Search

Hamstring injuries have not been under research in physical education teacher education (PETE) students so far. Within the frame of the development of an injury prevention program, for this study we conducted an analysis of modifiable risk factors for hamstring injuries in PETE students. Hamstring injuries of 102 freshmen bachelor PETE students were registered prospectively during one academic year. Eighty-one students completed maximum muscle strength tests of hip extensors, hamstrings, quadriceps (isometric) and hamstrings (eccentric) at the start of the academic year. Sixty-nine of the latter completed a single leg hop for distance (SLHD). Risk factors for hamstring injuries were statistically detected using logistic regression. Sixteen hamstring injuries (0.16 injuries/student/academic year; 0.46 injuries/1000 h) occurred to 10 participants. Eight cases were included in the risk factor analysis. Lower eccentric hamstring strength (odds ratio (ODD) = 0.977; p = 0.043), higher isometric/eccentric hamstring strength ratio (ODD = 970.500; p = 0.019) and lower score on the SLHD (ODD = 0.884; p = 0.005) were significant risk factors for hamstring injury. A combination of eccentric hamstring strength test and SLHD could give a good risk analysis of hamstring injuries in PETE students. This might offer great perspectives for easily applicable screening in a clinical setting. [ABSTRACT FROM AUTHOR]

Reasons for performing the study Atrial fibrillation ( AF) is the most important dysrhythmia affecting performance in horses and has been associated with incoordination, collapse and sudden death. Limited information is available on ventricular response during exercise in horses with lone AF. Objectives To investigate ventricular response in horses with lone AF during a standardised lungeing exercise test. Methods A modified base-apex electrocardiogram was recorded at rest and during a standardised lungeing exercise test from 43 horses diagnosed with lone AF. During the test horses walked for 7 min, trotted for 10 min, cantered for 4 min, galloped for 1 min and recovered for 7 min. Results Individual average heart rate during walk ranged from 42 to 175 beats/min, during trot from 89 to 207 beats/min, during canter from 141 to 269 beats/min, and during gallop from 191 to 311 beats/min. Individual beat-to-beat maximal heart rate ranged from 248 to 492 beats/min. Ventricular premature depolarisations were present in 81% of the horses: at rest (16%), during exercise (69%), and during recovery (2%). In 33% of the horses, broad QRS complexes with R-on- T morphology were found. Conclusions Exercising horses with lone AF frequently develop disproportionate tachycardia. In addition, QRS broadening and even R-on- T morphology is frequently found. QRS broadening may originate from ventricular ectopic foci or from aberrant intraventricular conduction, for example due to bundle branch block. This might explain the high number of complexes currently classified as ventricular premature depolarisations. Potential relevance Prevalence of QRS broadening and especially R-on-T was very high in horses with AF and was found at low levels of exercise. These dysrhythmias are considered risk factors for the development of ventricular tachycardia and fibrillation and they might explain signs of weakness, collapse or sudden death that have been reported in horses with AF. [ABSTRACT FROM AUTHOR]

Reasons for performing study: The use of two-dimensional speckle tracking (2DST) for quantification of left ventricular (LV) function has recently been described in horses using long-axis images and short-axis images at chordal but not at papillary muscle level. Objectives: To compare the feasibility and reliability of 2DST for quantification of circumferential and radial LV function in short-axis images at papillary muscle and chordal level. Methods: Repeated echocardiographic examinations were performed on 10 healthy trotter horses by 2 observers from a right parasternal short-axis view at papillary muscle and chordal level. Segmental and averaged peak values and timing of circumferential and radial strain and strain rate, radial displacement and rotation were measured in 6 LV wall segments in each imaging plane. Global peak values were calculated for circumferential strain and strain rate. The inter- and intraobserver within- and between-day variability was assessed by calculating coefficients of variation for repeated measurements. Results: 2DST analysis was feasible in each cardiac cycle, although tracking was often inadequate during early diastole. Measurements of averaged systolic circumferential and radial strain and strain rate and radial displacement as well as global circumferential strain and strain rate could be determined with low variability. Early and late diastolic strain rate and systolic rotation showed a moderate variability. Radial segmental measurements were more reliable than circumferential measurements. The interventricular septum showed a higher circumferential and lower radial strain compared with the LV free wall. Peak timing was earlier at papillary muscle compared with chordal level. Conclusions: 2DST measurements of global and regional circumferential and radial LV wall motion are feasible both at papillary muscle and chordal level. Potential relevance: Several measurements had good reliability and should be used for evaluation of the technique in a clinical setting. [ABSTRACT FROM AUTHOR]

Reasons for performing study: In human medicine, oesophageal electrocardiography (ECG) is a well-established technique that magnifies P waves with respect to the QRS complex. Objectives: To investigate the feasibility of oesophageal ECG recording in horses and its ability to produce larger P waves compared with base-apex and unipolar recordings. Methods: Bipolar and unipolar ECG were performed using oesophageal and surface electrodes. Oesophageal ECG was obtained from 6 different recording configurations at different oesophageal depths. Amplitudes of P, Q, R, S and T waves were measured from 3 different cardiac cycles for each recording configuration and depth. Results: Oesophageal ECG was feasible in all horses. For all oesophageal recording configurations, significantly larger P waves were recorded from a depth that equalled 'height of the withers + 10 cm' (HW+10) than from any other depth. P/QRSmagn, the ratio between the P wave and QRS complex magnitudes, was largest for intraoesophageal recordings with an interelectrode distance of 10 cm, at HW+10, where it was significantly larger than base-apex and unipolar recordings. Base-apex recording resulted in significantly smaller P waves than all other recording configurations and significantly smaller P/QRSmagn ratios than all other recording configurations except one combined oesophageal-surface recording (E/Slow). Conclusions: Oesophageal ECG recording is feasible in horses and effective in magnifying P wave amplitude. Potential relevance: The procedure is promising for diagnosis of supraventricular tachydysrhythmias and might be used in electrophysiological studies and for cardiac pacing. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the long-term effectiveness of a spine care education programme conducted in 9- to 11-year-old schoolchildren. The study sample included 96 intervention subjects and 98 controls (9- to 11-year-olds at baseline). Intervention consisted of a 6-week school-based back education programme (predominantly biomechanically oriented) and was implemented by a physical therapist. Self-reported outcomes on back care knowledge, spinal care behaviour, self-efficacy towards favourable back care behaviour, prevalence of back and neck pain during the week and fear-avoidance beliefs were evaluated by the use of questionnaires. Post-tests were performed within 1 week after programme completion, after 1 year and after 8 years. Whereas the educational back care programme resulted in increased back care knowledge up to adulthood (P < 0.001), intervention did not change spinal care behaviour or self-efficacy. Pain prevalence figures increased less in the experimental group compared to the controls over the 8-year time span, yet statistical significance was not reached. Dropout analysis revealed spinal pain prevalence rates to be different in both groups throughout the study, including at baseline. Back education at young age did not reinforce fear-avoidance beliefs up to adulthood. Predominantly biomechanical oriented back education in elementary schoolchildren is effective in improving the cognitive aspect of back care up to adulthood, yet not in changing actual behaviour or self-efficacy. The current study does not provide evidence that educational back care programmes have any impact on spinal pain in adulthood. The true long-term impact of school-based spinal health interventions on clinically relevant outcome measures merits further attention. [ABSTRACT FROM AUTHOR]

The human foot was anatomically modern long before footwear was invented, and is adapted to barefoot walking on natural substrates. Understanding the biomechanics of habitually barefoot walkers can provide novel insights both for anthropologist and for applied scientists, yet the necessary data is virtually non-existent. To start assessing morphological and functional effects of the habitual use of footwear, we have studied a population of habitually barefoot walkers from India (n = 70), and compared them with a habitually shod Indian control group (n = 137) and a Western population (n = 48). We focused on foot metrics and on the analysis of plantar pressure data, which was performed using a novel, pixel based method (Pataky and Goulermas 2008, Journal of Biomechanics, 41, 2136). Habitually shod Indians wore less often, and less constricting shoes than Western people. Yet, we found significant differences with their habitually barefoot peers, both in foot shape and in pressure distribution. Barefoot walkers had wider feet and more equally distributed peak pressures, i.e. the entire load carrying surface was contributing more uniformly than in habitually shod subjects, where regions of very high or very low peak pressures were more apparent. Western subjects differed strongly from both Indian populations (and most from barefoot Indians), by having relatively short and, especially, slender feet, with more focal and higher peak pressures at the heel, metatarsals and hallux. The evolutionary history of humans shows that barefoot walking is the biologically natural situation. The use of footwear remains necessary, especially on unnatural substrates, in athletics, and in some pathologies, but current data suggests that footwear that fails to respect natural foot shape and function will ultimately alter the morphology and the biomechanical behaviour of the foot. [ABSTRACT FROM AUTHOR]

It is commonly accepted that vertical jump performance is a good indicator of maximal joint power. Some studies, however, have indicated that knee joint power output in the vertical jump is limited due to forward trunk inclination early in the push-off. The aim of this experimental study was to investigate the effect of forward trunk inclination on joint power output in vertical jumping. A group of 20 male subjects performed maximal vertical countermovement jumps from stance while minimizing the contribution of arm swing by holding their hands on their hips (arms akimbo). They also performed maximal jumps while holding the trunk as upright as possible throughout the jump, still holding the arms akimbo. Jump height, joint kinematics (angles), and joint kinetics (torque, power) were calculated. Jump height of vertical jumps while holding the trunk upright was 10% less than in normal jumps. Hip joint power was decreased by 37% while knee joint power was increased by 13%. Ankle joint power did not change. These results demonstrated that maximal jump performance does not necessarily represent maximal power of each individual joint. The implication is that jump performance may well be a good representation of overall joint power; it is, however, not an accurate measure to evaluate maximal individual joint power as part of contemporary training and rehabilitation methods. [ABSTRACT FROM AUTHOR]

Aims: The composting process needs to be validated for its hygienic status in order to ensure that it is free of pathogens. Generally, this is evaluated through temperature monitoring, or additionally through active inoculation and monitoring of indicator organisms. We aimed to develop a monitoring method for the heat-resistant indicator organism Salmonella enterica ssp. enterica serovar Senftenberg strain W775 for detection in composting biowastes. Methods and Results: The method development is comprised of: (i) optimization of molecular detection of bacteria belonging to the genus Salmonella; (ii) identification of a DNA marker for Salmonella strain W775; and (iii) development of a multiplex polymerase chain reaction (PCR)-based on both DNA markers. Subsequently, Salmonella strain W775 was inoculated and monitored during composting of biowastes in an industrial composting facility. Conclusions: A highly sensitive and specific detection of viable cells was obtained by enriching the compost sample prior to multiplex PCR analysis. Complete inactivation of Salmonella strain W775 was obtained within 4 days in an industrial composting facility at temperatures ranging between 41 and 57°C. Significance and Impact of the Study: We describe a monitoring method for the simultaneous detection of naturally occurring Salmonella strains and artificially introduced Salmonella strain W775 in composting biowastes that can be applied in routine analysis. [ABSTRACT FROM AUTHOR]

Determination of the minimum requirements (time–temperature relationship and moisture content) that are needed for a sufficient eradication of an indicator organism. Methods and Results: To determine the hygienic safety of composting processes, the indicator organism Salmonella enterica ssp. enterica serotype Senftenberg strain W 775 (further abbreviated as W 775) was artificially inoculated on a meat carrier and monitored subsequently. Different types of composting processes, e.g. composting in enclosed facilities, in open-air and in-vessel composting, were investigated. The waste feedstocks used in this work were either biowastes (i.e. vegetable, fruit and garden wastes; also called source-separated household wastes) or pure garden wastes. Beside these large-scale trials, we also conducted some lab experiments in order to determine the impact of temperature, moisture content and the presence of an indigenous microflora on the eradication of W 775. We found the temperature to be the most important parameter to eradicate W 775 from compost. When the temperature of the compost heap is 60°C and the moisture content varies between 60–65%, W 775 (108 CFU g−1) will be inactivated within 10 h of composting. The moisture content is, beside temperature, a second parameter that influences the survival of W 775. When the water content of the composting materials or meat carriers is reduced, a higher survival rate of W 775 was observed (survival rate increases 0·5 log10 unit when there is a reduction of 5% in moisture content). In addition, other parameters (such as microbial antagonism, toxic compounds, etc.) have an influence on the survival of W 775 as well. Conclusions: Our study demonstrates that all types of composting processes tested in this work were sufficient to eradicate W 775 providing that they are well managed in terms of temperature and moisture content. Significance and Impact of the Study: To give a better view on the parameters of importance for the eradication of W 775 during composting. [ABSTRACT FROM AUTHOR]

Background The motor co-ordination problems of children with Developmental Coordination Disorder (DCD) have been frequently associated with poor visuospatial processing. In order to extend these findings mainly based on fine motor experiments, the present study investigates the contribution of vision to the control of walking in children with DCD. Methods Children with DCD ( n = 12) walked at their preferred speed on a straight, firm and uncluttered walkway in a condition with normal lighting and in a dark condition. Spatiotemporal gait variables were assessed by means of a three-dimensional ProReflex camera system and compared with the gait pattern of matched, typically developing (TD) children ( n = 12). Results In normal lighting, the gait pattern of both groups was similar, with the exception of subtle differences in the temporal phasing, showing a slightly longer support phase in the children with DCD. In the dark, step frequency and step length were decreased in the children with DCD, resulting in a significantly slower walking velocity. In addition, the medio-lateral excursion of the centre of mass tended to increase in this group. In the TD children, adaptations to the spatiotemporal pattern remained absent. Conclusions These results suggest that children with DCD are more dependent on global visual flow information than TD children for the maintenance of balance and the control of velocity during walking. This increased dependency on visual control might be associated with a poorly developed internal sensorimotor model. [ABSTRACT FROM AUTHOR]

Six horses without underlying cardiac disease were presented because of atrial fibrillation of between 5 and 12 months duration. These horses received an intravenous amiodarone treatment of 5 mg/kg/h for 1 h followed by 0.83 mg/kg/h for 23 h and subsequently 1.9 mg/kg/h for 30 h. During treatment, clinical signs were monitored and a surface ECG and an intra-atrial electrogram were recorded. Infusion was discontinued when sinus rhythm or side effects occurred. Four horses successfully cardioverted, of which one showed symptoms of hind limb weakness and weight shifting. Two horses did not cardiovert and showed similar side effects. In all horses, side effects disappeared within 6 h after termination of treatment. Cardiac side effects, such as pro-arrhythmia, were not seen in any of the horses. Total bilirubin slightly increased in three horses and normalised within four days. It was concluded that amiodarone has the potential to treat naturally occurring chronic atrial fibrillation in horses, although further research is needed to refine the infusion protocol. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to determine prospectively gait related risk factors for exercise-related lower leg pain (ERLLP) in 400 physical education students. Static lower leg alignment was determined, and 3D gait kinematics combined with plantar pressure profiles were collected. After this evaluation, all sports injuries were registered by the same sports physician during the duration of the study. Forty six subjects developed ERLLP and 29 of them developed bilateral symptoms thus giving 75 symptomatic lower legs. Bilateral lower legs of 167 subjects who developed no injuries in the lower extremities served as controls. Cox regression analysis revealed that subjects who developed ERLLP had an altered running pattern before the injury compared to the controls and included (1) a significantly more central heel-strike, (2) a significantly increased pronation, accompanied with more pressure underneath the medial side of the foot, and (3) a significantly more lateral roll-off. These findings suggest that altered biomechanics play a role in the genesis of ERLLP and thus should be considered in prevention and rehabilitation. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to establish a representative reference dataset for temporal characteristics of foot roll-over during barefoot jogging, based on plantar pressure data collected from 220 healthy young adults. The subjects ran at 3.3ms-1 over a 16.5m long running track, having a built-in pressure platform mounted on a force platform. The initial contact, final contact, time to peak pressure and the duration of contact at the lateral and medial heel, metatarsal heads I to V and the hallux were measured. Temporal plantar pressure variables were found to be reliable (93% of ICC coefficients above 0.75) and both gender and asymmetry influences could be neglected. Foot roll-over during jogging started with heel contact followed by a latero-medial contact of the metatarsals and finally the hallux. After heel off, the forefoot started to push off at the lateral metatarsals, followed by a more central push off over the second metatarsal and finally over the hallux. Based on the plantar pressure data, the stance phase during running was divided into four distinct phases: initial contact (8.2%), forefoot contact (11.3%), foot flat (25.3%) and forefoot push off (55.1%). These findings provide a reliable and representative reference dataset for temporal characteristics of foot roll-over during jogging of young adults that may also be relevant in the evaluation of running patterns. [Copyright &y& Elsevier]

BACKGROUND: Many variables have been retrospectively associated with ankle sprains. However, very little is known about factors predisposing people to these injuries. HYPOTHESIS: Measurable intrinsic factors might predispose male athletes to ankle sprains. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: A total of 241 male physical education students were evaluated for possible intrinsic risk factors for inversion sprains at the beginning of their academic study. The evaluated intrinsic risk factors included anthropometrical characteristics, functional motor performances, ankle joint position sense, isokinetic ankle muscle strength, lower leg alignment characteristics, postural control, and muscle reaction time during a sudden inversion perturbation. Subjects were followed prospectively for 1 to 3 years. RESULTS: A total of 44 (18%) of the 241 male subjects sustained an inversion sprain; 4 sprained both ankles. Cox regression analysis revealed that male subjects with slower running speed, less cardiorespiratory endurance, less balance, decreased dorsiflexion muscle strength, decreased dorsiflexion range of motion, less coordination, and faster reaction of the tibialis anterior and gastrocnemius muscles are at greater risk of ankle sprains. CONCLUSION: Based on our findings, it is suggested that running speed, cardiorespiratory endurance, balance, dorsiflexion strength, coordination, muscle reaction, and dorsiflexion range of motion at the ankle are associated with the risk of ankle inversion sprains in male subjects. [ABSTRACT FROM AUTHOR]