Self-reported training variables are poor predictors of laboratory measures in cyclists.

Purpose: Cycling is an activity that depends on a range of physiological attributes, as well as genetic, dietary, lifestyle and training factors. The aim of this study was to determine what self-reported training-related factors (e.g. intensity, frequency, supervision, etc) might predict laboratory-measured physiological and performance characteristics of a heterogeneous group of male and female self-classified cyclists. Methods: Forty-eight male and fourteen female cyclists completed all aspects of the study including a training questionnaire, incremental cycling test to determine maximal oxygen uptake (VO2max), 30-s Wingate test and a 4-km cycling time-trial. Principle component analysis and LASSO regression modelling were used to analyse laboratory-measures and training variables and the predictive capacity of the latter. Results: Total distance covered across all intensities was the only training variable included in most bootstrap models (63.8%), although the actual contribution was very low with a median f2 effect size equal to 0.01. Self-reported classification of cycling level was weakly correlated to guideline classification of relative VO2max in men (r=0.396, p=0.004), but not women (r=0.024, p=0.925). Conclusions: Self-reported training variables were poor predictors of laboratory-based physiological and performance variables in this heterogeneous group of cyclists. Total distance covered was the only training variable included in most regression models, but the predictive capability of outcomes was low. This suggests that most of these self-report variables are not useful pre-screening tools for categorising non-elite cyclists or raises the potential that non-elite cyclists cannot accurately quantify their own training intensities. Researchers and coaches should be wary that self-reported classification may not directly reflect the level of the cyclist

Comparison of four methods of surface roughness assessment of corneal stromal bed after lamellar cutting

International audienc

Influence of multi-wavelength ultrafast laser texturing and autoclave sterilization on titanium alloy-based surface wettability

International audienceTitanium alloys are widely used in bio-medical applications for their excellent bio-compatibility and superior mechanical strength. On the other hand, femtosecond laser processing is a robust versatile and industrial method widely used for surface functionalization. In this work, laser-induced periodic surface structures (LIPSS) on titanium alloy (Ti6Al4V) using different laser wavelengths of 1030 nm (IR), 515 nm (Green) and 257 nm (UV) were created and their surface wettability (physical parameter correlated with cell adhesion) was studied, in relation to sterilization process. The contact angle over LIPSS was smaller than over polished samples, with Green and UV LIPSS presenting contact angles inferior to 20 $$^\circ$$ ∘ and a superior stability to sterilization process

Dietary β-alanine intake assessed by food records does not associate with muscle carnosine content in healthy, active, omnivorous men and women.

β-alanine (BA) is one of the most widely used sport supplements, due to its capacity to improve high intensity exercise performance by increasing muscle carnosine (MCarn) content, and consequently, the buffering capacity of the muscle. BA is also available in a variety of animal foods, but little is currently known about the influence of dietary BA intake on MCarn. The aim of the current study was to compile a detailed summary of available data on the BA content of commonly consumed foods, and to explore whether associations could be detected between self-reported dietary BA intake and skeletal MCarn in a group of 60 healthy, active, omnivorous men and women. Dietary BA intake was assessed via 3-day food records and MCarn content assessed by high performance liquid chromatography. A series of univariate and multivariate linear regression models were used to explore associations between estimated dietary BA and MCarn. No evidence of associations between dietary BA intake and MCarn were identified, with effect sizes close to zero calculated from models accounting for key demographic variables (f2 ≤ 0.02 for all analyses). These findings suggest that capacity to increase MCarn via dietary strategies may be limited, and that supplementation may be required to induce increases of the magnitude required to improve performance

The bone biomarker response to an acute bout of exercise: a systematic review with meta-analysis.

Circulating biomarkers are often used to investigate the bone response to an acute bout of exercise, but heterogeneity in factors such as study design, quality, selected biomarkers and exercise and participant characteristics render it difficult to synthesize and evaluate available evidence. PURPOSE: To quantify the effects of an acute exercise bout on bone biomarkers, along with the influence of potential moderators such as participant, exercise and design characteristics, using a systematic review and meta-analytic approach. METHODS: The protocol was designed in accordance with PRISMA-P guidelines and prospectively published. Seven databases were systematically searched in accordance with pre-defined eligibility criteria. Bayesian three-level hierarchical meta-analysis models were used to explore main effects of acute exercise on bone biomarkers, as well as potential moderating factors. Modelled effect sizes were interpreted according to three metrics namely: A) Evidence of an effect (defined by whether, or how much of, the CrI included zero); B) The size of that effect (threshold values of 0.01, 0.2, 0.5 and 0.8 were used to describe effect sizes as very small, small, medium and large, respectively); and C) The level of certainty in the estimated effect (defined using the GRADE framework). RESULTS: Pooling of outcomes across all designs and categories indicated that an acute bout of exercise increased bone resorption (ES0.5=0.10 [95%CrI: 0.00 to 0.20] and formation (ES0.5=0.05 [95%CrI: 0.01 to 0.08] markers, but the effects were very small and highly variable Moderator analyses revealed the source of some of this variability and indicated that exercise type and impact loading influenced the bone resorptive response. A moderate increase in CTX-1 was observed in response to cycling (ES0.5=0.65 [95%CrI: 0.20 to 0.99]), with greater durations and more work leading to larger CTX-1 increases. CTX-1 response peaked within 15 minutes and 2 hours after the exercise bout. Other exercise types did not influence CTX-1. Changes to all bone formation markers were very small and transient, with the very small increases returning to baseline within 15 minutes of exercise cessation. No major trends for bone formation markers were identified across any of the moderating categories investigated. Certainty of evidence in most outcomes was deemed to be low or very low. CONCLUSION: The large influence of an acute bout of prolonged cycling on the bone resorption marker CTX-1, alongside the lack of a response of any biomarker to resistance or high-impact exercise types, indicate that these biomarkers may be more useful at investigating potentially osteolytic aspects of exercise, and raises questions about their suitability to investigate the osteogenic potential of different exercise types, at least in the short term and in response to a single exercise bout. Certainty in all outcomes was low or very low, due to factors including risk of bias, lack of non-exercise controls, inconsistency, imprecision and small-study effects. Protocol Registration and Publication: This investigation was prospectively registered on the Open Science Framework Registry (https://osf.io/6f8dz) and the full protocol underwent peer-review prior to conducting the investigation

Generic Chemometric Models for Metabolite Concentration Prediction Based on Raman Spectra

Chemometric models for on-line process monitoring have become well established in pharmaceutical bioprocesses. The main drawback is the required calibration effort and the inflexibility regarding system or process changes. So, a recalibration is necessary whenever the process or the setup changes even slightly. With a large and diverse Raman dataset, however, it was possible to generate generic partial least squares regression models to reliably predict the concentrations of important metabolic compounds, such as glucose-, lactate-, and glutamine-indifferent CHO cell cultivations. The data for calibration were collected from various cell cultures from different sites in different companies using different Raman spectrophotometers. In testing, the developed “generic” models were capable of predicting the concentrations of said compounds from a dilution series in FMX-8 mod medium, as well as from an independent CHO cell culture. These spectra were taken with a completely different setup and with different Raman spectrometers, demonstrating the model flexibility. The prediction errors for the tests were mostly in an acceptable range (<10% relative error). This demonstrates that, under the right circumstances and by choosing the calibration data carefully, it is possible to create generic and reliable chemometric models that are transferrable from one process to another without recalibration

MRI-guided adaptive brachytherapy in locally advanced cervical cancer (EMBRACE-I): a multicentre prospective cohort study

Background: The concept of the use of MRI for image-guided adaptive brachytherapy (IGABT) in locally advanced cervical cancer was introduced 20 years ago. Here, we report on EMBRACE-I, which aimed to evaluate local tumour control and morbidity after chemoradiotherapy and MRI-based IGABT. Methods: EMBRACE-I was a prospective, observational, multicentre cohort study. Data from patients from 24 centres in Europe, Asia, and North America were prospectively collected. The inclusion criteria were patients older than 18 years, with biopsy-proven squamous cell carcinoma, adenocarcinoma, or adenosquamous carcinoma of the uterine cervix, The International Federation of Gynecology and Obstetrics (FIGO) stage IB–IVA disease or FIGO stage IVB disease restricted to paraaortic lymph metastasis below the L1–L2 interspace, suitable for curative treatment. Treatment consisted of chemoradiotherapy (weekly intravenous cisplatin 40 mg/m2, 5–6 cycles, 1 day per cycle, plus 45–50 Gy external-beam radiotherapy delivered in 1·8–2 Gy fractions) followed by MRI-based IGABT. The MRI-based IGABT target volume definition and dose reporting was according to Groupe Européen de Curiethérapie European Society for Radiation Oncology recommendations. IGABT dose prescription was open according to institutional practice. Local control and late morbidity were selected as primary endpoints in all patients available for analysis. The study was registered with ClinicalTrials.gov, NCT00920920. Findings: Patient accrual began on July 30, 2008, and closed on Dec 29, 2015. A total of 1416 patients were registered in the database. After exclusion for not meeting patient selection criteria before treatment, being registered but not entered in the database, meeting the exclusion criteria, and being falsely excluded, data from 1341 patients were available for analysis of disease and data from 1251 patients were available for assessment of morbidity outcome. MRI-based IGABT including dose optimisation was done in 1317 (98·2%) of 1341 patients. Median high-risk clinical target volume was 28 cm3 (IQR 20–40) and median minimal dose to 90% of the clinical target volume (D90%) was 90 Gy (IQR 85–94) equi-effective dose in 2 Gy per fraction. At a median follow-up of 51 months (IQR 20–64), actuarial overall 5-year local control was 92% (95% CI 90–93). Actuarial cumulative 5-year incidence of grade 3–5 morbidity was 6·8% (95% CI 5·4–8·6) for genitourinary events, 8·5% (6·9–10·6) for gastrointestinal events, 5·7% (4·3–7·6) for vaginal events, and 3·2% (2·2–4·5) for fistulae. Interpretation: Chemoradiotherapy and MRI-based IGABT result in effective and stable long-term local control across all stages of locally advanced cervical cancer, with a limited severe morbidity per organ. These results represent a positive breakthrough in the treatment of locally advanced cervical cancer, which might be used as a benchmark for clinical practice and all future studies. Funding: Medical University of Vienna, Aarhus University Hospital, Elekta AB, and Varian Medical Systems