305 research outputs found
THE INFLUENCE OF SIDE DOMINANCE ON UPPER BODY KINEMATICS DURING RUGBY PASSES FROM THE GROUND
This study described rugby passing technique in a group of 13 highly proficient players. Upper body kinematics (500 Hz) were assessed during six passes at a target positioned 8 m away from both dominant and non-dominant sides, with pass accuracy recorded subjectively using a 5-point scale. Passes to the preferred side were faster (P=0.02) and more accurate (P=0.001) than those to the non-preferred side. Variability analysis (NoRMS) showed greater shoulder and elbow movement variability, with greater standard deviation values at ball release for passes to the non-dominant side. Maximum shoulder flexion (lead) and adduction (trailing) velocities were moderately correlated with pass velocity (r=0.41 to r=0.48). Results suggest that despite displaying a high level of passing proficiency, participants presented with a bias when passing towards their dominant side
LOWER LIMB MOVEMENT VARIABILITY DURING RUGBY UNION PLACE KICKING
Place kicking accuracy has a significant impact rugby match outcomes. This project investigated the variability of the kicking leg kinematics and the consistency on the stance and kicking foot positions at ball contact in a group of seven highly proficiency kickers. Kinematic data were collected using a high speed motion capture system (500 Hz) during six simulated attempts on goal. Movement variability was assessed using Normalised Root Mean Square of the swing leg pelvis, hip and knee kinematics, and the standard deviation of the stance foot at opposite plant and kicking foot at ball contact (BC). Results suggest a strong relationship between stance foot placement, swing leg movement variability and the orientation of the kicking foot at BC. This pilot study highlighted the importance of movement variability in determining consistent foot placement at BC in place kicking
THREE DIMENSIONAL PELVIS AND HIP INTERACTION DURING PUNT KICKING: SKILLED VERSUS NOVICE PLAYERS
The purpose of this study was to examine the interrelationships between pelvis and hip kinematics and punt kicking proficiency during a series of kicks for maximum distance/velocity. Three dimensional data (500 Hz) were collected during punt kicks for maximum velocity performed by 15 semi professional (S-Pro) Rugby Union players and 15 male recreational (Rec) kicking sport athletes. Results showed that the punt kicking technique of the S-Pro group involved complex multiplanar pelvis movements, with greater emphasis on axial pelvis rotation than the Rec group. These movement patterns have the potential to increase the stretch-shorten cycle in the kicking leg. Conversely, the punt kicking technique of the Rec group involved simple flexion-extension pelvis and hip movement patterns, a strategy that appears to limit punt kicking ball velocity
THE EFFECT OF PRIOR CYCLING ON LEG STIFFNESS DURING RUNNING IN HIGH PERFORMANCE TRIATHLETES
The purpose of this study was to investigate the influence cycling has on lower limb stiffness during the run leg in triathletes. Seven well trained triathletes completed a triathlon-run (TR; run preceded by a 40 km cycle) and a control-run (CR; run at the same pace as TR, but without a prior cycle). Vertical, hip, knee and ankle stiffness measured during double leg jumping (2.2 Hz) were compared both before and after the cycle leg and between TR and CR conditions. Maximum hip and knee moments and knee joint stiffness were significantly greater immediately following cycling. However, maximum hip moments and hip joint stiffness were lower in CR than TR. This study provided an insight into how joint stiffness is altered following cycling and may help explain the perceived loss of coordination reported frequently by triathletes at the start of the run leg
IDENTIFICATION OF THE POP-UP ACCELERATION WAVEFORM SIGNAL: A CASE STUDY
The purpose of this case study was to assess the feasibility of using accelerometers to identify and analyse the acceleration waveform signals of the pop-up movement. An experienced male recreational surfer performed 10 dry-land pop-ups with accelerometers (1000 Hz) attached to the sacrum and lateral aspect of each shank. The waveform signals of the pop-up were successfully identified at each instrumentation site using a combination of acceleration and video data. Several movement events that occurred during the pop-up were also able to be detected within each of the mean resultant acceleration signals. These findings suggest that accelerometers can viably be used to detect and analyse the waveform signals of the pop-up. This provides initial evidence that accelerometers are a suitable tool for collecting kinematic data of surfing performances
JOINT MOMENTS DURING INSTEP KICKS IN FOOTBALL PLAYERS WITH AND WITHOUT PREVIOUS GROIN PAIN
This study examined how previous groin pain and approach angle affects stance leg and lumbar moments during instep kicks. Male football players with and without previous groin pain (n=11, and n=10) performed instep kicks from 45° and 60° angles while kinetic and kinematic data were recorded (1000Hz and 500Hz respectively). 3D stance leg net joint moments of the hip, knee, and ankle were calculated at peak swing knee flexion and ball contact and the sagittal L5/S1 joint moment was examined throughout the kick. Foot speed at ball contact indicated performance. Players with previous groin pain had lower moments during the kick compared to uninjured controls, but there was no difference in performance. This suggests that the players with previous groin pain utilized an aberrant kicking pattern that offloads certain joints but may cause compensations elsewhere in the kinetic chain
Transparency and financial reporting in mid-twentieth century British banking
Post-print draft dated 30 November 2007. Final version published by Elsevier; available online at http://www.journals.elsevier.com/Until 1970, British banks were firm believers in the merits of ‘non-disclosure’, which obscured their ‘true’ profits and capital through profits smoothing and the use of hidden reserves. Many other companies adopted the same view for as long as legislation permitted, but there were special reasons why non-disclosure endured for longer in banking. This paper examines the persistence and demise of non-disclosure in banking, placing it in the context of the wider development of financial reporting in Britain, and highlights similarities and differences in financial reporting between banks and other types of company
The effect of increasing heel height on lower limb symmetry during the back squat in trained and novice lifters
Background: Symmetry during lifting is considered critical for allowing balanced power production and avoidance of injury. This investigation assessed the influence of elevating the heels on bilateral lower limb symmetry during loaded (50% of body weight) high-bar back squats.
Methods: Ten novice (mass 67.6 ± 12.4 kg, height 1.73 ± 0.10 m) and ten regular weight trainers (mass 66.0 ± 10.7 kg, height 1.71 ± 0.09 m) were assessed while standing on both the flat level floor and on an inclined board. Data collection used infra-red motion capture procedures and two force platforms to record bilateral vertical ground reaction force (GRFvert) and ankle, knee and hip joint kinematic and kinetic data. Paired t-tests and statistical parametric mapping (SPM1D) procedures were used to assess differences in discrete and continuous bilateral symmetry data across conditions.
Results: Although discrete joint kinematic and joint moment symmetry data were largely unaffected by raising the heels, the regular weight trainers presented greater bilateral asymmetry in these data than the novices. The one significant finding in these discrete data showed that raising the heels significantly reduced maximum knee extension moment asymmetry (P = 0.02), but in the novice group only. Time-series analyses indicated significant bilateral asymmetries in both GRFvert and knee extension moments mid-way though the eccentric phase for the novice group, with the latter unaffected by heel lift condition. There were no significant bilateral asymmetries in time series data within the regular weight training group.
Conclusions: This investigation highlights that although a degree of bilateral lower limb asymmetry is common in individuals performing back squats, the degree of this symmetry is largely unaffected by raising the heels. Differences in results for discrete and time-series symmetry analyses also highlight a key issue associated with relying solely on discrete data techniques to assess bilateral symmetry during tasks such as the back squat
Be prepared – exploring future climate-related risk for residential and commercial real-estate portfolios
This article explores how real estate investors and lenders can assess and manage the physical risks of climate change through wellestablished risk models and climate scenarios. The authors propose a methodology that real estate investors and lenders can use to improve their understanding and management of these risks. The methodology is applied to a sample of 12 real estate portfolios with a total market value in excess of £2 trillion, spread across Europe, North and South America, and Asia, investigating the impacts of climate change on losses from floods and winter storms (UK) as well as tropical cyclones (North America and the Pacific Rim). The estimated changes in risk, especially in the climate scenario most aligned with the current warming trajectory, raises important questions for investors, lenders, insurers, and policymakers as to how these new levels of risk can be managed in the most cost-effective manner
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