance or strength training induces changes in the concentration of several metabolites associated with adaptations of the mitochondrial energy and glycolytic metabolism with concomitant changes in amino acid metabolism and cell signaling.

Former SARS-CoV-2 Infection Was Related to Decreased VO2 Peak and Exercise Hypertension in Athletes.

The impact of former COVID-19 infection on the performance of athletes is not fully understood. We aimed to identify differences in athletes with and without former COVID-19 infections. Competitive athletes who presented for preparticipation screening between April 2020 and October 2021 were included in this study, stratified for former COVID-19 infection, and compared. Overall, 1200 athletes (mean age 21.9 ± 11.6 years; 34.3% females) were included in this study from April 2020 to October 2021. Among these, 158 (13.1%) athletes previously had COVID-19 infection. Athletes with COVID-19 infection were older (23.4 ± 7.1 vs. 21.7 ± 12.1 years, p < 0.001) and more often of male sex (87.7% vs. 64.0%, p < 0.001). While systolic/diastolic blood pressure at rest was comparable between both groups, maximum systolic (190.0 [170.0/210.0] vs. 180.0 [160.0/205.0] mmHg, p = 0.007) and diastolic blood pressure (70.0 [65.0/75.0] vs. 70.0 [60.0/75.0] mmHg, p = 0.012) during the exercise test and frequency of exercise hypertension (54.2% vs. 37.8%, p < 0.001) were higher in athletes with COVID-19 infection. While former COVID-19 infection was not independently associated with higher blood pressure at rest and maximum blood pressure during exercise, former COVID-19 infection was related to exercise hypertension (OR 2.13 [95%CI 1.39-3.28], p < 0.001). VO2 peak was lower in athletes with compared to those without COVID-19 infection (43.4 [38.3/48.0] vs. 45.3 [39.1/50.6] mL/min/kg, p = 0.010). SARS-CoV-2 infection affected VO2 peak negatively (OR 0.94 [95%CI 0.91-0.97], p < 0.0019). In conclusion, former COVID-19 infection in athletes was accompanied by a higher frequency of exercise hypertension and reduced VO2 peak.

Exercise Hypertension in Athletes.

Background: An exaggerated blood pressure response (EBPR) during exercise testing is not well defined, and several blood pressure thresholds are used in different studies and recommended in different guidelines. Methods: Competitive athletes of any age without known arterial hypertension who presented for preparticipation screening were included in the present study and categorized for EBPR according to American Heart Association (AHA), European Society of Cardiology (ESC), and American College of Sports Medicine (ACSM) guidelines as well as the systolic blood pressure/MET slope method. Results: Overall, 1137 athletes (mean age 21 years; 34.7% females) without known arterial hypertension were included April 2020−October 2021. Among them, 19.6%, 15.0%, and 6.8% were diagnosed EBPR according to ESC, AHA, and ACSM guidelines, respectively. Left ventricular hypertrophy (LVH) was detected in 20.5% of the athletes and was approximately two-fold more frequent in athletes with EBPR than in those without. While EBPR according to AHA (OR 2.35 [95%CI 1.66−3.33], p < 0.001) and ACSM guidelines (OR 1.81 [95%CI 1.05−3.09], p = 0.031) was independently (of age and sex) associated with LVH, EBPR defined according to ESC guidelines (OR 1.49 [95%CI 1.00−2.23], p = 0.051) was not. In adult athletes, only AHA guidelines (OR 1.96 [95%CI 1.32−2.90], p = 0.001) and systolic blood pressure/MET slope method (OR 1.73 [95%CI 1.08−2.78], p = 0.023) were independently predictive for LVH. Conclusions: Diverging guidelines exist for the screening regarding EBPR. In competitive athletes, the prevalence of EBPR was highest when applying the ESC (19.6%) and lowest using the ACSM guidelines (6.8%). An association of EBPR with LVH in adult athletes, independently of age and sex, was only found when the AHA guideline or the systolic blood pressure/MET slope method was applied.

Impact of Resistance Exercise and Nutritional Endorsement on physical performance in patients with GvHD (IRENE-G study) - design and rational of a randomized controlled trial.

BACKGROUND: Graft-versus-host disease (GvHD) remains a major complication and limitation to successful allogeneic hematopoietic stem cell transplantation. Treatment of GvHD is challenging due to its heterogeneous nature of presentation, with steroids remaining the established first-line treatment. Long-term doses of systemic corticosteroids have many well-known side-effects including muscle atrophy. Despite the fact that reports in non-cancer clinical populations treated with glucocorticoids demonstrated that resistance training can reverse atrophy and weakness, no RCT has evaluated the potential of resistance training on preventing the disease- and treatment-induced loss of skeletal muscle mass and function in GvHD patients yet. In this context, ensuring adequate nutrition is important as protein deprivation may accelerate the wasting process. As GvHD patients are commonly found to be malnourished, nutritional medical care should be considered when investigating the effect of exercise in GvHD patients. Therefore, the aim of the present "Impact of Resistance Exercise and Nutritional Endorsement on physical performance in patients with GvHD" - Study (IRENE-G) is to evaluate the effects of resistance exercise in combination with nutritional endorsement on physical, nutritional and patient-reported outcomes in GvHD patients. METHODS: IRENE-G is a 24-week prospective interventional RCT. One hundred twelve participants will be randomly allocated (1:1) to one of two arms: resistance exercise and nutritional optimization (experimental) vs. nutritional optimization only (control). Participants in the experimental group will engage in a supervised, progressive moderate-to-high intensity resistance training that is consistent with exercise guidelines for cancer patients, while additionally receiving nutritional support/therapy. Subjects of the control group solely receive nutritional support/therapy based on individual needs. Participants will be assessed at baseline, at 8, 16, 24 weeks for physical performance and various physiological, nutritional and patient-reported outcomes. Follow-up will be 6 months after intervention completion. DISCUSSION: To our knowledge, this will be the first RCT to assess and compare the effects of a resistance intervention supplemented by nutritional support/therapy against nutritional support only on various health-related outcomes in GvHD patients. The study will contribute to our understanding of the value of exercise and nutritional endorsement in counteracting the negative consequences of GvHD and its treatment. TRIAL REGISTRATION: ClinicalTrials.gov : NCT05111834 . Registered 8 November 2021 - Retrospectively registered.

COVID-19 in German Competitive Sports: Protocol for a Prospective Multicenter Cohort Study (CoSmo-S).

Objective: It is unclear whether and to what extent COVID-19 infection poses health risks and a chronic impairment of performance in athletes. Identification of individual health risk is an important decision-making basis for managing the pandemic risk of infection with SARS-CoV-2 in sports and return to play (RTP). Methods: This study aims 1) to analyze the longitudinal rate of seroprevalence of SARS-CoV-2 in German athletes, 2) to assess health-related consequences in athletes infected with SARS-CoV-2, and 3) to reveal effects of the COVID-19 pandemic in general and of a cleared SARS-CoV-2 infection on exercise performance. CoSmo-S is a prospective observational multicenter study establishing two cohorts: 1) athletes diagnosed positive for COVID-19 (cohort 1) and 2) federal squad athletes who perform their annual sports medical preparticipation screening (cohort 2). Comprehensive diagnostics including physical examination, laboratory blood analyses and blood biobanking, resting and exercise electrocardiogram (ECG), echocardiography, spirometry and exercise testing added by questionnaires are conducted at baseline and follow-up. Results and Conclusion: We expect that the results obtained, will allow us to formulate recommendations regarding RTP on a more evidence-based level.

Eccentric Overload during Resistance Exercise: A Stimulus for Enhanced Satellite Cell Activation.

PURPOSE: This study aimed to assess if one bout of concentric/eccentric exercise with damaging eccentric overload (CON/ECC+) provides a sufficient stimulus to induce SC activation, proliferation, and differentiation. METHODS: Biopsies from the vastus lateralis muscle of recreationally active men were obtained in the rested condition and again from the contralateral leg 7 d after exhaustive concentric/eccentric (CON/ECC) (n = 15) or CON/ECC+ (n = 15) leg extension exercise and in a nonexercising control group (CG) (n = 10). Total SC number (Pax7+), activated (Pax7+/MyoD+), and differentiating (myogenin+) SCs, fiber type distribution, and myofibers expressing neonatal myosin heavy chain (MHCneo) were determined immunohistochemically. Creatine kinase and myoglobin were measured in venous blood. Isokinetic strength tests were repeatedly conducted. RESULTS: Significant increases in creatine kinase and myoglobin (P = 0.001) indicated myofiber damage, whereas maximal strength was not impaired. Only after CON/ECC+, SC content (P = 0.019) and SC related to type II fibers (P = 0.011) were significantly increased. A significant increase in the proportion of activated SCs occurred after CON/ECC+ only (P = 0.003), the increase being significantly (P < 0.05) different from the changes after CON/ECC and in CG. The number of differentiating SC and MHCneo remained unchanged. CONCLUSIONS: Eccentric overload during leg extension exercise induced significant SC activation, increases in SC content and in SC number related to type II myofibers. However, there were no signs of increased SC differentiation or formation of new myofibers.

Gene expression changes in vastus lateralis muscle after different strength training regimes during rehabilitation following anterior cruciate ligament reconstruction.

Impaired muscle regeneration has repeatedly been described after anterior cruciate ligament reconstruction (ACL-R). The results of recent studies provided some evidence for negative alterations in knee extensor muscles after ACL-R causing persisting strength deficits in spite of the regain of muscle mass. Accordingly, we observed that 12 weeks of concentric/eccentric quadriceps strength training with eccentric overload (CON/ECC+) induced a significantly greater hypertrophy of the atrophied quadriceps muscle after ACL-R than conventional concentric/eccentric quadriceps strength training (CON/ECC). However, strength deficits persisted and there was an unexpected increase in the proportion of slow type I fibers instead of the expected shift towards a faster muscle phenotype after CON/ECC+. In order to shed further light on muscle recovery after ACL-R, the steady-state levels of 84 marker mRNAs were analyzed in biopsies obtained from the vastus lateralis muscle of 31 subjects before and after 12 weeks of CON/ECC+ (n = 18) or CON/ECC strength training (n = 13) during rehabilitation after ACL-R using a custom RT2 Profiler PCR array. Significant (p < 0.05) changes were detected in the expression of 26 mRNAs, several of them involved in muscle wasting/atrophy. A different pattern with regard to the strength training mode was observed for 16 mRNAs, indicating an enhanced hypertrophic stimulus, mechanical sensing or fast contractility after CON/ECC+. The effects of the type of autograft (quadriceps, QUAD, n = 19, or semitendinosus tendon, SEMI, n = 12) were reflected in the lower expression of 6 mRNAs involved in skeletal muscle hypertrophy or contractility in QUAD. In conclusion, the greater hypertrophic stimulus and mechanical stress induced by CON/ECC+ and a beginning shift towards a faster muscle phenotype after CON/ECC+ might be indicated by significant gene expression changes as well as still ongoing muscle wasting processes and a negative impact of QUAD autograft.

Reliability and validity of a standardised ultrasound examination protocol to quantify vastus lateralis muscle.

OBJECTIVE: To evaluate the reliability and validity of a standardized ultrasound examination protocol for measuring vastus lateralis muscle size. DESIGN: Prospective cohort study. SUBJECTS: Sixteen staff members of the university hospital of Heidelberg. METHODS: Muscle thickness, cross-sectional area and subcutaneous adipose tissue thickness were measured at 3 standardized sites on the right and left vastus lateralis muscle. Ultrasound measurements were collected by 2 independent investigators on 2 different days and compared with magnetic resonance imaging measurements. RESULTS: Intraclass correlation coefficients (ICC) for intra- and inter-rater reliability showed very good closeness of agreement for all parameters (ICC = 0.929-0.994, p < 0.001). Muscle thickness and subcutaneous adipose tissue thickness ultrasound and magnetic resonance imaging measurements revealed good to very good closeness of agreement (ICC = 0.835-0.969, p < 0.001), whereas cross-sectional area showed only average closeness of agreement (ICC = 0.727, p < 0.001). A strong predictive positive correlation for ultrasound and magnetic resonance imaging-based measurements of cross-sectional area was found (R² = 0.793, p < 0.001). CONCLUSION: By standardization of an examination protocol, quantitative vastus lateralis muscle ultrasound proved to be a reliable method for assessing vastus lateralis muscle size. Furthermore, this protocol is valid for measuring muscle thickness and subcutaneous adipose tissue thickness, although there seems to be a systematic underestimation of cross-sectional area depending on subcutaneous adipose tissue thickness.

Reliability and reproducibility of sciatic nerve magnetization transfer imaging and T2 relaxometry.

OBJECTIVES: To assess the interreader and test-retest reliability of magnetization transfer imaging (MTI) and T2 relaxometry in sciatic nerve MR neurography (MRN). MATERIALS AND METHODS: In this prospective study, 21 healthy volunteers were examined three times on separate days by a standardized MRN protocol at 3 Tesla, consisting of an MTI sequence, a multi-echo T2 relaxometry sequence, and a high-resolution T2-weighted sequence. Magnetization transfer ratio (MTR), T2 relaxation time, and proton spin density (PSD) of the sciatic nerve were assessed by two independent observers, and both interreader and test-retest reliability for all readout parameters were reported by intraclass correlation coefficients (ICCs) and standard error of measurement (SEM). RESULTS: For the sciatic nerve, overall mean ± standard deviation MTR was 26.75 ± 3.5%, T2 was 64.54 ± 8.2 ms, and PSD was 340.93 ± 78.8. ICCs ranged between 0.81 (MTR) and 0.94 (PSD) for interreader reliability and between 0.75 (MTR) and 0.94 (PSD) for test-retest reliability. SEM for interreader reliability was 1.7% for MTR, 2.67 ms for T2, and 21.3 for PSD. SEM for test-retest reliability was 1.7% for MTR, 2.66 ms for T2, and 20.1 for PSD. CONCLUSIONS: MTI and T2 relaxometry of the sciatic nerve are reliable and reproducible. The values of measurement imprecision reported here may serve as a guide for correct interpretation of quantitative MRN biomarkers in future studies. KEY POINTS: • Magnetization transfer imaging (MTI) and T2 relaxometry of the sciatic nerve are reliable and reproducible. • The imprecision that is unavoidably associated with different scans or different readers can be estimated by the here presented SEM values for the biomarkers T2, PSD, and MTR. • These values may serve as a guide for correct interpretation of quantitative MRN biomarkers in future studies and possible clinical applications.

Total numbers and in-hospital mortality of patients with myocardial infarction in Germany during the FIFA soccer world cup 2014.

Environmental stress like important soccer events can induce excitation, stress and anger. We aimed to investigate (i) whether the FIFA soccer world cup (WC) 2014 and (ii) whether the soccer games of the German national team had an impact on total numbers and in-hospital mortality of patients with myocardial infarction (MI) in Germany. We analyzed data of MI inpatients of the German nationwide inpatient sample (2013-2015). Patients admitted due to MI during FIFA WC 2014 (12th June-13th July2014) were compared to those during the same period 2013 and 2015 (12th June-13th July). Total number of MI patients was higher during WC 2014 than in the comparison-period 2013 (18,479 vs.18,089, P < 0.001) and 2015 (18,479 vs.17,794, P < 0.001). WC was independently associated with higher MI numbers (2014 vs. 2013: OR 1.04 [95% CI 1.01-1.07]; 2014 vs. 2015: OR 1.07 [95% CI 1.04-1.10], P < 0.001). Patient characteristics and in-hospital mortality rate (8.3% vs. 8.3% vs. 8.4%) were similar during periods. In-hospital mortality rate was not affected by games of the German national team (8.9% vs. 8.1%, P = 0.110). However, we observed an increase regarding in-hospital mortality from 7.9 to 9.3% before to 12.0% at final-match-day. Number of hospital admissions due to MI in Germany was 3.7% higher during WC 2014 than during the same 31-day period 2015. While in-hospital mortality was not affected by the WC, the in-hospital mortality was highest at WC final.

Increased satellite cell apoptosis in vastus lateralis muscle after anterior cruciate ligament reconstruction.

OBJECTIVE: Recovery of the quadriceps femoris muscle after anterior ligament reconstruction is im-paired. The aim of this study was to investigate satellite cell content and function of the vastus lateralis muscle after anterior ligament reconstruction. METHODS: Biopsies were obtained from the vastus lateralis muscle of 16 recreational athletes immediately before and again 12 weeks after anterior ligament reconstruction. Total satellite cell number (Pax7+), activated (Pax7+/MyoD+), differentiating (Pax7-/MyoD+), and apoptotic (Pax7+/TUNEL+) satellite cells, myofibers expressing myosin heavy chain (MHC) I and II, and neonatal MHC (MHCneo) were determined immunohistochemically. RESULTS: After anterior ligament reconstruction, the number of apoptotic satellite cells was significantly (p = 0.019) increased, concomitant with a significant (p < 0.001) decrease in total satellite cell number, with no change in activated and differentiating satellite cell number. MHCneo+ myofibers tended towards an increase. CONCLUSION: Satellite cell apoptosis and the reduction in the satellite cell pool might provide an explanation for prolonged quadriceps muscle atrophy after anterior ligament reconstruction.

In Vivo Visualization of Tissue Damage Induced by Percutaneous Muscle Biopsy via Novel High-Resolution MR Imaging.

PURPOSE: Percutaneous muscle biopsy is the gold standard for tissue assessment in clinical practice and scientific studies. The aim of this study was to assess and quantify the ensuing tissue damage by in vivo magnetic resonance imaging (MRI). METHODS: In this prospective study, we enrolled 22 healthy participants who underwent MRI of the thigh musculature about 1 wk after a percutaneous muscle biopsy of the vastus lateralis muscle. A total of 17 participants also volunteered for a second MR examination 2 wk after biopsy. Volumes of susceptibility-weighted imaging (SWI) lesions and muscle edema were assessed by SWI and T2-weighted MRI, respectively, after manual segmentation by two independent readers. For quantitative in vivo hematoma volume assessment, we additionally determined signal changes induced by experimental hematoma in an ex vivo model. RESULTS: Mean overall volume of SWI lesions 1 wk after biopsy was 26.5 ± 21.7 µL, accompanied by a mean perifocal edema volume of 790.1 ± 591.4 µL. In participants who underwent two examinations, mean volume of SWI lesions slightly decreased from 29.8 ± 23.6 to 23.9 ± 16.8 µL within 1 wk (P = 0.13). Muscle edema volume decreased from 820.2 ± 632.4 to 359.6 ± 207.3 µL at the same time (P = 0.006). By calibration with the ex vivo findings, signal alterations on SWI corresponded to a blood volume of approximately 10-50 µL. CONCLUSIONS: Intramuscular hematoma and accompanying muscle edema after percutaneous biopsy are small and decrease rapidly within the first 2 wk. These in vivo findings underline the limited invasiveness of the procedure.

Influencing factors of cardiorespiratory fitness in allogeneic stem cell transplant candidates prior to transplantation.

PURPOSE: Cardiorespiratory fitness (CRF) seems to be prognostic prior to allogeneic stem cell transplantation (allo-HSCT). Influencing factors of CRF in allo-HSCT candidates have not been studied so far. Aim was to identify potentially influencing factors on CRF. METHODS: To assess CRF, a maximal cardiopulmonary exercise test (CPET) was performed on average 2.6 ± 7.2 days prior to admission. A regression analysis was conducted, with the following predictors: gender, age, body mass index (BMI), time between last therapy and allo-HSCT (t_Therapies), number of cardiotoxic therapies (n_Cardiotox), number of transplantations (n_Transplantations), comorbidity index (HCT-CI), hemoglobin level of the last 3 months (area under the curve), and physical activity. RESULTS: A total of 194 patients performed a CPET. VO2peak was significantly reduced compared with reference data. In total, VO2peak was 21.4 ml/min/kg (- 27.5%, p < 0.05). Men showed a significant larger percentage difference from reference value (- 29.1%, p < 0.05) than women (- 24.4%). VO2peak was significantly (p < 0.05) influenced by age (ß = - 0.11), female gender (ß = - 3.01), BMI (ß = - 0.44), n_Cardiotox (ß = - 0.73), hemoglobin level (ß = 0.56), and physical activity prior to diagnosis (ß = 0.10). CONCLUSIONS: Our study demonstrates a decreased CRF indicating the potential need of prehabilitative exercise. We revealed some influencing factors on CRF. Those patients could benefit the most from exercise.

Physical fitness and health-related quality of life in pediatric renal transplant recipients: An interventional trial with active video gaming.

BACKGROUND: Pediatric renal transplant recipients are at increased risk for cardiovascular diseases, one contributing factor is reduced cardiorespiratory fitness. The purpose was to evaluate cardiorespiratory fitness, motor coordination, muscle strength, daily physical activity, and health-related quality of life and to find out, if active video gaming is effective for improving these items in this patient population. METHODS: Twenty renal transplant recipients (13.5 ± 3.4 years) and 33 matched healthy controls (13.1 ± 3.2 years) performed a spiroergometry, a motor coordination test, and a maximal handgrip strength test. Quality of life was determined with a validated questionnaire, and daily physical activity was recorded with a physical activity monitor. Thirteen patients (12.9 ± 3.4 years) participated in a 6-week home-based exergaming intervention (3×/week for 30 minutes) and repeated all tests after that. RESULTS: The renal transplant recipients exhibited a substantial impairment compared with the controls in peak oxygen consumption (-31%, P < .001), motor competence (-44%, P < .001), daily physical activity (-33%, P = .001), and quality of life (-12%, P = .017). Handgrip strength was similar in both groups. Despite of low compliance in the intervention group, steps per hour were significantly increased after 6 weeks of exergaming (+31%, P = .043); however, all other measures remained unchanged. CONCLUSION: Cardiorespiratory fitness, motor competence, and quality of life are reduced in pediatric renal transplant recipients. Home-based exergaming is not appropriate to improve these items, probably due to a substantially impaired motor competence. However, it provided a stimulus for an increased daily physical activity.

Peripheral Nerve Diffusion Tensor Imaging : Interreader and Test-retest Reliability as Quantified by the Standard Error of Measurement.

PURPOSE: Diffusion tensor imaging (DTI) is increasingly being used in magnetic resonance neurography (MRN). The purpose of this study was to determine the interreader and test-retest reliability of peripheral nerve DTI in MRN with focus on the sciatic nerve. METHODS: In this prospective study 27 healthy volunteers each underwent 3 scans of a short DTI protocol on separate days consisting of a T2-weighted turbo spin-echo and single-shot DTI sequence of the sciatic nerve of the dominant leg. The DTI parameters fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were obtained after manual nerve segmentation by two independent readers. Intraclass correlation coefficients (ICC), standard error of measurement (SEM), and Bland-Altman plots were calculated as measures for both interreader and test-retest agreement for all readout parameters. RESULTS: The mean ± standard deviation was 0.507 ± 0.05 for FA, 1308.5 ± 162.4â€¯× 10-6 mm2/s for MD, 905.6 ± 145.4 ×10-6 mm2/s for RD and 2114.1 ± 219.2â€¯× 10-6 mm2/s for AD. The SEM for FA was 0.02 for interreader and test-retest agreement, the SEM for MD, RD, and AD ranged between 46.2â€¯× 10-6 mm2/s (RD) and 70.1â€¯× 10-6 mm2/s (AD) for interreader reliability and between 45.9â€¯× 10-6 mm2/s (RD) and 70.1â€¯× 10-6 mm2/s (AD) for test-retest reliability. The ICC for interreader reliability of DTI parameters ranged between 0.81 and 0.92 and ICC for test-retest reliability between 0.76 and 0.91. CONCLUSION: Peripheral nerve DTI of the sciatic nerve is reliable and reproducible. The measures presented here may serve as first orientation values of measurement accuracy when interpreting parameters of sciatic nerve DTI.

Strength Training Effects on Muscular Regeneration after ACL Reconstruction.

PURPOSE: Protracted quadriceps muscle atrophy is observed after anterior cruciate ligament reconstruction (ACL-R). The aim of this study was to assess if quadriceps strength training with eccentric overload (CON/ECC) is more efficient to induce muscle regeneration after ACL-R than conventional concentric/eccentric (CON/ECC) strength training. METHODS: Biopsies from the vastus lateralis muscle were obtained from 37 recreational athletes after 12 wk of regular rehabilitation after ACL-R and again after 12 wk with twice a week of either conventional CON/ECC (n = 16) or CON/ECC (n = 21) one-legged supervised leg-press training. Immunohistochemical analyses were used to determine satellite cell (SC) number (Pax7); activated SC number (Pax7/MyoD); fibers expressing myosin heavy-chain (MHC) I and II, MHC neonatal, and fiber cross-sectional area. Magnetic resonance imaging was performed to measure quadriceps cross-sectional area and isokinetic testing for the measurement of quadriceps strength. RESULTS: CON/ECC induced a significantly (P = 0.002) greater increase in quadriceps cross-sectional area than did CON/ECC. There also was a significant increase in the fiber cross-sectional areas of all fiber types and in quadriceps strength, but without significant difference between training groups. Only CON/ECC training led to a significant (P < 0.05) increase in percent type I fibers. After training, the number of MHC I/MHCneo fibers was significantly (P < 0.05) greater in the CON/ECC than after in the CON/ECC group. The proportion of hybrid fibers tended to decrease in both groups; percent type II fibers, SC number, and activated SC number remained unchanged. CONCLUSIONS: CON/ECC leads to significantly greater muscle hypertrophy compared with CON/ECC, but without the hypothesized enhancing effect on SC activation. At the same time, CON/ECC+ induces a less favorable slower muscle phenotype for strong and fast movements.