Relationship between subjective and external training load variables in youth soccer players.

Purpose: To quantify and describe relationships between subjective and external measures of training load in professional youth soccer players. Methods: Data from differential ratings of perceived exertion and seven measures of external training load were collected from 20 professional youth soccer players over a 46-week season. Relationships were described by repeated measures correlation, principal component analysis and factor analysis with oblimin rotation. Results: Significant positive (0.44 ≤ r ≤ 0.99; p< 0.001) within-individual correlations were obtained across dRPE and all external training load measures Correlation magnitudes were found to decrease when training load variables were expressed per minute. Principal component analysis provided two components that described 83.3% of variance. The first component, which described 72.9% of variance, was heavily loaded by all measures of training load, whilst the second component which described 10.4% of the variance, appeared to have a split between objective and subjective measures of volume and intensity. Exploratory Factor Analysis identified four theoretical factors with correlations between factors ranging from 0.5 to 0.8 These factors could be theoretically described as; objective volume, subjective volume, objective running and objective high intensity measures. Removing dRPE measures from analysis altered the structure of the model, providing a three factor solution. Conclusions: Differential RPE measures are significantly correlated with a range of external training load measures and with each other. More in-depth analysis showed that dRPE measures were highly related to each other, suggesting that, in this population, they would provide practitioners with similar information. Further analysis provided characteristic groupings of variables

The influence of season phase on multivariate load relationships in professional youth soccer.

The purpose of this research was to assess relationships between subjective and external measures of training load in professional youth footballers, whilst accounting for the effect of the stage of the season. Data for ratings of perceived exertion (RPE) and seven global positioning systems (GPS) derived measures were collected from 20 players (age=17.4±1.3yrs, height=178.0±8.1 cm, mass=71.8±7.2 kg) across a 47-week season. The season was categorised by a pre-season phase, and two competitive phases (Comp1, Comp2). The structure of the data were investigated using principal component analysis. An extraction criterion of component with eigenvalues ≥1.0 was used. Two components were retained for the pre-season period explaining a cumulative variance of 77.1%. Single components were retained for both Comp1 and Comp2 explaining 73.3% and 74.3% of variance, respectively. Identification of single components may suggest that measures are related and can be used interchangeably, however these interpretations should be considered with caution. The identification of multiple components in the pre-season phase suggests that univariate measures may not be sufficient when considering load experienced. These results suggest that factoring load based on measures of volume and intensity should be considered

Neutron Scattering in Normal and Deuterated Polyethylene

The one‐ and two‐phonon amplitude‐weighted directional frequency functions are calculated for normal and deuterated crystalline polyethylene. These results are compared to previously measured frequency spectra for stretch‐oriented normal polyethylene and to new measurements on deuterated polyethylene. In addition, the Debye‐Waller factors are calculated for oriented polyethylene and compared with elastic‐scattering data.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70915/2/JCPSA6-48-2-912-1.pd

Theodicy and End-of-Life Care

Acknowledgments The section on Islamic perspective is contributed by information provided by Imranali Panjwani, Tutor in Theology & Religious Studies, King's College London.Peer reviewedPublisher PD

Physiological and perceptual responses of youth soccer players to an intensified period of competition.

Intensified periods of competition create large increase in physical workload and can expose soccer players to numerous playing styles. The purpose of the study was to investigate the response of youth soccer players to an intensified period of competition and assess whether initial fitness influenced outcomes. Elite males across two consecutive years (n1=18, n2=18) were assessed for lower body strength and high-intensity endurance. Objective and subjective measures of fatigue were collected throughout five-day international tournaments using countermovement jumps (CMJ), a perceptual wellness questionnaire and match GPS data. Mixed effects models quantified the effects of time and fitness on outcomes. In general, results were consistent across both years. No significant interaction effects were obtained between time and fitness variables for any outcome (χ_4^2≤ 6.5; p≥ .225). CMJ height and power remained consistent across both tournaments (χ_4^2≤ 5.3; p≥ .262). In contrast, significant (χ_4^2≥ 17.7; p< .003) effects of time were obtained for GPS data with metrics exhibiting U-shape patterns with values returning to initial levels during final games. Greater variation was obtained for perceptual wellness data, however, responses to general muscle soreness and stress levels showed consistent decreases across both years (χ_4^2 ≥ 12.7; p≤ .013). Practitioners should be aware that basic measures collected from CMJ and GPS data may not be sensitive to fatigue accrued in youth soccer players across intensified periods of competition. In contrast, simple perceptual measures including general muscle soreness and stress may be more sensitive and assist with implementation of active recovery or load management strategies

Shift of percolation thresholds for epidemic spread between static and dynamic small-world networks

The aim of the study was to compare the epidemic spread on static and dynamic small-world networks. The network was constructed as a 2-dimensional Watts-Strogatz model (500x500 square lattice with additional shortcuts), and the dynamics involved rewiring shortcuts in every time step of the epidemic spread. The model of the epidemic is SIR with latency time of 3 time steps. The behaviour of the epidemic was checked over the range of shortcut probability per underlying bond 0-0.5. The quantity of interest was percolation threshold for the epidemic spread, for which numerical results were checked against an approximate analytical model. We find a significant lowering of percolation thresholds for the dynamic network in the parameter range given. The result shows that the behaviour of the epidemic on dynamic network is that of a static small world with the number of shortcuts increased by 20.7 +/- 1.4%, while the overall qualitative behaviour stays the same. We derive corrections to the analytical model which account for the effect. For both dynamic and static small-world we observe suppression of the average epidemic size dependence on network size in comparison with finite-size scaling known for regular lattice. We also study the effect of dynamics for several rewiring rates relative to latency time of the disease.Comment: 13 pages, 6 figure

The Ursinus Weekly, November 24, 1958

Y holds seminar Nov. 19; Marriage problem is topic • Fireside chats to be held Dec. 3 at prof\u27s home • C. Carpenter has poem published in anthology • Administrative regulation • Mayes, Francis \u2762 representatives to MSGA • New pledges announced by Alpha Psi Omega • De Gaulle and France topic at second Forum of Fall semester • Who\u27s who honors 12 leading Ursinus seniors • Senior Ball to be held at Sunnybrook Dec. 5 • W.S.G.A. presents plaque to winning frosh team • Editorial: Thanksgiving • Letters to the editor • Review: Joan of Lorraine • Slightly allegorical • U.C. soccermen lose last three games; Finish 2-6-1 • Prospects for U.C. basketball team looking up • Varsity hockey finishes with 4-2-1; J.V. is 6-0-1 • Football squad drops two games 12-0, 34-6 • Sorority bids • American hist. students begin tour program • Fine art of datinghttps://digitalcommons.ursinus.edu/weekly/1372/thumbnail.jp

Comparative Analysis of the Impact of Frequency on the Radius of Curvature of Single and Double Rounded Edge Hill Obstruction

In this paper, comparative analysis of the impact of frequency on the radius of curvature of single and double rounded edge hill obstruction is studied, particularly when the International Telecommunication Union (ITU) recommendation 526 version 13 method is used to compute the radius of curvature. The study is conducted with two  path profiles of  microwave links, one  with isolated  single edged hilltop and a second profile  with isolated  double edged hilltop. The frequencies considered are  from the 1.5 GHz in the L-band   to 36GHz in the K-band. The radius of curvature decreases with frequency in the case of single edged hilltop whereas the radius of curvature increases with frequency in the case of double edge hilltop. Essentially, other factors are responsible for determining whether the radius of curvature will increase or decrease with frequency.  One of such factors is the occultation distance. For all the frequencies considered, the occultation distance is 80.923 m for the single edged hilltop and 532.203m for the double edged hilltop. Further studies are therefore required to ascertain the factors that determine the exact impact of frequency on the radius of curvature for rounded edge obstructions