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Background The World Health Organization–approved Xpert MTB/XDR test detects Mycobacterium tuberculosis and resistance to isoniazid, fluoroquinolones, ethionamide, and injectable drugs directly in specimens. This pragmatic, laboratory-based study assessed the diagnostic accuracy and feasibility of a reflex testing approach, where Xpert MTB/XDR was performed on residual specimens previously processed for Xpert MTB/RIF Ultra. Methods Routine respiratory specimens, processed for Xpert MTB/RIF Ultra, were stored in sample reagent buffer at 2°C–8°C. If rifampicin resistant, the residual specimen was assessed for adequate volume (≥2 mL) and tested with Xpert MTB/XDR, with storage time recorded. A second specimen was used for routine and reference standard testing (culture and sequencing). Results Specimens (99% sputum) from 763 participants submitted to 2 large routine laboratories were included. Xpert MTB/XDR yielded valid resistance detection results in 639 (84%), compared with 507 (66%) for routine testing (difference [95% CI], 18% [13%–22%]). The median turnaround time for results was 23 hours for Xpert MTB/XDR and 15 days for routine testing. While 748 specimens (98%) were ≥2 mL, only 102 (13%) were stored for ≤4 hours. By the reference standard, 284 of 394 (72%) were isoniazid resistant, and 57 of 380 (15%) were fluroquinolone resistant. The sensitivities of Xpert MTB/XDR were 94% (95% CI, 91%–97%) for isoniazid and 91% (81%–97%) for fluoroquinolone resistance detection. The specificities were 98% (94%–100%) and 100% (98%–100%), respectively. Conclusions Xpert MTB/XDR performed favorably compared with the reference, and the reflex testing approach increased results availability over routine testing, while dramatically decreasing turnaround time from weeks to hours. Laboratory workflow precluded testing within the manufacturer-recommended 4-hour storage time, but longer storage did not appear detrimental. [ABSTRACT FROM AUTHOR]

Background. Osteoarticular infections (OAI) are very common in children living in low- and middle-income countries, yet the bacterial aetiology and antibiotic susceptibility of OAI in children are not well described. Objective. To determine bacterial aetiology and antibiotic susceptibility of OAI in paediatric patients in a regional hospital in Cape Town, South Africa. Methods. The study included all patients who underwent surgery for OAI over a 3-year period, and those with organisms identified from tissue, pus, fluid or blood. Duplicate cultures from the same patient were excluded if the organism and antibiotic susceptibility profiles were the same. Patients were categorised by age and class of infection (septic arthritis, acute osteomyelitis, fracture-related infection, postoperative sepsis and chronic osteomyelitis) and organisms were stratified accordingly. Results. We identified 132 organisms from 123 samples collected from 96 patients. Most cultured organisms were from children older than 3 years with acute haematogenous septic arthritis, osteomyelitis or both. Methicillin-sensitive Staphylococcus aureus (S. aureus) accounted for 56% (n=74/132) of organisms cultured. The Enterobacterales accounted for 17% (n=22/132) of organisms cultured, mostly in the fracture-related and postoperative infection groups. Of these, six each were extended-spectrum β-lactamase producers and AmpC producers, respectively. There were no carbapenemase-producing Enterobacterales. Conclusion. Methicillin-sensitive S. aureus is the most common infecting organism in paediatric OAI and anti-staphylococcal penicillin is the most appropriate empiric treatment for haematogenous OAI in our environment. In fracture-related or postoperative infections, Enterobacterales were more frequently cultured, and treatment should be guided by culture and susceptibility results. [ABSTRACT FROM AUTHOR]

Khelan R Dheda,1 Chad M Centner,2 Lindsay Wilson,3,4 Anil Pooran,3,4 Shireen Grimwood,2 Yonas T Ghebrekristos,2 Suzette Oelofse,3,4 Ivan A Joubert,5 Aliasgar Esmail,3,4 Michele Tomasicchio3,4 1Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa; 2Division of Medical Microbiology, National Health Laboratory Services (NHLS)/Groote Schuur Hospital, Microbiology, University of Cape Town, Cape Town, South Africa; 3Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town and UCT Lung Institute, Cape Town, South Africa; 4South African MRC/UCT Centre for the Study of Antimicrobial Resistance, University of Cape Town, Cape Town, South Africa; 5Division of Critical Care, Department of Anaesthesia and Perioperative Medicine, University of Cape Town, Cape Town, South AfricaCorrespondence: Michele Tomasicchio, Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town and UCT Lung Institute, Cape Town, South Africa, Tel +27 21 650 4331, Fax +27 21 650 3824, Email michele.tomasicchio@uct.ac.zaPurpose: Carbapenem-resistant bacteria (CRB) pose a major health risk to patients in intensive care units (ICU) across African hospitals. There are hardly any data about the role of hospital sinks as reservoirs of CRB in resource-poor African settings. Furthermore, the specific within-sink location of the highest concentration of pathogens and the role of splash back as a transmission mechanism remains poorly clarified.Methods: We swabbed ICU sluice room sinks in a tertiary hospital in Cape Town, South Africa. Swabs were taken from four different parts of the sluice room sinks (tap-opening, trap, below the trap, and u-bend). Dilutions were prepared and plated on carbapenem-infused agar. Colonies were identified and drug resistance profiles were determined using a biochemical analyser. To evaluate the potential transmission from the sink, similar plates were placed at fixed distances from the sink when the tap was turned on and off.Results: CRB were isolated from the trap, water interface below the trap, and the u-bend (the latter harboured the highest density of CRB species). Five CRB, resistant to at least 7 antibiotic classes, were isolated including Pseudomonas, Klebsiella, Citrobacter, Serratia, and Providencia. CRB could be cultured from droplets that fell on agar-containing plates placed at a varying distance from the trap.Conclusion: There is a higher density of CRB in the u-bend of ICU sluice room sinks which can act as a potential source of transmission. The data inform targeted CRB transmission-interruption strategies in resource-poor settings.Keywords: carbapenem-resistant bacteria, multi drug resistant bacteria, sluice room sink, intensive care units, antimicrobial resistance

Physical exercise induces acute psychophysiological responses leading to chronic adaptations when the exercise stimulus is applied repeatedly, at sufficient time periods, and with appropriate magnitude. To maximize long-term training adaptations, it is crucial to control and manipulate the external load and the resulting psychophysiological strain. Therefore, scientists have developed a theoretical framework that distinguishes between the physical work performed during exercise (i.e., external load/intensity) and indicators of the body's psychophysiological response (i.e., internal load/intensity). However, the application of blood flow restriction (BFR) during exercise with low external loads/intensities (e.g., ≤ 30% of the one-repetition-maximum, ≤ 50% of maximum oxygen uptake) can induce physiological and perceptual responses, which are commonly associated with high external loads/intensities. This current opinion aimed to emphasize the mismatch between external and internal load/intensity when BFR is applied during exercise. In this regard, there is evidence that BFR can be used to manipulate both external load/intensity (by reducing total work when exercise is performed to exhaustion) and internal load/intensity (by leading to higher physiological and perceptual responses compared to exercise performed with the same external load/intensity without BFR). Furthermore, it is proposed to consider BFR as an additional exercise determinant, given that the amount of BFR pressure can determine not only the internal but also external load/intensity. Finally, terminological recommendations for the use of the proposed terms in the scientific context and for practitioners are given, which should be considered when designing, reporting, discussing, and presenting BFR studies, exercise, and/or training programs., (© 2024. The Author(s).)

Background: Applying whole-body electromyostimulation (wbEMS) to voluntary activation of the muscle is known to impact motor unit recruitment. Thus, wbEMS as an additional training stimulus enhances force-related capacities. This study aimed to evaluate the mono- and multiarticular strength adaptations to a running intervention with wbEMS compared to running without wbEMS., Methods: In a randomized controlled trial (RCT), 59 healthy participants (32 female/ 27 male, 41 ± 7 years) with minor running experience conducted an eight-week running intervention (2x/ week à 20 min) with a wbEMS suit (EG) or without wbEMS (control group, CG). Maximal isokinetic knee extensor and flexor strength and jump height during countermovement jumps were recorded prior and after the intervention to assess maximal strength and power., Results: Following eight weeks of running, maximal isokinetic knee extension torque decreased significantly over time for both interventions (EG Δ -4%, CG Δ -4%; F(1, 44.14) = 5.96, p = 0.02, η = 0.12). No changes were observed for flexion torque (F(1, 43.20) = 3.93, p = 0.05, η = 0.08) or jump height (F(1, 43.04) = 0.32, p = 0.57, η  = 0.01)., Conclusions: The outcomes indicate that there is no additional effect over neuromuscular function adaptations with the inclusion of wbEMS during running training. Knee extensor strength is even slightly reduced which supports the principle of training specificity in regards to strength adaptation. We conclude that strength improvements cannot be achieved by running with wbEMS., Trial Registration: German Clinical Trials Register, ID DRKS00026827, date 10/26/21., (© 2024. The Author(s).)

Background: Studies showed changes in the central nervous system in patients who sustained an anterior cruciate ligament tear. There is a lack of evidence regarding the effectiveness of transcranial direct-current stimulation in such patients., Methods: A sham-controlled randomised study. One group of patients (n = 6) underwent 6 weeks of sensorimotor training after an anterior cruciate ligament tear during transcranial direct-current stimulation. The stimulation consisted of 20 minutes (3 sessions/week; 2 weeks) of 2 mA anodal transcranial direct-current stimulation over the primary motor and premotor cortex. The second group (n = 6) received sham stimulation with 6 weeks of sensorimotor training. Centre of pressure deviations in the medio-lateral and anterior-posterior direction and centre of pressure velocity were measured., Results: The results demonstrated a significant effect of sensorimotor training on the centre of pressure in medio-lateral and anterior-posterior direction (p=0.025) (p=0.03) in the leg in which an anterior cruciate ligament tear occurred. The type of training did not affect the results. Post-hoc tests showed no significant effect of training in the subgroups (p≥0.115)., Conclusion: Sensorimotor training led to a decrease in sway of the centre of pressure in patients who sustained an anterior cruciate ligament tear, but the addition of anodal transcranial direct-current stimulation placed over the primary motor cortex did not potentiate the adaptive responses of the sensorimotor training., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Background: HIV-associated tuberculosis (TB) contributes disproportionately to global tuberculosis mortality. Patients hospitalised at the time of the diagnosis of HIV-associated disseminated TB are typically severely ill and have a high mortality risk despite initiation of tuberculosis treatment. The objective of the study is to assess the safety and efficacy of both intensified TB treatment (high dose rifampicin plus levofloxacin) and immunomodulation with corticosteroids as interventions to reduce early mortality in hospitalised patients with HIV-associated disseminated TB., Methods: This is a phase III randomised controlled superiority trial, evaluating two interventions in a 2 × 2 factorial design: (1) high dose rifampicin (35 mg/kg/day) plus levofloxacin added to standard TB treatment for the first 14 days versus standard tuberculosis treatment and (2) adjunctive corticosteroids (prednisone 1.5 mg/kg/day) versus identical placebo for the first 14 days of TB treatment. The study population is HIV-positive patients diagnosed with disseminated TB (defined as being positive by at least one of the following assays: urine Alere LAM, urine Xpert MTB/RIF Ultra or blood Xpert MTB/RIF Ultra) during a hospital admission. The primary endpoint is all-cause mortality at 12 weeks comparing, first, patients receiving intensified TB treatment to standard of care and, second, patients receiving corticosteroids to those receiving placebo. Analysis of the primary endpoint will be by intention to treat. Secondary endpoints include all-cause mortality at 2 and 24 weeks. Safety and tolerability endpoints include hepatoxicity evaluations and corticosteroid-related adverse events., Discussion: Disseminated TB is characterised by a high mycobacterial load and patients are often critically ill at presentation, with features of sepsis, which carries a high mortality risk. Interventions that reduce this high mycobacterial load or modulate associated immune activation could potentially reduce mortality. If found to be safe and effective, the interventions being evaluated in this trial could be easily implemented in clinical practice., Trial Registration: ClinicalTrials.gov NCT04951986. Registered on 7 July 2021 https://clinicaltrials.gov/study/NCT04951986., (© 2024. The Author(s).)

Purpose: Previous evidence indicated that the tibiofemoral bone configuration might elevate the risk of an anterior cruciate ligament (ACL) injury. Furthermore, a low hamstring-to-quadriceps muscle ratio predisposes especially females to unfavourable knee kinematics. The primary objective of the present study was to investigate sex-specific associations between tibiofemoral bone geometry and isokinetic knee flexion torque in patients with primary ACL injury followed by ACL reconstruction., Methods: N = 100 patients (72 = male, 28 = female, age = 31.3 ± 10.2, body mass index = 25.3 ± 3.6) with primary ACL rupture with isokinetic knee flexion torque assessments before and 6 months after ACL reconstruction surgery were analysed. Magnetic resonance imaging scans were analysed for medial posterior tibial slope (MPTS) and lateral posterior tibial slope, notch width index (NWI) and lateral femoral condyle index (LFCI). Additionally, isokinetic knee flexion torque (60°/s) and hamstring-quadriceps ratios were evaluated. Subsequently, functional parameters were correlated with imaging data for gender subgroups., Results: The findings showed that presurgical isokinetic knee flexion torque was not associated with any marker of femoral or tibial bone geometry. Further, while significant differences were observed between female (0.883 ± 0.31 Nm/kg) and male (1.18 ± 0.35 Nm/kg) patients regarding preoperative normalized knee flexion torque (p < 0.001), no significant sex differences were found for percentage increases in normalized knee flexion torque from presurgery to postsurgery. Generally, female patients demonstrated significantly higher MPTS magnitudes (p < 0.05) and lower LFCI values (p < 0.05) compared to men., Conclusion: The present results demonstrated no association between tibial or femoral bone geometry and muscle strength of the hamstrings in patients with ACL reconstruction, indicating an important mismatch of muscular compensation to deviations in bone geometry. There were no sex-specific differences in tibiofemoral bone parameters., Level of Evidence: Level III., (© 2024 European Society of Sports Traumatology, Knee Surgery and Arthroscopy.)

Background: Rotator cuff tears are a common musculoskeletal condition which can lead to functional limitations and impairments in quality of life. The purpose of the present study was to investigate the effects of arthroscopic repair surgery on isokinetic muscle function before and 6-months after surgery. Additionally, the mediating effects of tear type, tear size and tendon retraction were examined., Methods: Data from n = 67 patients (56 ± 9 years) with full-thickness rotator cuff tears were analyzed. Before and 6-months after surgery, isokinetic muscle function in external/internal rotation and abduction/adduction movements was assessed. Further, tear size, tear type (Collin classification) and tendon retraction (Patte classification) were analyzed using magnetic resonance imaging., Results: After statistical analysis, a significant increase in limb symmetry index of external (P < .001), internal rotation (P < .01), abduction (P < .001), and adduction (P < .001) were observed from preto postsurgery. The results revealed that tear size and tendon tear type significantly mediated the functional outcome, with no significant effect of tendon retraction., Conclusion: The present findings point toward the notion that the functional outcome following rotator cuff repair was significantly dependent on tear type and tear size but not tendon retraction. Patients with larger sized tears presented pronounced deficits following 6-months indicating that rehabilitation times need to be adjusted accordingly., (Copyright © 2024 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Applying blood flow restriction (BFR) during low-load exercise induces beneficial adaptations of the myotendinous and neuromuscular systems. Despite the low mechanical tension, BFR exercise facilitates a localized hypoxic environment and increase in metabolic stress, widely regarded as the primary stimulus for tissue adaptations. First evidence indicates that low-load BFR exercise is effective in promoting an osteogenic response in bone, although this has previously been postulated to adapt primarily during high-impact weight-bearing exercise. Besides studies investigating the acute response of bone biomarkers following BFR exercise, first long-term trials demonstrate beneficial adaptations in bone in both healthy and clinical populations. Despite the increasing number of studies, the physiological mechanisms are largely unknown. Moreover, heterogeneity in methodological approaches such as biomarkers of bone metabolism measured, participant and study characteristics, and time course of measurement renders it difficult to formulate accurate conclusions. Furthermore, incongruity in the methods of BFR application (e.g., cuff pressure) limits the comparability of datasets and thus hinders generalizability of study findings. Appropriate use of biomarkers, effective BFR application, and befitting study design have the potential to progress knowledge on the acute and chronic response of bone to BFR exercise and contribute toward the development of a novel strategy to protect or enhance bone health. Therefore, the purpose of the present synthesis review is to 1 ) evaluate current mechanistic evidence; 2 ) discuss and offer explanations for similar and contrasting data findings; and 3 ) create a methodological framework for future mechanistic and applied research.

Objective: Syphilis and HIV coinfection is highly prevalent in South Africa, and both can cause neurological complications. We describe the clinical presentation and outcome of neurosyphilis in patients with and without HIV coinfection diagnosed at a tertiary facility, Groote Schuur Hospital (GSH), in South Africa., Methods: We retrospectively analyzed folders of adults with positive cerebrospinal fluid (CSF) fluorescent treponemal antibody absorption test in 2018 and 2019, with follow-up data collected until 2022., Results: HIV-coinfection was identified in 35% of the 69 included patients. Patients with HIV-coinfection were more likely to be female (58% vs 25% female, p < 0.01), and present earlier (median age = 31 years vs. 40 years, p < 0.001). Neuropsychiatric manifestations (confusion, dementia, psychosis), and strokes were the commonest clinical presentations in both groups. Those with HIV-coinfection were significantly less likely to be diagnosed with neurosyphilis by the treating clinician (71% vs. 91%, p < 0.05), as were those with a negative CSF Venereal Disease Research Laboratory (74% vs. 94%, p < 0.05). Accurate diagnosis of neurosyphilis was associated with an increased 12-month survival (alive: N = 36 [63%]) relative to those who did not receive an accurate diagnosis (alive: N = 2 [17%], p < 0.05). Those who were optimally treated with antibiotics had significantly higher 12-month survival (alive: N = 33, 63%) compared to those with suboptimal treatment (alive: N = 5, 29%), p < 0.01., Conclusion: Neurosyphilis presented similarly in those with and without HIV-coinfection. Accurate identification and optimal antibiotic treatment of neurosyphilis, particularly in CSF VDRL negative patients and those with HIV-coinfection, is necessary to improve patient survival., Competing Interests: Declaration of Competing Interest No conflicts of interest., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

ABSTRACT The purpose of this study was to investigate the effect of a supplementation with specific collagen peptides (SCP) combined with resistance training (RT) on changes in structural properties of the patellar tendon. Furthermore, tendon stiffness as well as maximal voluntary knee extension strength and cross-sectional area (CSA) of the rectus femoris muscle were assessed. In a randomized, placebo-controlled study, 50 healthy, moderately active male participants completed a 14-week resistance training program with three weekly sessions (70-85% of 1 repetition maximum [1RM]) for the knee extensors. While the SCP group received 5g of specific collagen peptides daily, the other group received the same amount of a placebo (PLA) supplement. The SCP supplementation led to a significant greater ( p  < 0.05) increase in patellar tendon CSA compared with the PLA group at 60% and 70% of the patellar tendon length starting from the proximal insertion. Both groups increased tendon stiffness ( p  < 0.01), muscle CSA ( p  < 0.05) and muscular strength ( p  < 0.001) throughout the intervention without significant differences between the groups. The current study shows that in healthy, moderately active men, supplementation of SCP in combination with RT leads to greater increase in patellar tendon CSA than RT alone. Since underlying mechanisms of tendon hypertrophy are currently unknown, further studies should investigate potential mechanisms causing the increased morphology adaptions following SCP supplementation. Trial registration: German Clinical Trials Register identifier: DRKS00029244..

Background: First evidence indicates that the supplementation of specific collagen peptides (SCP) is associated with a significant improvement in running performance in physically active women; however, it is unclear if the same is true in males. The purpose of the present study was to investigate the effects of a concurrent training program including 60 min of continuous moderate intensity running training and 15 min of dynamic resistance training combined with supplementation of SCP on parameters of running performance in moderately trained males., Methods: In a double-blind, placebo-controlled, randomized trial, participants performed a 12 weeks concurrent training and ingested 15 g of SCP [treatment group (TG)] or placebo [control group (CG)] daily. Before and after the intervention, running endurance performance was measured by a 1-h time trial on a running track. Velocity at the lactate threshold (V LT ) and at the individual anaerobic threshold (V IAT ) were assessed on a treadmill ergometer. Body composition was evaluated by bioelectrical impedance analysis., Results: Thirty-two men (28.4 ± 5.2 years) completed the study and were included in the analysis. After 12 weeks, TG had a statistically significant (p ≤ 0.05) higher increase in running distance (1727 ± 705 m) compared to the CG (1018 ± 976 m) in the time trial. V LT increased in the TG by 0.680 ± 1.27 km h -1 and slightly decreased by - 0.135 ± 0.978 km h -1 in the CG, resulting in statistically significant group differences (p ≤ 0.05). A significantly higher improvement in V IAT (p ≤ 0.05) was shown in the TG compared with the CG only (1.660 ± 1.022 km h -1 vs 0.606 ± 0.974 km h -1 ; p ≤ 0.01). Fat mass decreased (TG - 1.7 ± 1.6 kg; CG - 1.2 ± 2.0 kg) and fat free mass increased (TG 0.2 ± 1.2 kg; CG 0.5 ± 1.3 kg) in both groups with no significant group differences., Conclusion: In summary, supplementation with 15 g of SCP improved running performance in a 1-h time trial and enhanced indicators of endurance capacity at submaximal exercise intensities such as an increased velocity at the lactate as well as the anaerobic threshold more effectively than CT alone., Trial Registration: ETK: 123/17; DRKS-ID: DRKS00015529 (Registered 07 November 2018-Retrospectively registered); https://drks.de/search/de/trial/DRKS00015529., (© 2023. The Author(s).)

Web-based lifestyle interventions are a new area of health research. This randomized controlled trial evaluated the effectiveness of an interactive web-based health program on physical fitness and health. N = 189 healthy adults participated in a 12-week interactive (intervention) or non-interactive (control) web-based health program. The intervention provided a web-based lifestyle intervention to promote physical activity and fitness through individualized activities as part of a fully automated, multimodal health program. The control intervention included health information. Cardiorespiratory fitness measured as maximum oxygen uptake (VO 2 max) was the primary outcome, while musculoskeletal fitness, physical activity and dietary behavior, and physiological health outcomes were assessed as secondary outcomes (t0: 0 months, t1: 3 months, t2: 9 months, t3: 15 months). Statistical analysis was performed with robust linear mixed models. There were significant time effects in the primary outcome (VO 2 max) (t0-t1: p = 0.018) and individual secondary outcomes for the interactive web-based health program, but no significant interaction effects in any of the outcomes between the interactive and non-interactive web-based health program. This study did not demonstrate the effectiveness of an interactive compared with a non-interactive web-based health program in physically inactive adults. Future research should further develop the evidence on web-based lifestyle interventions.

Background: This study aimed to evaluate the physiological and metabolic adaptations to an eight-week running intervention with whole-body electromyostimulation (wbEMS) compared to running without wbEMS., Methods: In a randomized controlled trial (RCT), 59 healthy participants (32 female/ 27 male, 41 ± 7 years, rel.V̇O 2max 40.2 ± 7.4 ml/min/kg) ran twice weekly à 20 min for eight weeks either with a wbEMS suit (EG) or without wbEMS (control group, CG). Before and after the intervention, (i) rel.V̇O 2max , heart rate and time to exhaustion were recorded with an incremental step test with an incremental rate of 1.20 km/h every 3 min. They were interpreted at aerobic and (indirect) anaerobic lactate thresholds as well as at maximum performance. (ii) Resting metabolic rate (RQ) as well as (iii) body composition (%fat) were assessed., Results: Following the intervention, V̇O 2max was significantly enhanced for both groups (EG ∆13 ± 3%, CG ∆9 ± 3%). Velocity was elevated at lactate thresholds and maximum running speed (EG ∆3 ± 1%, CG ∆2 ± 1%); HR max was slightly reduced by -1 beat/min. No significant changes were observed for time until exhaustion and lactate. RQ was significantly enhanced following both trainings by + 7%. %fat was reduced for both groups (EG ∆-11 ± 3%, CG ∆-16 ± 5%), without any changes in body mass. Results did not differ significantly between groups., Conclusions: Both interventions had a positive impact on aerobic power. The rightward shift of the time-velocity graph points towards improved endurance performance. The effects of wbEMS are comparable to those after high-intensity training and might offer a time-efficient alternative to affect physiological and metabolic effects., Trial Registration: German Clinical Trials Register, ID DRKS00026827, date 10/26/21., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Abstract: Keller, M, Faude, O, Gollhofer, A, and Centner, C. Can we make blood flow restriction training more accessible? Validity of a low-cost blood flow restriction device to estimate arterial occlusion pressure. J Strength Cond Res 37(8): 1581-1587, 2023-Evidence indicates that low-load resistance training with blood flow restriction (BFR) results in comparable gains in muscle mass and muscle strength as high-load resistance training without BFR. Low-load BFR training is a promising tool for areas such as rehabilitation because individuals are exposed to low mechanical stress. However, BFR training is only safe and effective when the cuff pressure is individually adjusted to the arterial occlusion pressure (AOP). Generally, thresholds for AOP are typically determined with sophisticated laboratory material, including Doppler ultrasound and tourniquet systems. Therefore, this study investigated the validity of a low-cost BFR product with automatic AOP assessment (AirBands International) compared with the gold standard for determining the individual AOP. Valid measurements were obtained at the arms and legs in 104 healthy volunteers. For the arms ( n = 49), a Bland-Altman analysis revealed a mean difference of 7 ± 13 mm Hg between the 2 methods, with slightly higher pressure levels for the gold standard (131 ± 14 mm Hg) than for the low-cost device (125 ± 17 mm Hg). For the legs ( n = 55), the low-cost device reached its maximum pressure capacity in 70% of subjects during AOP identification, making the results on the legs unreliable. Although the low-cost device is a valid tool for identifying the individual AOP in the arms, the device cannot be recommended for use at the legs because of its limited pressure capacity. When using the low-cost device for BFR training at the arms, it is recommended to apply the cuff pressure to 60% of the individual AOP to meet current BFR training guidelines., (Copyright © 2023 National Strength and Conditioning Association.)

Background: The high proportion of people with overweight and obesity has become a worldwide problem in recent decades, mainly due to health consequences, such as cardiovascular diseases, neoplasia, and type 2 diabetes mellitus. Regarding effective countermeasures, the digitization of health services offers numerous potentials, which, however, have not yet been sufficiently evaluated. Web-based health programs are becoming increasingly interactive and can provide individuals with effective long-term weight management support., Objective: The purpose of this randomized controlled clinical trial was to evaluate the effectiveness of an interactive web-based weight loss program on anthropometric, cardiometabolic, and behavioral variables and to compare it with a noninteractive web-based weight loss program., Methods: The randomized controlled trial included people who were aged between 18 and 65 years (mean 48.92, SD 11.17 years) and had a BMI of 27.5 to 34.9 kg/m 2 (mean 30.71, SD 2.13 kg/m 2 ). Participants (n=153) were assigned to either (1) an interactive and fully automated web-based health program (intervention) or (2) a noninteractive web-based health program (control). The intervention program focused on dietary energy density and allowed for dietary documentation with appropriate feedback on energy density and nutrients. The control group only received information on weight loss and energy density, but the website did not contain interactive content. Examinations were performed at baseline (t0), at the end of the 12-week intervention (t1), and at 6 months (t2) and 12 months (t3) thereafter. The primary outcome was body weight. The secondary outcomes were cardiometabolic variables as well as dietary and physical activity behaviors. Robust linear mixed models were used to evaluate the primary and secondary outcomes., Results: The intervention group showed significant improvements in anthropometric variables, such as body weight (P=.004), waist circumference (P=.002), and fat mass (P=.02), compared with the control group over the course of the study. The mean weight loss after the 12-month follow-up was 4.18 kg (4.7%) in the intervention group versus 1.29 kg (1.5%) in the control group compared with the initial weight. The results of the nutritional analysis showed that the energy density concept was significantly better implemented in the intervention group. Significant differences in cardiometabolic variables were not detected between the 2 groups., Conclusions: The interactive web-based health program was effective in reducing body weight and improving body composition in adults with overweight and obesity. However, these improvements were not associated with relevant changes in cardiometabolic variables, although it should be noted that the study population was predominantly metabolically healthy., Trial Registration: German Clinical Trials Register DRKS00020249; https://drks.de/search/en/trial/DRKS00020249., International Registered Report Identifier (irrid): RR2-10.3390/ijerph19031393., (©Jan Kohl, Judith Brame, Christoph Centner, Ramona Wurst, Reinhard Fuchs, Matthias Sehlbrede, Iris Tinsel, Phillip Maiwald, Urs Alexander Fichtner, Christoph Armbruster, Erik Farin-Glattacker, Albert Gollhofer, Daniel König. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 27.06.2023.)

Background: Occupational reintegration after anterior cruciate ligament (ACL) rupture is an important clinical issue including economic and health-related perspectives. This study aims to develop and validate a clinical prediction model of return to work in patients with ACL reconstruction surgery considering evidence-based clinical, anthropometric and occupational factors., Methods: Data of 562 patients with an ACL rupture receiving an arthroscopic ACL reconstruction were used for analysis. A model for the binary outcome of experiencing an inability to work period of less or more than 14 days (model 1), and a model for finding predictor variables that are linearly associated with a continuous longer inability to work period of over 14 days (model 2) was calculated. Pre-operative determinants including patient characteristics and peri-operative factors were used as predictors for both models., Results: For model 1, the highest increase in odds was observed for the occupational type of work, followed by injury of the medial collateral ligament together with partial weight bearing. Small protective effects were observed for female sex, meniscal suture and work with light occupational strain. The type of occupational work, together with revision surgery, a longer duration of limited range of motion and the presence of cartilage therapy were risk factors for longer inability to work. Discrimination and calibration statistics were satisfactory in internal validation., Conclusion: Within the framework of clinical consideration, these prediction models will serve as an estimator for patients, their treating physicians and the socioeconomic partners to forecast the individual cost and benefit of ACL injury., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Purpose: Recent evidence indicates that low-load blood flow restriction (LL-BFR) training elicits an anabolic response in tendinous tissue. The purpose of the present study was to investigate the hypertrophic pattern induced in the Achilles tendon by LL-BFR, in comparison with the regional hypertrophy typically observed with conventional high-load (HL) resistance training., Methods: N = 40 male participants were randomly and concealed allocated to one of two groups: LL-BFR training (20-35% one-repetition maximum/1RM) or HL training (70-85% 1RM). The training was completed three times per week for a total of 14 weeks. Before and after the training period, Achilles tendon morphology was assessed using magnetic resonance imaging along the entire tendon length. Additionally, dynamic strength measures of the plantar flexors were evaluated., Results: In line with previous findings, dynamic plantar flexion strength was improved to a comparable extent in both groups (LL-BFR: 43.6%; HL: 43.5%). The results also confirmed significant increases in Achilles tendon cross-sectional area with LL-BFR (+5.2%). Moreover, they revealed that the hypertrophic pattern obtained with LL-BFR was similar to regional changes seen with conventional HL training., Conclusion: The present findings point towards the notion that despite the low loads being applied, LL-BFR training induces Achilles tendon hypertrophy by potentiating anabolic responses in the same regions as with conventional high-load training. Future studies are needed to (i) focus on the potential mechanisms underlying these tendon morphology changes and (ii) apply and evaluate LL-BFR training in clinical populations to validate these results in rehabilitative settings., (© 2023 The Authors. Scandinavian Journal of Medicine & Science In Sports published by John Wiley & Sons Ltd.)

The article is concerned with the after-effects of social stress on work performance. In a lab-based experiment, seventy participants were assigned to either a stress condition or a no-stress condition. In the stress condition, participants received fake negative performance feedback and they were ostracised by two confederates of the experimenter. Participants carried out the following tasks: attention and divergent creativity. The effects of social stress were examined at three levels: performance after-effects on unscheduled probe tasks, extra-role behaviour and subjective operator state. The manipulation check confirmed that participants experienced social stress. The results showed after-effects of social stress for some forms of extra-role behaviour (i.e. spontaneous reactions) and for the accuracy component of attention. Furthermore, social stress was found to increase negative affect and to reduce self-esteem. The findings point to the importance of assessing different types of after-effects rather than limiting the methodological approach to instant effects on performance. Practitioner summary: The study aimed to examine the multiple effects of social stress. Social stress resulted in increased negative affect and lower self-esteem. Furthermore, social stress was found to reduce the propensity of humans to show extra-role behaviour (i.e. providing spontaneous help to others).

Background: Muscle strain injuries (MSIs) in the hamstrings are among the most prevalent injuries in elite soccer. We aimed to examine the relation between biomechanical maladaptation in eccentric strength and neuromuscular factors separated by their time and frequency domains., Methods: 20 elite soccer players with a previous history of unilateral MSI in the M. biceps femoris (BF) long head and 20 without MSI participated. Knee flexion torques, rate of torque development (RTD) and electromyographic signals (EMG) of the BF, the M. semitendinosus (SMT) and knee extensors were obtained during unilateral maximal eccentric knee flexions performed at slow (30°/s) and fast (120°/s) angular speeds. Root mean squares and mean power frequency (MF) was calculated., Results: In the group with a history of MSI, reduced maximal eccentric flexion torque (slow eccentrics -8±11, p<0.05; fast eccentrics -18±13 N*m, p<0.05) and RTD (-33±28 N*m/s, p<0.05; -95±47 N*m/s, p<0.05) concomitantly occurred with diminished agonistic myoelectrical activities (-4±5% of MVC, p<0.05; -10±7% of MVC, p<0.05) and MFs (-24±13 Hz, p<0.05; -24±18 Hz, p<0.05) in the BF. Simultaneously, antagonistic myoelectric activity was elevated (+4±3% of MVC, p<0.05; +3±3% of MVC, p<0.05) in MSI affected legs as compared to unaffected legs for both eccentric contractions. Deficits in myoelectrical activity (r2 = 0.715, p<0.05; r2 = 0.601, p<0.05) and MF (r2 = 0.484, p<0.05; r2 = 0.622, p<0.05) correlated with deficits in maximal torque in the affected leg in the MSI group. Analysis of SMT demonstrated no significant differences., Conclusion: Positive relationships between neuromuscular deficits and the reduced eccentric strength profile underpin neuronal inhibition after MSI. This persistent involvement of dysfunctional synergist and antagonist neural hamstring function in strength weakness is of clinical relevance in sports medicine for prevention and rehabilitation., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Ritzmann et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Secondary anterior cruciate ligament (ACL) ruptures are a relevant clinical concern after surgical treatment of a primary ACL rupture. However, there is a lack of scientific evidence related to the role of muscle strength prior to revision surgery in a second ACL rupture. The aim of this study was to assess differences in knee extensor and flexor strength in patients before primary and secondary ACL reconstruction compared to healthy controls., Methods: In total, n = 69 age, weight and sex matched individuals were included in the study: n = 23 patients with isolated primary ACL rupture, n = 23 with secondary ACL rupture, and n = 23 matched healthy controls. Maximal isokinetic knee extension and flexion torque normalized to body mass was assessed for both legs., Results: For patients with secondary ACL ruptures, torques were reduced in the non-injured (extension: 1.94 Nm/kg vs. 2.46 Nm/kg, p < 0.05, flexion: 1.25 Nm/kg vs. 1.59 Nm/kg, p < 0.05) and the injured leg (extension: 1.70 Nm/kg vs. 2.46 Nm/kg, p < 0.05, flexion: 1.14 Nm/kg vs. 1.59 Nm/kg, p < 0.05) compared to healthy controls. For patients with a primary ACL rupture torques were reduced in the non-injured (extension: 1.92 Nm/kg vs. 2.46 Nm/kg, p < 0.05, flexion: 1.24 Nm/kg vs. 1.59 Nm/kg, p < 0.05) and the injured leg (extension: 1.38 Nm/kg vs. 2.46 Nm/kg, p < 0.05, flexion: 1.01 Nm/kg vs. 1.59 Nm/kg, p < 0.05) compared to healthy controls. There were no differences between patients with primary and secondary ruptures, except of the knee extension on the injured leg showing higher values after a secondary ACL rupture (1.38 Nm/kg vs. 1.70 Nm/kg, p < 0.05)., Conclusions: The findings indicate that maximal knee torques were significantly reduced in patients with primary and secondary ACL ruptures before surgical reconstruction for the non-injured and injured leg as compared to healthy controls. Further investigations are needed to assess strength abilities before and after a second revision within a prospective design., (© 2022. The Author(s).)

The purpose of this study was to investigate the effect of specific collagen peptides (SCP) combined with resistance training (RT) on changes in tendinous and muscular properties. In a randomized, placebo-controlled study, 40 healthy male volunteers (age: 26.3 ± 4.0 years) completed a 14 weeks high-load resistance training program. One group received a daily dosage of 5g SCP while the other group received 5g of a placebo (PLA) supplement. Changes in Achilles tendon cross-sectional area (CSA), tendon stiffness, muscular strength, and thickness of the plantar flexors were measured. The SCP supplementation led to a significantly (p = 0.002) greater increase in tendon CSA (+11.0%) compared with the PLA group (+4.7%). Moreover, the statistical analysis revealed a significantly (p = 0.014) greater increase in muscle thickness in the SCP group (+7.3%) compared with the PLA group (+2.7%). Finally, tendon stiffness and muscle strength increased in both groups, with no statistical difference between the groups. In conclusion, the current study shows that the supplementation of specific collagen peptides combined with RT is associated with a greater hypertrophy in tendinous and muscular structures than RT alone in young physically active men. These effects might play a role in reducing tendon stress (i.e., deposition of collagen in load-bearing structures) during daily activities., (© 2022 The Authors. Scandinavian Journal of Medicine & Science In Sports published by John Wiley & Sons Ltd.)

Context: Hop tests play an important role in the rehabilitation process after injuries. A comparison of the jumping distances of both extremities allows for an evaluation of the injured limb. In the conventional cross-over hop test for distance, the jump width (medial vs. lateral) that the athlete has to cross during the jump is not standardised and therefore highly variable. This affects the absolute jump length in each jump series., Hypothesis: Modifying the test may reduce the jump length variance between test series of an athlete as well as the test-dependent variations in the cross-over hop for distance., Methods: N = 47 athletes from the German and French national Judo youth teams were included in the study (age: 15.3 years ± 13-17). A modified version of the cross-over hop for distance was developed with a cross-over width of 50 cm and a fixed landing zone of 10 cm. The jump lengths of the conventional test and the modified test were documented. The change in jump length variations of the two sexes were compared., Results: The mean value of the coefficient of variation decreased significantly from 4.09 % to 2.83 % (p < 0.01) due to the test modification. This resulted in an absolute improvement in accuracy of 1.26 % and a relative improvement of 30.8 %. A comparison of the limb symmetry index between the conventional and the modified cross-over hop for distance revealed no significant differences., Conclusion: The modified cross-over hop for distance showed a significantly lower variation in jump lengths compared with the conventional cross-over hop for distance. As a result, more accurate statements can be made regarding the patient's return-to-competition progress., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

The coronavirus disease 2019 (COVID-19) pandemic has induced unhealthy lifestyles, particularly an increase in overweight and obesity, which have been shown to be associated with an increased risk of unfavorable COVID-19 outcomes. Web-based health programs could be a helpful measure, especially in times of severe restrictions. Therefore, the present study aimed to investigate the effects of regular attendance in a 12-week web-based weight loss program on COVIDAge, a new construct for risk assessment of COVID-19, and lifestyle-related cardiometabolic risk factors. N = 92 subjects with overweight and obesity (50.0 ± 10.8 years, 76.1% females, 30.5 ± 2.1 kg/m 2 ) of this randomized controlled trial, which were assigned to an interactive (ONLINE: intervention group) or non-interactive (CON: control group) web-based weight loss program, were included in the data analysis. COVIDAge and cardiometabolic risk factors, including anthropometric outcomes, blood pressure, flow-mediated dilatation, and blood parameters, were assessed before and after the 12-week intervention phase. There was a significant group difference in the change of COVIDAge (ONLINE: -4.2%, CON: -1.3%, p = 0.037). The ONLINE group also showed significantly greater reductions in anthropometric outcomes and systolic blood pressure than the CON group ( p < 0.05). To the authors' knowledge, this was the first study investigating the effects of regular attendance in a web-based health program on lifestyle-related risk factors for COVID-19. The results demonstrated that adults with overweight and obesity can improve their COVIDAge and specific cardiometabolic risk factors by using this interactive web-based weight loss program regularly. However, this needs to be confirmed by future studies. This study is registered at the German Clinical Trials Register (DRKS00020249, https://www.drks.de)., Competing Interests: JB and DK report funding from Techniker Krankenkasse for the study design, implementation, and evaluation. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Brame, Centner, Berg, Bartlam, Gollhofer and König.)

Previous evidence suggests that resistance training in combination with specific collagen peptides (CP) improves adaptive responses of the muscular apparatus. Although beneficial effects have been repeatedly demonstrated, the underlying mechanisms are not well understood. Therefore, the primary objective of the present randomized trial was to elucidate differences in gene expression pathways related to skeletal muscle signal transduction following acute high-load resistance exercise with and without CP intake. Recreationally active male participants were equally randomized to high-load leg extension exercise in combination with 15 g CP or placebo (PLA) supplementation. Muscle biopsies from the vastus lateralis muscle were obtained at baseline as well as 1, 4 and 24 h post exercise to investigate gene expression using next generation sequencing analysis. Several important anabolic pathways including PI3K-Akt and MAPK pathways were significantly upregulated at 1 and 4 h post-exercise. Significant between-group differences for both pathways were identified at the 4 h time point demonstrating a more pronounced effect after CP intake. Gene expression related to the mTOR pathway demonstrated a higher visual increase in the CP group compared to PLA by trend, but failed to achieve statistically significant group differences. The current findings revealed a significantly higher upregulation of key anabolic pathways (PI3K-Akt, MAPK) in human skeletal muscle 4 h following an acute resistance training combined with intake of 15 g of specific collagen peptides compared to placebo. Further investigations should examine potential relationships between upregulated gene expression and changes in myofibrillar protein synthesis as well as potential long-term effects on anabolic pathways on the protein level., Competing Interests: SO is coinventor of patents concerning the use of collagen peptides. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Centner, Jerger, Mallard, Herrmann, Varfolomeeva, Gollhofer, Oesser, Sticht, Gretz, Aagaard, Nielsen, Frandsen, Suetta, Gollhofer and König.)

Introduction: Low-load resistance training with blood flow restriction (LL-BFR) has emerged as a viable alternative to conventional high-load (HL) resistance training regimens. Despite increasing evidence confirming comparable muscle adaptations between LL-BFR and HL resistance exercise, only very little is known about tendinous mechanical and morphological adaptations after LL-BFR. Therefore, the aim of the present study was to examine the effects of 14 wk of LL-BFR and HL training on patellar tendon adaptations., Methods: Twenty-nine recreationally active male participants were randomly allocated into the following two groups: LL-BFR resistance training (20%-35% one-repetition maximum (1RM)) or HL resistance training (70%-85% 1RM). Both groups trained three times per week for 14 wk. One week before and after the intervention, patellar tendon mechanical and morphological properties were assessed via ultrasound and magnetic resonance imaging. In addition, changes in muscle cross-sectional area were quantified by magnetic resonance imaging and muscle strength via dynamic 1RM measurements., Results: The findings demonstrated that both LL-BFR and HL training resulted in comparable changes in patellar tendon stiffness (LL-BFR: +25.2%, P = 0.003; HL: +22.5%, P = 0.024) without significant differences between groups. Similar increases in tendon cross-sectional area were observed in HL and LL-BFR. Muscle mass and strength also significantly increased in both groups but were not statistically different between HL (+38%) and LL-BFR (+34%), except for knee extension 1RM where higher changes were seen in LL-BFR., Conclusions: The present results support the notion that both HL and LL-BFR cause substantial changes in patellar tendon properties, and the magnitude of changes is not significantly different between conditions. Further studies that examine the physiological mechanisms underlying the altered tendon properties after LL-BFR training are needed., (Copyright © 2021 by the American College of Sports Medicine.)

Objective: To compare the short- and long-term effects of low-load resistance training with blood-flow restriction (LL-BFR) versus low- (LL-RT) or high- (HL-RT) load resistance training with free blood flow on myoelectric activity and investigate the differences between failure (exercise performed to volitional failure) and nonfailure (exercise not performed to volitional failure) protocols., Data Sources: We identified sources by searching the MEDLINE, PubMed, CINAHL, Web of Science, CENTRAL, Scopus, SPORTDiscus, and PEDro electronic databases., Study Selection: We screened the titles and abstracts of 1048 articles using our inclusion criteria. A total of 39 articles were selected for further analysis., Data Extraction: Two reviewers independently assessed the methodologic quality of each study and extracted the data. A meta-analytic approach was used to compute standardized mean differences (SMDs) ± 95% CIs. Subgroup analyses were conducted for both failure and nonfailure protocols., Data Synthesis: The search identified 39 articles that met the inclusion criteria. Regarding the short-term effects, LL-BFR increased muscle excitability compared with LL-RT during nonfailure protocols (SMD = 0.61; 95% CI = 0.34, 0.88), whereas HL-RT increased muscle excitability compared with LL-BFR during failure (SMD = -0.61; 95% CI = -1.01, -0.21) and nonfailure (SMD = -1.13; 95% CI = -1.94, -0.33) protocols. Concerning the long-term effects, LL-BFR increased muscle excitability compared with LL-RT during exercises performed to failure (SMD = 1.09; 95% CI = 0.39, 1.79)., Conclusions: Greater short-term muscle excitability levels were observed in LL-BFR than in LL-RT during nonfailure protocols. Conversely, greater muscle excitability was present during HL-RT than LL-BFR, regardless of volitional failure. Furthermore, LL-BFR performed to failure increased muscle excitability in the long term compared with LL-RT., (© by the National Athletic Trainers' Association, Inc.)

Bioactive peptides are physiologically active peptides mostly derived from proteins following gastrointestinal digestion, fermentation or hydrolysis by proteolytic enzymes. It has been shown that bioactive peptides can be resorbed in their intact form and have repeatedly been shown to have a positive effect on health-related parameters such as hypertension, dyslipoproteinemia, inflammation and oxidative stress. In recent years, there has been increasing evidence that biologically active peptides could also play an important role in sports nutrition. Current studies have shown that bioactive peptides could have a positive impact on changes in body composition and muscular performance, reduce muscle damage following exercise and induce beneficial adaptions within the connective tissue. In the following overview, potential mechanisms as well as possible limitations regarding the sports-related effect of bioactive peptides and their potential mechanisms are presented and discussed. In addition, practical applications will be discussed on how bioactive peptides can be integrated into a nutritional approach in sports to enhance athletic performance as well as prevent injuries and improve the rehabilitation process.

Exhaustive exercise can induce excessive generation of reactive oxygen species (ROS), which may enhance oxidative stress levels. Although physiological levels are crucial for optimal cell signaling and exercise adaptations, higher concentrations have been demonstrated to damage macromolecules and thus facilitate detrimental effects. Besides single dosages of antioxidants, whole diets rich in antioxidants are gaining more attention due to their practicality and multicomponent ingredients. The purpose of this narrative review is to summarize the current state of research on this topic and present recent advances regarding the antioxidant effects of whole dietary strategies on exercise-induced oxidative stress in humans. The following electronic databases were searched from inception to February 2021: PubMed, Scope and Web of Science. Twenty-eight studies were included in this narrative review and demonstrated the scavenging effects of exercise-induced ROS generation, oxidative stress markers, inflammatory markers and antioxidant capacity, with only one study not confirming such positive effects. Although the literature is still scarce about the effects of whole dietary strategies on exercise-induced oxidative stress, the majority of the studies demonstrated favorable effects. Nevertheless, the protocols are still very heterogeneous and further systematically designed studies are needed to strengthen the evidence.