Objectives: The aims of this study were (1) to quantify and compare the load of a professional football team's training days and matches and (2) to compare training of nonstarters the day after the match with regular training of starters and nonstarters. Methods: On-field training load during in-season training days (categorized as days before match day, i.e., MD minus) and 3 friendly matches were recorded using alocal positioning measurement system. Results: Mixed linear models showed lower load when training approached match day. Relative to match values (100%), training values for running (52 -20%; MD-4 -MD-1) and high-speed running (38 -15%) were lower than for total distance (67 -35%), and all considerably lower than match values. On average, medium and high accelerations and decelerations during training were more similar to match values (90 -39%). Load during nonstarters training was lower than during regular training for almost all variables on MD-4 and several high-intensity variables on MD-3 and MD-2. Conclusions: The results highlight that acceleration and deceleration measures complement more commonly used external load variables based on distance and speed. Furthermore, nonstarters are potentially under-loaded compared to starters, especially in terms of (high-speed) running.

Purpose: A local position measurement (LPM) system can accurately track the distance covered and the average speed of whole body movements. However, for the quantification of a soccer player's workload, accelerations rather than positions or speeds are essential. The main purpose of the current study was therefore to determine the accuracy of LPM in measuring average and peak accelerations for a broad range of (maximal) soccerspecific movements. Methods: Twelve male amateur soccer players performed 8 movements (categorized in straight runs and runs involving a sudden change in direction of 90° or 180°) at 3 intensities (jog, submaximal, maximal). Position-related parameters recorded with LPM were compared with Vicon motionanalysis data sampled at 100 Hz. The differences between LPM and VICON data were expressed as percentage of the Vicon data. Results: LPM provided reasonably accurate measurements for distance, average speed and peak speed (differences within 2% across all movements and intensities). For average acceleration and deceleration absolute bias and 95% limits of agreement were 0.01 ± 0.36 m/s 2 and 0.02 ± 0.38 m/s 2 , respectively. On average, peak acceleration was overestimated (0.48 ± 1.27 m/s 2 ) by LPM, while peak deceleration was underestimated (0.32 ± 1.17 m/s 2 ). Conclusion: LPM accuracy appears acceptable for most measurements of average acceleration and deceleration, but for peak acceleration and deceleration accuracy is limited. However, when these error margins are kept in mind, the system may be used in practice for quantifying average accelerations and parameters such as summed accelerations or time spent in acceleration zones.

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A major challenge in the assessment of brain injury and its relationship to the ensuing functional deficits is the accurate delineation of the areas of damage. Here, we test the hypothesis that the anatomical distribution pattern of activated microglia, a normally dormant population of resident brain macrophages, can be used as a surrogate marker of neuronal injury not only at the primary lesion site but also in the antero- and retrograde projection areas of the lesioned neurones. Two patients with asymmetrical herpes simplex encephalitis were serially scanned 6 and 12 months after the acute illness using PET with [11C] (R)-PK11195, a marker of activated microglia/brain macrophages. The evolving structural changes in the brain were measured by volumetric MRI and compared with the pattern of [11C](R)-PK11195 binding. Corresponding to the clinically observed cognitive deficits, quantitative [11C](R)-PK11195-PET revealed highly significant signal increases within the affected limbic system and additionally in areas connected to the limbic system by neural pathways, including the lingual gyrus in the occipital lobe and the inferior parietal lobe, which had normal morphology on structural MRI. The increased [11C](R)-PK11195 binding, signifying the presence of activated microglia, persisted many months (>12) after antiviral treatment. Cortical areas that showed early high [11C](R)-PK11195 binding subsequently underwent atrophy. These observations demonstrate that in vivo imaging of activated microglia/brain macrophages provides a dynamic measure of active tissue changes following an acute focal lesion. Importantly, the glial tissue response in the wake of neuronal damage is protracted and widespread within the confines of the affected distributed neural system and can be related to the long-term functional deficits.

Shuttle running raised the player's energy cost of running compared to constant running at the same average speed. Although actual energy cost of constant running was significantly overestimated by di Prampero's approach using LPM data as input, actual energy cost of shuttle running was significantly underestimated.

In order to determine whether small-sided game (SSG) locomotor performance can serve as a fitness indicator, we (1) compared 6-a-side (6v6) SSG-intensity of players varying in fitness and skill, (2) Although total distance and metabolic power during 6v6-SSG showed good reproducibility (coefficient of variation (CV) <5%), CV was higher (8-14%) for all high-intensity time-motion variables. It was therefore concluded that standardised SSG locomotor performance can not serve be used as a valid and reliable fitness indicator for individual players.

There are many controversies concerning the structural basis of retrograde amnesia (RA). One view is that memories are held briefly within a medial temporal store ("hippocampal complex") before being "consolidated" or reorganised within temporal neocortex and/or networks more widely distributed within the cerebral cortex. An alternative view is that the medial temporal lobes are always involved in the storage and retrieval (reactivation) of autobiographical memories (multiple trace theory). The present study used quantitative magnetic resonance imaging (MRI) in 40 patients with focal pathology/volume loss in different sites, to examine the correlates of impairment on three different measures of RA. The findings supported the view that widespread neural networks are involved in the storage and retrieval of autobiographical and other remote memories. Brain volume measures in critical structures could account for 60% of variance on autobiographical memory measures (for incidents and facts) in diencephalic patients and for 60-68% of variance in patients with frontal lesions. Significant correlations with medial temporal lobe volume were found only in the diencephalic group, in whom they were thought to reflect thalamic changes, but not in patients with herpes encephalitis or hypoxia in whom the temporal lobes were particularly implicated. The latter finding fails to support one of the main predictions of multiple trace theory, as presently expounded.

Only a few studies have analysed the accuracy of position detection systems. All of them analysed distances and velocities, which are the outcome of calculations based on x,y positions. The objective of this study was to analyse the accuracy of dynamic x,y position measurement of a radar- and an image-based system in football. One and two runners performed five different runs on four different locations on a football pitch. X,y positions recorded by the radar-based and the image-based system were compared to x,y positions measured by a Laveg laser device. Accuracies were analysed by means of root mean square error (RMSE). Results showed that the radar-based system detects positions more accurately than the image-based system (P = 0.000). Mean RMSE of the radar-based system was 0.24 m, RMSE of the image-based system was 0.73 m. The image-based system was significantly influenced by the location of the run, whereas the radar-based system was not. Based on the results of this study, we conclude that the radar-based system is more valid in detecting x,y positions than the image-based system. Future studies should take advantage of the new test design which allows more precise statements on the accuracy of a position detection system.