Reliability and sensitivity to change of post-match physical performance measures in elite youth soccer players.

Introduction: To effectively monitor post-match changes in physical performance, valid, reliable and practical measures which are sensitive to change are required. This study aimed to quantify test-retest reliability and sensitivity to change of a range of physical performance measures recorded during an isometric posterior chain (IPC) lower-limb muscle test and a countermovement jump (CMJ) test. Methods: Eighteen Italian Serie A academy soccer players performed three IPC repetitions per limb and five CMJ trials in 4 testing sessions. Test-retest reliability was evaluated between two testing sessions seven days apart using typical error of measurement, coefficient of variation and intraclass correlation coefficient. Sensitivity to change was assessed on two additional testing sessions performed before and immediately after a soccer match through Hedges' g effect size (g) and comparisons to typical error. Results: Absolute reliability (coefficient of variations) ranged from 1.5 to 8.8%. IPC and CMJ measures demonstrated moderate to excellent relative reliability (intraclass correlation coefficients ranged from 0.70 to 0.98). A wide range of physical performance measures showed significant alterations post-match (p < 0.05; g: small to moderate). IPC peak force and torque, CMJ reactive strength index modified, CMJ eccentric forces (mean breaking force, mean deceleration force, peak force, force at zero velocity) and CMJ mean power measures had post-match changes greater than their typical variation, demonstrating acceptable sensitivity in detecting performance changes at post-match. Discussion: IPC peak force and torque, CMJ reactive strength index modified, CMJ eccentric phase forces and CMJ mean power were found to be both reliable and sensitive to change, and thus may be appropriate for monitoring post-match neuromuscular performance in youth soccer population.

Variations in athletic performance with occlusal splint in track and field athletes: a randomized clinical trial.

BACKGROUND: Several studies have been proposed with the aim to demonstrate correlations between the dento-mandibular apparatus and the skeletal muscle system of the human body even in regions distant from the oral cavity. However, a definite conclusion cannot be drawn. The aim of this paper is to demonstrate a possible correlation between dental occlusion and sport performances in track and field athletes. METHODS: Sixteen track and field athletes were enrolled for the study and were randomly divided in three groups: Untreated control group, Placebo group (with a lower plaque without occlusal coverage) and Treated group (with occlusal splint). Changes in sprint and jump performance were assessed on a weekly basis for 5 consecutive weeks, during which athletes had to wear oral devices, except for the first week of baseline, for at least 3 trainings lasting 2 hours per week . All participants performed the countermovement jump (CMJ), the drop jump (DJ), the 10m and 30m sprint tests, always on the same day on the week. RESULTS: No statistically significant difference resulted between Control group and Placebo group and between Control group and Treated group. However, it was possible to observe a clinical improvement of measurements obtained, especially for CMJ, 10m and 30m sprint tests. No variation neither statistical neither clinical was observed in DJ test analysis. CONCLUSIONS: Even if statistically it was not possible to demonstrate an improvement in sport performance, most of the athlete analyzed showed better results during training session with occlusal splint compared to athlete without occlusal splint, in countermovement jump, in 10m and 30m sprint tests.

An Overview on Microfluidic Systems for Nucleic Acids Extraction from Human Raw Samples.

Nucleic acid (NA) extraction is a basic step for genetic analysis, from scientific research to diagnostic and forensic applications. It aims at preparing samples for its application with biomolecular technologies such as isothermal and non-isothermal amplification, hybridization, electrophoresis, Sanger sequencing and next-generation sequencing. Multiple steps are involved in NA collection from raw samples, including cell separation from the rest of the specimen, cell lysis, NA isolation and release. Typically, this process needs molecular biology facilities, specialized instrumentation and labor-intensive operations. Microfluidic devices have been developed to analyze NA samples with high efficacy and sensitivity. In this context, the integration within the chip of the sample preparation phase is crucial to leverage the promise of portable, fast, user-friendly and economic point-of-care solutions. This review presents an overview of existing lab-on-a-chip (LOC) solutions designed to provide automated NA extraction from human raw biological fluids, such as whole blood, excreta (urine and feces), saliva. It mainly focuses on LOC implementation aspects, aiming to describe a detailed panorama of strategies implemented for different human raw sample preparations.

Training Load, Neuromuscular Readiness, and Perceptual Fatigue Profile in Youth Elite Long-Jump Athletes.

PURPOSE: To describe and identify individual trends and changes in training load, neuromuscular readiness, and perceptual fatigue measures in 2 youth elite long jumpers, finalists at the European Athletics U18 (Under 18) Championships (athlete A, female, age 16.5 y, long-jump record 6.25 m; athlete B, male, age 16.0 y, long-jump record 7.28 m). METHODS: Data were collected from both training sessions and athletics competitions during a 16-week period, divided into a preparation (weeks 1-8) and a competitive phase (weeks 9-16). Training load was computed through training diaries (training time, sprint, jumping, and weights volume). The countermovement jump and the 10-to-5 repeated-jump test were executed on a weekly basis to assess neuromuscular readiness, and perceptual fatigue measures were collected through a wellness questionnaire. Statistical analysis was conducted using a magnitude-based decisions approach. RESULTS: The results highlighted a decrease in training load during the competitive period with moderate to large differences for training time, sprint, and jump volume. Moreover, data showed an upward trend and very likely higher scores in vertical-jump performance across the competitive phase together with a very likely lower perceptual fatigue. CONCLUSIONS: This scenario seemed to be favorable to achieve competition performance very close to the personal record during the competitive season. This study provided an example of application of a comprehensive monitoring system with young athletes involved in track-and-field jumping events.

Effects of a combined strength and conditioning training program on physical abilities in adolescent male basketball players.

BACKGROUND: The aim of this study was to evaluate the effects of an in-season strength and conditioning program on physical abilities in under-16 sub-elite basketball players. METHODS: Sixteen young male basketball players were assessed using countermovement jump (CMJ), squat jump (SJ), 10-meters sprint and Pro Agility Test, before and after an 8-week in-season strength and conditioning program. Both the control group (BASK; N.=7) and the experimental group (SC; N.=9) were involved in regular basketball practice; additionally, the SC group performed 4 sessions per week of training intervention considering postmatch days and prior days to next match. The training protocol consisted of three components: a stabilization block, a neuromuscular/strength block (i.e. circuit of mobility, plyometric, coordination, reaction, and stability exercises) and a power block (i.e. resisted movement training performed with VertiMax V6 platform). RESULTS: Substantial improvements in CMJ (likely; d=0.30-0.47) were found in both groups. Moreover, the SC group displayed substantial increase in SJ (likely; d=0.07-1.26) and also in 10 m-sprint (d=-0.13-1.34). The between-group analysis also revealed greater improvements for the SC group in 10-m sprint (d=1.37) and SJ (d=0.50). CONCLUSIONS: In -season regular basketball practice plus strength and conditioning training program can lead to a greater improvement on jumping and sprinting abilities in male young basketball players comparing to the regular basketball training.

Elite national athletes reach their peak performance later than non-elite in sprints and throwing events.

OBJECTIVES: The aim of this study was to describe and analyse the performance career trajectories for Italian athletes that participated in sprint, hurdles, discus throw, and shot-put athletics events. DESIGN: Retrospective study, data collected between 1994 and 2014. METHODS: A total of 5929 athletes (female: n=2977, 50.2%) were included in the study. The age of entering competition and personal best performance was identified in the official competition records. Personal best performances were ranked in percentiles and top-level athletes were considered those in the highest 4% of the performance distribution. RESULTS: Overall, when controlling for the age of entering competition, top-level athletes reached their personal best later (i.e., around 23-25 years old) for all events compared to the rest of the athletes. Moreover, regression analysis showed that entering competitions later was linked to better performances during adulthood. Also, only 17%-26% [90% CI] of the top-level adult athletes were considered as such when they were 14-17 years old. CONCLUSIONS: Together, these findings suggest that early sport success is not a strong predictor of top-level performance at senior level. Entering sport-specific competitions later and lengthening the sports career at beyond 23-25 years of age may be important factors to reach top-level performance in sprint and throwing events.

Career Performance Trajectories in Track and Field Jumping Events from Youth to Senior Success: The Importance of Learning and Development.

INTRODUCTION: The idea that early sport success can be detrimental for long-term sport performance is still under debate. Therefore, the aims of this study were to examine the career trajectories of Italian high and long jumpers to provide a better understanding of performance development in jumping events. METHODS: The official long-jump and high-jump rankings of the Italian Track and Field Federation were collected from the age of 12 to career termination, for both genders from the year 1994 to 2014. Top-level athletes were identified as those with a percentile of their personal best performance between 97 and 100. RESULTS: The age of entering competitions of top-level athletes was not different than the rest of the athletic population, whereas top-level athletes performed their personal best later than the rest of the athletes. Top-level athletes showed an overall higher rate of improvement in performance from the age of 13 to the age of 18 years when compared to all other individuals. Only 10-25% of the top-level adult athletes were top-level at the age of 16. Around 60% of the top-level young at the age of 16 did not maintain the same level of performance in adulthood. Female high-jump represented an exception from this trend since in this group most top-level young become top-level adult athletes. CONCLUSIONS: These findings suggest that performance before the age of 16 is not a good predictor of adult performance in long and high jump. The annual rate of improvements from 13 to 18 years should be included as a predictor of success rather than performance per se. Coaches should be careful about predicting future success based on performances obtained during youth in jumping events.

Identification of Microsporum canis from dermatophytic pseudomycetoma in paraffin-embedded veterinary specimens using a common PCR protocol.

The effectiveness of a simple PCR protocol performed on paraffin-embedded tissues, obtained from histopathologically and culturally diagnosed cases of dermatophytic pseudomycetoma DPM was tested. The specimens were investigated using previously described primers (DH1L and DH1R) targeting the 18S rDNA gene and amplifying a 183-bp fragment. Microsporum canis was identified from all samples. The PCR protocol described in the present work demonstrated a 100% concordant result comparing the molecular characterisation with phenotypic characterisation of dermatophytes. Molecular biology could represent a valid identification tool in dermatophytic deep infections, when diagnosis cannot be achieved by cultural methods.

Expression and function of Toll-like receptor 2 in canine blood phagocytes.

Toll-like receptors (TLRs) are a family of highly conserved pattern recognition receptors (PRR) of mammals that participate in the activation of innate immune responses against microbial infections. Among these receptors, TLR2 is essential for the recognition of conserved structural components of bacteria, protozoa and fungi. Until now, expression of TLR2 in dogs has not been investigated. In this work we describe a partial sequence of the gene coding for canine TLR2 and show that TLR2 mRNA is constitutively expressed in canine blood PMNs. We also show that stimulation of purified PMNs with lipoteichoic acid (LTA), a ligand of TLR2, leads to the release of proinflammatory chemokine IL-8. Furthermore, TLR2 protein is easily detectable by flow cytometry on the canine peripheral blood granulocyte and monocyte cell surface, and slightly on lymphocytes. These findings suggest that, also in dogs as in humans the initial antibacterial response of PMNs could be elicited through engagement of TLR2.

Mapping the presence of Wolbachia pipientis on the phylogeny of filarial nematodes: evidence for symbiont loss during evolution.

Wolbachia pipientis is a bacterial endosymbiont associated with arthropods and filarial nematodes. In filarial nematodes, W. pipientis has been shown to play an important role in the biology of the host and in the immuno-pathology of filariasis. Several species of filariae, including the most important parasites of humans and animals (e.g. Onchocerca volvulus, Wuchereria bancrofti and Dirofilaria immitis) have been shown to harbour these bacteria. Other filarial species, including an important rodent species (Acanthocheilonema viteae), which has been used as a model for the study of filariasis, do not appear to harbour these symbionts. There are still several open questions about the distribution of W. pipientis in filarial nematodes. Firstly the number of species examined is still limited. Secondly, it is not clear whether the absence of W. pipientis in negative species could represent an ancestral characteristic or the result of a secondary loss. Thirdly, several aspects of the phylogeny of filarial nematodes are still unclear and it is thus difficult to overlay the presence/absence of W. pipientis on a tree representing filarial evolution. Here we present the results of a PCR screening for W. pipientis in 16 species of filariae and related nematodes, representing different families/subfamilies. Evidence for the presence of W. pipientis is reported for five species examined for the first time (representing the genera Litomosoides, Litomosa and Dipetalonema); original results on the absence of this bacterium are reported for nine species; for the remaining two species, we have confirmed the absence of W. pipientis recently reported by other authors. In the positive species, the infecting W. pipientis bacteria have been identified through 16S rDNA gene sequence analysis. In addition to the screening for W. pipientis in 16 species, we have generated phylogenetic reconstructions based on mitochondrial gene sequences (12S rDNA; COI), including a total of 28 filarial species and related spirurid nematodes. The mapping of the presence/absence of W. pipientis on the trees generated indicates that these bacteria have possibly been lost during evolution along some lineages of filarial nematodes.