48 research outputs found

    Core Muscle Activation in Suspension Training Exercises

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    A quantitative observational laboratory study was conducted to characterize and classify core training exercises executed in a suspension modality on the base of muscle activation. In a prospective single-group repeated measures design, seventeen active male participants performed four suspension exercises typically associated with core training (roll-out, bodysaw, pike and knee-tuck). Surface electromyographic signals were recorded from lower and upper parts of rectus abdominis, external oblique, internal oblique, lower and upper parts of erector spinae muscles using concentric bipolar electrodes. The average rectified values of electromyographic signals were normalized with respect to individual maximum voluntary isometric contraction of each muscle. Roll-out exercise showed the highest activation of rectus abdominis and oblique muscles compared to the other exercises. The rectus abdominis and external oblique reached an activation higher than 60% of the maximal voluntary contraction (or very close to that threshold, 55%) in roll-out and bodysaw exercises. Findings from this study allow the selection of suspension core training exercises on the basis of quantitative information about the activation of muscles of interest. Roll-out and bodysaw exercises can be considered as suitable for strength training of rectus abdominis and external oblique muscles

    Heart rate analysis during very deep dives in flooded caves: single case study

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    The purpose of this study is to investigate the heart rate adaptations during deep dave diving with MCCR (mechanical closed circuit rebreather). Previous studies on this matter have not been conducted to the depths reached in this study and most of them have been conducted inside hyperbaric chambers trying to recreate the immersion conditions. The data collection took place during the exploration of two hydrogeological sites by a professional cave diver. The recordings were made using a SCUBAPRO GALILEO SOL® dive computer capable of monitoring the heart rate, with a sampling interval of 0,25 Hz. The data collected confirm a direct relationship between the increase in diving depth and the increase in the detected heart rate

    Effects of nutritional intake on performance in master athletes during an extreme ultra-trail

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    The purpose of our study was to monitor a well-trained master athlete who competed in the race, keeping under review his performance outcomes. TransPyrenea (La Grande Traversee des Pyrenees) is an Ultra Trail 13-16-d race, 866 km long, 53200 meters of elevation gain, performed for the first time in 2016, becoming the longest race in the world. At every checkpoint, a member of the team ascertained total macronutrients intake and body composition. A wearable device was used to monitor glycemia during all the race. The athlete completed the race with an average speed of 2.6 Km/h, including 26 hours and 30 minutes of sleeping. Multiple regression analysis showed that the increase of the speed (β: 0.5 km/h, 95% CI: 0.07 | 1.02 km/h, p-value: 0.035 and β: 1.32 km/h, 95% CI: 0.53 | 2.11 km/h, p-value: 0.004) was related to the increase of one hour of sleep and one kg of weight respectively. This evidence could induce the use of specific nutritional supplements and the analysis of body composition on the management strategies of the race, with eventually the planning of a greater number of hours of sleep to acquire greater speed

    Advances in the genetics of hypertension: The effect of rare variants

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    Worldwide, hypertension still represents a serious health burden with nine million people dying as a consequence of hypertension-related complications. Essential hypertension is a complex trait supported by multifactorial genetic inheritance together with environmental factors. The heritability of blood pressure (BP) is estimated to be 30–50%. A great effort was made to find genetic variants affecting BP levels through Genome-Wide Association Studies (GWAS). This approach relies on the “common disease–common variant” hypothesis and led to the identification of multiple genetic variants which explain, in aggregate, only 2–3% of the genetic variance of hypertension. Part of the missing genetic information could be caused by variants too rare to be detected by GWAS. The use of exome chips and Next-Generation Sequencing facilitated the discovery of causative variants. Here, we report the advances in the detection of novel rare variants, genes, and/or pathways through the most promising approaches, and the recent statistical tests that have emerged to handle rare variants. We also discuss the need to further support rare novel variants with replication studies within larger consortia and with deeper functional studies to better understand how new genes might improve patient care and the stratification of the response to antihypertensive treatments

    Maxillary molar distalization with aligners in adult patients: a multicenter retrospective study

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    Abstract Background The aim of the present study was to test the hypothesis that bodily maxillary molar distalization was not achievable in aligner orthodontics. Methods Forty lateral cephalograms obtained from 20 non-growing subjects (9 male, 11 female; average age 29.73 years) (group S), who underwent bilateral distalization of their maxillary dentition with Invisalign aligners (Align Technology, Inc., San José, CA, USA), were considered for the study. Skeletal class I or class II malocclusion and a bilateral end-to-end class II molar relationship were the main inclusion criteria. Cephalograms were taken at two time points: (T0) pretreatment and (T2) post-treatment. Treatment changes were evaluated between the time points using 39 variables by means of paired t test. The level of significance was set at P < 0.05. Reproducibility of measurements was assessed by the intraclass correlation coefficient (ICC). Results The mean treatment time was 24.3 ± 4.2 months. At the post-treatment point, the first molar moved distally 2.25 mm without significant tipping (P = 0.27) and vertical movements (P = 0.43). The second molar distalization was 2.52 mm without significant tipping (P = 0.056) and vertical movements (P = 0.25). No significant movements were detected on the lower arch. SN^GoGn and SPP^GoGn angles showed no significant differences between pre- and post-treatment cephalograms (P = 0.22 and P = 0.85, respectively). Conclusions Aligner therapy in association with composite attachments and class II elastics can distalize maxillary first molars by 2.25 mm without significant tipping and vertical movements of the crown. No changes to the facial height were revealed

    Scanning electron microscopy evaluation of aligner fit on teeth

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    The fitting of aligners on anchorage teeth is a crucial factor in clear aligner orthodontics. The purpose of this experimental study was to evaluate the fitting of two aligner systems, Invisalign and CA-Clear Aligner, using scanning electron microscopy (SEM)

    Root resorption during orthodontic treatment with Invisalign&#174;: a radiometric study

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    Abstract Background Root resorption (RR) is described as a permanent loss of tooth structure from the root apex. Many reports in the literature indicate that orthodontically treated patients are more likely to have severe apical root shortening, interesting mostly maxillary, followed by mandibular incisors. The aim of the study was to investigate the incidence and severity of RR in adult patients treated with aligners. The study group consisted of 71 class I adult healthy patients (mean age 32.8 ± 12.7) treated with aligners (Invisalign®, Align Technologies, Santa Clara, CA, USA). All incisors, canines, upper first premolars, and first molars were assessed. Root and crown lengths of 1083 teeth were measured in panoramic radiographs at the beginning (T0) and at the end (T1) of clear aligner therapy. Individual root-crown ratio (RCR) of each tooth and therefore the relative changes of RCR (rRCR) were determined. A decrease of rRCR was assessed as a reduction of the root length during treatment. Results All patients had a minimum of one teeth affected with a reduction of root length, on average 6.38 ± 2.28 teeth per patient. Forty one, 81% of the 1083, measured teeth presented a reduction of the pre-treatment root length. A reduction in percentage of >0% up to 10% was found in 25.94% (n = 281), a distinct reduction of >10% up to 20% in 12.18% (n = 132) of the sample. 3.69% (n = 40) of the teeth were affected with a considerable reduction (>20%). Conclusions Orthodontic treatment with Invisalign® aligners could lead to RR. However, its incidence resulted to be very similar to that described for orthodontic light forces, with an average percentage of RR < 10% of the original root length
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