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Real-time networks are traditionally built on proprietary standards, resulting in a interoperability issues between different real-time netork implementations and traditional data networks mainly used in back office operations. Continuity and supplier independence are a cause of concern with current proprietary real-time networks. This project evaluates the capability of providing real-time traffic over switched Ethernet with EDF scheduling algorithm implemented at both the switch and the node. By using OMNET simulation tool at packet level, it is shown that the EDF implementation in switched Ethernet can guarantee real-time traffic over the network and at the same time supporting non real-time traffic.

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We observed 82 healthy subjects, from both sexes, aged between 19 and 77 years. All subjects performed two different tests: for being scientifically acknowledged, the first one was used as a reference and it was a stress test (CPX). During the entire test, heart rate and gas exchange were recorded continuously; the second, the actual object of this study, was a submaximal test (TOP). Only heart rate was recorded continuously. The main purpose was to determinate an index of physical fitness as result of TOP. CPX test allowed us to individuate anaerobic threshold. We used an incremental protocol of 10/20 Watt/min, different by age. For our TOP test we used an RHC400 UPRIGHT BIKE, by Air Machine. Each subject was monitored for heart frequency. After 2 minutes of resting period there was a first step: 3 minutes of pedalling at a constant rate of 60 RPM, (40 watts for elder subjects and 60 watts for the younger ones). Then, the subject was allowed to rest for a recovery phase of 5 minutes. Third and last step consisted of 3 minutes of pedalling again at 60 RPM but now set to 60 watts for elder subjects and 80 watts for the young subjects. Finally another five minutes of recovery. A good correlation was found between TOP and CPX results especially between punctua l heart rate reserve (HRR’) and anaerobic threshold parameters such as Watt, VO2, VCO2 . HRR’ was obtained by subtracting maximal heart rate during TOP from maximal theoretic heart rate (206,9-(0,67*age)). Data were analyzed through cluster analysis in order to obtain 3 homogeneous groups. The first group contains the least fit subjects (inactive, women, elderly). The other groups contain the “average fit” and the fittest subjects (active, men, younger). Concordance between test resulted in 83,23%. Afterwards, a linear combinations of the most relevant variables gave us a formula to classify people in the correct group. The most relevant result is that this submaximal test is able to discriminate subjects with different physical condition and to provide information (index) about physical fitness through HRR’. Compared to a traditional incremental stress test, the very low load of TOP, short duration and extended resting period, make this new method suitable to very different people. To better define the TOP index, it is necessary to enlarge our subject sample especially by diversifying the age range.

Running economy (RE), i.e. the oxygen consumption at a given submaximal speed, is an important determinant of endurance running performance. So far, investigators have widely attempted to individuate the factors affecting RE in competitive athletes, focusing mainly on the relationships between RE and running biomechanics. However, the current results are inconsistent and a clear mechanical profile of an economic runner has not been yet established. The present work aimed to better understand how the running technique influences RE in sub-elite middle-distance runners by investigating the biomechanical parameters acting on RE and the underlying mechanisms. Special emphasis was given to accounting for intra-individual variability in RE at different speeds and to assessing track running rather than treadmill running. In Study One, a factor analysis was used to reduce the 30 considered mechanical parameters to few global descriptors of the running mechanics. Then, a biomechanical comparison between economic and non economic runners and a multiple regression analysis (with RE as criterion variable and mechanical indices as independent variables) were performed. It was found that a better RE was associated to higher knee and ankle flexion in the support phase, and that the combination of seven individuated mechanical measures explains ∼72% of the variability in RE. In Study Two, a mathematical model predicting RE a priori from the rate of force production, originally developed and used in the field of comparative biology, was adapted and tested in competitive athletes. The model showed a very good fit (R2=0.86). In conclusion, the results of this dissertation suggest that the very complex interrelationships among the mechanical parameters affecting RE may be successfully dealt with through multivariate statistical analyses and the application of theoretical mathematical models. Thanks to these results, coaches are provided with useful tools to assess the biomechanical profile of their athletes. Thus, individual weaknesses in the running technique may be identified and removed, with the ultimate goal to improve RE.

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