80 research outputs found
Morphometric characteristics of "Tinca Gobba Dorata del Pianalto"
Forty six T3 tench from 55 to 100 g, were examined in order to set up a first database on morphological traits. Linear (total, fork, head, trunk, caudal peduncle, muscular body and tail length, height, thickness and circumference) and ponderal (total body, viscera, liver and gonad weight) parameters have been measured. Several morphometric indexes were calculated for each sex. The results showed there was no significant difference for K value between sexes. The relationship between C and M can be described with a quadratic regression (R2=0.81)
PDO cheeses from Piedmont (NW Italy): amount and variability of fatty acids of nutritional interest.
Both a single sacral marker and the whole-body center of mass accurately estimate peak vertical ground reaction force in running.
While running, the human body absorbs repetitive shocks with every step. These shocks can be quantified by the peak vertical ground reaction force (F <sub>v,max</sub> ). To measure so, using a force plate is the gold standard method (GSM), but not always at hand. In this case, a motion capture system might be an alternative if it accurately estimates F <sub>v,max</sub> .
The purpose of this study was to estimate F <sub>v,max</sub> based on motion capture data and validate the obtained estimates with force plate-based measures.
One hundred and fifteen runners participated at this study and ran at 9, 11, and 13 km/h. Force data (1000 Hz) and whole-body kinematics (200 Hz) were acquired with an instrumented treadmill and an optoelectronic system, respectively. The vertical ground reaction force was reconstructed from either the whole-body center of mass (COM-M) or sacral marker (SACR-M) accelerations, calculated as the second derivative of their respective positions, and further low-pass filtered using several cutoff frequencies (2-20 Hz) and a fourth-order Butterworth filter.
The most accurate estimations of F <sub>v,max</sub> were obtained using 5 and 4 Hz cutoff frequencies for the filtering of COM and sacral marker accelerations, respectively. GSM, COM-M, and SACR-M were not significantly different at 11 km/h but were at 9 and 13 km/h. The comparison between GSM and COM-M or SACR-M for each speed depicted root mean square error (RMSE) smaller or equal to 0.17BW (≤6.5 %) and no systematic bias at 11 km/h but small systematic biases at 9 and 13 km/h (≤0.09 BW). COM-M gave systematic biases three times smaller than SACR-M and two times smaller RMSE.
The findings of this study support the use of either COM-M or SACR-M using data filtered at 5 and 4 Hz, respectively, to estimate F <sub>v,max</sub> during level treadmill runs at endurance speeds
A Single Sacral-Mounted Inertial Measurement Unit to Estimate Peak Vertical Ground Reaction Force, Contact Time, and Flight Time in Running.
Peak vertical ground reaction force (Fz,max), contact time (tc), and flight time (tf) are key variables of running biomechanics. The gold standard method (GSM) to measure these variables is a force plate. However, a force plate is not always at hand and not very portable overground. In such situation, the vertical acceleration signal recorded by an inertial measurement unit (IMU) might be used to estimate Fz,max, tc, and tf. Hence, the first purpose of this study was to propose a method that used data recorded by a single sacral-mounted IMU (IMU method: IMUM) to estimate Fz,max. The second aim of this study was to estimate tc and tf using the same IMU data. The vertical acceleration threshold of an already existing IMUM was modified to detect foot-strike and toe-off events instead of effective foot-strike and toe-off events. Thus, tc and tf estimations were obtained instead of effective contact and flight time estimations. One hundred runners ran at 9, 11, and 13 km/h. IMU data (208 Hz) and force data (200 Hz) were acquired by a sacral-mounted IMU and an instrumented treadmill, respectively. The errors obtained when comparing Fz,max, tc, and tf estimated using the IMUM to Fz,max, tc, and tf measured using the GSM were comparable to the errors obtained using previously published methods. In fact, a root mean square error (RMSE) of 0.15 BW (6%) was obtained for Fz,max while a RMSE of 20 ms was reported for both tc and tf (8% and 18%, respectively). Moreover, even though small systematic biases of 0.07 BW for Fz,max and 13 ms for tc and tf were reported, the RMSEs were smaller than the smallest real differences [Fz,max: 0.28 BW (11%), tc: 32.0 ms (13%), and tf: 32.0 ms (30%)], indicating no clinically important difference between the GSM and IMUM. Therefore, these results support the use of the IMUM to estimate Fz,max, tc, and tf for level treadmill runs at low running speeds, especially because an IMU has the advantage to be low-cost and portable and therefore seems very practical for coaches and healthcare professionals
Accurate estimation of peak vertical ground reaction force using the duty factor in level treadmill running.
This study aimed to 1) construct a statistical model (SMM) based on the duty factor (DF) to estimate the peak vertical ground reaction force (F <sub>v,max</sub> ) and 2) to compare the estimated F <sub>v,max</sub> to force plate gold standard (GSM). One hundred and fifteen runners ran at 9, 11, and 13km/h. Force (1000Hz) and kinematic (200Hz) data were acquired with an instrumented treadmill and an optoelectronic system, respectively, to assess force-plate and kinematic based DFs. SMM linearly relates F <sub>v,max</sub> to the inverse of DF because DF was analytically associated to the inverse of the average vertical force during ground contact time and the latter was very highly correlated to F <sub>v,max</sub> . No systematic bias and a 4% root mean square error (RMSE) were reported between GSM and SMM using force-plate based DF values when considering all running speeds together. Using kinematic based DF values, SMM reported a systematic but small bias (0.05BW) and a 5% RMSE when considering all running speeds together. These findings support the use of SMM to estimate F <sub>v,max</sub> during level treadmill runs at endurance speeds if underlying DF values are accurately measured
Use of electronic nose to discriminate meats from bulls fed diet with or without flaxseed inclusion and subjected to different aging periods
Changes in pasture and cow milk compositions during a summer transhumance in the western Italian Alps
The changes occurring in pasture and milk compositions during summer grazing were studied following a transhumance of a dairy cattle herd in the western Italian Alps. During three consecutive grazing periods (P1, P2, and P3) the cows exploited, in sequence, mountain pastures located at 1200-1260 m a.s.l. (A1), alpine pastures at 2000-2200 m a.s.l. (A2), and then returned to A1 pastures. The botanical and nutritional compositions of pastures, as well as cow milk yield, gross composition and fatty acid (FA) profi le were assessed during the transhumance. Within the pastures, a cluster analysis allowed the recognition of five vegetation types and seven vegetation sub-types; their allocation and plant species composition differed among the exploited grazing areas. The average Pastoral Values were signifi cantly higher in the mountain (A1P1, A1P3) than in the alpine pastures (A2P2) due to the abundance of high- and medium-quality forage species such as Dactylis glomerata L., Polygonum bistorta L., and Festuca rubra s.l.. Nevertheless, the nutritional quality of the herbage offered to the animals did not differ between A1P1 and A2P2, while it was significantly higher in A1P3 due to a younger vegetation phenological stage. The nutritional parameters were found to be correlated to the pasture botanical composition and phenology: organic matter digestibility and net energy for lactation were correlated negatively to the phenological stage and the Specific Contribution (SC) of Poaceae and positively to the SC of Fabaceae and Asteraceae. Milk yield significantly declined while milk protein increased during the grazing season, following the advance of cows’ stage of lactation. Milk fat and lactose percentages did not vary significantly among the grazing periods. The same was also observed for milk FA, with the exception of palmitic acid, whose level was lower in A2P2 if compared to the other two periods. Significant correlations were found between the percentages of some FA in milk and the SC of the main botanical families of the grazed pastures. In particular, linoleic acid was negatively correlated with the SC of Poaceae and positively correlated with the SC of Fabaceae. Results showed that the changes in the nutritional composition of pastures depended on variations in pasture botanical composition and phenology at the time of grazing, and that such factors concurred with animal-related factors in affecting milk quality during the grazing season
Does Characterizing Global Running Pattern Help to Prescribe Individualized Strength Training in Recreational Runners?
This study aimed to determine if concurrent endurance and strength training that matches the global running pattern would be more effective in increasing running economy (RE) than non-matched training. The global running pattern of 37 recreational runners was determined using the Volodalen <sup>®</sup> method as being aerial (AER) or terrestrial (TER). Strength training consisted of endurance running training and either plyometric (PLY) or dynamic weight training (DWT). Runners were randomly assigned to a matched (n = 18; DWT for TER, PLY for AER) or non-matched (n = 19; DWT for AER, PLY for TER) 8 weeks concurrent training program. RE, maximal oxygen uptake V̇O <sub>2</sub> max) and peak treadmill speed at V̇O <sub>2</sub> max (PTS) were measured before and after the training intervention. None of the tested performance related variables depicted a significant group effect or interaction effect between training and grouping (p ≥ 0.436). However, a significant increase in RE, V̇O <sub>2</sub> max, and PTS (p ≤ 0.003) was found after the training intervention. No difference in number of responders between matched and non-matched groups was observed for any of the performance related variables (p ≥ 0.248). In recreational runners, prescribing PLT or DWT according to the global running pattern of individuals, in addition to endurance training, did not lead to greater improvements in RE
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