DOES THE SITTING POSITION INFLUENCE CLAY TARGET SHOOTING PERFORMANCE IN ATHLETES WITH A MOTOR IMPAIRMENT?

Olympic trap clay target shooting (CTS) is currently performed by motor impaired individuals (MII), but not yet included in the International Paralympic Committee endorsement. This study aimed at supporting the development of a classification model that divides athletes competing in standing and sitting postures. Two groups of 5 standing and 5 sitting MII athletes were recruited for an instrumented CTS task execution. During competition, sitting athletes showed a lower rate of success with respect to the standing ones only for targets requiring wider ranges of motion, possibly due to fatigue. Their predominant use of upper body movements implies an adapted technique to reach a good performance, testified by a smoother movement, a lower peak accelerations at the gun tip, a smaller range for all absolute and relative rotations, and a different muscle activity

Hyperbaric exposure and oxidative Stress in occupational activities (HEOxS): the study protocol

Background: Hyperbaric exposure (HE) is proven to be a stressor to several mechanisms in living cells. Even if after homeostasis restoration, harmful effects are expected, in particular a presence of free radicals. These latter are the stimulus to negative phenomenon as inflammation or cancer. In Italy, with 7500 km of sea shores, a large quantity of workers is exposed to HE during occupational activities. A deep knowledge of HE and bodily effects is not well defined; hence a multidisciplinary assessment of risk is needed. To detect one or more indicators of HE a research group is organised, under the INAIL sponsorship. The research project focused on the oxidative stress (OxS) and this paper details on the possible protocol to estimate, with a large amount of techniques on several human liquids, the relationship between OxS and HE. Specific attention will be paid to identify confounding factors and their influence. Methods: Blood and urine will be sampled. Several lab techniques will be performed on samples, both targeted, to measure the level of well-known biomarkers, and untargeted. Regard the formers: products of oxidation of DNA and RNA in urine; inflammation and temperature cytokines and protein carbonyles in blood. Untargeted evaluation will be performed for a metabolomics analysis in urine. Confounding factors: temperature, body fat, fitness, allergies and dietary habits. These factors will be assessed, directly or indirectly, prior and after HE. The final scope of the project is to determine one or more indicators that relates to HE in hits twofold nature: depth and duration. Conclusion: The relationship between OxS and HE is not deeply investigated and literature proposes diverging results. The project aims to define the time dependence of biomarkers related to OxS, to rise knowledge in risk assessment in workers exposed to HE

Multilevel Upper Body Movement Control during Gait in Children with Cerebral Palsy.

Upper body movements during walking provide information about balance control and gait stability. Typically developing (TD) children normally present a progressive decrease of accelerations from the pelvis to the head, whereas children with cerebral palsy (CP) exhibit a general increase of upper body accelerations. However, the literature describing how they are transmitted from the pelvis to the head is lacking. This study proposes a multilevel motion sensor approach to characterize upper body accelerations and how they propagate from pelvis to head in children with CP, comparing with their TD peers. Two age- and gender-matched groups of 20 children performed a 10m walking test at self-selected speed while wearing three magneto-inertial sensors located at pelvis, sternum, and head levels. The root mean square value of the accelerations at each level was computed in a local anatomical frame and its variation from lower to upper levels was described using attenuation coefficients. Between-group differences were assessed performing an ANCOVA, while the mutual dependence between acceleration components and the relationship between biomechanical parameters and typical clinical scores were investigated using Regression Analysis and Spearman's Correlation, respectively (α = 0.05). New insights were obtained on how the CP group managed the transmission of accelerations through the upper body. Despite a significant reduction of the acceleration from pelvis to sternum, children with CP do not compensate for large accelerations, which are greater than in TD children. Furthermore, those with CP showed negative sternum-to-head attenuations, in agreement with the documented rigidity of the head-trunk system observed in this population. In addition, the estimated parameters proved to correlate with the scores used in daily clinical practice. The proposed multilevel approach was fruitful in highlighting CP-TD gait differences, supported the in-field quantitative gait assessment in children with CP and might prove beneficial to designing innovative intervention protocols based on pelvis stabilization

Usefulness of Magnetoinertial Wearable Devices in Neurorehabilitation of Children with Cerebral Palsy

Background. Despite the increasing use of wearable magnetoinertial measurement units (MIMUs) for gait analysis, the efficacy of MIMU-based assessment for planning rehabilitation has not been adequately documented yet. Methods. The usefulness of a MIMU-based assessment was evaluated comparing the data acquired by three MIMUs located at the pelvis, sternum, and head levels in 12 children with cerebral palsy (CP, age: 2–9 years) and 12 age-matched children with typical development (TD). Gait stability was quantified in terms of acceleration attenuation coefficients from pelvis to head, pelvis to sternum, and sternum to head. Children with CP were randomly divided in two groups: in the first group (CPI), MIMU-based parameters were used by therapists for planning patient-tailored rehabilitation programs, whereas in the second group (CPB), therapists were blind to the MIMU-based assessment results. Both CPI and CPB were tested before and after the relevant neurorehabilitation program. Ad hoc questionnaires were also administered to therapists of the CPI group to assess the degree of usefulness perceived about the information provided by the MIMU-based assessment. Results. Significant differences were found between children with CP and those with TD for the acceleration attenuation coefficient from pelvis to head (p=0.048) and from pelvis to sternum (p=0.021). After neurorehabilitation, this last parameter increased more in CPI (35%) than in CPB (6%, p=0.017 for the interaction group per time). The results of the questionnaires showed that therapists agreed with the usability (100% judged it as “easy to use”) and usefulness of the MIMU-based assessment in defining patient-oriented interventions (87%). Conclusions. There is a large debate in literature about the efficacy of classical gait analysis that should be enlarged to new technological approaches, such as that based on MIMUs. This study is a first proof of concept about the efficacy of this approach for neurorehabilitation of children with CP

Estimating orientation using magnetic and inertial sensors and different sensor fusion approaches: accuracy assessment in manual and locomotion tasks

Magnetic and inertial measurement units are an emerging technology to obtain 3D orientation of body segments in human movement analysis. In this respect, sensor fusion is used to limit the drift errors resulting from the gyroscope data integration by exploiting accelerometer and magnetic aiding sensors. The present study aims at investigating the effectiveness of sensor fusion methods under different experimental conditions. Manual and locomotion tasks, differing in time duration, measurement volume, presence/absence of static phases, and out-of-plane movements, were performed by six subjects, and recorded by one unit located on the forearm or the lower trunk, respectively. Two sensor fusion methods, representative of the stochastic (Extended Kalman Filter) and complementary (Non-linear observer) filtering, were selected, and their accuracy was assessed in terms of attitude (pitch and roll angles) and heading (yaw angle) errors using stereophotogrammetric data as a reference. The sensor fusion approaches provided significantly more accurate results than gyroscope data integration. Accuracy improved mostly for heading and when the movement exhibited stationary phases, evenly distributed 3D rotations, it occurred in a small volume, and its duration was greater than approximately 20 s. These results were independent from the specific sensor fusion method used. Practice guidelines for improving the outcome accuracy are provided

Body density estimation from multi-frequency Bioelectrical Impedance Analysis measurements

Introduction: Air plethysmography analysis is a method to measure the human body density (D) and ables to evaluate the body composition. This tool is emerging as a convenient alternative to the hydrostatic weighing. D allows estimation of the Human Fat Mass percentage using typical regression relations (see Siri, 1956). The objectives of the study is to define the relationship between Bioelectrical parameters obtained by Multifrequency Biolectrical Analysis (MF-BIA) and D. Methods: 25 healthy subjects (35 ± 8.2 anni; 1.72 ± 0.08 m; 78.6 ± 15.3 kg) both genders have been enrolled and D measurements have been collected with an Air plethysmography (BODPOD, Cosmed, Italia). Moreover, MF-BIA parameters as Z, PA, Rx and Xc at 5, 10, 50, 100, 250 kHz have been measured (Human in Touch, DSmedica, Italia). Multiply regression analysis has been performed between D and MF-BIA parameters and backward identification method has been used as selection criterion (p < 0.05; software SPSS, IBM, USA). Results: Statistical analysis reports as PA at 50 and 100 kHz are the MF-BIA parameters with best prediction value of D as measured by BODPOD (p < 0.005). The main results (expressed as mean + SD) are: D: 1.038 ± 0.029; D(PA50): 1.041 ± 0.019; D(PA100): 1.036 ± 0.019. Data with an R2adj of 0.394 and 0.442 and a SE of 0.022 and 0.021 for PA50 and PA100, respectively. Conclusions: Phase Angle at 50 kHz and 100 kHz are accurate D predictors. It would seem that the D estimation are slightly higher and lower with PA50 and PA100 respectively. Future investigations on a greater subject number are required to confirm present results and to increase the estimation precision. Moreover, similar studies are necessary to recognise MF-BIA and D relation also in particular categories as well as Obese and diabetic patients

Gait parameters obtained for both the TD and CP groups.

<p>Gait parameters obtained for both the TD and CP groups.</p

Sensor location and axes orientation of the Magneto-Inertial Measurement Units (MIMUs) attached on the children’s body segments.

<p>H: head level; S: sternum level; P: pelvis.</p