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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&#95;Therapies), number of cardiotoxic therapies (n&#95;Cardiotox), number of transplantations (n&#95;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. VO 2peak was significantly reduced compared with reference data. In total, VO 2peak 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%). VO 2peak was significantly (p < 0.05) influenced by age (β = - 0.11), female gender (β = - 3.01), BMI (β = - 0.44), n&#95;Cardiotox (β = - 0.73), hemoglobin level (β = 0.56), and physical activity prior to diagnosis (β = 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.

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 ± 162.4 × 10 -6  mm 2 /s for MD, 905.6 ± 145.4 ×10 -6  mm 2 /s for RD and 2114.1 ± 219.2 × 10 -6  mm 2 /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 46.2 × 10 -6  mm 2 /s (RD) and 70.1 × 10 -6  mm 2 /s (AD) for interreader reliability and between 45.9 × 10 -6  mm 2 /s (RD) and 70.1 × 10 -6  mm 2 /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.

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., (© 2019 The Authors. Pediatric Transplantation published by Wiley Periodicals, Inc.)

This document replaces the DGP recommendations published in 1998 and 2013. Based on recent studies and a consensus conference, the indications, choice and performance of the adequate exercise testing method and its necessary technical and staffing setting are discussed. Detailed recommendations are provided: for blood gas analysis and right heart catheterization during exercise, walk tests, spiroergometry, and stress echocardiography. The correct use of different exercise tests is discussed for specific situations in respiratory medicine: exercise induced asthma, obesity, monitoring of rehabilitation or therapeutical interventions, preoperative risk stratification, and evaluation in occupational medicine., Competing Interests: Die Autoren geben an, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

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.

Introduction: Professional boxing can lead to chronic traumatic encephalopathy, a variant of traumatic brain injury (TBI). Its occurrence in amateur boxers is a matter of debate since amateur boxing is considered to be less harmful due to more strict regulations. However, several studies using different methodological approaches have revealed subtle signs of TBI even in amateurs. Diffusion tensor imaging (DTI) is sensitive to microscopic white matter changes and has been proven useful in TBI when routine MR imaging often is unrevealing., Methods: DTI, with tract-based spatial statistics (TBSS) together with neuropsychological examination of executive functions and memory, was used to investigate a collective of 31 male amateur boxers and 31 age-matched controls as well as a subgroup of 19 individuals, respectively, who were additionally matched for intellectual performance (IQ)., Results: All participants had normal findings in neurological examination and conventional MR. Amateur boxers did not show deficits in neuropsychological tests when their IQ was taken into account. Fractional anisotropy was significantly reduced, while diffusivity measures were increased along central white matter tracts in the boxers group. These changes were in part associated with the number of fights., Conclusions: TBSS revealed widespread white matter disturbance partially related to the individual fighting history in amateur boxers. These findings closely resemble those in patients with accidental TBI and indicate similar histological changes in amateur boxers.

Dietary intake, vitamin status and oxidative stress were evaluated in 17 elite male boxers. Ten of them frequently reduced body weight rapidly before competitions (Weight Loss Group) and 7 did not practice rapid weight loss (Control Group). Food record checklists, blood samples for determination of vitamin status and plasma glutathione levels were obtained during a week of weight maintenance, a pre-competition week and a post-competition week. The average dietary intakes in both groups were 33 ± 8 kcal·kg(-1), 3.7 ± 1.1 g·kg(-1) carbohydrates, 1.5 ± 0.4 g·kg(-1) protein, 1.2 ± 0.4 g·kg(-1) fat and 2.2 ± 1.0 L water per day (excluding pre-competition week in Weight Loss Group). Energy (18 ± 7 kcal·kg(-1)), carbohydrate (2.2 ± 0.8 g·kg(-1)), protein (0.8 ± 0.4 g·kg(-1)), fat (0.6 ± 0.3 g·kg(-1)) and water (1.6 ± 0.6 L) consumption (P-values <0.001) and intakes of most vitamins (P-values < 0.05) were significantly reduced during the pre-competition week in the Weight Loss Group. In both groups, the intakes of vitamins A, E and folate were below recommended values throughout the three periods; however, blood vitamin and plasma glutathione levels did not change significantly. Our findings indicate a low-caloric and low-carbohydrate diet in elite boxers, regardless of participating in rapid weight loss or not. Apparently, the pre-competitional malnutitrition in the Weight Loss Group did not induce alterations in the vitamin and glutathione status.

The risk of sustaining injuries increases with fatigue. The aim of this study was to analyze the influence of fatigue on dynamic postural control in jump landing and stabilization (ST) in athletes of different levels. In all, 18 high-performance ball sports athletes and 24 recreationally active subjects performed a jump test (JT) before and at 1, 5, 10, 15, and 20 minutes after a 30-minute treadmill run at the individual anaerobic threshold. An overhead ball switch hit during a forward jump triggered indicator lamps on either side of a force plate. After landing on the plate, ST on 1 leg (no light cue) or a second jump sideways (toward a light cue) was required. The ST force integral index was calculated for the ST trials. Dynamic postural control was significantly impaired in jump landing and ST in the first minute after the run: mean difference ± SD: 0.25 ± 0.48 m·s-1 (95% confidence interval: 0.10-0.40 m·s-1, p = 0.043; analysis of variance). No significant group differences were found. Under fatigued conditions, dynamic postural control in jump landing was impaired in an unexpected ST task. Not only recreational but also high-performance athletes were affected. Ball sports athletes could add a training exercise to their workout, which alternates between periods of high effort and neuromuscular training. Resistance to fatigue effects should be checked on a regular basis using JTs.

Objective: To characterise the time course of changes in haemoglobin mass (Hbmass) in response to altitude exposure., Methods: This meta-analysis uses raw data from 17 studies that used carbon monoxide rebreathing to determine Hbmass prealtitude, during altitude and postaltitude. Seven studies were classic altitude training, eight were live high train low (LHTL) and two mixed classic and LHTL. Separate linear-mixed models were fitted to the data from the 17 studies and the resultant estimates of the effects of altitude used in a random effects meta-analysis to obtain an overall estimate of the effect of altitude, with separate analyses during altitude and postaltitude. In addition, within-subject differences from the prealtitude phase for altitude participant and all the data on control participants were used to estimate the analytical SD. The 'true' between-subject response to altitude was estimated from the within-subject differences on altitude participants, between the prealtitude and during-altitude phases, together with the estimated analytical SD., Results: During-altitude Hbmass was estimated to increase by ∼1.1%/100 h for LHTL and classic altitude. Postaltitude Hbmass was estimated to be 3.3% higher than prealtitude values for up to 20 days. The within-subject SD was constant at ∼2% for up to 7 days between observations, indicative of analytical error. A 95% prediction interval for the 'true' response of an athlete exposed to 300 h of altitude was estimated to be 1.1-6%., Conclusions: Camps as short as 2 weeks of classic and LHTL altitude will quite likely increase Hbmass and most athletes can expect benefit.

Context: Dehydration is assumed to be a major adverse effect associated with rapid loss of body mass for competing in a lower weight class in combat sports. However, the effects of such weight cutting on body fluid balance in a real-life setting are unknown., Objective: To examine the effects of 5% or greater loss of body mass within a few days before competition on body water, blood volume, and plasma volume in elite amateur boxers., Design: Case-control study., Setting: Sports medicine laboratory., Patients or Other Participants: Seventeen male boxers (age = 19.2 ± 2.9 years, height = 175.1 ± 7.0 cm, mass = 65.6 ± 9.2 kg) were assigned to the weight-loss group (WLG; n = 10) or the control group (CON; n = 7)., Intervention(s): The WLG reduced body mass by restricting fluid and food and inducing excessive sweat loss by adhering to individual methods. The CON participated in their usual precompetition training., Main Outcome Measure(s): During an ordinary training period (t-1), 2 days before competition (t-2), and 1 week after competition (t-3), we performed bioelectrical impedance measurements; calculated total body water, intracellular water, and extracellular water; and estimated total hemoglobin mass (tHbmass), blood volume, and plasma volume by the CO-rebreathing method., Results: In the WLG, the loss of body mass (5.6% ± 1.7%) led to decreases in total body water (6.0% ± 0.9%), extracellular water (12.4% ± 7.6%), tHbmass (5.3% ± 3.8%), blood volume (7.6% ± 2.1%; P < .001), and plasma volume (8.6% ± 3.9%). The intracellular water did not change (P > .05). At t-3, total body water, extracellular water, and plasma volume had returned to near baseline values, but tHbmass and blood volume still were less than baseline values (P < .05). In CON, we found no changes (P > .05)., Conclusions: In a real-life setting, the loss of approximately 6% body mass within 5 days induced hypohydration, which became evident by the decreases in body water and plasma volume. The reduction in tHbmass was a surprising observation that needs further investigation.

This document replaces the DGP recommendations published in 1998. Based on recent studies and a consensus conference, the indications, choice and performance of the adequate exercise testing method in its necessary technical and staffing setting are discussed. Detailed recommendations are provided: for arterial blood gas analysis and right heart catherterization during exercise, 6-minute walk test, spiroergometry, and stress echocardiography. The correct use of different exercise tests is discussed for specific situations in respiratory medicine: exercise induced asthma, monitoring of physical training or therapeutical interventions, preoperative risk stratification, and evaluation in occupational medicine., (© Georg Thieme Verlag KG Stuttgart · New York.)

Objectives: To test the reliability of heart rate (HR) recommendations for cardiac rehabilitation training obtained from different treadmill tests., Background: For training in cardiac rehabilitation, HR recommendations are derived from cardio-pulmonary tests. Exercise intensity is often controlled through self-monitoring HR by the cardiac patients., Design: Non-randomized clinical trial., Methods: 25 patients of a cardiac sports group (six women, 19 men, age 68.3 ± 5 years, height 171 ± 10 cm, weight 82 ± 12.8 kg) performed a stepwise increasing treadmill test according to a modified Stanford protocol (S) and a ramp treadmill test according to the Balke-Ware protocol (B) until volitional exhaustion. In 16 patients, HR was assessed with a HR monitor and compared with HR obtained by self-monitoring through pulse palpation during three training sessions., Results: Similar peak cardiopulmonary responses were obtained with the two exercise protocols of significantly (p < 0.001) different duration (S 22:05 ± 7:11 min, B 13:31 ± 4:20 min). During the training sessions, HR exceeded the upper HR limit set at 85% HR(peak) in 15 patients and in nine patients, higher HR(peak) than in the exercise tests was observed. Five participants did not accurately measure their HR by pulse palpation., Conclusions: All but one patient of the cardiac sports group did not adhere to the HR recommendations derived from incremental treadmill testing, most likely because volitional exhaustion occurred in both treadmill tests before maximal cardiopulmonary responses were reached. In about 30% of the patients, training intensity could not be controlled by self-monitoring because of inaccurate pulse palpation.

Repeated biopsy sampling from one muscle is necessary to investigate muscular adaptation to different forms of exercise as adaptation is thought to be the result of cumulative effects of transient changes in gene expression in response to single exercise bouts. In a crossover study, we obtained four fine needle biopsies from one vastus lateralis muscle of 11 male subjects (25.9 ± 3.8 yr, 179.2 ± 4.8 cm, 76.5 ± 7.0 kg), taken before (baseline), 1, 4, and 24 h after one bout of squatting exercise performed as conventional squatting or as whole body vibration exercise. To investigate if the repeated biopsy sampling has a confounding effect on the observed changes in gene expression, four fine needle biopsies from one vastus lateralis muscle were also taken from 8 male nonexercising control subjects (24.5 ± 3.7 yr, 180.6 ± 1.2 cm, 81.2 ± 1.6 kg) at the equivalent time points. Using RT-PCR, we observed similar patterns of change in the squatting as well as in the control group for the mRNAs of interleukin 6 (IL-6), IL-6 receptor, insulin-like growth factor 1, p21, phosphofructokinase, and glucose transporter in relation to the baseline biopsy. In conclusion, multiple fine needle biopsies obtained from the same muscle region can per se influence the expression of marker genes induced by an acute bout of resistance exercise.

To evaluate differences in total haemoglobin mass (tHb mass) and in red blood cell profile between elite endurance-trained (END) and non-endurance-trained (nEND) male and female adolescent athletes, tHb mass (CO rebreathing) and specific variables of red blood cell profile (haemoglobin concentration, haematocrit, erythrocyte indices) were determined in 59 elite junior athletes (29 END, 30 nEND). We hypothesized that at the age of 15-17 years, regular endurance training might induce a significant increase in tHb mass and changes in red blood cell profile. Therefore, all parameters were again determined after 6, 12 and 18 months in a subset of 27 subjects (17 END, 10 nEND). In END, tHb mass related to body weight was ~15% greater than in nEND (11.2 ± 1.6  vs. 9.7 ± 1.3 g kg(-1), P < 0.001), whereas no significant differences were observed for the red blood cell profile. In both groups, tHb mass related to body weight and the variables of red blood cell profile had not changed significantly after 6, 12 and 18 months of regular training. In conclusion, in elite junior athletes, differences in tHb mass between END and nEND were similar, however, smaller compared with previously in adult athletes reported values. At the age of 15-17 years, 18 months of regular training did not induce significant changes in tHb mass beyond alterations explained by physical growth and also variables of red blood cell profile did not change significantly.

The purpose of the study was to test the hypothesis that myofiber recruitment is enhanced when whole-body vibration (WBV) is added to squat training. In a randomized cross-over design, 14 recreationally active men were subjected to 2 sessions consisting of 5 sets of 10 squats with external load, performed either on a vibration platform (whole-body vibration squatting [WBVS]) or conventionally without WBV (CON). Electromyographic (EMG) activity of the right vastus lateralis muscle was continuously recorded during WBVS and CON. The integrated EMG values were normalized to the EMG activity recorded during measurement of the maximal voluntary contraction force (MVC) on an isometric leg press at the beginning of each training session. Capillary lactate concentration was determined before and repeatedly after the squatting exercise. Overall mean normalized and integrated EMG (nIEMG) activity during WBVS (62 ± 4% MVC) was significantly (p < 0.001) higher compared with CON (47 ± 2% MVC). There was a tendency for nIEMG to increase during the 5 sets of 10 squats performed as WBVS (p = 0.089), whereas there was a significant (p < 0.001) decrease in nIEMG during CON. Whole-body vibration squatting induced a significantly (p < 0.001) larger increase in capillary lactate than CON (3.03 ± 0.32 vs. 1.60 ± 0.30 mmol · L(-1), p < 0.001). The increased myoelectric activity and the enhanced exercise-induced increase in capillary lactate concentration during WBVS provide evidence for augmented recruitment of muscle tissue when WBV is added to exhaustive squatting exercise.

In classic concentric/eccentric exercise, the same absolute load is applied in concentric and eccentric actions, which infers a smaller relative eccentric load. We compared the effects of 6 weeks of classic concentric/eccentric quadriceps strength training (CON/ECC, 11 subjects) to eccentric overload training (CON/ECC+, 14 subjects) in athletes accustomed to regular strength training. The parameters determined included functional tests, quadriceps and fibre cross-sectional area (CSA), fibre type distribution by ATPase staining, localisation of myosin heavy chain (MHC) isoform mRNAs by situ hybridization and the steady-state levels of 48 marker mRNAs (RT-PCR) in vastus lateralis biopsies taken before and after training. Both training forms had anabolic effects with significant increases in quadriceps CSA, maximal strength, ribosomal RNA content and the levels of mRNAs involved in growth and regeneration. Only the CON/ECC+ training led to significantly increased height in a squat jump test. This was accompanied by significant increases in IIX fibre CSA, in the percentage of type IIA fibres expressing MHC IIx mRNA, in the level of mRNAs preferentially expressed in fast, glycolytic fibres, and in post-exercise capillary lactate. The enhanced eccentric load apparently led to a subtly faster gene expression pattern and induced a shift towards a faster muscle phenotype plus associated adaptations that make a muscle better suited for fast, explosive movements.