Phases of Match-Play in Professional Australian Football: Positional Demands and Match-Related Fatigue.

This study examined the influence of player position and match quarter on activity profiles during the phases of play in Australian Football. Global positioning satellite data was collected for one season from an Australian Football League team for nomadic, key position and ruck players (age: 24.8 ± 4.2 years, body mass: 88.3 ± 8.7 kg, height: 1.88 ± 0.8 m). Separate linear mixed models and effect sizes were used to analyse differences between positions and game quarter within each phase of play for values of distance, speed and metabolic power indices. There were clear differences between positions for low-speed running, high-speed running, total distance and average speed. Nomadic players generally recorded the highest match running outputs, followed by key position players and ruckmen. Within each position, offence and defence involved the highest intensities, followed by contested play and then stoppage periods. Across the four quarters, there were small to large reductions in average speed, high-speed running, high power and energy expenditure during offence, defence and contested play, but not during stoppages. Accordingly, conditioning staff should consider the intermittent intensities of the phases of match-play for each position to optimally prepare players for competition. Reductions in match intensities were evident during active periods of play providing implications for real-time monitoring to optimise the timing of rotations.

Phases of match-play in professional Australian Football: Distribution of physical and technical performance.

The current study aimed to describe the distribution of physical and technical performance during the different phases of play in professional Australian Football. The phases of play (offence, defence, contested play, umpire stoppages, set shots and goal resets) were manually coded from video footage for a single team competing in 18 matches in the Australian Football League. Measures of physical performance including total distance (m), average speed (m · min-1), low-speed running (LSR, <14.4 km h-1), high-speed running (HSR, >14.4 km h-1), accelerations (2.78 m · s-2) and decelerations (-2.78 m · s-2) were derived from each phase of play via global positioning system (GPS) devices. Technical skill data including tackles, handballs and kicks were obtained from a commercial statistics provider and derived from each phase of play. Linear mixed-effects models and effect sizes were used to assess and reflect the differences in physical and technical performance between the six phases of play. Activity and recovery cycles, defined as periods where the ball was in or out of play were also described using mean and 95% confidence intervals. The analysis showed that several similarities existed between offence and defence for physical performance metrics. Contested play involved the highest total distance, LSR, accelerations, decelerations and tackles compared to all other phases. Offence and defence involved the highest average speed and HSR running distances. Handballs and kicks were highest during offence, while tackles were highest during contested play, followed by defence. Activity and recovery cycles involved mean durations of ~110 and ~39 s and average speeds of ~160 and ~84 m · min-1, respectively. The integration of video, GPS and technical skill data can be used to investigate specific phases of Australian Football match-play and subsequently guide match analysis and training design.

Match-play movement and metabolic power demands of elite youth, sub-elite and elite senior Australian footballers.

AIMS: Currently minimal research has quantified physical requirement differences in match-play between youth and senior Australian football players. The aim of the current research was to describe and compare the movement profiles and energy cost of youth, sub-elite and elite senior Australian football match-play. METHODS: Fifty-seven Australian footballers playing in an elite senior 20, sub-elite senior 16 and elite youth competition 21 participated in this study. Distance, speed based indices and metabolic power measures recording via Global Positioning System (GPS) devices were compared across three competition tiers. Kicks and handballs were collected via a commercial statistics provider (Champion Data) and compared across the competition tiers. RESULTS: Youth players recorded less field time (elite: ES = 1.37/sub-elite: ES = 1.68), total distance (elite: ES = 1.64 /sub-elite: ES = 1.55) and high speed running (elite: ES = 0.90/sub-elite: ES = 0.26) compared to the elite and sub-elite players. The average energy cost of elite (ES = 2.19) and sub-elite (ES = 1.58) match-play was significantly higher that youth match-play. CONCLUSIONS: A progressive increase regarding physical demands was evident across AF competition tiers. The findings suggest that sub-elite match-play can provide a viable pathway for youth players to develop physical capacity and technical skills before transitioning to elite senior match-play.

Awareness and compliance with pharmacovigilance requirements amongst UK oncology healthcare professionals.

Since 2013, once a medicine receives marketing authorisation in the European Union, it is labelled with an inverted black triangle indicating all adverse reactions should be reported. Our aim was to explore understanding of the black triangle and compliance with adverse event (AE) reporting requirements by UK oncology healthcare professionals (HCPs). A questionnaire was electronically distributed to oncology pharmacists (P) via the British Oncology Pharmacy Association, to oncologists (O) through the Association of Cancer Physicians and also to nurses (N) via the UK Oncology Nursing Society. Overall, 125 (42 O, 61 P, 22 N) clinicians participated. The purpose of the black triangle was unknown by 26% (55% O, 5% P, 28% N) and 54% did not alter their AE reporting in the presence of a black triangle. Once the black triangle was removed, only 38% were aware which AEs should be reported, 46% did not report all serious AEs for established medicines, including life-threatening or disabling AEs. Reasons for non-reporting were decision making on what to report (45%); time consumed by reporting (41%); AEs perceived as not serious enough (35%) and follow-up process (23%). Understanding of the pharmacovigilance framework among respondent groups was variable. Across all groups, AEs appear substantially under-reported. Reasons identified in the study include the time consuming nature of AE reporting and a lack of understanding around the black triangle and AE reporting process. There is a need to further support HCP education on AE reporting coupled with a review of the current reporting process to ensure maximal engagement.

Phases of match-play in professional Australian Football: Descriptive analysis and reliability assessment.

OBJECTIVES: To examine the frequency and time spent in the phases of Australian Football (AF) match-play and to assess the intra-assessor reliability of coding these phases of match-play. DESIGN: Observational, intra-reliability assessment. METHODS: Video footage of 10 random quarters of AF match-play were coded by a single researcher. Phases of offence, defence, contested play, umpire stoppage, set shot and goal reset were coded using a set of operational definitions. Descriptive statistics were provided for all phases of match-play. Following a 6-month washout period, intra-coder reliability was assessed using typical error of measurement (TEM) and intra-class correlation coefficients (ICC). RESULTS: A quarter of AF match-play involved 128±20 different phases of match-play. The highest proportion of match-play involved contested play (25%), followed by offence (18%), defence (18%) and umpire stoppages (18%). The mean duration of offence, defence, contested play, umpire stoppage, set shot and goal reset were 14, 14, 10, 11, 28 and 47s, respectively. No differences were found between the two coding assessments (p>0.05). ICCs for coding the phases of play demonstrated very high reliability (r=0.902-0.992). TEM of the total time spent in each phase of play represented moderate to good reliability (TEM=1.8-9.3%). Coding of offence, defence and contested play tended to display slightly poorer TEMs than umpire stoppages, set shots and goal resets (TEM=8.1 vs 4.5%). CONCLUSIONS: Researchers can reliably code the phases of AF match-play which may permit the analysis of specific elements of competition.

Differences in Physical Capacity Between Junior and Senior Australian Footballers.

Kelly, SJ, Watsford, ML, Austin, DJ, Spurrs, RW, Pine, MJ, and Rennie, MJ. Differences in physical capacity between junior and senior Australian footballers. J Strength Cond Res 31(11): 3059-3066, 2017-The purpose of this study was to profile and compare anthropometric and physical capacities within elite junior and senior Australian football (AF) players of various chronological ages and stages of athletic development. Seventy-nine players, including junior and senior AF players from one professional club, were profiled using 11 assessments. Junior players were divided into 2 groups based on chronological age (under 16 and 18 years) and senior players according to years since drafted to a professional AF team (1-2 years, 3-7 years, and 8+ years). Parametric data were assessed using a 1-way analysis of variance (ANOVA), whereas nonparametric data were assessed using a Kruskal-Wallis ANOVA. The magnitude difference between players was measured using the Hopkins' effect size (ES). Significant differences were evident between under-16 players and all senior player groups for anthropometric (p = 0.001-0.019/ES = 1.25-2.13), absolute strength (p = 0.001-0.01/ES = 1.82-4.46), and relative strength (p = 0.001-0.027/ES = 0.84-3.55). The under-18 players displayed significantly lower absolute strength (p = 0.001-0.012/ES = 1.82-3.79) and relative strength (p = 0.001-0.027/ES = 0.85-4.00) compared with the 3-7 and 8+ players. Significant differences were evident between the under-16 players and senior player groups for explosive jumping and throwing tests (p = 0.001-0.017/ES = 1.03-2.99). Minimal differences were evident between all player groups for running assessments; however, the under-16 players were significantly slower compared with the 8+ players for the 3-km time trial (p < 0.02/ES = 1.31), whereas both junior player groups covered significantly less distance during the Yo-Yo IR2 (p < 0.02/ES = 1.19 and 1.60). Results of this study display a significant deficit in strength between junior and senior AF players.

Reliability and validity of sports accelerometers during static and dynamic testing.

PURPOSE: To investigate the validity and reliability of accelerometry of the SPI-ProX II dual data logger (GPSports, Canberra, Australia). METHODS: Controlled laboratory assessments determined the accuracy and reproducibility of raw accelerometer data. Intra- and interdevice reliability assessed the ability of the SPI-ProX II accelerometers to repeatedly measure peak gravitational accelerations (g) during impact-based testing. Static and dynamic validity testing assessed the accuracy of SPI-ProX II accelerometers against a criterion-referenced accelerometer. Dynamic validity was assessed over a range of frequencies from 5 to 15 Hz. RESULTS: Intradevice reliability found no differences (P < .05) between 4 SPI-ProX II accelerometers, with a low coefficient of variation (1.87-2.21%). SPI-ProX II accelerometers demonstrated small to medium effect-size (ES) differences (0.10-0.44) between groups and excellent interdevice reliability, with no difference found between units (F = 0.826, P = .484). Validity testing revealed significant differences between devices (P = .001), with high percentage differences (27.5-30.5%) and a large ES (>3.44). CONCLUSIONS: SPI-ProX II accelerometers demonstrated excellent intra- and interaccelerometer reliability. However, static and dynamic validity were poor, and caution is recommended when measuring the absolute magnitude of acceleration, particularly for high-frequency movements. Regular assessment of individual devices is advised, particularly for mechanical damage and signal-drift errors. It is recommended that guidelines be provided by the manufacturer on measuring shifts in the base accelerometer signal, including time frames for assessing accelerometer axis, magnitude of errors, and calibration of accelerometers from a stable reference point.

Professional rugby league positional match-play analysis through the use of global positioning system.

The purpose of this study was to quantify the movement demands of all 9 individual playing positions in professional rugby league. The movement demands of 135 professional rugby league players were recorded during 28 National Rugby League games in 2011, using a nondifferential 5 Hz global positioning system. The mean total distances covered in a game for fullback, wing, center, five-eight, halfback, hooker, lock, back row, and prop players were 7,760, 7,457, 7,301, 8,402, 8,500, 6,988, 5,481, 6,936, and 4,597 m, respectively. The average occurrence of high-intensity runs per match was 42, 35, 34, 86, 120, 74, 52, 26, and 18 for fullback, wing, center, five-eight, halfback, hooker, lock, back row, and prop players, respectively. The average distance traveled greater than 18 km·h-1 for fullback were 17 ± 2 m, wing 18 ± 2 m, center 18 ± 3 m, five-eight 16 ± 3 m, and halfback 17 ± 4 m. The average distance and range traveled greater than 18 km·h for hooker were 14 ± 3 m, lock 16 ± 2 m, back row 18 ± 3 m, and prop 16 ± 2 m. The use of global positioning systems has demonstrated plausibility to eliminate the use of grouping of positions in rugby league and for coaches to make specific training protocols for each position. Given the differences in movement demands of all 9 positions in rugby league, some positions would lack specificity to their positional requirements if using collective grouping for planning of training regimens.

Validity and interunit reliability of 10 Hz and 15 Hz GPS units for assessing athlete movement demands.

The purpose of this study was to assess the validity and interunit reliability of 10 Hz (Catapult) and 15 Hz (GPSports) Global Positioning System (GPS) units and investigate the differences between these units as measures of team sport athlete movement demands. A team sport simulation circuit was completed by 8 trained male participants. The movement demands examined included: total distance covered (TD), average peak speed, and the distance covered, time spent, and the number of efforts performed low-speed running (0.00-13.99 km · h(-1)), high-speed running (14.00-19.99 km · h(-1)), and very high-speed running (>20.00 km · h(-1)). The degree of difference between the 10 Hz and the 15 Hz GPS units and validity was assessed using a paired samples t-test. Pearson's correlations were also used for validity assessment. Interunit reliability was established using percentage typical error of measurement (%TEM) and intraclass correlations. The findings revealed that 10 Hz GPS units were a valid (p > 0.05) and reliable (%TEM = 1.3%) measure of TD. In contrast, the 15 Hz GPS units exhibited lower validity for TD and average peak speed. Further, as the speed of movement increased the level of error for the 10 Hz and 15 Hz GPS units increased (%TEM = 0.8-19.9). The findings from this study suggest that comparisons should not be undertaken between 10 Hz and 15 Hz GPS units. In general, the 10 Hz GPS units measured movement demands with greater validity and interunit reliability than the 15 Hz units, however, both 10 Hz and 15 Hz units provided the improved measures of movement demands in comparison to 1 Hz and 5 Hz GPS units.

Positional differences in professional rugby league match play through the use of global positioning systems.

The current use of tracking technology in the form of global positioning systems allows for a greater analysis of locomotor activities occurring in games and a larger volume of games when compared with time-motion analysis. Therefore, the aim of this study is to be the first to analyze the physiological demands of forwards and backs throughout the entirety of an Australian professional rugby league season. The movement patterns of 185 players from a professional rugby league club were recorded during 28 National Rugby League games played in Australia during the 2010 season. The players were clustered into 2 positional groups, backs and forwards. Maximum match-play time recorded was 99 minutes and 50 seconds in a semifinal game recorded for both a forward and back. The mean total distances covered in a game for forwards and backs were 5,964 ± 696 and 7,628 ± 744 m, respectively (p < 0.05). The maximum distance recorded by a forward was 10,511 and 10,359 m for a back. The average number of occurrences in high-intensity running (>18 km·h(-1)) was 23 ± 4 and for forwards and significantly higher backs with 35 ± 8 (p < 0.05). The maximum work rate in a 10-minute block of match play was 115 and 120 m·min(-1) of play for forwards and backs, respectively. Understanding the physiological demands of a sport is important for coaches to deliver athletes optimal training programs that elicit appropriate and specific physiological adaptation. The differences in locomotor activities, which occur between positions, need to be accounted for when developing training programs.

Pseudotumor cerebri associated with lithium use in an 11-year-old boy.

Pseudotumor cerebri, also termed idiopathic intracranial hypertension, is defined by increased intracranial pressure in the setting of normal brain imaging and cerebrospinal fluid analysis. It can often be associated with optic nerve head edema. Several medications have been associated with pseudotumor cerebri,(1) including the use of lithium carbonate in the adult population(3) as well as in adolescents.(4) Signs and symptoms of increased intracranial pressure typically resolve after cessation of lithium carbonate usage.(5) We report a case of the onset of pseudotumor cerebri associated with lithium treatment in a child who sustained long-term optic atrophy and vision loss and required acetazolamide treatment for approximately 1 year after cessation of lithium.

Use of a hydroxyapatite-coated stem in patients with Dorr Type C femoral bone.

Type C bone, as described by Dorr, exhibits both cellular and structural compromise, which presents a challenge for fixation of a total hip arthroplasty (THA). We evaluated the performance of the Omnifit HA stem, a hydroxyapatite-coated titanium alloy stem, by retrospectively reviewing the clinical and radiographic data of 15 patients with femoral Type C bone who received the stem during primary THA between 1991 and 1994. The patients were followed a minimum of 9 years (mean, 11.5 years; range, 9-14 years). The average age at surgery was 54 years and the average body mass index was 28. Eight of the patients were men. The median Harris hip score was 94.5 points. Radiographically, two independent reviewers identified all patients as Type C bone. The average canal to calcar isthmus ratio was 0.74 (range, 0.65-0.95). At most recent followup, four patients demonstrated proximal osteolysis. Using plain radiography we detected no patients with distal osteolysis or subsidence. At 9 to 14 years, the stem has performed well in a selected series of patients with poor bone quality and the outcomes compare favorably with previously reported findings using this design of stem in other bone types. These results support the decision to use a hydroxyapatite-coated stem in patients with Type C bone.

Structure, flexibility, and mechanism of the Bacillus stearothermophilus RecU Holliday junction resolvase.

Here we report a high resolution structure of RecU-Holliday junction resolvase from Bacillus stearothermophilus. The functional unit of RecU is a homodimer that contains a "mushroom" like structure with a rigid cap and two highly flexible loops extending outwards. These loops appear to be highly flexible/dynamic, and presumably are directly involved in DNA binding and holding it for catalysis. Structural modifications of both the protein and DNA upon their interaction are essential for catalysis. An Mg2+ ion is present in each of the two active sites in this homodimeric enzyme, and two water molecules are coordinated with each Mg2+ ion. Our data are consistent with one of these water molecules acting as a nucleophile and the other as a general acid. The identities of the general base and general acid involved in catalysis and the Lewis acid that stabilizes the pentacovalent transition state phosphate ion are proposed. A model for the RecU-Holliday junction DNA complex is also proposed and discussed in the context of DNA binding and cleavage.

The use of a hydroxyapatite-coated primary stem in revision total hip arthroplasty.

Proximal ingrowth of femoral components in total hip arthroplasty (THA) is desirable because it minimizes proximal stress shielding associated with distal ingrowth stems and maximizes bone stock. This is a retrospective evaluation of initial results of revision THA using a proximally hydroxyapatite-coated femoral stem nominally designed for primary use. Patients requiring femoral stem revision were included if they had sufficient femoral bone stock to support a proximally fixed prosthesis (n = 33). This represents 53% of the femoral revisions performed during the period of the study. The average follow-up was 5 years (range 48-88 months). The mean Harris hip and Oxford hip scores were 86.5 and 25.2, respectively. Radiographically, 100% of the stems demonstrated bone ingrowth fixation. These results are superior to previous reports of primary cementless stems for revision THA. The use of a cementless nonmodular implant provides a viable option in some patients undergoing revision THA.

Case report: a modified constraint-induced therapy (mCIT) program for the upper extremity of a person with chronic stroke.

The purpose of this case report was to assess the effect of a reduced intensity protocol for daily modified constraint-induced therapy (mCIT) without use of a restraint on the function of the upper extremity (UE) in an individual with a chronic stroke. A 57 year-old patient one year following a stroke participated in a two-hour mCITprogram for ten weekdays over a period of two weeks. During this period, voluntary use of the involved extremity was encouraged for 90% of waking hours at home without use of a restraint. Examination was conducted before and after intervention, and at a one month follow-up visit. Outcome measures included: the Wolf Motor Function Test (WMFT), the Motor Activity Log (MAL), and motion analysis of a reach and grasp task using Charnwood's CODA mpx 30. The patient improved or remained the same in functional upper extremity tasks on both the WMFT and MAL. The data from the motion analysis showed that grasp time and maximum pinch angle improved for bilateral UEs. Reaching profile graphed over time had fewer changes in velocity and fewer periods of acceleration and deceleration post-intervention. This reduced intensity program shows promise as an effective, feasible, and patient-preferred application of mCIT in a clinical setting.